NL2005718C2

NL2005718C2 - Cooling system for a data centre as well as such a data centre.

Info

Publication number: NL2005718C2
Application number: NL2005718A
Authority: NL
Inventors: Christiaan Reijmer
Original assignee: Isaka Ltd
Priority date: 2010-11-18
Filing date: 2010-11-18
Publication date: 2012-05-22

Description

Title: Cooling system for a data centre as well as such a data centre.

DESCRIPTION

The invention relates to a system for controlling the operational 5 temperature of electronic devices, said electronic devices each comprising at least one printed circuit board containing at least one heat generating component and at least one heat exchanging component, wherein said system comprises a cooling circuit using a coolant liquid.

The invention relates also to data centres intended for housing 10 computer systems and associated electronic devices, such as telecommunications and storage systems and the like at least comprising such a cooling system.

In many electronic systems in particular data centres where large computer network systems are installed an efficient cooling of those electronic components is a significant problem. The increased implementation of computer 15 network systems as well as the continuous growth in data transfer (especially multimedia content) via the internet has put a great burden on the power consumption and temperature control due to the heat being generated in the several electronic heat generating components such as memory modules, CPUs and other components.

20 In the past various solutions have been proposed for an active temperature control, using fans, etc., as well as a passive temperature control which features the use of heat sinks creating an enlarged heat exchanging surface. However the use of heat sinks is restricted especially where limited space exist or where large numbers of electronic devices or printed circuit boards are in close 25 proximity to one another. Also the cooling by means of air is not preferred due to the low specific heat capacity and the vulnerability of the components to dew and condensation.

Anyway, temperature control in data centres has become of increasing concern.

30 It is an object of the present invention to provide an improved cooling of an electronic device or a printed circuit board for use in data centres.

It is a further object of the invention to provide a data centre implementing a large number of electronic devices provided with a system for 2 effectively controlling the operational temperature of multiple electronic devices implemented in said data centre.

In accordance with the invention said electronic devices each comprising at least one printed circuit board containing at least one heat generating 5 component and at least one heat exchanging component, wherein said system comprises a cooling circuit using a coolant liquid therein, such that during use said coolant liquid is brought in heat exchanging contact with at least one of said heat exchanging components and wherein said printed circuit board as well at least said heat generating components are covered by means of a heat exchanging material.

10 By covering said printed circuit board as well at least said heat generating components with a heat exchanging material and subsequently bringing it in heat exchanging contact with a coolant liquid the operational temperature of said heat generating components can be effectively controlled and cooled down to proper operational levels.

15 It is noted that with a heat generating or dissipating component is understood any part of an electronic device or mounted on a printed circuit board of said electronic device wherein heat is generated during normal operational conditions. The definition of a heat generating component comprises but is not limited to for example any power source, memory modules, CPUs etc. which 20 components attribute to the heat generated in said electronic device and may cause a rise in the operational temperature of the device.

Also the cooling system according to the invention can be implemented for other types of heat generating devices used in data centres, such as hard disks or other types of storage devices.

25 In a further example of the system according to the invention said at least one heat exchanging component is at least partly covered by said heat exchanging material. This provides an additional heat exchanging capability thus adding to a further improved temperature control of the device.

In particular said printed circuit board is submerged in said coolant 30 liquid.

Furthermore the cooling circuit may comprise at least one container for accommodating at least one of said electronic devices to be cooled. In particular said at least one container has at least one inlet and at least one outlet for said 3 coolant liquid.

In order to effectively cool the electronic device or more in particular said at least one heat generating component, the at least one inlet is positioned above the at least outlet in order to establish a proper circulation flow of the coolant 5 liquid.

For a proper installation of the cooling circuit and for mounting said electronic device to be cooled inside said container in accordance with a further example of the cooling system said at least one container can be closed by means of a lid. More in particular said lid forms an integral part with said electronic device and 10 preferably said lid forms an integral part with said heat exchanging material which may cover said at least one heat generating component. In another example said lid is integrally formed with the peripheral connector block.

In a further improved example wherein an additional shielding effect can be realised, the heat exchanging material is also covering or embedding the 15 power lines and signal lines. This also provides a one-part device, which facilitates the removal and changing of the device, for example in the event of a malfunction.

Preferably said coolant liquid is water thereby obviating the use of specific coolant liquids such as oil.

Preferably said heated changing material is a resin and more in 20 particular a curable resin.

For an improved cooling effect a further example of the cooling system according to the invention comprising coolant diverting elements for diverting said coolant liquid towards said at least one heat exchanging element. More in particular said coolant diverting elements are present or accommodated in said heat 25 exchanging material, whereas also said coolant diverting elements can be mounted to the inner wall of said container.

The invention will now be described in more detail with reference to a drawing which drawing shows in:

Figure 1a an example of an electronic device, more in particular a 30 printed circuit board;

Figure 1b another example of an electronic device, more in particular a printed circuit board;

Figure 2a the electronic device of Figure 1b provided with a heat 4 exchanging material in accordance with the invention;

Figure 2b a power connector cord for use with the electronic device of Figure 1b and 2a;

Figure 2c a side view of Figure 2a; 5 Figure 3 a further example of the cooling system according to the invention;

Figures 4a and 4b side views of another example of the cooling system according to the invention;

Figures 5a and 5b side views of another detail of the cooling system 10 according to the invention;

Figure 6a and 6b side views of another detail of the cooling system according to the invention.

For a better understanding of the invention, like parts will be indicated by identical numerals in the description of the figures below.

15 In Figure 1a an example is disclosed of an electronic device 10 and more in particular of a printed circuit board 10, more in particular a computer mother board which can be used in a computer and more in particular in a data centre.

In data centres large numbers of such servers with computer mother boards are implemented and are mounted in close proximity to each other in suitable 20 computer racks.

The computer mother board 10 comprises a printed circuit board 11 on which multiple electrical components and conductive leads are mounted including heat generating components 12 and 120. The heat generating components 12 are usually the CPU, memory modules and/or a power source whereas reference 25 numeral 120 denotes multiple memory modules mounted adjacent to each other.

Furthermore the computer mother board 10 is provided with a connector socket or block 13 which can be used for connecting all kinds of peripherals such as a monitor, keyboard and mouse pointing device as communication lines such as a LAN ethernet connection. Socket 14 can be used as a 30 power and/or signal socket to which a power cord or power/signal cable as depicted in Figure 2b can be connected.

This example is shown in Figure 1b wherein connector 140 is mounted in the connector socket 14 on the printed circuit board 11. The flat 5 connection cable 141 is guided across the printed circuit board towards connector 142, which accommodated or connected to the peripheral connector block 13 and/or the circumferential edge of the printed circuit board 11 using suitable connecting means (not shown).

5 Furthermore reference numerals 18 denote in Figure 1b several heat exchanging components, for example a heat sink mounted on the several heat generating components 12. Preferably said heat exchanging components are made from a metal (preferably aluminium or other metal with a high thermal conductivity) shaped as a meta casing which are placed on and over the heat exchanging 10 components 12.

The example in Figure 2a (and 2c) shows the electronic device or computer mother board 10 of Figure 1b which is now covered by a heat exchanging material 15. The heat exchanging material 15 is preferably a curable resin and/or a material having dielectric properties thereby not adversely affecting the normal 15 operational conditions of the electronic device. It is preferred that the printed circuit board together with at least the heat generating components 12, 120 are covered by the heat exchanging material 15 in particular for electric shielding purposes.

The use of a heat exchanging material 15 covering at least the heat generating components 12, 120 and said printed circuit board 11 and subsequently 20 bringing said printed circuit board 11 (and the heat generating components 12, 120) in heat exchanging contact with a coolant liquid allows for a proper temperature control of the electronic device 10 (or the printed circuit board 11).

Although in Figure 2a the complete printed circuit board 11 is covered with a heat exchanging material 15 it is noted that the heat exchanging 25 components 18 (the heat sinks) mounted on the heat generating components 12 are not necessarily completely covered. In this example the heat sinks 18 are in direct contact with the coolant liquid, thus allowing for an optimal and full heat exchanging contact and thus an optimal temperature control.

For example the memory modules 120 can be covered solely with 30 the heat exchanging material 15 (denoted in Figure 2a with reference numeral 17) whereas the uncovered heat sink(s) 18 are brought in a direct heat exchanging contact with a coolant liquid of the cooling system. This example is shown in Figure 2c wherein the memory modules 120 are covered with the heat exchanging material 6 15 (17) whereas the other heat exchanging components 18 covering the heat generating components 12 (the CPU etc.) remain uncovered or partly covered by said heat exchanging material (resin) 15.

To avoid hazardous situations it is to be noted that at least the 5 circumference of the heat exchanging components contacting the printed circuit board is properly covered by the heat exchanging material in order to avoid any coolant liquid from entering between the printed circuit board and the heat exchanging component causing a short circuit.

For a proper cooling of the electronic device 10 in accordance with 10 the invention the cooling system comprises a container 20 having upright walls 20b and a base 20a in which the electronic device 10 can be mounted.

The container 20 is provided with at least one inlet 20a and at least one outlet 20b to which supply lines (not depicted) of the cooling circuit are to be connected. Through the supply line a coolant liquid is circulated via the inlet port 22a 15 into the container 20. The coolant liquid can leave the container 20 via the outlet port 22b.

As shown in Figures 2a and 2c the electronic device 10 is covered with a heat exchanging material, wherein said heat exchanging material has a flange 16 modeled around the peripheral connector block 13. Said flange 16 forms a lid for 20 the container 20 as the flange 16 can be brought in abutment with an flange edge 21 of the upright walls 20b.

Furthermore the flange 16 is provided with a sealing ring 160 thus creating a proper sealing once the electronic device 10 is mounted inside the container 20 and the flange 16 is brought in abutment with the circumferential flange 25 edge 21 of the upright walls 20b. See Figure 4b.

In a further example as shown in Figure 2a also the power and communication lines are imbedded in said heat exchanging material before being fed out of the container 20 towards suitable power source and communication equipment thus avoiding . In this example the power leads as depicted in Figure 2b has a 30 connector 140 which is mounted in the connector socket 14 on the printed circuit board 11. See also Figure 1b. The flat connection cable 141 is thus imbedded in the heat exchanging material 15 and the connector 142 is accommodated outside the container 20. In fact and as clearly depicted in Figure 1b and 2a the connector 142 is 7 mounted or connected to the peripheral connector block 13 and/or the circumferential edge of the printed circuit board 11 using suitable connecting means (not shown). Said connection means can have a click or snap functionality co-operating with the peripheral connector block 13 and/or the circumferential edge of the printed circuit 5 board 11. The connector 142 and the peripheral connector block 13 are then embedded in the heat exchanging material 15 and formed integrally with the flange 16.

As clearly disclosed in Figure 3 the container 20 is mounted in a vertical orientation whereas in the example of Figure 4a the container 20 is 10 accommodated in a horizontal orientation. With this latter orientation it is possible to stack multiple containers in a side by side relationship in an appropriate mounting rack, such that an outlet 22b is connected with an inlet of an adjacent container and so forth for circulating the coolant liquid through the interconnected containers for cooling the electronic devices contained in it. In another fluid connection scheme all 15 inlets 22a of multiple cooling containers are connected to a main supply inlet line (not shown), whereas all outlets 22b are connected to a main discharge outlet line.

Preferably the coolant liquid is common water which allows for a cost effective solution for cooling multiple electronic devices, in particular computer mother boards in for example a data centre. The use of water as a coolant liquid 20 obviates the use of more expensive coolant liquids such as oil whereas water has furthermore a high heat exchanging capacity. Preferably the heat exchanging material can be made from a curable resin such as epoxy, or being made from polyurethane or polyethylene. These materials can be processed for example by means of injection moulding (e.g. low melt injection moulding).

25 Herewith any hazardous situation such as a electric short circuit is avoided as the power cable 141 is embedded in the heat exchanging material 15 when submerged in the coolant liquid in the container 20.

When the cooling system according to the invention is implemented for a large number of electronic devices housed in a data centre, such data centre 30 can be effectively cooled to normal operational temperatures.

In Figure 5a and 5b an example of a heat sink 12 is disclosed, which is completed covered by the heat exchanging material 15 (Figure 5b).

In yet another example, which is disclosed in Figures 6a-6b, an 8 improved cooling effect is realised by implementing cooling diverting elements 200 in the cooling system. Said coolant diverting elements 200 are present or accommodated in said heat exchanging material 15 on said printed circuit board 11 and/or are mounted to the inner wall 20' of said container 20. These diverting 5 elements 200 can be constructed as upright wall segments or flanges for diverting said coolant liquid towards said at least one heat exchanging element 17; 18.

The coolant liquid is entering the container 20 via the inlet 22a and will exit the container via outlet 22b. In order to assure that the coolant liquid is brought properly in heat exchanging contact with the heat exchanging components 10 18 (or even the heat generating components 12-120) the coolant liquid is diverted by said diverting elements 200 towards said components.

The diverting elements 200 are located at suitable positions in the flow of the coolant liquid flowing through the container 20. Herewith it is avoided that the majority of the coolant liquid will flow directly towards the outlet 22b upon entering 15 the container 20 via the inlet 22a.

The diverting elements 200 can be located against the inner wall 20' of the container 20 and/or at specific locations on or embedded in the heat exchanging material 15. The diverting elements 200 can be constructed as flanges or notches or even as grooves present in the heat exchanging material 15 thus urging 20 the coolant liquid flowing through the container 20 towards the heat exchanging elements (heat sinks).

Preferably the coolant liquid (water) is circulated through multiple containers 20 which are interconnected in a coolant circuit. The coolant liquid is cooled down in turn using an air cooled heat exchanger, for example.

25 In order to compensate for any pressure differences which may occur in each container due to temperature changes in the coolant liquid the container 20 can be provided with a relief pressure valve for equalizing said pressure differences.

30

Claims

1. System for controlling the operating temperature of electronic devices, which electronic devices each comprise at least one printing circuit, comprising at least one heat-generating part and at least one heat-exchanging part, the system comprising a cooling circuit that uses a cooling liquid, such that during operation the coolant is brought into heat-exchanging contact with at least one of the heat-exchanging parts and wherein the printing circuit as well as at least the heat-generating parts are covered with the aid of a heat-exchanging material.

The system of claim 1, wherein the at least one heat exchange member is at least partially covered by the heat exchange material.

The system of claim 1 or 2, wherein the print circuit is immersed in the cooling fluid.

A system according to any one of the preceding claims, wherein the cooling circuit comprises at least one holder for receiving the printing circuit.

5. System as claimed in claim 4, wherein the at least one holder has at least one inlet and at least one outlet for the cooling liquid.

The system of claim 5, wherein the at least one input is placed above the at least one output.

The system of claim 5, wherein the at least one input is placed at approximately the same level as the at least one output.

8. System as claimed in any of the claims 4-7, wherein the at least one holder can be closed by means of a lid.

The system of claim 8, wherein the cover forms an integrated part with the printing circuit.

10. System as claimed in claim 8, wherein the cover forms an integrated part with the heat-exchanging material.

The system of any one of claims 8-10, wherein the lid is integrated with the peripheral connector block.

12. A system according to any one of the preceding claims, wherein all power lines and signal lines are embedded in the heat-exchanging 2005 718 t material.

System according to one or more of the preceding claims, wherein the cooling liquid is water.

14. System as claimed in one or more of the foregoing claims, wherein the heat-exchanging material is a resin.

System according to one or more of the preceding claims, further comprising cooling liquid diversion elements for diverting the cooling liquid in the direction of at least one heat-exchanging element.

16. A system according to claim 15, wherein the coolant diversion elements are present or included in the heat-exchanging material.

The system of claim 15, wherein the coolant diversion elements are disposed on the inner wall of the container.

A system according to claim 16 or 17, wherein the cooling liquid diversion elements are formed as upright wall parts.

A data center intended for housing computer systems and associated electronic equipment, such as telecommunication and storage systems and the like, at least comprising a cooling system according to one or more of the preceding claims.

20 2005718