CN103900401B - Finned tube radiator with variable raised density - Google Patents

Abstract

The invention provides a finned tube radiator which comprises finned tubes, wherein each finned tube comprises a circular base tube, a first fin, a second fin, a third fin and a fourth fin, a first connecting piece is arranged between the first fin and the second fin, a second connecting piece is arranged between the third fin and the fourth fin, bulges are arranged inside the base tube, and the distribution density of the bulges is gradually increased along the flowing direction of fluid. The structure of the finned tube is optimized, heat exchange in the fluid flowing direction is enhanced, and the heat exchange efficiency is maximized, so that energy is saved, and the purposes of environmental protection and energy saving are achieved.

Description

A Finned Tube Radiator with Varying Protrusion Density

technical field

The invention belongs to the field of heat exchangers, in particular to a finned tube radiator for heating.

Background technique

The heat source of home heating terminal equipment is generally urban central heating, self-built boiler rooms in residential areas, household wall-hung boilers, etc., which dissipate heat through heat conduction, radiation, and convection to increase the temperature of the room.

Among the radiators, finned tube radiators are widely used at present. The heat dissipation area can be enlarged and the heat exchange effect can be enhanced through the fins. However, the radiator type of the finned tubes and the setting of the finned tube parameters all affect the cooling effect. Good or bad, and in the current situation of energy crisis, there is an urgent need to save energy and meet the sustainable development of society. Maximize thermal efficiency to save energy and achieve the purpose of environmental protection and energy saving.

Contents of the invention

The technical problem to be solved by the present invention is to provide a new circular arc type closed finned tube radiator.

In order to achieve the above object, the technical scheme of the present invention is as follows:

A finned tube radiator with a closed structure, comprising an upper header, a lower header and a finned tube connecting the upper header and the lower header, the finned tube includes a circular base tube and a first fin, The second fin, the first fin and the second fin are arranged on the outside of the base pipe and the extension lines of the first fin and the second fin intersect the central axis of the base pipe where the center of circle of the base pipe is located, and the first fin The fin and the second fin are mirror-symmetrical along the first plane passing through the central axis of the base tube; the finned tube includes a third fin and a fourth fin, and the third fin and the fourth fin are along the first plane The two planes are respectively mirror-symmetrical to the first fin and the second fin, and the second plane is perpendicular to the first plane and passes through the central axis of the base pipe; a first fin is arranged between the first fin and the second fin. A connecting piece, a second connecting piece is arranged between the third fin and the fourth fin, the first connecting piece and the second connecting piece are arc-shaped metal plates; the first fin, the second fin and the adjacent The third fin and the fourth fin of the finned tube form a space; the central axis where the center of the circle of the arc-shaped metal plate is coincident with the central axis of the base tube; the base tube is a straight tube, and the adjacent The central axes of the base pipes are parallel to each other; the first fins of adjacent base pipes are parallel to each other.

The included angle between the first fin and the second fin is A, the length of the first fin and the second fin is L, the outer radius of the base pipe is R, and the fin along the axial direction of the base pipe is Chip height H, the relationship between the above four satisfies the following formula:

Sin(A/2)=a*(L/R) ² +b*(L/R)+c

H/(R*10)= e*Sin(A/2) ² -f*Sin(A/2)+h where the unit of A is angle, 60°<A<110°,

The size of L is mm, 12mm<L<80mm,

The unit of R is mm, 10mm<R<80mm,

The unit of H is mm, 800mm<R<1200mm,

a, b, c, e, f, h are coefficients, the range of a is 0.04-0.042, the range of b is 0.266-0.28, the range of c is 0.36-0.37, the range of e is 21-23, and the range of f is 44-45, h is 23-25.

The best results for the parameters are: a is 0.0412, b is 0.02715, c is 0.03628, e is 22, f is 44.37, and h is 23.86.

As a preference, the distance between the central axes of adjacent base pipes is S=d*(L+R)*sin(A/2), where d is 1.1-1.2.

The optimized result of d is 1.118.

The material of the base tube and the fins is aluminum alloy, and the mass percentage of the components of the aluminum alloy is as follows: 3.0% Cu, 1.9% Mg, 1.6% Ag, 0.6% Mn, 0.25% Zr, 0.3% Ce, 0.23 % Ti, 0.38% Si, and the rest is Al.

The inside of the base pipe is provided with an anti-corrosion layer, the outside of the base pipe is coated with a wear-resistant layer, and the thermal expansion coefficients of the anti-corrosion layer, the base pipe and the wear-resistant layer increase sequentially.

The radiator also includes a control system that controls the flow rate of water into the radiator according to the room temperature.

The control system includes: a temperature sensor, a flow controller and a central controller, the flow controller controls the flow rate entering the radiator; the temperature sensor is used to measure the indoor temperature, and when the indoor temperature reaches the first temperature, the central controller controls The flow controller reaches the first flow rate, when the indoor temperature reaches the second temperature higher than the first temperature, the central controller controls the flow controller to reach the second flow rate lower than the first flow rate, when the indoor temperature reaches the second temperature higher than the second temperature At the third temperature, the central controller controls the flow controller to reach the third flow rate lower than the second flow rate, and when the indoor temperature reaches the fourth temperature higher than the third temperature, the central controller controls the flow controller to reach the third flow rate lower than the second flow rate. The fourth flow rate of the three flow rates; when the indoor temperature reaches the fifth temperature higher than the fourth temperature, the central controller closes the flow controller to prevent water from entering the radiator.

The anti-corrosion layer is composed of the following components:

8.3% flake zinc powder, 8% aluminum oxide, 7.3% boric acid, 0.7% acrylic acid, 0.4% wetting and dispersing agent, 0.15% thickening agent, 0.23% defoaming agent, and the balance is water.

The wetting and dispersing agent is SA-20 in the Pingpingjia series, the thickener is selected from hydroxyethyl cellulose; the defoamer is selected from tributyl phosphate.

There are no fins in the parts near the upper and lower headers in the axial direction of the base pipe.

The length of the portion of the base pipe without fins near the lower header is greater than the length of the portion without fins near the upper fins.

The fluid flow area in the upper header gradually decreases along the fluid flow direction.

A deflector is arranged inside the upper header, and the deflector extends obliquely from the position of the inlet pipe of the radiator to the lower part of the upper header.

The upper wall surface of the upper header extends obliquely from the position of the radiator inlet pipe to the lower part of the upper header.

The shape of the deflector is a straight plate shape or a curved plate shape.

Compared with the prior art, the solar water heater of the present invention has the following advantages:

1) The present invention provides a new finned tube, and because the extension line of the fins of the finned tube coincides with the center of the base tube, the heat exchange effect is the best.

2) The present invention designs fins with different pipe diameters, different heights, and included angles through multiple tests to obtain an optimal fin optimization result, which is verified by tests, thus proving the accuracy of the results sex.

3) The high heat resistance and high thermal conductivity of the finned tube are improved through the reasonable distribution of the mass percentage of the components of the aluminum alloy.

4) The thermal expansion coefficients of the anti-corrosion layer, the base pipe and the wear-resistant layer increase sequentially to ensure that the expansion rate of each layer is the same when hot water is passed through, so as to ensure the tight combination of each layer and prevent falling off.

5) Through the control system, the flow rate of water entering the radiator is automatically controlled to keep the room temperature at a stable value.

6) By having no fins in the axial direction of the base tube near the upper header and the lower header, it is ensured that the air in the lower part of the base tube can smoothly enter the gap of the finned tube, achieving a good suction effect, and at the same time It can also ensure the upward convection of the air technology and increase the effect of convective heat transfer.

7) The length of the part without fins passing through the part of the base pipe near the lower header is greater than the length of the part without fins near the upper fins, which can increase the convection effect.

8) Through the gradual reduction of the flow area of the fluid in the upper header, the flow rate of the fluid is kept at the maximum and the heat transfer is enhanced.

Description of drawings

Fig. 1 is the schematic diagram of radiator of the present invention;

Fig. 2 is a schematic cross-sectional view of a finned tube;

Fig. 3 is the schematic diagram of radiator control system;

Fig. 4 is a schematic diagram viewed from the left side of Fig. 3;

Fig. 5 is a schematic diagram of a radiator with a deflector;

Fig. 6 is a schematic diagram of a radiator with a gradually shrinking cross-sectional area of the upper header.

The reference signs are as follows:

1. Upper header, 2. Part without fins in the base tube, 3. Lower header, 4. Finned tube, 5. Base tube, 6. First water fin, 7. Void part, 8. First connecting piece, 9. Second fin Sheet, 10 fourth fin, 11 third fin, 12 second connecting piece, 13 central controller, 14 flow controller, 15 temperature sensor, 16 temperature sensor, 17 radiator, 18 inlet pipe, 19 outlet pipe, 20 deflector, 21 upper surface of header.

Detailed ways

The specific embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings.

In this article, if there is no special explanation, when it comes to formulas, "/" means division, and "×" and "*" mean multiplication.

A finned tube radiator 17 with a closed structure, including an upper header 1, a lower header 3 and a finned tube 4 connecting the upper header 1 and the lower header 3, the finned tube 4 includes a circular base Tube 5 and first fin 6, second fin 9, first fin 6 and second fin 9 are arranged on the outside of base pipe 5 and the extension line of first fin 6 and second fin 9 intersects at The central axis of the substrate tube where the center of the substrate tube 5 is located, the first fin 6 and the second fin 9 are mirror-symmetrical along the first plane B passing through the central axis of the substrate tube; the finned tube includes a third fin 11 and the fourth fin 10, the third fin 11 and the fourth fin 10 are respectively mirror-symmetrical to the first fin 6 and the second fin 9 along the second plane C, and the second plane C is the same as the second plane C A plane B is vertical and passes through the central axis of the base pipe 5; the first connecting piece 8 is arranged between the first fin 6 and the second fin 9, and the third fin 11 and the fourth fin 10 The second connecting piece 12 is set, and the first connecting piece 8 and the second connecting piece 12 are arc-shaped metal plates; the central axis of the arc-shaped metal plate coincides with the central axis of the base pipe 5; the base pipe is a straight tubes, the central axes of the adjacent base tubes are parallel to each other.

Preferably, the first fins of adjacent base pipes are parallel to each other, which means that the second fins of adjacent base pipes are also parallel to each other. Similarly, the third fins and the fourth fins are also parallel to each other. This feature indicates that the finned tubes are aligned in the same direction.

It should be explained that, as shown in Figure 2, the central axis of the base pipe is a line formed by the collection of the center points on the cross-section of the base pipe 5, and the central axis of the arc-shaped metal plate is the arc-shaped metal plate on the cross-section. A line formed by the collection of center points of the plate. The coincidence of the central axis of the arc-shaped metal plate with the central axis of the base pipe 5 means that the arc-shaped metal plate and the base pipe are concentric circles on the cross section.

Preferably, all finned tubes are the same size.

Through the above arrangement, a gap part 7 is formed between the fin and the connecting piece, and the gap part 7 forms a chimney effect during convective heat exchange, which can enhance heat transfer.

The first fin, the second fin form a space with the third fin and the fourth fin of the adjacent fin tube, and the space forms a certain gap, which can form a chimney effect, enhance convection, and enhance heat transfer.

The included angle between the first fin 6 and the second fin 9 is A, the length of the first fin 6 and the second fin 9 is L, and the outer radius of the base pipe is R, of course, because of mirror image symmetry , the length of the third fin 11 and the fourth fin 10 is also L naturally. However, it has been found in practice that during the heat exchange process, if the included angle of the fins is too small, the heat exchange will be hindered, because if the included angle of the fins is too small, the distance between the first fin and the second fin will be too close, then The temperature boundary layer begins to overlap with the height of the base tube in the closed area, the gas temperature is close to the tube wall temperature and gradually approaches thermal saturation, the flow resistance increases, and eventually the heat transfer is deteriorated, and the advantages of the outer fins cannot be brought into play. For the same reason, with the continuous increase of the included angle, the distance between the connecting piece and the substrate pipe is closer, and the temperature boundary layer begins to overlap with the height of the substrate pipe in the closed area, and the gas temperature is close to that of the pipe. The wall temperature gradually approaches thermal saturation, the flow resistance increases, and eventually the heat transfer deteriorates, so the included angle has an optimal value.

For the fin length, if it is too long, it is because the heat of the base tube cannot reach the end of the fin in time or the effect is not obvious even if it is reached, if it is too short, the extended heat transfer area is too small to achieve a good heat transfer effect, so the height of the fins also has an optimum value.

For the distance between two finned tubes, first if the distance is too close or completely close, the space between the connecting pieces of the two finned tubes (see Figure 1) is too small, and the air cannot pass between the fins The gap between the finned tubes enters the gap formed between the finned tubes. At this time, the heat exchange can only rely on the air entering from the bottom of the radiator, which cannot achieve a good convective heat transfer effect. For the same reason, if the distance is too far, the finned tubes will The first, second, third, and fourth fins cannot form gaps for effective chimney effects, resulting in poor heat transfer effects, so an appropriate value is also required for the distance between the two finned tubes.

As shown in Figure 4, the height H of the fins along the axial direction of the base pipe 5 also needs to have an appropriate value. If the height of the fins is too high, it should be at the upper part of the fins, because the boundary layer is in the closed area As the direction of the height of the base pipes begins to overlap, the heat transfer will deteriorate. Similarly, if the height is too low, the heat transfer will not be fully utilized, thereby affecting the heat transfer effect.

Therefore, the present invention summarizes the optimal dimensional relationship of the finned tubes of the radiator through the test data of multiple radiators of different sizes. Because the finned tube also has three variables: angle A, fin length L, and fin height H, therefore, two dimensionless quantities sin(A/2), L/R, and H/R are introduced, where R is The radius of the base pipe is calculated in nearly 200 forms starting from the maximum heat dissipation in the heat exchange effect. The dimensional relationships described are as follows:

The included angle between the first fin and the second fin is A, the length of the first fin and the second fin is L, the outer radius of the base pipe is R, and the fin along the axial direction of the base pipe is Chip height H, the relationship between the above four satisfies the following formula:

Sin(A/2)=a×(L/R) ² +b×(L/R)+c

H/(R×10)= e×Sin(A/2) ² -f×Sin(A/2)+h where the unit of A is angle, 60°<A<110°,

The size of L is mm, 12mm<L<80mm,

The unit of R is mm, 10mm<R<80mm,

The unit of H is mm, 800mm<R<1200mm,

a, b, c, e, f, h are coefficients, the range of a is 0.04-0.042, the range of b is 0.266-0.28, the range of c is 0.36-0.37, the range of e is 21-23, and the range of f is 44-45, h is 23-25.

After calculating the results, the test is carried out. By calculating the boundary and intermediate values, the obtained results are basically consistent with the formula. The error is basically within 4%, the maximum relative error is not more than 6%, and the average error is 2%. ;

The best results of coefficient optimization are: a is 0.0412, b is 0.02715, c is 0.03628, e is 22, f is 44.37, and h is 23.86.

Preferably, the distance between the central axes of adjacent base pipes is S=d×(L+R)×sin(A/2), where d is 1.1-1.2.

As shown in Fig. 2, the distance between the central axes of adjacent substrate tubes is the distance between the centers of two substrate tubes on the cross section.

The optimized result of d is 1.118.

The material of the base tube and the fins is aluminum alloy, and the mass percentages of the components of the aluminum alloy are as follows: 3.0% Cu, 1.9% Mg, 1.6% Ag, 0.6% Mn, 0.25% Zr, 0.3% Ce, 0.23% Ti , 0.38% Si, and the rest is Al.

The manufacturing method of aluminum alloy is: vacuum metallurgical smelting, argon protection casting into a round billet, after homogenization treatment at 600 °C, hot extrusion at 400 °C into rods, and then after solid solution quenching at 580 °C, in 200°C for artificial aging treatment. The thermal conductivity is greater than 250W/(m*k).

The base tube and the fins can be manufactured in one piece or separately. The base tube and the fins can also be made of different materials. For example, the base tube is the aforementioned aluminum alloy, and the fins can be made of other alloys. as follows:

The mass percentage is as follows Ni 30%; Cr 20%; Al 6%; C 0.03%; B 0.016%; Co 2%; Ti 3%; Nb 0.1%; La 0.2%; Ce0.2%; Fe balance.

The manufacturing method of the alloy is: melting and pouring into an ingot according to the composition of the electrothermal alloy in a vacuum induction furnace, then hot forging the alloy ingot into a rod at 1200°C-900°C, and hot rolling into a plate at 1200°C-900°C, Then cold drawn at room temperature into wires of different specifications.

The above alloys have been tested to have high thermal conductivity.

The inside of the base pipe 5 is provided with an anti-corrosion layer, and the outside of the base pipe is coated with a wear-resistant layer. The thermal expansion coefficients of the anti-corrosion layer, base pipe, and wear-resistant layer increase sequentially. The reason for this setting is that during the heating process, the inner anti-corrosion layer of the finned tube is heated first and expands first, and then the second layer and the third layer are heated and expanded outwards in turn, so the three layers of expansion times from the inside to the outside Increasing in turn can ensure that the expansion rate is basically consistent, and the tightness and stability of the connection of each layer can be ensured.

As shown in FIG. 3 , the radiator further includes a control system, which controls the flow rate of water entering the radiator according to the indoor temperature.

The control system includes: a temperature sensor (not shown in Figure 3), a flow controller 14 and a central controller 13, the flow controller 14 controls the flow rate of water entering the radiator; the temperature sensor is used to measure the indoor temperature, When the indoor temperature is lower than the first temperature, the flow controllers are fully opened. When the indoor temperature reaches the first temperature, the central controller controls the flow controller to reach the first flow rate. The first flow rate is lower than the full open flow rate. When the indoor When the temperature reaches a second temperature higher than the first temperature, the central controller controls the flow rate to reach a second flow rate lower than the first flow rate controller, and when the indoor temperature reaches a third temperature higher than the second temperature, the central controller controls The flow controller reaches a third flow rate lower than the second flow rate, and when the indoor temperature reaches a fourth temperature higher than the third temperature, the central controller controls the flow controller to reach a fourth flow rate lower than the third flow rate; when the indoor temperature When the fifth temperature higher than the fourth temperature is reached, the central controller closes the flow controller to prevent water from entering the radiator.

The fifth temperature is due to a very high temperature, such as above 25 degrees, and the first temperature is a relatively low temperature, such as below 15 degrees. Through the above settings, the more heat of the radiator can be controlled according to the temperature to achieve the effect of energy saving, especially the next step is to develop billing based on heat, so it will definitely be welcomed.

Furthermore, temperature sensors 15, 16 may be provided for measuring the temperature of the water entering and exiting the radiator.

The control system can be a single-chip microcomputer, and a control panel can be arranged, and the control panel can be arranged on the upper or lower part of the radiator, or on the pipeline entering the radiator.

The anti-corrosion layer is formed by applying anti-corrosion paint, and the anti-corrosion paint is composed of the following components: 8.3% of flake zinc powder, 8% of aluminum oxide, 7.3% of boric acid, 0.7% of acrylic acid, and 0.4% of wetting and dispersing agent, The thickener is 0.15%, the defoamer is 0.23%, and the balance is water.

A method for preparing the above-mentioned water-based anticorrosion coating, the method is implemented according to the following steps,

a. According to the total mass percentage of the coating, weigh a certain amount of water, 0.4% wetting and dispersing agent and 0.23% defoaming agent respectively, then mix them together, fully stir to dissolve them to make coating mixed solution A1, and then add Add flake metal powder accounting for 8.3% of the total mass of the coating to the mixed solution A1, and stir evenly to make the mixed solution A2 of the coating;

b. Take 7.3% boric acid according to the total mass percentage of the coating to form a mixed solution, add it to 20% to 40% water and fully dissolve it to make the inorganic acid mixed solution B1, and then add it to

Add 8% oxide powder to the mixed solution B1, stir until no precipitation is formed to make the inorganic acid mixed solution B2;

c. According to the total mass percentage of the coating, weigh 0.7% of acrylic acid, add it to 5% to 15% of water, and stir well to make the reducing agent mixture C;

d. According to the total mass percentage of the paint, weigh 0.15% thickener hydroxyethyl cellulose, add it to 2.5% to 15% water, stir until it dissolves and becomes translucent and no gel appears, then stop stirring to make a thickener. thickener mixture D;

e. Add the prepared inorganic acid mixed solution B2 into the paint mixed solution A2, then add 1/5 to 1/2 of the prepared amount of the reducing agent mixed solution C, add the thickener mixed solution D while stirring, and then add the remaining Add the appropriate amount of water and continue to stir for 30-90 minutes until the coating mixture is uniform and free of agglomerated particles. Finally, add the remaining reducing agent mixture C and stir for another 10-40 minutes to obtain the finished product.

This kind of paint is applied on the surface of finned tubes by spraying, brushing and dipping, dried at 80±10°C for 10-60 minutes, cured and sintered at 280±40°C for 30-60 minutes to form a good corrosion-resistant coating.

The wetting and dispersing agent is SA-20 in the Pingpingjia series, the thickener is selected from hydroxyethyl cellulose; the defoamer is selected from tributyl phosphate.

As shown in FIG. 1 , there are no fins in the parts near the upper and lower headers in the axial direction of the base pipe 5 . This can ensure that the air in the lower part can enter the gap formed between the fins, and at the same time come out from the upper part of the air to enhance the convection effect.

As shown in FIG. 4 , the length of the portion without fins near the lower header of the base pipe 5 is longer than the length of the portion without fins near the upper fins. The main reason is that the air surface density in the lower part is high, which can ensure the entry of more air, and the air density in the upper part is small, and the air is easier to rise, so the amount of air entering and exiting the finned tube can be kept basically the same.

Preferably, the length of the lower portion without fins accounts for 5% of the length of the base tube 5 , and the length of the upper portion without fins accounts for 3% of the length of the base tube 5 .

The inner wall of the base pipe 5 can be provided with fins, such as straight fins or helical fins, and the height of the fins can gradually increase with the direction of fluid flow, and the highest fin height is the lowest 1.05-1.1 times. The main reason is that with the direction of fluid flow, the temperature of the fluid gradually decreases, so that the heat transfer effect gradually decreases. By increasing the height of the internal fins, the heat transfer in the direction of fluid flow can be enhanced, so that the heat transfer effect along the The direction of fluid flow is generally consistent.

The inner wall of the base pipe 5 is provided with protrusions for enhancing heat transfer, and the distribution of the protrusions follows a certain rule. Preferably, along the flow direction of the fluid, the distribution of the protrusions becomes denser. In this way, along with the flow direction of the fluid, the temperature of the fluid gradually decreases, so that the heat exchange effect is gradually reduced. By increasing the internal fin The density of the protrusions can enhance the heat exchange in the direction of fluid flow, so that the heat exchange effect is generally consistent along the direction of fluid flow. Another preferred manner is that the height of the protrusions gradually increases along the direction of fluid flow, wherein the highest is 1.06-1.18 times the lowest. The same as the previous heat exchange principle, the main reason is that with the direction of fluid flow, the temperature of the fluid gradually decreases, so that the heat exchange effect gradually decreases. By increasing the height of the internal protrusions, the heat exchange in the direction of fluid flow can be enhanced. Heat, so that the heat exchange effect is generally consistent along the direction of fluid flow.

Because along the flow direction of the fluid in the upper header, the flow pressure of the fluid is getting smaller and smaller, so that the distribution of the fluid in the finned tube is uneven, and the fluid flow rate in the rear finned tube decreases. Therefore, in order to ensure that the upper header The pressure of the fluid in the tube remains constant, and the present invention designs that the flow area of the fluid in the upper header 1 gradually decreases along the fluid flow direction, so that the flow rate of the fluid entering the finned tube can be kept as large as possible, especially are finned tubes located downstream of fluid flow to enhance heat transfer.

As a preferred embodiment, as shown in Figure 5, a deflector 20 is provided inside the upper header 1, and the deflector 20 is in an inclined state, extending from the upper part of the upper header 1 to the bottom of the upper header 1. The lower part, so that the fluid flow area of the upper header gradually decreases from the radiator inlet pipe 18, which can ensure that the pressure of the upper header along the fluid flow direction remains consistent, so that the flow rate of the fluid entering the finned tube can be as high as possible Keep it large to enhance heat transfer.

The deflector 20 is connected to the left and right walls of the upper header, wherein on the right wall, where the radiator inlet pipe 18 is connected to the upper header 1, the deflector 20 is located at the junction of the inlet pipe and the heat collector. upper part.

The angle formed between the deflector 20 and the bottom wall of the upper header 1 is most suitable between 15° and 35°, and the pressure distribution of the entire upper header 1 is most suitable at this time.

The shape of the deflector can be a straight plate shape or a curved plate shape.

As an alternative embodiment, the deflector can be eliminated, and the upper wall surface 21 of the upper header 1 can be directly set in an inclined shape, as shown in Figure 6, extending obliquely from the position of the inlet pipe toward the lower part of the upper header 1, Therefore, in the upper header 1 , along the fluid flow direction, the fluid flow area gradually decreases from the radiator inlet pipe 18 .

The upper part of the upper header can be straight or curved.

Although the present invention has been disclosed above with preferred embodiments, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, so the protection scope of the present invention should be based on the scope defined in the claims.

Claims (1)

1. A radiator comprising an upper header and a lower header and a finned tube connecting the upper header and the lower header, said finned tube comprising a circular base tube and a first fin and a second fin, The first fin and the second fin are arranged on the outside of the base pipe and the extension lines of the first fin and the second fin intersect the central axis of the base pipe where the center of circle of the base pipe is located, the first fin and the second fin The fins are mirror-symmetrical along the first plane passing through the central axis of the substrate tube; the finned tubes include third fins and fourth fins, and the third fins and fourth fins are respectively connected to the first fins along the second plane. A fin and a second fin are mirror-symmetrical, the second plane is perpendicular to the first plane and passes through the central axis of the base pipe; a first connecting piece is arranged between the first fin and the second fin, and the A second connecting piece is arranged between the third fin and the fourth fin, and the first connecting piece and the second connecting piece are arc-shaped metal plates; The two fins and the fourth fin form a space; the central axis where the center of the arc-shaped metal plate is located coincides with the central axis of the base pipe; A deflector is arranged inside the upper header, and the deflector extends obliquely from the position of the inlet pipe of the radiator to the lower part of the upper header, so that the flow area of the fluid in the upper header gradually decreases along the fluid flow direction; The included angle between the first fin and the second fin is A, the length of the first fin and the second fin is L, the outer radius of the base pipe is R, and the fin along the axial direction of the base pipe is The slice height H satisfies the following formula: Sin(A/2)=a×(L/R) ² +b×(L/R)+c H/(R×10)= e×Sin(A/2) ² -f×Sin(A/2)+h; Among them, the unit of A is angle, 60°<A<110°, The size of L is mm, 12mm<L<80mm, The unit of R is mm, 10mm<R<80mm, The unit of H is mm, 800mm<H<1200mm, a, b, c, e, f, h are coefficients, the range of a is 0.04-0.042, the range of b is 0.266-0.28, the range of c is 0.36-0.37, the range of e is 21-23, and the range of f is 44-45, h is 23-25; It is characterized in that the interior of the base pipe is provided with protrusions, and along the flow direction of the fluid, the distribution of the protrusions becomes denser and denser.