WO2014175786A1

WO2014175786A1 - System for the liquid cooling of a multiprocessor computing complex, an assembly, and a thermal conduction module

Info

Publication number: WO2014175786A1
Application number: PCT/RU2014/000299
Authority: WO
Inventors: Виталий Викторович АНАНЬЕВ; Николай Владимирович БОДУНОВ; Алексей Михайлович МАКАРУШКИН; Ксения Сергеевна МЕЩЕРЯКОВА; Андрей Феликсович СЛЕПУХИН; Антон Валериевич СМОЛЕНСКИЙ
Original assignee: Открытое акционерное общество "Т-Платформы"
Priority date: 2013-04-25
Filing date: 2014-04-24
Publication date: 2014-10-30
Also published as: RU2522937C1

Abstract

The claimed group of inventions relates to the field of cooling devices used in digital computing and data processing devices, and can be used in the design of server platforms for high-performance computing and computer simulation. A thermal conduction module of a liquid cooling system comprises an upper and a lower part, which are connected by vacuum soldering. The surfaces of these parts are provided with rectangular recesses, formed by milling, in the shape of electronic circuit board components which are mounted in said recesses in order to provide optimal coupling. The thermal conduction module is provided with internal supply and discharge channels, arranged in parallel. Furthermore, a flexible supply hose and a flexible discharge hose are rigidly connected at on end to the thermal conduction module by means of a non-detachable fitting. The other ends of the flexible hoses are connected to an inlet fitting and an outlet fitting, which are situated by means of a quick-disconnect coupling on conduits for the supply and discharge of a heat transfer agent. The assembly additionally comprises electronic component boards, which are mounted on each side of the thermal conduction module in order to provide optimal coupling, and a thermal interface material situated between the surface of the thermal conduction module and the electronic components of a board. The claimed group of inventions makes it possible to increase the efficiency with which heat is removed from a cabinet by improving the design of a thermal conduction module and enabling regulated heat removal without changes to the structure of the cabinet.

Description

LIQUID COOLING SYSTEM

MULTI-PROCESSOR COMPUTER COMPLEX, ASSEMBLY AND HEAT REMOVING MODULE

The claimed group of inventions relates to the field of cooling devices used for digital computing and data processing devices and can be used in the design of server platforms designed for high-performance computing and computer simulation.

It is known from the prior art that a cooling device for a printed circuit board in contact with the printed circuit board is made of a metal plate, on the surface of which there are holes for attachment to the printed circuit board, and fins, heat-removing pads in contact with the heat-generating elements of the printed circuit board, which are interfaced with cylindrical surfaces with each other friend and with fins. At the same time, holes for air inlet are made in the area of least heating of the cooling device and along the perimeter of the cooling device, and holes for air outlet are made in the region of the greatest heating of the cooling device, which are located at the places where the heat sinks go to the fins, where the sectional profile of the cooling device changes stepwise (RU 2361378 C2, class N05K 7/20, publ. 10.07.2009). The disadvantage of this technical solution is the use of air as a refrigerant, which does not allow efficient cooling of the components of the printed circuit board.

From the prior art, a cabinet of electronic equipment is known, comprising a housing, plates located one above the other and forming horizontal sections in which removable blocks of electronic equipment, a heat sink system are placed. The heat sink system consists of plates connected to the rear wall of the cabinet. In this case, the plates and the back wall of the cabinet are made of heat-conducting material. On the outer side of the rear wall of the cabinet, fastening means for a heat sink plate with additional cooling means on its outer side are installed. The end contact of each plate with the rear wall of the cabinet is carried out through heat-conducting paste (RU 17107 U1, class N05K 7/20, publ. 10.03.2001).

The disadvantage of this technical solution is the lack of effective cooling, since heat is removed by radiation from the rear wall of the cabinet. And additional cooling of the implementation by means of a plate with channels for supplying air or water, which is installed on the rear wall of the cabinet.

In the prior art, a cabinet with electronic equipment comprising plates of highly heat-conducting material, a closed heat pipe for removing heat, a fan for blowing the back cavity, a protective casing, a control unit and a temperature sensor is known, the cabinet body being hermetically tight, the front panel contains an indicator of temperature conditions, heat transfer plate in contact with the system heat pipe evaporation zones, heat pipe condensation zone in thermal contact with the high-conductivity plate and the cold bridges mounted on it by cold junctions in the staggered manner with thermal bridges, the control unit is electrically connected to the indicator, fan system, temperature sensor and power supply unit (RU 2399174 C1 , CL H05K 7/20, publ. 09/10/2010).

The disadvantage of this technical solution is the very high thermal resistance for use in systems with a high level of heat generation, and this solution also does not provide quick installation and dismantling of computing and communication equipment.

A heat sink module comprising a cover and a base is known in the art. The channel is located on the outer surface of the base. There are also zigzag ribs fixed to the channel by soldering. The lid is fixed on the base by soldering to close the channel. The base is equipped with inputs and outputs that are connected to the channel. The bottom surface of the base is firmly connected to the connectors of the inputs and outputs. Zigzag fins and heat sink module are connected by soldering, the heat transfer surface is large, the coolant forms a turbulent flow in the ribs to improve heat transfer efficiency, the voltage drop is low, the connection between the ribs and the heat sink module is high, the fins and heat sink module are connected using a stainless steel connector (CN 202354023 U, H05K 7/20, published on July 25, 2012). The disadvantage of this technical solution is the lack of effective cooling.

The closest analogue to the claimed group of inventions is a heat sink module, assembly and cooling system. The heat-removing module contains a lid and a base, where the heat-emitting rib is located on the lid, the heat-emitting rib is made by extrusion of aluminum. The base is provided with a channel connected to a heat-radiating rib. The heat-emitting rib is centered in the channel and the lid is soldered to the base. A cover including a heat-emitting rib on the heat-removing module is made by extrusion of aluminum. Thus, the cost of the heat sink finned module is reduced. And the Cover and base of the heat sink module are connected with a high degree of reliability (CN 202352650 U, H01L 23/473, publ. 25.07.2012).

The disadvantage of this technical solution is that there is a difference in the heat transfer intensity between the lid with the extruded heat-emitting ribs and the base, with which the heat-emitting ribs are contacted by soldering due to the uneven thickness of the base and the lid, as well as the presence of a solder layer. When two identical heat-generating elements are installed on this heat-dissipating module from the cover and from the base side, the heat-generating elements will function in different thermal conditions.

There is a need for technical solutions that would allow for efficient uniform heat dissipation from all components of the board. The technical result of the claimed group of inventions is to increase the efficiency of heat removal from the cabinet volume by improving the design of the heat sink module and ensuring optimal thermal conditions without changing the cabinet design system.

The objective of the claimed group of inventions is the development of a water cooling system for a multiprocessor computing complex.

The use of thermal interface materials allows for the best heat transfer between the heat-generating elements (electronic components of the boards) and the heat-removing module.

The advantage of water cooling is more efficient cooling of electronic components of the boards, compactness compared to air-cooled systems, the possibility of cooling with "warm water" (temperature at the inlet of the distribution unit is 30-45 ° C), the ability to utilize the heat generated by supercomputers for heating or cooling using adsorption heat exchangers.

The task is achieved by the implementation of the heat sink module of a multiprocessor computer complex containing the upper and lower parts connected by vacuum soldering, on the surface of which rectangular recesses are made by milling in the form of electronic components of the board, which are installed in them to ensure optimal coupling with the possibility of achieving the best heat transfer, at this heat sink module equipped with internal inlet and outlet channels; flexible inlet and outlet hoses for inlet and outlet coolant; while some ends of the inlet and outlet flexible hoses are rigidly connected by means of a one-piece fitting to the heat sink module, while the other ends of the flexible hoses are connected to the inlet and outlet fittings located on the pipelines for supplying and discharging the coolant by means of a quick connector.

The material of the upper and lower parts of the heat sink module is an aluminum alloy, preferably A1 6063 or A1 6082.

The electronic components of the board are the central processing unit (CPU), the voltage regulator module (CPU VRM) of the central processing unit, the memory module (DDR3 Ch p), the voltage regulator module (DDR VRM) of the DDR3 memory module, the input / output controller-hub (PCH), the converter DC voltage (DC / DC), memory module (DDR3), solid state drive (SSD), controller (Navy), Navy controller voltage regulator module (Navy VRM), controller (FDR InfiniBand), controller (1G Ethernet).

The method of manufacturing the inlet and outlet channels is the through drilling method.

The coolant for cooling the electronic components of the boards is water.

As a quick connector use a connector type SPT08.

The task is achieved by assembling a multiprocessor computing complex, including a heat sink module of a multiprocessor computing a complex containing the upper and lower parts connected by vacuum soldering, on the surface of which rectangular recesses are made by the milling method in the form of electronic components of the board, which are installed in them to ensure optimal coupling with the possibility of achieving the best heat transfer, while the heat sink module is equipped with internal supply and exhaust channels flexible inlet and outlet hoses for inlet and outlet coolant; while some ends of the inlet and outlet flexible hoses are rigidly connected by means of a one-piece fitting to the heat sink module, and the other ends of the flexible hoses are connected to the inlet and outlet fittings located on the pipelines for supplying and discharging the coolant by means of a quick disconnect connector; as well as boards of electronic components mounted on each side of the heat sink module to ensure optimal coupling with the possibility of achieving the best heat transfer; thermal interface material located between the surface of the heat sink module and the electronic components of the board; at the same time, holes are made on the surface of the boards of electronic components for attaching to the surface of the heat sink module.

The number of boards is from 2 to 4.

The thermal conductivity of the thermal interface material is at least 6 W / mK.

The thickness of the thermal interface material is from 0.1 to 2 mm.

The problem is achieved by performing a liquid cooling system of a multiprocessor computing a complex comprising at least one pipe for supplying coolant and at least one pipe for draining the coolant, located in the lateral compartments of the front of the computing rack and separated from the rest by hermetic housings connected to the drainage system in the hydraulic distribution unit, through which the coolant is supplied; a heat sink module of a multiprocessor computer complex containing upper and lower parts connected by vacuum soldering, on the surface of which rectangular recesses are made by the shape of the electronic components of the board, which are installed in them to ensure optimal coupling with the possibility of achieving the best heat transfer, while the heat sink module is equipped with internal inlet and outlet channels; flexible inlet and outlet hoses for inlet and outlet coolant; while some ends of the inlet and outlet flexible hoses are rigidly connected by means of a one-piece fitting to the heat sink module, and the other ends of the flexible hoses are connected to the inlet and outlet fittings located on the pipelines for supplying and discharging the coolant by means of a quick disconnect connector; as well as electronic component boards mounted on each side of the heat sink module; thermal interface material located between the surface of the heat sink module and the electronic components of the board; at the same time, holes are made on the surface of the boards of electronic components for attaching to the surface of the heat sink module.

Permissible inlet water temperature range the distribution unit is 30-45 ° C, preferably 44 ° C.

The length of the flexible hoses is 10-20 cm.

The internal equivalent diameter of the pipeline is 48 mm.

The flow rate of the coolant inside each pipeline is at least 4 l / s.

The temperature difference at the inlet and at the outlet of the system is at least 5 ° C.

These advantages, as well as features of the claimed group of inventions are illustrated by the best embodiment of the device with reference to the accompanying drawings:

FIG. 1 Three-dimensional model of the heat sink module

FIG. 2 Three-dimensional model of the configuration of the arrangement of channels in the heat sink module

FIG. 3 Three-dimensional model of the assembly of the heat sink module with four boards of the computing node

FIG. 4 Layout of electronic components with the designation of heat dissipation (W) on the circuit board

FIG. 5 Temperature range of electronic components of the boards on both sides of the heat sink module

FIG. 6 Range of fluid pressure in the channel The heat sink module (1) of the multiprocessor computing complex contains the upper (2) and lower (3) parts. The connection of the upper (2) and lower (3) parts is carried out by vacuum soldering. At the same time, rectangular recesses (4) are made on the surface of the heat sink module by the milling method. The shape of the recesses follows the design of the electronic components of the boards (5) installed on it with the possibility of ensuring optimal pairing.

The heat sink module contains flexible inlet and outlet hoses (not shown in the figures). The coolant is fed through the flexible inlet hose to the channels (6) of the heat-removing module, and the coolant is diverted through the flexible outlet hose. Water is used as a heat carrier.

At the same time, one end of the flexible inlet and outlet hoses is rigidly connected by means of an integral fitting (7) to the heat sink module. And the other ends of the flexible hoses are connected to the inlet and outlet fittings located on the pipelines for supplying and discharging the coolant via a quick connector (not shown in the figures).

As a quick connector use a connector type SPT08.

Water is used as a heat carrier with a nominal heat carrier temperature of 44 ° С at the inlet; the admissible temperature range at the inlet is 30-45 ° С.

At the same time, a coolant with a temperature of 30-45 ° C, preferably 44 ° C, enters the hydraulic distribution unit, then it enters the flexible supply hose through the pipe for supplying the coolant and then into the channels (6) of the heat-removing module (1). Having passed through the channels of the cooling module, the coolant with increased temperature returns through a flexible outlet (7) hose, then through the outlet pipe to the tank (not shown in the figures).

At the same time, signals from temperature sensors are used to control the temperature on the board, which are installed on the board and near the processors.

The thermal interface material, which provides the best heat transfer between the heat-generating elements, namely, the electronic components of the boards, and the heat-removing module, is located

between the central processor and the base of the heat sink module: thickness 0.15 mm, thermal conductivity 6 W / m * K;

between the InfiniBand microcircuits and the input / output controller-hub (PCH) and the base of the heat-removing module: thickness 0.5 mm, thermal conductivity 6 W / m * K;

- between VRM voltage converters and DDR3 memory modules and the base of the heat sink module: thickness 0.5 mm, thermal conductivity 6 W / m * K;

- between the end part of the 48V / 12V DC voltage converter and the base of the heat sink module: thickness 0.5 mm, thermal conductivity 6 W / m * K;

between the other heat-generating electronic components of the circuit and the base of the heat-removing module: thickness less than 1.0 mm, thermal conductivity 6 W / m * K. The liquid cooling system is used to cool most of the equipment of the computing rack, including the computing node, control and monitoring modules, InfiniBand switches for communication and auxiliary networks, Ethernet control and service network switches.

The rated heat dissipation power (W) of each of the electronic components of the board is presented in Table 1. The highest heat dissipation power of the central processor (CPU) is 130 watts. The number of electronic components on one board is 25 pieces. And accordingly, the nominal heat dissipation power from one board is 461, 41 watts. Accordingly, the total heat dissipation power from the maximum installed boards (4 pieces) is 461.41 * 4 = 1845.64 watts.

Tab. 1 Rated heat dissipation power of the electronic components of the circuit board

Example 1

When calculating the design of the heat sink module, a design with the following characteristics was taken as a sample:

Length: 503 mm (with block of inlet / outlet fittings);

Width: 434 mm;

Thickness: 12 mm;

Material: aluminum alloy, thermal conductivity 180 W / m * K;

Maximum surface temperature: 55 ° C;

Peak pressure: <6 * 10 ⁵ Pa;

Number of internal inlet / outlet channels: 16;

The section of the inlet / outlet channels: round, channel diameter: 10 mm;

Number of inlet fittings: one;

Number of output fittings: one;

The location of the inlet / outlet fittings in the center of the heat sink module.

When calculating the design of the heat sink module, the temperature distribution was simulated in the region representing the base of the heat sink module, the space between the boards of the computing unit and the module, as well as the flow of the coolant in the module (viscous heat-conducting incompressible fluid), and the distribution of thermal fields throughout the structure under consideration. The calculations were performed without taking into account the air gap between the circuit board of the computing node and the base of the heat-removing module. Optimum results were obtained for the normal functioning of the device.

Maximum temperature for metal of the cooled board is 59.3375 ° C.

Pressure loss in the channels of the cooled plate 17233, Pa. Heated water is 5 ° C. The average speed of the coolant in the channels of the cooling module is 1.6 m / s.

Claims

Claim

1. Heat sink module of a multiprocessor computing complex containing

the upper and lower parts connected by vacuum 5 soldering, on the surface of which rectangular recesses are made by milling in the shape of the electronic components of the board, which are installed in them to ensure optimal mating with the possibility of achieving the best heat transfer, while the heat sink module is equipped with internal inlet and outlet channels ;

flexible inlet and outlet hoses for supplying and discharging coolant;

in this case, one ends of the inlet and outlet flexible hoses are rigidly connected by means of a one-piece fitting to the 15 heat-removing module, and the other ends of the flexible hoses are connected to the inlet and outlet fittings located on the pipelines for supplying and removing coolant through a quick-release connector.

2. Heat sink module according to claim 1, characterized in that 20 the material of the upper and lower parts of the heat sink module is aluminum alloy, preferably A1 6063 or A1 6082.

3. The heat sink module according to claim 1, characterized in that the electronic components of the board are a central processor, a voltage regulator module for the central processor,

25 memory modules, memory module voltage regulator module, I/O controller hub, DC-DC voltage converter, memory module, solid state drive, module voltage regulator controller, controllers.

4. Heat sink module according to claim 1, characterized in that the method of manufacturing inlet and outlet channels is through drilling.

5 5. Heat sink module according to claim 1, characterized in that water is used as a coolant.

6. Heat sink module according to claim 1, characterized in that an SPT08 type connector is used as a quick connector.

Yu

7. Assembly of a multiprocessor computing complex containing

heat sink module of a multiprocessor computing complex according to any claim. 1-6;

electronic component boards mounted on each 15th side of the heat sink module;

thermal interface material located between the surface of the heat sink module and the electronic components of the board;

In this case, holes are made on the surface of the electronic component boards 20 for connection to the surface of the heat sink module.

8. Assembly according to claim 7, characterized in that the number of boards is from 2 to 4.

9. Assembly according to claim 7, characterized in that the thermal conductivity 25 of the thermal interface material is at least 6 W/mK.

10. Assembly according to claim 7, characterized in that the thickness of the thermal interface material is from 0.1 to 2 mm.

1 1. Multiprocessor liquid cooling system computing complex, including

at least one assembly of a multiprocessor computing system according to any of claims. 7-10,

at least one pipeline for supplying coolant; 5 at least one pipeline for coolant removal;

located in the side compartments of the front part of the computer rack and separated from its other parts by sealed casings connected to the drainage system in the hydraulic distribution unit, through which coolant is supplied.

12. The system according to claim 1, characterized in that the permissible temperature range of the water at the inlet of the hydraulic distribution unit is 30-45°C, preferably 44°C.

13. The system according to claim 1, characterized in that the length of the flexible 15 hoses is 10-20 cm.

14. The system according to claim 1, characterized in that the internal equivalent diameter of the pipeline is 48 mm.

15. The system according to claim 1, characterized in that the coolant flow rate inside each pipeline is at least 4 l/s.

20 16. The system according to claim 1, characterized in that the temperature difference at the inlet and outlet of the system is at least 5°C.