RU2525860C1 - Dispensing chamber - Google Patents

Abstract

FIELD: machine building.SUBSTANCE: dispensing chamber is limited from outside with body and bottom (3), and interconnects by itself side supply channels (1) and central discharge channel (7) through clearances between bottom (3) and end-face parts of inner walls (2). The body is shaped by two external walls (5) and bottom (3). System of plates (6) shaping channels (4) for passing the working medium is installed in the cross section of central discharge channel (7) parallel to inner walls (2) with a clearance with respect to each other. Side supply channels (1) are divided from central discharge channel (7) by inner walls (2) oriented along outer walls (5). Outer (5) and inner (2) walls, bottom (3) and system of plates (6) are made in the form of flat plates installed vertically. The porosity coefficient of system of plates (6) corresponds to a range of 0.3 to 0.8. Given for the dispensing chamber are the relations taking into account the interrelations of a height of the dispensing chamber, a height of entrance into it, semi-width of the body, semi-width of the outer and inner portions of the central discharge channel. Given is the relation for selecting dimensions of the dispensing chamber flowpath, taking into account the average velocities of the working medium in the channel of system of plates (4) and of system of plates (6) as a whole, a height of the dispensing chamber and a height of entrance into it, semi-width of the outer portion of central discharge channel (7), semi-width of the body, number of channels (4) in system of plates (6), a width of channel (4) of system of plates (6), a current semi-width of system of plates (6) and semi-width of a perforated part of system of plates (6).EFFECT: extending functional capabilities of a device at shaping a hydrodynamic irregularity at the exit of the dispensing chamber.1 dwg

Description

The invention relates to hydrodynamics and can be used in distributing manifold systems of devices.

A distribution chamber is known, comprising a housing, inside which a shell is mounted with a gap, a cylindrical annular insert, the upper end of which is adjacent to the lower end of the shell, and the lower end is installed with a gap with respect to the bottom, coaxial lateral lowering and central outlet channels communicating with each other by a pressure head chamber, the displacer, made in the form of a cylinder with a cover, the upper part of which is brought into the cavity of the annular insert, is installed with a gap in relation to it and is located below the upper part annular insert [RF patent №2025799 «nuclear reactor"; priority from 10/02/1990; registered 12/30/1994].

A disadvantage of the known device is that it does not provide for the possibility of obtaining a given flow (velocity) profile at the outlet of the distribution chamber by providing an appropriate ratio of its sizes.

The closest in technical essence to the claimed device is a distribution chamber, bounded externally by the housing and the bottom and connecting the two side inlet channels and the central outlet channel through the gaps between the bottom and end parts of the inner walls. The housing is formed by two outer walls and a bottom. In the cross section of the central outlet channel parallel to the inner walls with a gap with respect to each other, a system of plates with channels for the passage of the working medium is installed. The lateral inlet channels are separated from the central outlet channel by inner walls oriented along the outer walls, and the outer and inner walls, the bottom and the plate system are made in the form of vertically mounted flat plates [M. Fomichev Experimental hydrodynamics of nuclear power plants. M .: Energoatomizdat, 1989. Pp. 134-141].

A disadvantage of the known device is that the design of its flowing part allows you to change the profile of the velocity (flow) of the working medium at the outlet of the plate system in a relatively narrow range due to the fact that the flow of the working medium in the gap between the plate system and the bottom is directed from the peripheral parts to center with the distribution of the flow of the working medium through the channels of the plate system.

The objective of the invention is to eliminate this drawback, namely expanding the range of changes in the velocity profile (flow rate) of the working medium at the outlet of the distribution chamber by selecting the ratio of its sizes.

To eliminate this drawback in the distribution chamber, bounded externally by the housing and the bottom and connecting the two side supply channels and the central exhaust channel through the gaps between the bottom and the end parts of the inner walls, in which the housing is formed by two outer walls and the bottom, in a cross section of the central outlet channel parallel to the inner walls with a gap with respect to each other, a system of plates is installed, forming channels for the passage of the working medium, the side supply channels about Delena from the central exhaust channel inner walls, oriented along the outer walls and the outer and inner walls, the bottom plate and the system are designed as flat plates mounted vertically, it is proposed:

- the porosity coefficient of the plate system to provide in the range from 0.3 to 0.8;

- the ratio of the size of the distribution chamber to perform in accordance with the conditions that take into account the relationship, firstly, the height of the distribution chamber and the height of the entrance to it; secondly, the heights of the entrance to the distribution chamber, the half-width of the housing and the half-width of the outer part of the central outlet channel; thirdly, the heights of the entrance to the distribution chamber, the half-width of the housing and the half-width of the outer part of the central outlet channel; fourthly, the height of the distribution chamber, the height of the entrance to it, the half-width of the housing, the half-width of the outer and inner parts of the central outlet channel; fifthly, the height of the distribution chamber, the height of the entrance to it, the half-width of the housing and the half-width of the outer part of the central outlet channel;

- associate the dimensions of the flow part of the distribution chamber with its hydrodynamic characteristics by a ratio taking into account the average speeds of the working medium in the channel of the plate system and in the plate system as a whole, the height of the distribution chamber, the height of its entrance, the half width of the outer part of the central outlet channel, the half width of the housing, the number of channels in the plate system, the channel width of the plate system, the current half-width of the plate system and the half-width of the perforated part of the plate system.

A top view of one embodiment of a distribution chamber is shown in the drawing, in which the following designations are adopted: 1 — side supply channel; 2 - inner wall; 3 - bottom; 4 - channel plate system; 5 - outer wall; 6 - plate system; 7 - the central outlet channel.

The distribution chamber is bounded externally by the housing and the bottom 3 and connects two side supply channels 1 and the central discharge channel 7 through the gaps between the bottom 3 and the end parts of the inner walls 2.

The housing is formed by two outer walls 5 and a bottom 3.

In the cross section of the Central outlet channel 7 parallel to the inner walls 2 with a gap with respect to each other, a system of plates 6 is installed, forming channels 4 for the passage of the working medium.

The lateral inlet channels 1 are separated from the central outlet channel 7 by inner walls 2 oriented along the outer walls 5.

The outer 5 and inner 2 walls, the bottom 3 and the plate system 6 are made in the form of vertically mounted flat plates.

The porosity coefficient of the plate system 6 corresponds to a range from 0.3 to 0.8.

The aspect ratio of the distribution chamber corresponds to the conditions:

$$H-h\ge 0,\left(\mathrm{one}\right)$$

$$l_{\mathrm{four}}-l_3\prec h\prec \mathrm{four}\left(l_{\mathrm{four}}-l_3\right),\left(2\right)$$

$$h-4.7l_3+1.9l_{\mathrm{four}}\ge 0,\left(3\right)$$

$$l_2-0.21H+1.05l_{\mathrm{four}}-0.65l_3+0.14h\ge 0,\left(\mathrm{four}\right)$$

$$H-0.18h+0.86l_3-0.65l_{\mathrm{four}}\ge 0,\left(5\right)$$

where H is the height of the distribution chamber, m; h is the height of the entrance to the distribution chamber, m; l ₄ - half-width of the body, m; l ₃ - half-width of the outer part of the central outlet channel 7, m; l ₂ is the half-width of the inner part of the central outlet channel 7, m.

The dimensions of the flow part of the distribution chamber are selected taking into account the hydrodynamic characteristics of its flow part in the following ratio:

$$u-\overline{u}\left(2.1-0.63\tilde{L}\right){[\left(4.8-\mathrm{2,8}\tilde{L}\right){\left(l{l}_{\mathrm{one}}^{-\mathrm{one}}\right)}^3]}^{-\mathrm{one}}=0,\left(6\right)$$

- средняя скорость рабочей среды в системе пластин 6 в целом, м/с; $$\tilde{L}=\left(\mathrm{0,21}H+\mathrm{0,1}h-\mathrm{0,42}{l}_3+\mathrm{0,56}{l}_4\right){\left(2n_0{l}_0\right)}^{-1}$$

- относительная ширина струи рабочей среды в месте встречи с системой пластин 6; H - высота распределительной камеры, м; h - высота входа в распределительную камеру, м; l₃ - полуширина наружной части центрального отводящего канала 7, м; l₄ - полуширина корпуса, м; n_o - число каналов в системе пластин 6, м; l_o - ширина канала системы пластин 6, м; l - текущая полуширина системы пластин 6, м; l₁ - полуширина перфорированной части системы пластин 6, м.where u is the average velocity of the working medium in the channel of the plate system 6, m / s; $$\overline{u}$$

- the average speed of the working medium in the system of plates 6 as a whole, m / s; $$\tilde{L}=\left(0.21H+0.1h-0.42l_3+0.56l_{\mathrm{four}}\right){\left(2n_0{l}_0\right)}^{-\mathrm{one}}$$

- the relative width of the jet of the working medium in the place of meeting with the system of plates 6; H is the height of the distribution chamber, m; h is the height of the entrance to the distribution chamber, m; l ₃ - half-width of the outer part of the central outlet channel 7, m; l ₄ - half-width of the body, m; n _o is the number of channels in the plate system 6, m; l _o - channel width of the plate system 6, m; l is the current half-width of the plate system 6, m; l ₁ - half-width of the perforated part of the plate system 6, m

Used in the ratios (1 ÷ 6) designations of the structural elements of the distribution chamber are presented in the drawing.

Relations for the determination of hydrodynamic irregularities at the outlet of the axisymmetric distribution chamber are developed taking into account the law of conservation of mass under the assumption of the constancy of the thermophysical properties of the working medium and the jet nature of its flow.

In deriving the calculated ratios, the following assumptions were made.

Moving along the bottom 3, a flat semi-flooded stream after turning in the center of the distribution chamber is converted into a round flooded stream.

When a flat half-flooded jet moves along the bottom 3 after the stabilization section, a half-flooded flat stream along the body and a flat flooded stream in the main volume of the distribution chamber, their cross-sectional area increases, accompanied by a decrease in the speed of the working medium in it.

The angle of unilateral expansion of flooded and semi-flooded jets is 12 °.

When a jet enters the system of plates 6, one part of the flow enters the channels 4 of the system of plates 6 located at the meeting point of the jet, the other flows along the system of plates 6 with a flow rate variation along the way.

Relation (2) corresponds to the relationship between the width of the lateral inlet channel 1 and the height of the entrance to the distribution chamber, relation (3) - to the condition for the reverse rotation of the working fluid stream in the distribution chamber, relation (4) - to the condition that the internal side surface of the flat flooded jet gets onto the plate system 6, and relation (5) - to the condition for the conversion of flat semi-flooded jets into a flat flooded jet in the main volume of the distribution chamber as a result of rotation of the flow.

The flow of the working medium in the flow part of the distribution chamber is as follows.

The flows of the working medium through two lateral supply channels 1 go into the distribution chamber, change the direction of movement in it, move towards each other along the bottom 3 in the form of flat semi-submerged jets, which, as a result of merging with each other and rotation in the central part of the bottom 3, are converted into a flat flooded stream. The specified jet enters the system of plates 6. One part of it enters the channels 4 of the system of plates 6 at the place of meeting with it, and its other two parts move along the system of plates 6 with the distribution of flow along its peripheral channels 4. From channels 4 of the system of plates 6 the medium enters the central outlet channel 7.

An example of a specific implementation of the distribution chamber

The distribution chamber has the following size ratios: Hh = 0; H / (l ₄ -l ₃ ) = h (l ₄ -l ₃ ) = 4; (l ₃ -l ₂ ) / l ₂ = 0.02. The porosity coefficient of the plate system 6 (ε) is 0.52. The Reynolds number in the lateral supply channel 1 (Re) is 3.2 · 10 ⁴ . In the plate system 6 there are 14 plates and 15 channels 4. The working medium is water.

не превышает ±15%.As a result of comparing the calculation results by relation (6) with the experimental data obtained for a distribution chamber that meets the conditions (1) ÷ (5), it was found that the difference in relative velocities $$u/\overline{u}$$

does not exceed ± 15%.

The technical result consists in expanding the functionality of the device during the formation of hydrodynamic unevenness at the outlet of the distribution chamber.

Claims (1)

A distribution chamber bounded externally by the housing and the bottom and connecting the two side supply channels and the central outlet channel through the gaps between the bottom and the end parts of the inner walls, the housing being formed by two outer walls, in the cross section of the central outlet channel parallel to the inner walls with a gap with respect to a set of plates is installed to each other, forming channels for the passage of the working medium, the side supply channels are separated from the central outlet channel by an internal them walls oriented along the outer walls, and the outer and inner walls, the bottom and the plate system are made in the form of vertically mounted flat plates, characterized in that when the porosity coefficient of the plate system corresponding to the range from 0.3 to 0.8, and size ratios distribution chamber corresponding to the conditions:
$$H-h\ge 0,\left(\mathrm{one}\right)$$

$$l_{\mathrm{four}}-l_3\prec h\prec \mathrm{four}\left(l_{\mathrm{four}}-l_3\right),\left(2\right)$$

$$h-4.7l_3+1.9l_{\mathrm{four}}\ge 0,\left(3\right)$$

$$l_2-0.21H+1.05l_{\mathrm{four}}-0.65l_3+0.14h\ge 0,\left(\mathrm{four}\right)$$

$$H-0.18h+0.86l_3-0.65l_{\mathrm{four}}\ge 0,\left(5\right)$$

Where
H is the height of the distribution chamber, m;
h is the height of the entrance to the distribution chamber, m;
l ₄ - half-width of the body, m;
l ₃ - half-width of the outer part of the central outlet channel, m;
l ₂ - half-width of the inner part of the central outlet channel, m;
the dimensions of the flow part of the distribution chamber are related to its hydrodynamic characteristics by the following relation:
$$u-\overline{u}\left(2.1-0.63\tilde{L}\right){[\left(4.8-\mathrm{2,8}\tilde{L}\right){\left(l{l}_{\mathrm{one}}^{-\mathrm{one}}\right)}^3]}^{-\mathrm{one}}=0,\left(6\right)$$

Where
u is the average velocity of the working medium in the channel of the plate system, m / s;
$$\overline{u}$$

- the average speed of the working medium in the plate system as a whole, m / s;
$$\tilde{L}=\left(0.21H+0.1h-0.42l_3+0.56l_{\mathrm{four}}\right){\left(2n_0{l}_0\right)}^{-\mathrm{one}}$$

- the relative width of the jet of the working medium at the meeting point with the plate system;
H is the height of the distribution chamber, m;
h is the height of the entrance to the distribution chamber, m;
l ₃ - half-width of the outer part of the central outlet channel, m;
l ₄ - half-width of the body, m;
n _o is the number of channels in the plate system, m;
l _o - channel width of the plate system, m;
l is the current half-width of the plate system, m;
l ₁ - half-width of the perforated part of the plate system, m