JP2011257977A - Cooling system for server rack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To economically cool a plurality of servers by providing no cooling pump over the servers and to stably supply each server with a constant amount of coolant according to a change of a demand for cooling.SOLUTION: The cooling system 1 distributes a coolant C by a pump 10 from a tank 4 through a water supply header 9 to a plurality of servers 3. In each of the servers 3, the coolant C passes through a nozzle 7, flows through a coolant pipe 6, cools a heating part, and then is drained into a drain header 15. As the nozzle 7, a part which flows a constant flow rate of the coolant C by applying a constant pressure and requires no actuator is used. The coolant C raised in temperature is cooled in a heat exchanger 17 and then flows through a return current pipe 16 to return to the tank 4. A controller 14 controls the pump 10 based on a signal from a pressure gauge 11, keeps a constant water supply pressure of the water supply header 9, and controls the constant flow rate of the coolant C into the nozzle 7.

Description

  The present invention relates to a system for cooling a plurality of servers stored in a server rack.

  In recent years, in order to increase the cooling capacity, a liquid cooling type cooling system using a liquid as a refrigerant has been proposed. For example, Patent Document 1 describes a cooling system as shown in FIG. This system 51 is equipped with a cooler 53 at the top of a server rack 52, and supplies the coolant C in a tank 54 to a plurality of servers 57 via a water supply pipe 56 by a circulation pump 55.

  Each server 57 is provided with a cooling pipe 59 that cools the heat generating part 58 such as a CPU, and a cooling pump 60 that sends the coolant C through the cooling pipe 59 to the heat generating part 58. Then, the coolant C that has passed through the server 57 is returned to the cooler 53 through the drain pipe 61, passed through the heat exchanger 62, and then re-supplied by the circulation pump 55.

JP 2004-246649 A

  According to the conventional cooling system 51, since the cooling pump 60 is provided in each server 57, only the necessary server 57 can be efficiently cooled based on the temperature of the heat generating portion 58. However, the number of cooling pumps 60 equal to the number of servers 57 is required, and a large circulation pump 55 in which the capacities of the respective pumps 60 are totaled must be installed (see paragraph 0037 of Patent Document 1). There is a disadvantage that the cost is high and the power consumption is increased.

  In server racks such as data centers, the cooling demand for the entire rack fluctuates frequently, such as when the number of servers installed increases or decreases, and the supply of coolant stops at the server under maintenance. In order to adapt to fluctuations in cooling demand, it is necessary to control the rotational speeds of a large number of pumps 55 and 60 using an expensive flow meter, resulting in a problem that the system becomes complicated.

  Therefore, an object of the present invention is to reduce manufacturing costs and power consumption, economically cool a plurality of servers in a rack, adapt to fluctuations in cooling demand with simple control, and provide a certain amount of cooling to each server. An object of the present invention is to provide a cooling system capable of stably supplying liquid.

  In order to solve the above problems, a cooling system of the present invention is a system for cooling a plurality of servers stored in a server rack with a coolant, and a tank for storing the coolant, and a water supply connected to the tank The header, the pump that supplies the coolant from the tank to the feed header, the nozzle that flows a constant flow of coolant from the feed header to the heat generating part of each server by applying a constant pressure, and the feed pressure of the feed header is constant And a controller for controlling the rotational speed of the pump.

  Further, the cooling system of the present invention includes a pressure gauge that detects the feed water pressure of the feed water header, and the controller controls the rotation speed of the pump based on the output of the pressure gauge. Preferably, a heat exchanger that connects the drain outlet of each server to the drain header, pipes a reflux pipe between the drain header and the tank, and lowers the temperature of the coolant after passing the server on the reflux pipe. Provided.

  According to the cooling system of the present invention, the coolant distributed to the server from the feed water header is supplied to the heat generating part through the nozzle, so that the pump is omitted from the server, the production cost and power consumption of the system are reduced, and a plurality of Server can be cooled economically. In addition, when the cooling demand of the entire rack fluctuates, the feedwater pressure of the feedwater header can be managed constantly by controlling the rotation speed of one pump, and a fixed amount of coolant can be stably supplied to each server through the nozzles. There is also an effect.

1 is an elevation view of a server rack cooling system showing an embodiment of the present invention. It is an elevational view showing a conventional server rack cooling system.

  Hereinafter, an embodiment of the present invention will be described with reference to FIG. The cooling system 1 includes a tank 4 that stores the coolant C at the top of the server rack 2. The tank 4 may be installed on a frame (not shown) of the server rack 2 or may be installed at a dedicated location away from the rack frame so that a plurality of server racks 2 can be shared. As the coolant C, an insulating fluid can be used in addition to water.

  A plurality of servers 3 are stored in the server rack 2 at regular intervals in the vertical direction. Each server 3 is provided with a cooling pipe 6 for supplying the coolant C to a heat generating part (not shown) such as a CPU or LSI. A nozzle 7 that allows the coolant C to flow from the water supply header 9 to the heat generating part of the server 3 is attached to the inlet side end of the cooling pipe 6. For the nozzle 7, a nozzle component that does not require an actuator is used in which a constant flow rate of the coolant C flows by applying a constant pressure. The diameter of the nozzle component is set based on the temperature of the heat generating portion 5 and the required amount of coolant.

  The water supply header 9 is connected to the pump 10 on the tank 4 by a pipe 12, and the pump 10 supplies the coolant C from the tank 4 to the water supply header 9 through the pipe 12, and each server from the water supply header 9 through the nozzle 7. 3 is supplied to the cooling pipe 6. A flow meter 13 for detecting the flow rate of the coolant C is provided on the pipe 12. A pressure gauge 11 for detecting the feed water pressure of the header 9 is provided at the upper end portion of the feed water header 9.

  The pump 10 and the pressure gauge 11 are connected to the controller 14. The controller 14 controls the rotation speed of the pump 10 based on the output of the pressure gauge 11 so that the feed water pressure of the feed water header 9 is constant. As a result, a constant amount of the coolant C can always be passed through the nozzle 7 and stably supplied to the heat generating portions of the servers 3.

  In each server 3, the outlet side end of the cooling pipe 6 is connected to the drainage header 15. A reflux pipe 16 is provided between the lower end of the drainage header 15 and the tank 4, and a heat exchanger 17 that lowers the temperature of the coolant C after passing through the server 3 is installed on the reflux pipe 16.

  Next, the operation of the cooling system 1 configured as described above will be described. The cooling system 1 distributes the coolant C from the tank 4 to the plurality of servers 3 via the water supply header 9 by driving a pump 10 attached to the tank 4. In each server 3, the coolant C passes through the nozzle 7, flows through the coolant pipe 6, cools the heat generating part inside, and is discharged to the drain header 15. Then, the coolant C whose temperature has risen flows into the heat exchanger 17 from the drain header 15 and is cooled here, and then returns to the tank 4 through the reflux pipe 16.

  During operation of the cooling system 1, the controller 14 constantly monitors the feed water pressure of the feed water header 9 using the pressure gauge 11. When the feed water pressure fluctuates, the controller 14 adjusts the rotation speed of the pump 10 according to the signal level from the pressure gauge 11 and controls the feed water pressure of the feed water header 9 to be constant. In this way, even if there is an empty space where no server is present in the rack 2 or the cooling liquid supply is stopped for inspection on some servers 3, the cooling demand of the entire rack fluctuates. By simply controlling the number of revolutions of the pump 10, a constant amount of the coolant C can be always supplied from the nozzle 7 to each server 3.

  Further, in each server 3, the coolant C distributed from the water supply header 9 is supplied to the heat generating part through the nozzle 7, so that unlike the conventional system, the pump can be omitted from the cooling mechanism on the server 3. 1 production cost and power consumption can be greatly reduced. In particular, since the nozzle 7 uses a nozzle component that allows the coolant C to flow at a constant flow rate under a constant pressure, there is no need to mount an actuator on the nozzle 7, and multiple servers can be controlled by simple flow control. 3 has an advantage that a constant amount of the coolant C can be stably supplied.

  The present invention is not limited to the above-described embodiment, and the configuration of each part may be changed without departing from the spirit of the invention, such as changing the number and arrangement of the servers 3 shown in FIG. 1 or the piping configuration of the coolant C. It is also possible to carry out with appropriate changes.

DESCRIPTION OF SYMBOLS 1 Cooling system 2 Server rack 3 Server 4 Tank 6 Cooling piping 7 Nozzle 9 Water supply header 10 Pump 11 Pressure gauge 14 Controller 15 Drainage header 17 Heat exchanger

Claims (3)

A system for cooling a plurality of servers stored in a server rack with a coolant,
A tank for storing the coolant, a feed water header connected to the tank, a pump for supplying the coolant from the tank to the feed water header, and a constant flow of coolant by applying a constant pressure from the feed header to each server heat generation A cooling system comprising: a nozzle that flows through the section; and a controller that controls the number of revolutions of the pump so that the feed water pressure of the feed water header is constant.   The cooling system according to claim 1, further comprising: a pressure gauge that detects a feed water pressure of the feed water header, wherein the controller controls a rotation speed of the pump based on an output of the pressure gauge.   Claims that each server's drain outlet is connected to a drain header, a reflux pipe is connected between the drain header and the tank, and a heat exchanger is installed on the reflux pipe to lower the temperature of the coolant after passing through the server. Item 3. The cooling system according to Item 1 or 2.

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