JP2015132454A - Evaporation type cooling heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an evaporation type cooling heat exchanger which improves gas accumulation of a refrigerant gas, improves the heat exchange efficiency, and efficiently cools a cooled fluid.SOLUTION: An evaporator 100 includes: a heat exchange part 110 having tubes 111, 111 extending along a refrigerant traveling direction D1; a lower header pipe 120 which is connected with lower ends of the tubes 111 and flows a refrigerant liquid supplied to the tubes 111 from the upstream side to the downstream side in a refrigerant liquid inflow direction D2; and an upper header pipe 130 which is connected with upper ends of the tubes 111 and flows a refrigerant gas, which flows thereinto from the tubes 111, from the upstream side to the downstream side in a refrigerant gas discharge direction D3 that is parallel to the refrigerant liquid inflow direction D2 and the same direction as the refrigerant liquid inflow direction D2.

Description

  The present invention relates to an evaporative cooling heat exchanger.

  Conventionally, as a cooling device that cools a fluid to be cooled in a sealed room such as a server room or a clean room, the refrigerant liquid is forced by a natural circulation heat exchange device that sends the refrigerant liquid by its own weight or a liquid feed pump. A pump-type heat exchange device is known. In particular, the former cooling device can be operated with energy saving and is widely used.

  As such a cooling device, for example, an evaporative cooling heat exchanger having a heat exchange part for evaporating the refrigerant liquid, a condenser for condensing the refrigerant gas, and the refrigerant gas from the evaporative cooling heat exchanger to the condenser A gas pipe and a liquid pipe that guides a refrigerant liquid from a condenser to an evaporative cooling heat exchanger are known.

  Further, as an evaporative cooling heat exchanger as described above, as shown in FIG. 8, a heat exchange unit 201 that is disposed obliquely with respect to the vertical direction V and cools the fluid to be cooled, and along the horizontal direction H. The first header pipe 202 that extends and is connected to the lower end of the heat exchanging part 201, supplies the refrigerant liquid into the heat exchanging part 201, and extends along the horizontal direction H and is connected to the upper end of the heat exchanging part 201 to An evaporative cooling heat exchanger 200 including a second header pipe 203 into which refrigerant gas flows from the exchange unit 201 is known.

  In such an evaporative cooling heat exchanger 200, the refrigerant liquid that has flowed into the lower portion of the heat exchange unit 201 from the upstream end 202a of the first header pipe 202 is evacuated to the refrigerant gas by heat exchange with the fluid to be cooled. The refrigerant gas flows into the second header pipe 203 through the upper part of the heat exchanging portion 201 along the refrigerant traveling direction D1, and flows out from the downstream end 203a of the second header pipe 203. The refrigerant liquid and the refrigerant gas are allowed to flow in a substantially U shape in plan view.

  However, in the evaporative cooling heat exchanger 200 as described above, the refrigerant gas flowing into the upstream side of the second header pipe 203 from the heat exchange unit 201 flows from the heat exchange unit 201 to the downstream side of the second header pipe 203. Since the flow path is longer than the refrigerant gas flowing into the second header pipe 203 and the frictional resistance received from the second header pipe 203 is difficult to flow, the refrigerant gas is not sent into the second header pipe 203 but locally in the upper part of the heat exchange unit 201. In some cases, a gas reservoir G is formed, and the range occupied by the saturated refrigerant gas in the heat exchanging portion 201 is reduced by an amount corresponding to the formation of such a gas reservoir G, and the evaporative cooling heat exchanger The heat exchange efficiency of 200 may be reduced.

  Therefore, the technology to be solved in order to efficiently cool the fluid to be cooled by improving the gas accumulation of refrigerant gas in the evaporative cooling heat exchanger, improving the heat exchange efficiency of the evaporative cooling heat exchanger The present invention aims to solve this problem.

  The present invention proposes to achieve the above object, and the invention according to claim 1 is an evaporative cooling heat exchanger that evaporates the refrigerant liquid into the refrigerant gas and cools the fluid to be cooled. A heat exchange part having a plurality of tubes extending along the refrigerant traveling direction of the refrigerant gas, and connected to the lower end of the tube, extends in a horizontal direction substantially perpendicular to the refrigerant traveling direction, and is supplied into the tubes. A lower header pipe that flows the refrigerant liquid from the upstream side to the downstream side in the refrigerant liquid inflow direction, and an upper end of the tube that extends in the horizontal direction and flows the refrigerant gas flowing in from the tube into the refrigerant liquid inflow An evaporative cooling heat exchanger is provided that includes an upper header pipe that flows from the upstream side to the downstream side in the refrigerant gas discharge direction that is parallel to the direction and in the same direction as the refrigerant liquid inflow direction.

  According to this configuration, the sum of the length of the flow path of the refrigerant liquid supplied from the lower header pipe to the heat exchange section and the length of the flow path of the refrigerant gas vaporized in the heat exchange section is the refrigerant to the upper header pipe. Regardless of the gas inflow position, the frictional resistance received by the refrigerant liquid and refrigerant gas in the evaporative cooling heat exchanger is substantially equal regardless of the flow position. Compared to an evaporative cooling heat exchanger that supplies from the upstream end of the header pipe and draws the refrigerant gas from the downstream end of the upper header pipe, the refrigerant gas can easily escape through the heat exchange section and the upper header pipe. In addition, it is possible to suppress the occurrence of a refrigerant gas pool in the heat exchange unit.

  According to the first aspect of the present invention, since the accumulation of the refrigerant gas in the heat exchange part is suppressed, the heat exchange efficiency between the evaporative cooling heat exchanger and the fluid to be cooled can be improved.

The schematic diagram which shows the cooling device using the evaporative cooling heat exchanger which shows one Example of this invention. The top view which shows an evaporative cooling heat exchanger. The front view of the evaporative cooling heat exchanger shown in FIG. The left view of the evaporative cooling heat exchanger shown in FIG. The schematic diagram which shows distribution of the refrigerant gas of the evaporative cooling heat exchanger used for the cooling device of this invention, and a refrigerant | coolant liquid. The perspective view which shows the evaporative cooling heat exchanger to which the linear tube is applied. The perspective view which shows the evaporative cooling heat exchanger to which the tube folded in Z shape by the side view is applied. The schematic diagram which shows the evaporative cooling heat exchanger used for the conventional cooling device.

  The present invention achieves the purpose of improving the heat exchange efficiency of the evaporative cooling heat exchanger and efficiently cooling the fluid to be cooled by improving the gas reservoir of the refrigerant gas in the evaporative cooling heat exchanger. In order to do so, an evaporative cooling heat exchanger that evaporates the refrigerant liquid into the refrigerant gas and cools the fluid to be cooled, the heat exchange unit having a plurality of tubes extending along the refrigerant traveling direction of the refrigerant gas; A lower header pipe connected to the lower end of the tube, extending in a horizontal direction substantially perpendicular to the refrigerant traveling direction, and flowing the refrigerant liquid supplied into the tube from the upstream side to the downstream side in the refrigerant liquid inflow direction; An upper header pipe that is connected to the upper end and extends in the horizontal direction and allows the refrigerant gas flowing in from the tube to flow from the upstream side to the downstream side in the refrigerant gas discharge direction that is parallel to the refrigerant liquid inflow direction and in the same direction as the refrigerant liquid inflow direction. And with It was realized by Rukoto.

  Hereinafter, a cooling device 1 using an evaporator 100 as an evaporative cooling heat exchange according to an embodiment of the present invention will be described with reference to FIG. In the present embodiment, the cooling device 1 that cools the inside of a large number of server racks r and the server room R that accommodates these server racks r will be described, but the cooling device 1 may be applied to a dry room or a clean room. I do not care.

  The server room R accommodates a plurality of server racks r each mounting an electronic device (not shown). A fan (not shown) installed in the server rack r cools the communication device, releases warm air A1 as a fluid to be cooled to the outside of the server rack r, and takes in cool air A2 outside the server rack r into the server rack r. . The warm air A1 warmed by the heat generated by the electronic device is cooled by the cooling device 1 and returned to the server room R again, so that the temperature in the server room R is kept constant. It is designed to operate within the temperature range.

  The cooling device 1 is a natural circulation heat exchange device that cools the inside of the server room R. The cooling device 1 includes an evaporator 100 as an evaporative cooling heat exchanger provided in the server room R, a condenser 10 provided outside the server room R, and refrigerant gas from the evaporator 100 to the condenser 10. A gas pipe 20 for guiding and a liquid pipe 30 for guiding the refrigerant liquid from the condenser 10 to the evaporator 100 are provided.

  The evaporator 100 is accommodated in the casing 101 and attached to the ceiling or side wall of the server room R so as to be disposed above the rack r. The evaporator 100 vaporizes the refrigerant liquid flowing from the condenser 10 via the liquid pipe 30 into the refrigerant gas, and cools the warm air A1 to the cold air A2.

  The condenser 10 condenses the refrigerant gas sent from the evaporator 10 via the gas pipe 20 into a refrigerant liquid. Specifically, the condenser 10 circulates cooling water cooled by a cooling tower or a refrigerator (not shown), and condenses the refrigerant gas into the refrigerant liquid by releasing condensation heat to the cooling water. .

  The liquid pipe 30 may be provided with a liquid feed pump that sends the refrigerant liquid to the evaporator 100. In addition, when the condenser 10 is arrange | positioned above the evaporator 100, it is necessary to provide the liquid feed pump which forcibly sends a refrigerant liquid.

  Next, the configuration of the evaporator 100 will be described with reference to FIGS.

  The evaporator 100 is fixed to the casing 101 via a base 102 that is a rectangular frame. The casing 101 is formed with a circular suction port 101b that is formed on the bottom surface 101a and sucks warm air A1, and a lattice-shaped discharge port 101d that is formed on the side surface 101c and discharges cold air A2.

  A fan 103 that rotates around the rotation axis A and takes in warm air A1 into the evaporator 100 is attached above the suction port 101b of the casing 101. Further, in the casing 101, there is a control device 104 that controls the rotational speed of the fan 103 and changes the amount of air passing through the evaporator 100 according to the suction temperature of the warm air A1 detected by a temperature sensor (not shown). Has been placed.

  The base 102 is erected on the bottom surface 101a of the casing 101 so that the refrigerant gas in the evaporator 100 rises in the vertical direction V along the traveling direction D of the refrigerant with respect to the bottom surface 101a of the casing 101. Thus, the evaporator 100 is fixed obliquely. Thereby, the heat exchange area of the evaporator 100 can be increased and the warm air A1 in the server room R can be efficiently cooled.

  The evaporator 100 is connected to the heat exchanging unit 110 having a plurality of tubes 111 and 111 extending along the refrigerant traveling direction D1 of the refrigerant gas, and the lower end of the tube 111, and the refrigerant liquid flowing in from the liquid pipe 30 is tubed. A lower header pipe 120 to be supplied to 111, and an upper header pipe 130 that is connected to the upper end of the tube 111 and flows the refrigerant gas flowing in from the tube 111 to the gas pipe 20.

  The heat exchanging unit 110 is configured by arranging a plurality of tubes 111 and 111 extending along the refrigerant traveling direction D1 with a gap therebetween along a horizontal direction H substantially perpendicular to the refrigerant traveling direction D1. As the refrigerant liquid in the heat exchanging unit 110 rises along the refrigerant traveling direction D1, heat is exchanged with the warm air A1, and the refrigerant gas changes in the order of saturated vapor refrigerant gas and heated vapor refrigerant gas. That is, as shown in FIG. 6, the refrigerant liquid / refrigerant gas in the heat exchanging unit 110 includes a region F <b> 1 occupied by the refrigerant liquid flowing in from the lower header pipe 120, a region F <b> 2 occupied by the saturated vapor refrigerant gas, and the upper header. It is divided into a region F3 occupied by the refrigerant gas of the heating steam flowing into the pipe 130. Note that the thermal efficiency of the evaporator 100 increases in proportion to the size of the region F2 occupied by the saturated vapor refrigerant gas, so that the region F2 occupied by the saturated vapor refrigerant gas is preferably wider.

  The lower header pipe 120 extends along the horizontal direction H, and is connected to the liquid pipe 30 at the upstream end 121 on the upstream side in the refrigerant liquid inflow direction D2. The refrigerant liquid supplied into the lower header pipe 120 flows from the upstream side to the downstream side in the refrigerant liquid inflow direction D <b> 2 and flows into the tubes 111 and 111. An electronic expansion valve that controls the flow rate of the refrigerant liquid may be provided on the upstream side of the upstream end 121 of the lower header pipe 120 so as to keep the degree of superheat of the refrigerant gas constant. Thereby, the refrigerant liquid can be completely evaporated, and the warm air A1 can be efficiently cooled by the latent heat of vaporization of the refrigerant liquid.

The upper header pipe 130 extends along the horizontal direction H, and a downstream end 131 on the downstream side of the refrigerant gas discharge direction D3 parallel to the refrigerant liquid inflow direction D2 and in the same direction as the refrigerant liquid inflow direction D2 is a gas pipe. 20 is connected. The refrigerant gas that has flowed into the upper header pipe 130 flows from the upstream side to the downstream side in the refrigerant gas discharge direction D3 and flows into the gas pipe 20. Here, the upstream end 132 of the upper header pipe 130 is disposed on the same side in the horizontal direction H as the upstream end 121 of the lower header pipe 120 (on the right side in FIG. 3) in plan view. . Further, the downstream end 131 of the upper header pipe 130 is disposed on the same side (left side in FIG. 3) in the horizontal direction H in the downstream end 122 of the lower header pipe 120 in plan view.
Thereby, the sum of the length of the flow path of the refrigerant liquid supplied from the lower header pipe 120 to the heat exchange section 110 and the length of the flow path of the refrigerant gas vaporized in the heat exchange section is the refrigerant to the upper header pipe 130. Since the frictional resistance received by the refrigerant liquid and the refrigerant gas in the evaporator 100 is substantially equal regardless of the position where the refrigerant liquid and the refrigerant gas flow, the plane is flat. Compared with a conventional evaporative cooling heat exchanger in which the refrigerant liquid and the refrigerant gas flow in a substantially U shape as viewed, the refrigerant gas can easily escape through the heat exchanger 110 and the upper header pipe 130.

  In the evaporator 100 according to the above-described embodiment, the refrigerant gas easily escapes from the heat exchanging unit 110 and the upper header pipe 130, so that the occurrence of a refrigerant gas pool in the heat exchanging unit 110 is suppressed. Thus, the heat exchange efficiency of the evaporator 100 can be improved.

  Moreover, the cooling device 1 according to the present embodiment can efficiently cool the server room R using the evaporator 100 having excellent heat exchange efficiency.

  In addition, as shown in FIG. 6, the tube 111 in the present embodiment adopts a straight line extending from the bottom to the top as shown in FIG. 6. However, the shape of the tube used for the heat exchange unit is a straight line. For example, in the case of the tube 111 used in the forced circulation cooling device, as shown in FIG. 7, the tube 111 is bent up and down twice and has three Z-shaped rows in a side view. Alternatively, it may be an odd-numbered row that is bent twice or more even times.

  The present invention can be variously modified without departing from the spirit of the present invention, and the present invention naturally extends to the modified ones.

DESCRIPTION OF SYMBOLS 1 ... Cooling device 10 ... Condenser 20 ... Gas piping 21 ... Bypass piping 30 ... Liquid piping 100 ... Evaporator (evaporative cooling heat exchanger)
101 ... casing 102 ... base 103 ... fan 104 ... control device 110 ... heat exchange part 111 ... tube 120 ... lower header pipe 121 ... (lower header pipe ) Upstream end 122 ... Downstream end 130 (of lower header pipe) ... Upper header pipe 131 ... Downstream end 132 (of upper header pipe) ... (Upper header pipe) Upstream end R ... Server room r ... Server rack F1 ... Area occupied by refrigerant liquid F2 ... Area occupied by saturated steam F3 ... Area occupied by heated steam A1 ... Warm air A2 ... Cold air D1 ... Refrigerant traveling direction D2 ... Refrigerant liquid inflow direction D3 ... Refrigerant gas discharge direction H ... Horizontal direction V ... Vertical direction

Claims (1)

An evaporative cooling heat exchanger that evaporates a refrigerant liquid into a refrigerant gas and cools a fluid to be cooled.
A heat exchanging section having a plurality of tubes extending along the refrigerant traveling direction of the refrigerant gas;
A lower header pipe connected to the lower end of the tube, extending in a horizontal direction substantially perpendicular to the refrigerant traveling direction, and flowing the refrigerant liquid supplied into the tube from the upstream side to the downstream side in the refrigerant liquid inflow direction; ,
Connected to the upper end of the tube, extends in the horizontal direction, and flows the refrigerant gas flowing in from the tube in parallel with the refrigerant liquid inflow direction and in the same direction as the refrigerant liquid inflow direction from the upstream side to the downstream side An upper header pipe that flows toward
An evaporative cooling heat exchanger comprising:

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