JP2001108642A - Thermal analyzer for electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the precisely corrected flow rate of a fluid around a cooling fan toy taking into consideration the characteristic of the cooling fan on the basis of the operating flow rate of the fan calculated on the basis of characteristic data on the cooling fan used to dissipate the heat of an electronic apparatus in the thermal analysis at the designing stage of the electronic apparatus. SOLUTION: In a fan-characteristic calculating and processing part 63 in a computing and processing part 6A, the pressure of a node is corrected the correction processing operation of a flow rate around a fan is executed, and the judgment processing operation of a residual error at a later stage is executed. In the correction processing operation of the flow rate around the fan network data 43 is first read out, the element of the fan is extracted from it, and pressure data on nodes constituting both ends of the element of the fan is read out. As a result, when fan characteristic data 72 in a library data storage part 7A is used, the operating flow rate of the fan is obtained. By using the obtained operating flow rate of the fan, the flow rate of a fluid around the fan is found. By executing the above processing operations, the thermal analysis of an electronic can be performed by taking into consideration the characteristic of the fan.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal analysis apparatus for electronic equipment, and more particularly, to a thermal analysis apparatus for electronic equipment which performs a heat / fluid analysis simulation by a computer for supporting thermal design of electronic equipment.

[0002]

2. Description of the Related Art In recent years, design verification and analysis calculation using a computer, so-called CAE (COMPUTER AIDE)
D ENGINEERING) has been used in various fields. In particular, progress has been remarkable in the analysis of structural strength, and it has already been widely spread. On the other hand, with the development of the integration technology of semiconductor elements, the density of electronic device internal circuits is rapidly increasing. MPU (MICRO PROCESSING) which is the core of the information processing function
(UNIT), its operating frequency is increasing at an accelerating rate, and the power consumption per chip is also rapidly increasing from several watts to several tens of watts. In addition, electronic devices themselves have been downsized, and power consumption per unit volume has been steadily increasing.

[0003] Against this background, thermal design of electronic equipment has become increasingly important, and analysis and simulation using a computer have also become widespread in thermal design of electronic equipment. Most cooling methods for electronic devices are air-cooled. For this reason, fluid analysis (simulating air flow) is indispensable for performing thermal analysis. Generally, a method is used in which “Navier-Stokes equation (fluid equation of motion)” is combined with an energy equation using a method such as a difference method, a finite element method, and a finite volume method. However, these methods are difficult to find a solution quickly and stably, and difficult to handle except for engineers with special expertise. A thermal analysis CAE system using a node method that can solve a heat / fluid problem at high speed and does not require specialized knowledge has been proposed (JP-A-4-30270, JP-A-4-7675). etc).

FIG. 2 shows a configuration of a thermal analysis CAE system using a nodal method as a conventional thermal analysis apparatus. This thermal analysis CAE system includes a display device 1, an input device 2, an input processing unit 3, a data storage unit 4, a network data generation processing unit 5, an arithmetic processing unit 6, and a library data storage unit 7.

The input device 2 is connected to an input / output processing unit 3,
Used for inputting data and processing commands. The input / output processing unit 3 includes a three-dimensional shape data processing unit 31 and a result display processing unit 32. The display device 1 is for displaying the status of the device and the processing result, and is connected to the input / output processing unit 3.

[0006] The input / output processing unit 3, the network data generation processing unit 5 and the arithmetic processing unit 6 are connected via a data storage unit 4. The data storage unit 4 stores the shape data 4
1, node coordinate data 42, network data 43,
A storage area for storing the pressure air volume data 44 and the temperature data 45 is included. These data can be used in the input / output processing unit 3, the network data generation processing unit 5, and the arithmetic processing unit 6, and various types of data stored in the data storage unit 4 can be exchanged.

The three-dimensional shape data processing section 31 of the input / output processing section 3 stores the processing result in the shape data 41 in the data storage section 4.
Connected to be stored as The data storage unit 4 is connected so that the stored shape data 41 is input to the result display processing unit 32 of the input / output processing unit 3.
Similarly, the data storage unit 4 is connected so that various data such as node coordinate data 42, network data 43, pressure air volume data 44, and temperature data 45 are input to the result display processing unit 32 of the input / output processing unit 3. I have.

The data storage unit 4 is connected to the area division processing unit 51 so that the shape data 41 is transmitted to the area division processing unit 51 of the network data generation processing unit 5. The area division processing unit 51 is connected to the data storage unit 4 so that the processing result is stored as the node coordinate data 42. Further, the data storage unit 4 stores the node coordinate data 42 in the ventilation circuit generation unit 52 and the heat circuit generation unit 53 so that the node coordinate data 42 is transmitted to the ventilation circuit generation unit 52 and the heat circuit generation unit 53 of the network data generation processing unit 5. It is connected. The ventilation circuit generator 52 and the thermal circuit generator 53 are connected to the data storage unit 4 so that the processing results are stored as network data 43. Further, the data storage unit 4 stores the network data 43 so that the stored network data 43 is transmitted to the arithmetic processing unit 6.
It is connected to the. The arithmetic processing unit 6 is connected to the data storage unit 4 so that the processing result is stored as the pressure air volume data 44 and the temperature data 45.

The network data generation processing section 5 includes an area division processing section 51, a ventilation circuit generation section 52, and a thermal circuit generation section 53.
The ventilation circuit generator 52 and the heat circuit generator 53 are connected in order. The thermal circuit generator 53 of the network data generator 5 is connected to the processor 6 so that the processing result is input to the processor 6. The arithmetic processing unit 6 includes a ventilation circuit arithmetic processing unit 61 and a heat circuit arithmetic processing unit 62.
1. The thermal circuit operation processing unit 62 is connected in order.

The library data storage unit 7 includes a storage area for storing pressure loss coefficient data 71, fan characteristic data 72, temperature material property data 73, and heat transfer coefficient data 74. This library data storage unit 7
The pressure loss coefficient data 71, the fan characteristic data 72, and the temperature material property data 73 are stored in the network data generation processing unit 5.
Is connected to the ventilation circuit generator 52 so as to be transmitted to the ventilation circuit generator 52. The library data storage unit 7 is also connected to the thermal circuit generation unit 53 so that the temperature and material property data 73 is transmitted to the thermal circuit generation unit 53 of the network data generation processing unit 5. 74 is connected to the arithmetic processing unit 6 so as to be transmitted to the arithmetic processing unit 6.

Next, the operation of the conventional thermal analysis CAE system will be described.

First, when desired data and processing commands are input by the input device 2, the three-dimensional shape data processing unit 31 of the input / output processing unit 3 converts the shape of the electronic device to be analyzed into a straight line, a circle, or an arc. Etc. are taken in as figure shape data. Further, the data is stored as shape data 41 in the data storage unit 4.

While the shape data 41 is transmitted to the result display processing unit 32 of the input / output processing unit 3, it is transmitted to the area division processing unit 51 of the network data generation processing unit 5. In the area division processing unit 51, the whole electronic device to be analyzed is divided into small areas, and the coordinates of the center of gravity of the small area are calculated to generate nodes. Further, the generated node coordinates are stored in the data storage unit 4 as node coordinate data 42. Next, in the ventilation circuit generation unit 52, the fluid resistance of each part of the fluid part is calculated based on the node coordinate data 42, the pressure loss coefficient data 71, the fan characteristic data 72, and the temperature material property data 73. A ventilation circuit connected by resistors is generated. Similarly, the thermal circuit generation unit 53 calculates the heat conduction resistance of each part of the solid portion and the heat transfer resistance between the solid and the fluid from the node coordinate data 42 and the temperature material property data 73, and assigns each small area to these. A thermal circuit is created that is coupled by heat conduction and heat transfer resistance. Here, the generated ventilation circuit and heat circuit are stored in the data storage unit 4 as network data 43.

Next, the operation of the arithmetic processing unit 6 will be described with reference to FIG. FIG. 6 shows a processing routine of the arithmetic processing unit 6.

The processing of the arithmetic processing section 6 is such that the processing of the ventilation circuit arithmetic processing section 61 and the processing of the thermal circuit arithmetic processing section 62 are executed in chronological order. In the process of 61, the processes of steps 202 to 212 are executed. Next, in the processing of the thermal circuit arithmetic processing unit 62, the processing of steps 214 to 224 is executed.

First, the ventilation circuit arithmetic processing unit 61 assumes a node pressure (step 202), obtains a flow rate using a predetermined pressure loss equation (step 204), reads a predetermined pressure correction equation, and reads the pressure correction equation. A correction pressure is obtained using the correction formula (step 206), and then the pressure of the node is corrected (step 208). Then, until the residual error becomes smaller than the allowable value (step 212), the processing from step 204 onward is repeated. At this time, if the residual error is equal to or larger than the allowable value, the pressure update pressure loss coefficient is corrected (step 210).

Next, the thermal circuit arithmetic processing unit 62 calculates the thermal conductivity and advection term in accordance with the flow rate between the fluid nodes (step 214), and obtains the temperature of the node using a predetermined thermal conduction equation (step 214). Step 216). Then, until the residual error becomes less than the allowable value (step 218), the above step 2 is performed.
The processing after 16 is repeated. Further, when the residual error is equal to or larger than the allowable value (step 220), when the buoyancy is considered (step 222), the buoyancy is calculated (step 22).
4), Step 2 in the processing of the ventilation circuit arithmetic processing unit 61
The process after 04 is repeated. If the buoyancy is not taken into account (step 222), the processing routine ends.

As a result, the ventilation circuit arithmetic processing unit 61 calculates the fluid node pressure and the air volume between the fluid nodes,
Further, the thermal circuit operation processing unit 62 calculates the temperatures of all the nodes. The calculated fluid node pressure and the air volume between the fluid nodes are pressure air volume data 44, and the temperatures of all the nodes are temperature data 45 as data storage unit 4.
Is stored.

The various data stored in the data storage unit 4 obtained by the above processing are processed into a temperature distribution, an air volume distribution, and the like by the result display processing unit 32 of the input / output processing unit 3, and are processed by the display device 1. Visually displayed.

On the other hand, due to the rapid increase in heat generation density in recent electronic devices as described above, a forced air cooling system using a cooling fan for cooling devices has recently become the mainstream. By using a fan, the heat radiation capability of the device can be easily increased up to several times. For this reason, fans have been used in various electronic devices. However, depending on how the fan is used, the air flow is reduced, noise is caused, and a failure is likely to occur. On the other hand, the value of the product may be significantly reduced. Therefore, proper design related to the fan is extremely important.

[0021]

Generally, the static pressure and air flow characteristics of a fan used to cool heat generated by an electronic device are represented by a characteristic RA shown in FIG. When this fan is mounted on an electronic device having the fluid resistance characteristic RB shown in FIG. 3 and ventilation is performed, the fan actually operates at a point RC in FIG. The static pressure / air volume characteristic RA is determined at the time of designing the fan at the time of manufacture and is generally disclosed by a data source from a supplier. The fluid resistance characteristic RB can be simulated by the following equation (1), assuming that the electric device (apparatus) is a resistor.

P = R · Q ² ··· (1) where P: pressure, Q: air volume, R: resistance. That is, the fluid resistance characteristic RB can be approximated by a quadratic curve.
If the relationship between the pressure (difference) and the air volume is determined, the characteristics can be determined. In thermal analysis of an electronic device, it is most important to accurately obtain an operating point as shown by a point RC in FIG. 3 and to correctly estimate a fan air volume. However, in the conventional thermal analysis device, this estimation mechanism was not sufficient.

The noise of the fan differs depending on the operating point. FIG. 4 shows various characteristics of the fan. It can be seen that the noise level varies depending on the air volume. The conventional thermal analyzer could not estimate this fan noise.

Estimating the life of the fan is important in the initial design. In the forced air cooling device, a failure of the fan may immediately lead to a failure of the device. The life of a fan depends on its ambient temperature; the higher the temperature, the shorter the life. Therefore, it is necessary to predict the life of the fan, and to determine whether the life of the fan is set longer than the design life of the apparatus or whether the replacement of parts in the event of a fan failure is included in the design at an early stage of the design. The conventional thermal analyzer could not obtain enough information to make this determination.

In some cases, a forced air-cooled electronic device has a fan attached to both the suction port (air intake port) and the discharge port. In the push-pull type fan, when the static pressure-air volume characteristics of both fans are different, they affect each other to determine an operating point. This phenomenon was complicated, and could not be analyzed by a conventional thermal analyzer.

An object of the present invention is to provide a thermal analysis apparatus for electronic equipment which can easily perform thermal analysis in consideration of fan characteristics.

[0027]

According to one aspect of the present invention, there is provided a thermal analysis apparatus for electronic equipment which supports a design for measures against heat generation of electronic equipment using a computer. Storage means for storing characteristic data of the fan that determines the relationship with the air volume; and a pressure difference between fluids on both sides of the fan provided in the electronic device, and based on the determined pressure difference and the characteristic data of the fan. Calculating means for determining the operating flow rate of the fan, and calculating the flow rate of the fluid around the fan based on the determined operating flow rate.

According to the first aspect of the present invention, the characteristic data of the fan is stored in the storage means. The characteristic data of the fan defines the relationship between the static pressure and the air flow, and the static pressure refers to the pressure difference between both sides of the fan (the intake side and the exhaust side of the fluid). First, the calculating means obtains the pressure difference between the fluids on both sides of the fan. Next, the calculating means obtains the operating flow rate of the fan based on the pressure difference and the characteristic data of the fan. The fluid pressure difference on both sides of the fan can correspond to the static pressure, and if the static pressure is determined, the air volume can be determined. Therefore, the obtained air volume is made to correspond to the operation flow rate. Next, the calculating means obtains the flow rate of the fluid around the fan. That is, since the operating flow rate of the fan has been determined, the flow rate of the fluid around the fan can be determined from the operating flow rate.

According to a second aspect of the present invention, in the first aspect of the present invention, there is provided a calculating means for calculating an operating point of the fan based on an operating flow rate of the fan and a pressure difference between fluids on both sides of the fan. It is further characterized by being provided.

According to the second aspect of the present invention, the calculating means makes the operating flow rate of the fan determined by the calculating means correspond to the air volume of the fan, and makes the pressure difference between the fluids on both sides of the fan correspond to the static pressure of the fan. . Next, the calculating means determines the operating point of the fan by referring to the characteristic data of the fan from the obtained values of the static pressure and the air volume.

According to a third aspect of the present invention, in the second aspect of the present invention, there is further provided a display means for displaying a characteristic curve representing a relationship between a static pressure and an air flow based on the characteristic data of the fan, and the operating point. It is characterized by having.

According to the third aspect of the present invention, the display means displays a characteristic curve based on the characteristic data of the fan, and displays the operating point of the fan on the curve. Thereby, the displayed operating point can be easily confirmed, and the operator can accurately grasp the operating state of the fan.

According to a fourth aspect of the present invention, in the first aspect of the present invention, the noise characteristic data of the fan, which defines the relationship between the operating flow rate and the noise level of the fan, is stored. It is characterized by further comprising noise data storage means and estimating means for estimating the noise level of the fan based on the operation flow rate of the fan and noise characteristic data of the fan.

According to the fourth aspect of the present invention, the noise characteristic data of the fan is stored in the noise data storage means. The fan noise characteristic data defines the relationship between the fan operation flow rate and the fan noise level. The estimating means estimates the noise level of the fan according to the value of the operating flow rate of the fan based on the noise characteristic data of the fan from the operating flow rate of the fan obtained by the calculating means. In this way, since the noise level of the fan is estimated from the operating flow rate of the fan,
It is possible to analyze the noise level of the fan.

According to a fifth aspect of the present invention, in the first aspect of the present invention, the temperature information of the fluid on both sides of the fan is obtained, and the ambient temperature of the fan is determined based on the obtained temperature information. Temperature calculating means for calculating the relationship between the ambient temperature and the life of the fan, and life data storage means for storing life characteristic data of the fan, based on the ambient temperature of the fan and the life characteristic data of the fan. Predicting means for predicting the life of the fan.

According to the fifth aspect of the present invention, the temperature calculation means obtains an average temperature value from the temperature information on both sides of the fan and sets the obtained value as the ambient temperature of the fan. The life data storage means stores life characteristic data of the fan. The life characteristic data of the fan defines the relationship between the ambient temperature of the fan and the life of the fan. The predicting means predicts the life of the fan based on the fan life characteristic data from the value of the ambient temperature of the fan obtained by the temperature calculating means. As described above, since the life of the fan is predicted from the ambient temperature of the fan, it is possible to analyze the life of the fan.

According to a sixth aspect of the present invention, in the first aspect of the present invention, the operation range determined by the characteristic data of the fan is defined as a normal use range, and the fan within the normal use range is determined. Calculating means for calculating characteristic data of the fan outside the normal use range based on the characteristic data, and calculating an operating point of the fan based on the obtained characteristic data of the fan outside the normal use range. It is characterized by.

In the invention according to claim 6, the calculating means includes:
If the fan is operating outside normal use, for example,
When the static pressure of the fan is negative, data of the fan operation flow rate corresponding to the negative static pressure is inserted into the characteristic data of the fan. Based on the fan characteristic data obtained as a result, the operating point of the fan operating at a negative static pressure (ie,
(The value of the static pressure and the value of the operating flow rate according to the static pressure).

According to a seventh aspect of the present invention, in accordance with the sixth aspect of the present invention, there is provided an abnormal operation fan data storing means for storing information regarding the operating point calculated by the calculating means as abnormal operation fan data; And a warning display unit for displaying a warning of an abnormal operation of the fan when the information is stored in the data storage unit.

According to the seventh aspect of the present invention, since the fan operating at the negative static pressure is in an abnormal operation state, the warning display means displays information on the operating point of the abnormal operation fan obtained by the calculation means ( Static pressure value, air flow value, fan identification name, etc.)
Display a warning according to the stored information. This allows
The operator can reliably grasp the abnormal operation state of the fan.

[0041]

Embodiments of the present invention will be described below in detail with reference to the drawings.

(First Embodiment) FIG. 1 shows a configuration of a thermal analysis apparatus according to a first embodiment of the present invention. In the present embodiment, the present invention is applied to a thermal analysis device. Since the thermal analyzer of the present embodiment has substantially the same configuration as the above-described conventional thermal analyzer, the same portions are denoted by the same reference numerals, and detailed description is omitted.

The thermal analysis apparatus according to the present embodiment includes an arithmetic processing section 6A. The arithmetic processing section 6A further includes a fan characteristic calculation processing section 63 in the arithmetic processing section 6 of the conventional thermal analysis apparatus. Things. Here, the arithmetic processing unit 6A includes a ventilation circuit arithmetic processing unit 61, a fan characteristic calculation processing unit 63, and a heat circuit arithmetic processing unit 62, and the ventilation circuit arithmetic processing unit 61, the fan characteristic calculation processing unit 63, The thermal circuit operation processing unit 62 is connected in order. Further, in the present embodiment, a library data storage unit 7A is provided, and the library data storage unit 7A stores the fan characteristic data 72 so that the fan characteristic data 72 is transmitted to the fan characteristic calculation processing unit 63 of the arithmetic processing unit 6A. It is connected to the calculation processing unit 63.

Next, the operation of the present embodiment will be described. In the thermal analysis device according to the present embodiment, the processing routine of FIG. 5 is executed.

As shown in FIG. 5, in the processing of the ventilation circuit arithmetic processing section 61 of the arithmetic processing section 6A, first, a node pressure is assumed (step 102), and a flow rate is obtained by using a predetermined pressure loss equation (step 102). 104), a predetermined pressure correction formula is read, and a corrected pressure is determined using the pressure correction formula (step 106), and then the pressure of the node is corrected (step 108). Subsequently, the flow rate correction processing of the fan unit (Step 110) is executed. Then, the processing from step 104 onward is repeated until the residual error becomes smaller than the allowable value (step 112). At this time, if the residual error is equal to or larger than the allowable value, the pressure update pressure loss coefficient is corrected (step 112). When the residual error becomes smaller than the allowable value, the process of the thermal circuit arithmetic processing unit 62 is subsequently executed.

Next, the processing of step 110 will be described in detail. In step 110 of FIG. 5, the processing routine shown in FIG. 7 is executed. First, a fan element in the network data 43 is searched and extracted (step 302). Here, the network data 43 is composed of elements such as fluid resistance and heat transfer resistance and boundary conditions such as pressure fixing, flow rate fixing, temperature fixing, heat quantity fixing and the like. Although the fan is a kind of boundary condition, it is a special boundary condition in which the pressure and the flow rate are given in a functional relationship, so the three-dimensional shape data processing unit 31, the area division processing unit 51, and the ventilation circuit generation unit 52
It is identified as a special element and is identified and stored in the network data 43. For this reason, the fan element can be searched relatively easily.

When the fan element is extracted, the pressure data of the nodes constituting both ends of the fan element are read (step 304). The node pressures read here are assumed to be Pl and P2, respectively. FIG. 8 shows the relationship between the fan element F and the nodes A and B at both ends thereof. As shown in the figure, a fan element F is included in an adjacent fluid area Area, which is a small area divided by the area division processing unit 51. In each fluid area Area, a ventilation circuit connected by a fluid resistance R is generated, and nodes A,
B.

Next, a fan operation flow rate is calculated from the fan characteristic data 72 (step 306). As the fan characteristic data 72, as shown in FIG. 9, a plurality of data in which the static pressure and the air volume correspond are stored. In addition, FIG.
It shows fan characteristics indicating the relationship between static pressure and air flow including these data. The pressure difference before and after the fan element is obtained from the pressures Pl and P2 (Pl-P2). This pressure difference (P
Using l-P2) as the static pressure, the operating flow rate of the fan is estimated. That is, the fan characteristic data 72 indicates the correspondence between the static pressure and the air flow. The air flow corresponding to the static pressure is obtained, and the obtained air flow is estimated as the operating flow rate Q. This process is
As shown in FIG. 10, it can be expressed by obtaining the air volume on the fan characteristic SA with respect to the static pressure. In this case, by performing linear interpolation or spline interpolation on the fan characteristic data 72, the operating flow rate Q of the fan can be obtained with higher accuracy.

The resulting fan operation flow rate Q is given to nodes A and B at both ends of the fan element as boundary conditions (step 308). In this case, +
Q, −Q is given to the suction port side.

After the above processing is executed, as shown in FIG. 5, until the residual error becomes less than the allowable value (step 11).
4) If repeated, the pressure difference between the nodes before and after the fan element (P
The relationship between 1-P2) and the fan operation flow rate Q always exists on the fan characteristic curve, and analysis in consideration of the fan characteristic becomes possible.

As described above, in the thermal analysis apparatus according to the present embodiment, by providing the fan characteristic calculation processing unit 63, it is possible to calculate the flow rate accurately in consideration of the fan characteristic, and to force the thermal analysis apparatus. The analysis accuracy when predicting the temperature of the air-cooled device can be greatly improved. In addition, by accurately predicting the operating point (operating flow rate and static pressure) of the fan, it is possible to verify whether the fan operates stably without causing a failure such as surging.

(Second Embodiment) FIG. 11 shows the second embodiment.
1 shows a configuration of a thermal analysis device according to the embodiment. Note that the thermal analysis device of the present embodiment has substantially the same configuration as the thermal analysis device of the first embodiment, and thus the same portions are denoted by the same reference numerals and detailed description thereof will be omitted.

The thermal analysis apparatus according to the present embodiment includes an input / output processing unit 3B. The input / output processing unit 3B includes a three-dimensional shape data processing unit 31, a result display processing unit 32, and a fan operating point calculation processing unit 33. And a fan operating point display processing unit 34. The fan operating point calculation processing unit 33 is connected to the fan operating point display processing unit 34, and the fan operating point display processing unit 3
4 is connected to the input device 2. Further, the data storage unit 4 is connected to the input / output processing unit 3 so that various data stored in the data storage unit 4 are also input to the fan operating point calculation processing unit 33.

In this embodiment, the library data storage unit 7B is provided.
B is connected to the fan operating point calculation processing unit 33 so that the fan characteristic data 72 is transmitted to the fan operating point calculation processing unit 33 of the input / output processing unit 3B.

Next, the operation of the present embodiment will be described. In the thermal analysis device according to the present embodiment, the processing routine of FIG. 12 is executed.

As shown in FIG. 12, the fan operating point calculation processing section 33 first extracts fan elements from the network data 43 (step 402). Next, the pressure at the nodes at both ends of the fan element is read (step 404), and the fan flow rate is calculated with reference to the fan characteristic data 72 (step 406). The above processing is performed in step 3 of FIG.
02 to step 306, but the processing in the fan operating point calculation processing section 33 is executed after the processing in the arithmetic processing section 6A is completed.

Next, the fan operating point calculation processing section 33 stores data of the pressure difference ΔP before and after the fan and the flow rate Q of the fan (step 408).

Thereafter, the data obtained in step 408 is output to the fan operating point display processing section 34. In the fan operating point display processing section 34, the processing routine of FIG. 13 is executed. As shown in FIG. 13, the fan operating point display processing section first displays a fan characteristic curve on a screen (step 502). Next, the operating point is displayed on the characteristic curve based on the operating point information (the pressure difference ΔP before and after the fan and the fan flow rate Q) output from the fan operating point calculation processing unit 33 (step 504). If a quadratic curve passing through the operating point displayed on the characteristic curve is displayed, the ventilation characteristics of the device can be approximately expressed. FIG. 14 shows an example of the characteristic curve displayed on the screen including the display of the ventilation characteristics of the device. In the drawing, a fan characteristic curve is indicated by a curve Sa, a ventilation characteristic of the device is indicated by a curve Sb, and an operating point is indicated by a mark Sc. Here, when there is no operating point mark Sc on the fan characteristic curve on the screen, it means that the operating point calculation is not sufficiently converged. Therefore, the above-mentioned characteristic curve can also be used for evaluating the calculation convergence state.

As described above, in the thermal analyzer according to the present embodiment, the fan operates at the efficient operating point by providing the fan operating point display processing unit 34 and the fan operating point calculation processing unit 33. Can be easily determined. Further, it is possible to visually determine whether or not the operating point calculation has correctly converged on the screen.

(Third Embodiment) FIG. 15 shows the third embodiment.
2 shows a thermal analysis apparatus according to the embodiment. Note that the thermal analysis device of the present embodiment has substantially the same configuration as the thermal analysis device of the second embodiment, and therefore, the same portions are denoted by the same reference numerals and detailed description thereof will be omitted.

The thermal analysis apparatus according to the present embodiment includes an input / output processing unit 3C. The input / output processing unit 3C includes a three-dimensional shape data processing unit 31, a result display processing unit 32, and a fan operating point calculation processing unit 33. , A fan operating point display processing unit 34 and a fan noise calculation processing unit 35. The fan noise calculation processing unit 35 is connected to the fan operating point calculation processing unit 33 and the input device 2.

Further, in the present embodiment, a library data storage section 7C is provided.
C is connected to the fan noise calculation processing unit 35 so that the fan noise characteristic data 75 is transmitted to the fan noise calculation processing unit 35 of the input / output processing unit 3C.

Next, the operation of the present embodiment will be described. The operation of the fan noise characteristic data 75, the fan noise calculation processing unit 35, and the fan noise characteristic data 75 of the thermal analysis device according to the present embodiment will be described in detail.

First, the fan noise characteristic data 75 will be described. The noise of the fan generally depends on the air flow and has a noise characteristic as shown in FIG. The noise increases when the static pressure is high, but also increases when the air volume is high. The noise is minimized when a moderate load is applied to the fan. In the fan noise characteristic data 75, a part of the data of the characteristic curve is recorded in a table format in a combination of "air volume-noise level". That is, as in the record of the characteristic data of the fan shown in FIG. 9, the correspondence between the air volume and the noise level is stored as the fan noise characteristic data 75.

In the second embodiment, when the fan operating point calculation processing section 33 calculates the operating point and outputs the operating flow rate Q, the result is sent to the fan noise calculation processing section 35. The fan noise calculation processing unit 35 searches for fan noise data based on the operating flow rate Q, performs interpolation processing, and calculates a noise level. The calculated noise level is displayed on the display device 1.
Is displayed on the screen.

As described above, in the thermal analysis apparatus according to the present embodiment, the fan noise characteristic data 75 is stored in the library data storage section 7C, and the fan noise calculation processing section 35 is provided in the input / output processing section 3C. This makes it possible to estimate and predict the fan noise, thereby facilitating silent design of the electronic device.

(Fourth Embodiment) FIG. 16 shows the fourth embodiment.
2 shows a thermal analysis apparatus according to the embodiment. Note that the thermal analysis device of the present embodiment has substantially the same configuration as the thermal analysis device of the first embodiment, and thus the same portions are denoted by the same reference numerals and detailed description thereof will be omitted.

The thermal analyzer according to the present embodiment includes an input / output processing unit 3D. The input / output processing unit 3D includes a three-dimensional shape data processing unit 31, a result display processing unit 32, a fan life calculation processing unit 36, A fan temperature calculation processing unit 37 is provided.
The fan life calculation processing unit 36 is connected to the fan temperature calculation unit 37 and the input device 2. The data storage unit 4
Is connected to the input / output processing unit 3 so that various data stored in the data storage unit 4 is also input to the fan temperature calculation processing unit 37.

Further, in the present embodiment, a library data storage section 7D is provided.
D is connected to the fan life calculation processing unit 36 so that the fan life characteristic data 76 is transmitted to the fan life calculation processing unit 36 of the input / output processing unit 3D.

Next, the operation of the present embodiment will be described. The operation of the fan life characteristic data 76 and the fan life calculation processing unit 36 and the fan temperature calculation processing unit 37 of the thermal analysis device according to the present embodiment will be described in detail.

First, the fan life characteristic data 76 will be described. Fan life generally depends on ambient temperature,
It has characteristics as shown in FIG. Since the service life is sharply shortened when the temperature is high, the fan itself must be cooled and kept at a certain temperature or lower. Fan life characteristic data 76
In the table, a plurality of correlation data of the temperature and the life are stored in a table format in a combination of "temperature-life level". That is, similarly to the record of the fan characteristic data shown in FIG. 9, the correlation between the temperature and the life is stored as the fan life characteristic data 76.

Next, the operation of the fan life calculation processing section 36 and the fan temperature calculation processing section 37 will be described. When the processing of the arithmetic processing unit 6A ends, the result is stored in the data storage unit 4 as the pressure air volume data 44 and the temperature data 45. In the fan temperature calculation processing section 37, the processing routine of FIG. 18 is executed. As shown in FIG. 18, in the processing of the fan temperature calculation processing unit 37, first, the network data 4
3 are extracted (step 602). Next, the temperature data 45 is read based on the node coordinate data 42 at both ends of the fan element (step 604). Here, let T1 and T2 be the node temperatures at both ends of the fan. Next, the ambient temperature Tf of the fan is calculated (step 606). Normally, the fan ambient temperature Tf is obtained by the following equation (2) as an average value of the node temperatures at both ends.

Tf = (T1 + T2) / 2 (2) The obtained Tf is stored and held in the fan temperature calculation processing unit 37 (step 608), and is output to the fan life calculation processing unit 36.

The processing routine shown in FIG. 19 is executed in the fan life calculation processing section 36. Fan life calculation processing unit 36
Then, the fan ambient temperature Tf is obtained (step 70).
2), search the fan life characteristic data 76 based on it,
After performing the interpolation calculation, the life is calculated (step 70).
4). The calculated life is displayed on the screen of the display device 1 (step 706). Therefore, the operator can recognize the life of the fan only by looking at the display device 1.

As described above, in the thermal analysis apparatus according to the present embodiment, the life of the fan is reduced by providing the storage unit for the fan life data 76, the fan life calculation processing unit 36, and the fan temperature calculation processing unit 37. Can be predicted,
More reliable electronic device design can be easily performed.

(Fifth Embodiment) FIG. 20 shows the fifth embodiment.
2 shows a thermal analysis apparatus according to the embodiment. Note that the thermal analysis device of the present embodiment has substantially the same configuration as the thermal analysis device of the first embodiment, and thus the same portions are denoted by the same reference numerals and detailed description thereof will be omitted.

[0077] The thermal analysis apparatus of the present embodiment includes an arithmetic processing unit 6B. The arithmetic processing unit 6B includes a ventilation circuit arithmetic processing unit 61, a fan characteristic calculation processing unit 63, a thermal circuit arithmetic processing unit 62, and a fan special operation processing unit 64. The calculation processing unit 63 and the thermal circuit calculation processing unit 62 are connected in order. The fan characteristic calculation processing unit 63 includes a fan special operation processing unit 64
Is connected.

In the sound embodiment, a library data storage section 7E is provided, and the fan special operation processing section 64 is provided so that the fan characteristic data 72 is also transmitted to the fan special operation processing section 64 of the arithmetic processing section 6B. 64.

Next, the operation of the present embodiment will be described. The operation of the fan special operation processing unit 64 of the thermal analysis device according to the present embodiment will be described in detail.

First, the features of the push-pull fan will be described. FIG. 22 schematically shows a push-pull type fan. The fan A installed on one side of the housing is a fan that discharges air inside the housing to the outside (in the direction of the arrow u in FIG. 22). The other fan B is a suction fan that takes in outside air into the housing (the direction of the arrow w in FIG. 22). Such a forced air cooling system in which fans are provided on both the suction side and the discharge side is called a push-pull type fan mounting system. In the push-pull type fan mounting system, fans interact with each other,
A complex phenomenon occurs. If there is no ventilation hole in the housing other than the fan portion, the air volume passing through the fan A and the air volume passing through the fan B must be equal. If the fan A has a smaller air volume than the fan B, the fan A operates while receiving a pressure (wind pressure) from the fan B. On the other hand, when viewed from the fan B, the fan A becomes a load as a fluid resistance.

With the processing of the fan characteristic calculation processing section 63 alone (see FIGS. 5 and 7), when the push-pull type fan is mounted, the calculation does not converge, so that it is difficult to analyze. This is because the existence range of the operating point of the fan becomes a negative static pressure range. Normally, fan characteristic data is not measured in this range. For this reason, it is also difficult to register as library data.

For example, in the push-pull type fan shown in FIG. 22, when the air volume of the fan A is smaller than the air volume of the fan B, a difference is generated between the pressure on the discharge side of the fan A and the pressure on the suction side of the fan B. A is in a state of operating while pressure (wind pressure) is applied from the fan B. As a result, the fan A operates in a state where the pressure on the suction side is higher than the pressure on the discharge side, that is, in a state where the static pressure is negative, and the curve Ka as shown in FIG.
The characteristic of is expressed.

In the fan section flow rate correction processing in the case where the fan special operation processing section 64 is provided, the processing routine of FIG. 21 is executed. In the fan section flow rate correction processing, the processing up to the reading processing of the pressure at the both ends nodes of the fan element (step 80
Steps 2 to 804) are the same as those described in the first embodiment. This embodiment is different from the first embodiment in that the node pressures Pl and P2 are passed to the fan special operation processing unit 64 at this stage. After the process of reading the pressure at the both ends of the fan element (step 804), the magnitudes of the node pressures Pl and P2 are compared (step 806). At this time, if the pressure on the suction port side of the fan is lower than the pressure on the discharge port side of the fan, the same processing (steps 810 to 812) as in the first embodiment is executed. Conversely, when the suction port side pressure of the fan is higher than the discharge port side pressure of the fan, the fan special operation processing section 64 executes fan static pressure / flow rate extrapolation calculation processing (step 808). In this process, using data in a normal operating range, data outside the range is obtained, and then an operating point is obtained. That is, FIG.
As shown in (A), the static pressure / air flow curve of the fan is extrapolated (characteristic Kc), and the static pressure is estimated even in a negative range to calculate the fan operating point. Further, the obtained result is given as a boundary condition to both end nodes of the fan element (step 812). By performing the above processing, the operating point can be correctly obtained even if the fan operates under special conditions.

As described above, in the thermal analysis apparatus according to the present embodiment, by providing the fan special operation processing section 64, a solution can be stably obtained even when a push-pull type fan is used. It becomes possible.

(Sixth Embodiment) FIG. 24 shows the sixth embodiment.
2 shows a thermal analysis apparatus according to the embodiment. Note that the thermal analyzer of the present embodiment has substantially the same configuration as the thermal analyzer of the fifth embodiment, and thus the same portions are denoted by the same reference numerals and detailed description thereof will not be repeated.

The thermal analyzer of this embodiment has an input / output processing unit 3E. The input / output processing unit 3E includes a three-dimensional shape data processing unit 31, a result display processing unit 32, and an abnormal operation fan display unit 38. Have. The abnormal operation fan display section 38 is connected to the input device 2.

The thermal analysis apparatus according to the present embodiment includes a data storage unit 4A. The data storage unit 4A stores the shape data 41, the node coordinate data 42, and the network data 4A.
3, a storage area for storing pressure air volume data 44, temperature data 45, and abnormal operation fan data 46. The data storage unit 4A is connected to the input / output processing unit 3E so that various data stored in the data storage unit 4A are input to the result display processing unit 32 and the abnormal operation fan display unit 38. Further, the fan special operation processing unit 64 of the arithmetic processing unit 6C is connected to the data storage unit 4A so that the processing result is stored as the abnormal operation fan data 46.

Next, the operation of the present embodiment will be described. The operation of the fan special operation processing unit 64, the abnormal operation fan display unit 38, and the abnormal operation fan data 46 of the thermal analysis device according to the present embodiment will be described in detail.

As described in the fifth embodiment, the fan characteristic calculation processing section 63 compares the node pressures at both ends of the fan element. If the static pressure of the fan is negative, the processing is performed by the fan special operation calculation section 64. Moved to Here, a fan having an operating point at which the static pressure of the fan becomes negative has a high possibility of abnormal operation. The identification name of the fan element, the operation air volume, and the operation static pressure are stored and held in the abnormal operation fan data 46 at the stage when the processing is transferred to the fan special operation calculation unit 64. This data is cleared at each iteration. As a result, when the processing of the arithmetic processing unit 6C ends, the latest abnormal operation fan data 46 is stored in the data storage unit 4A.

The abnormal operation fan display section 38 reads the abnormal operation fan data 46, processes the data such as pressure, air volume, and temperature as the calculation results into various distribution display formats such as contour diagrams and vector diagrams, and displays the processed data. Displayed on device 1. For example, as shown in FIG. 25, the abnormal operation fan is visually displayed in color on the shape display screen. The numerical value of the static pressure difference is displayed near the fan on the shape display screen. In addition, various methods such as visually displaying a warning message in the message area are conceivable.

As described above, the thermal analysis apparatus according to the present embodiment is provided with the abnormal operation fan display section 38 and stores and stores the abnormal operation fan data 46, whereby the abnormal operation of the fan can be reliably detected. The cooling system can be designed with high reliability.

Although the first to sixth embodiments have been described based on the node method, the present invention can be applied to other analysis methods such as the finite volume method, the difference method, and the finite element method. Things. As a result of the analysis,
It is possible to output pressure, air volume (wind speed), and temperature as numerical data, and the present invention can be applied to all models as long as the fans are identified and managed in the analysis model.

[0093]

As described above, according to the present invention, the flow rate of the fluid around the fan is corrected using the operating flow rate of the fan calculated based on the pressure difference of the fluid around the fan. There is an excellent effect that it is possible to obtain a thermal analysis device for electronic equipment that can easily perform thermal analysis in consideration of fan characteristics.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a thermal analysis device for electronic equipment according to a first embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a conventional thermal analysis device.

FIG. 3 is a diagram showing static pressure / air volume characteristics of a fan.

FIG. 4 is a diagram showing characteristics of a fan.

FIG. 5 is a flowchart showing a conventional arithmetic processing routine.

FIG. 6 is a flowchart showing an arithmetic processing routine of the present invention.

FIG. 7 is a flowchart showing a fan unit flow rate correction processing routine.

FIG. 8 is a schematic diagram showing a fan element and nodes at both ends thereof.

FIG. 9 is a diagram showing an example of a fan characteristic data record.

FIG. 10 is a diagram showing a procedure for obtaining a flow rate from static pressures P1 and P2 of a fan.

FIG. 11 is a schematic configuration diagram of a thermal analysis device for electronic equipment according to a second embodiment of the present invention.

FIG. 12 is a flowchart illustrating a processing routine of a fan operating point calculation processing unit.

FIG. 13 is a flowchart illustrating a processing routine of a fan operating point display processing unit.

FIG. 14 is a diagram showing an example of a fan operating point display screen.

FIG. 15 is a schematic configuration diagram of a thermal analysis device for electronic equipment according to a third embodiment of the present invention.

FIG. 16 is a schematic configuration diagram of a thermal analysis device for electronic equipment according to a fourth embodiment of the present invention.

FIG. 17 is a diagram showing a relationship between fan life and temperature.

FIG. 18 is a flowchart illustrating a processing routine of a fan temperature calculation processing unit.

FIG. 19 is a flowchart illustrating a processing routine of a fan life calculation processing unit.

FIG. 20 is a schematic configuration diagram of a thermal analysis device for electronic equipment according to a fifth embodiment of the present invention.

FIG. 21 is a flowchart illustrating a fan unit flow rate correction processing routine according to a fifth embodiment.

FIG. 22 is a schematic diagram showing a push-pull fan.

FIG. 23A is a diagram for illustrating an operating range of a fan having a negative static pressure, and FIG. 23B is a diagram illustrating characteristics of a fan having a large air volume and a fan having a small air volume.

FIG. 24 is a schematic configuration diagram of a thermal analyzer for electronic equipment according to a sixth embodiment of the present invention.

FIG. 25 is a diagram illustrating a screen display example of the abnormal operation fan display unit according to the sixth embodiment.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 display device 2 input device 3 input / output processing unit 4 data storage unit 5 network data generation processing unit 6 operation processing unit 7 library data storage unit 61 ventilation circuit operation processing unit 62 thermal circuit operation processing unit 63 fan characteristic calculation processing unit 72 fan Characteristic data 33 Fan operating point calculation processing unit 34 Fan operating point display processing unit 35 Fan noise calculation processing unit 36 Fan life calculation processing unit 37 Fan temperature calculation processing unit 75 Fan noise characteristic data 76 Fan life characteristic data 64 Fan special operation processing unit 38 Abnormal operation fan display section 46 Abnormal operation fan data

Claims (7)

[Claims] 1. A thermal analysis device for electronic equipment which supports design of measures against heat generation of electronic equipment using a computer, comprising: storage means for storing characteristic data of a fan defining a relationship between static pressure and air flow; The pressure difference between the fluids on both sides of the fan provided in the electronic device is determined, the operating flow rate of the fan is determined based on the determined pressure difference and the characteristic data of the fan, and the operating flow rate around the fan is determined based on the determined operating flow rate. A thermal analysis device for electronic equipment, comprising: a calculation means for determining a flow rate of a fluid. 2. The electronic device according to claim 1, further comprising calculating means for calculating an operating point of the fan based on an operating flow rate of the fan and a pressure difference between fluids on both sides of the fan. Thermal analysis equipment for equipment. 3. The electronic apparatus according to claim 2, further comprising a display unit for displaying a characteristic curve representing a relationship between a static pressure and an air flow based on characteristic data of the fan, and the operating point. For thermal analysis. 4. A noise data storage means for storing noise characteristic data of a fan which defines a relationship between an operation flow rate and a noise level of the fan, and the noise data storage means based on the operation flow rate of the fan and the noise characteristic data of the fan. 4. The thermal analysis apparatus for an electronic device according to claim 1, further comprising: an estimating unit configured to estimate a noise level of the fan. 5. Obtaining temperature information of fluid on both sides of the fan,
Temperature calculation means for calculating the ambient temperature of the fan based on the obtained temperature information; life data storage means for storing life characteristic data of the fan that defines a relationship between the ambient temperature and the life of the fan; The thermal analysis apparatus for an electronic device according to claim 1, further comprising: a prediction unit configured to predict a life of the fan based on ambient temperature and life characteristic data of the fan. 6. An operating range determined by the characteristic data of the fan is defined as a normal use range, and the characteristic data of the fan outside the normal use range is determined based on the characteristic data of the fan within the normal use range. 2. The apparatus according to claim 1, further comprising a calculating unit configured to calculate an operating point of the fan based on characteristic data of the fan outside the normal use range.
The thermal analysis device for an electronic device according to any one of claims 1 to 5. 7. An abnormal operation fan data storage means for storing information on the operating point calculated by said calculation means as abnormal operation fan data, and when the information is stored in the abnormal operation fan data storage means, 7. The thermal analysis apparatus for electronic equipment according to claim 6, further comprising a warning display unit for displaying an operation abnormality warning.