WO2019006437A1 - Improved appliance immersion cooling system - Google Patents

Abstract

An appliance immersion tank system comprising: a tank adapted to immerse in a dielectric fluid a plurality of electrical appliances, each in a respective appliance slot distributed vertically along, and extending transverse to, a long wall of the tank; a plenum, positioned adjacent the bottom of the tank, adapted to dispense the dielectric fluid substantially uniformly upwardly through each appliance slot; and a weir adapted to facilitate substantially uniform recovery of the dielectric fluid flowing through each appliance slot. In one embodiment, a reservoir is coupled to an inside surface of the long wall of the tank so as to extend horizontally across all appliance slots, wherein the weir comprises a top longitudinal edge of the reservoir.

Description

IMPROVED APPLIANCE IMMERSION COOLING SYSTEM

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is related to the US Provisional Application Serial Number 62/527,939, filed 30 June 2017 (^'Parent Provisional"), and hereby claims benefit of the filing date thereof pursuant to 37 CFR § 1.78(a)(4).

[0002] The subject matter of this application is related to US Patent Application Serial Number 14/355,533, filed 30 April 2014 ^Related Application"); which was related both to US Provisional Application Serial Number 61/737,200, filed 14 December 2012 ("First Related Provisional"); and to US Provisional Patent Application Serial Number 61/832,211, filed 7 June 2013 ("Second Related Provisional").

[0003] The subject matter of the Parent Provisional, the Related Application and the First and Second Related Applications, each in its entirety, is expressly incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention.

[0004] The present invention relates generally to electrical appliance cooling systems, and, in particular, to an improved appliance immersion cooling system and method of operation.

2. Description of the Related Art.

[0005] In general, in the descriptions that follow, we will italicize the first occurrence of each special term of art which should be familiar to those skilled in the art of immersion cooling systems. In addition, when we first introduce a term that we believe to be new or that we will use in a context that we believe to be new, we will bold the term and provide the definition that we intend to apply to that term.

[0006] In the Related Application, several prior art immersion cooling systems are summarized. Additional examples of prior art immersion cooling systems are cited in US Patent Application Publication 2011/0132579, "Liquid Submerged, Horizontal Computer Appliance Rack and Systems and Method of Cooling such a Appliance Rack", Best, et al ("Best") The subject matter of all of these prior art references, each in its entirety, is expressly incorporated herein by reference.

[0007] As a result of experience gained implementing and operating immersion cooling systems constructed in accordance with the embodiments disclosed in the Related Application, I have identified several aspects of those embodiments that could be improved:

Problem 1. In the original design, the reservoir was a separate component, mechanically attached to the back of the tank. In order to ensure that all coolant flows into the reservoir, the reservoir was placed below the weir. Consequently, the edges of the reservoir are below the liquid level. Thus, if the total volume of liquid in the tank-side fluidic components increased due to heat expansion or addition displacement, it is possible for liquid to overflow out of the reservoir. In addition to the problems/expenses related with the loss and clean-up of this fluid, suitable dielectric liquids tend to be extremely slick, and might result in serious, perhaps fatal, accidents.

Problem 2. Since the in-tank fluid supply pipes are independent components, separate from the tank, a significant amount of space is lost inside of the tank. I estimate that roughly 7% of space is dedicated on each end of the tank for these circulation components. This not only increases the footprint of the tank with respect to useable server space, but also the cost of the dielectric fluid required to fill the non-productive space.

Problem 3. Assembly of all of the several components needed to be done on location.

Further, assembly of each system typically required a team of two people per tank, and could take several days to finish. Thus, for a large installation, either a very large trained team had to be provided or assembly would take a prolonged period of time.

Problem 4. As designed, there is no way to pressure test the fluidic components before they are filled with liquid. Thus, the only way to determine if there is a leak is to fill the system with liquid and run it. If a leak is found, one or more of the components had to be drained, disassembled, repaired and reassembled. As there is no way to test for leaks in the repaired system, there is no way to guarantee that the leak was fixed or that new ones have been introduced.

Problem 5. The system controller facility is detached from the tank and cooling module. This configuration requires that the controller facility be wired directly to a line-power junction box, and from there to the individual electrical components. Wiring the system thus requires significant effort.

Problem 6. In the event that a major fluidic component, such as a heat exchanger or a pump, needed to be replaced, there is no way to perform maintenance without taking down the whole system. Indeed, even though the system is designed to be redundant, there is no way to operate the system using one set of redundant components while service is being performed on the other set. In a mission- critical installation, not being able to perform maintenance while remaining operational is not a viable option.

Problem 7. Even if it is possible to turn off the system to perform maintenance, this work has to be performed on the data center floor. For an industry that likes to keep its environments clean, having to work on water and oil pipes right next to the computer equipment is problematic.

Problem 8: the conduits conveying hot water to the remote water cooling facility and cold water back to the tank modules are sometimes routed, at least in part, across the floor of the operational site. As a result, movement of workers around the tank modules is obstructed and may result in accidents. Further, these obstructions render maintenance of the several components of the tank modules more difficult.

Problem 9: sometimes, when the system 12 is in operation, thermal expansion of the dielectric fluid will result in an overflow condition, i.e., there is, at least temporarily, simply too much fluid for the system 12 to accommodate without spillage.

[0008] I submit that what is needed is an improved appliance tank immersion system and method of operation that resolves the above problems with the best prior art immersion cooling system known to me. In particular, I submit that such a system should provide performance generally comparable to the best prior art techniques but more efficiently and effectively than known implementations of such prior art techniques.

BRIEF SUMMARY OF THE INVENTION

[0009] In accordance with one embodiment of my invention, I provide an appliance immersion cooling system comprising: a tank adapted to immerse in a dielectric fluid a plurality of electrical appliances, each in a respective appliance slot distributed vertically along, and extending transverse to, a long wall of the tank, the tank comprising: a weir adapted to facilitate substantially uniform recovery of the dielectric fluid flowing through each appliance slot; a primary circulation facility adapted to circulate the dielectric fluid through the tank, comprising: a plenum, positioned adjacent the bottom of the tank, adapted to dispense the dielectric fluid substantially uniformly upwardly through each appliance slot; a secondary fluid circulation facility adapted to extract heat from the dielectric fluid circulating in the primary circulation facility, and to dissipate to the environment the heat so extracted; and a control facility adapted to coordinate the operation of the primary and secondary fluid circulation facilities as a function of the temperature of the dielectric fluid in the tank; the improvement comprising: a reservoir coupled to an inside surface of the long wall of the tank so as to extend horizontally across all appliance slots, wherein the weir comprises a top longitudinal edge of the reservoir.

[0010] In accordance with another embodiment of my invention, I provide a tank module adapted for use in an appliance immersion cooling system, the tank module comprising: a tank adapted to immerse in a dielectric fluid a plurality of electrical appliances, each in a respective appliance slot distributed vertically along, and extending transverse to, a long wall of the tank, the tank comprising: a weir adapted to facilitate substantially uniform recovery of the dielectric fluid flowing through each appliance slot; a primary circulation facility adapted to circulate the dielectric fluid through the tank, comprising: a plenum, positioned adjacent the bottom of the tank, adapted to dispense the dielectric fluid substantially uniformly upwardly through each appliance slot; and a control facility adapted to control the operation of the primary fluid circulation facility as a function of the temperature of the dielectric fluid in the tank; the improvement comprising: a reservoir coupled to an inside surface of the long wall of the tank so as to extend horizontally across all appliance slots, wherein the weir comprises a top longitudinal edge of the reservoir.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0011] Our invention may be more fully understood by a description of certain preferred embodiments in conjunction with the attached drawings in which:

[0012] Fig. 1 illustrates, in partial cut-away form, a front perspective of an appliance immersion cooling system constructed in accordance with the Related Application;

[0013] Fig. 2 illustrates a rear perspective of the tank module shown in Fig. 1;

[0014] Fig. 3 illustrates a rear perspective of my improved appliance immersion cooling system constructed in accordance with the present invention;

[0015] Fig. 4 illustrates a top plan view of my improved tank module shown in Fig. 3;

[0016] Fig. 5 illustrates a cross-section of my improved tank module shown in Fig. 4, taken along the line A-A;

[0017] Fig. 6 illustrates a cross-section of my improved tank module shown in Fig. 4, taken along the line B-B;

[0018] Fig. 7 illustrates a cross-section of my improved tank module shown in Fig. 5, taken along the line C-C;

[0019] Fig. 8 illustrates my improved fluid circulation facility;

[0020] Fig. 9 illustrates a rear view of the tank shown in Fig. 3; and

[0021] Fig. 10, comprising Fig. 10A, Fig. 10B, Fig. IOC, Fig. 10D, Fig. lOE and Fig. 10F, illustrates my central distribution manifold.

[0022] In the drawings, similar elements will be similarly numbered whenever possible. However, this practice is simply for convenience of reference and to avoid unnecessary proliferation of numbers, and is not intended to imply or suggest that my invention requires identity in either function or structure in the several embodiments. DETAILED DESCRIPTION OF THE INVENTION

[0023] Shown in Fig. 1 (front perspective view) and Fig. 2 (rear perspective view) is an appliance immersion cooling system 10 constructed in accordance with the Related Application. Full details regarding the construction and operation of system 10 can be found in the Related Application, which is incorporated by reference herein. As noted above, this prior art system exhibits several problems that are solved in accordance with my invention as set forth hereinafter.

[0024] In the rear perspective view of Fig. 3, I have illustrated my improved appliance immersion cooling system 12 comprising: a tank 14; a central distribution manifold ("CDM") 16; and a pair of fluid circulation facilities ("FCF") 18A and 18B. For clarity, in Fig. 4, 1 have illustrated a top plan view of my system 12.

[0025] Shown in Fig. 5 is a cross-section of Fig. 4 taken along the line A-A. As can be seen, I solve Problem 1, above, by relocating the reservoir 20 to the inside of the tank module 14. In particular, I have adapted the reservoir 20 to be coupled to an inside surface of the long wall of the tank 14 so as to extend horizontally across all appliance slots (see the Related Application), wherein the weir 22 comprises a top longitudinal edge of the reservoir 20. By way of example, in the illustrated embodiment, reservoir 20 is configured to have a length substantially the same as the inside length of the tank 14, a width of only 1-2 inches, and a depth on the order of one-third to one-half the depth of the cooling fluid when the system is in operation. Toward the bottom, center of the reservoir 20, an output conduit 24 is provided to facilitate extraction of heated fluid. In addition to solving Problem 1, this configuration significantly reduces the total footprint of the tank/reservoir assembly, while reducing the time and effort to assemble the system 12 in the field.

[0026] As can also be seen in Fig. 5, 1 solve Problem 2, above, by providing a single fluid supply line 26 coupled to the inside back wall of the tank 14. In particular, I have adapted the vertical portion 26a of supply line 26 so as to fit within the shadow cast vertically downwardly by the reservoir 20, and further adapted the horizontal portion 26b to fit within the shadow cast horizontally by the plenum 28 (see, Fig. 6). Toward the top end of the vertical portion 26a, an input conduit 30 is provided to facilitate injection of cooled fluid. As can be best seen in Fig. 7, 1 have configured the plenum 28 to receive the dielectric fluid via the center thereof, thereby to reduce the total run and friction of the fluid supply line 26. In one or more of the several alternate embodiments illustrated in my Parent Provisional, the fluid supply line 26 may be configured to supply incoming cooled fluid to the opposite ends of plenum 28 via structurally integrated conduit portions. By way of these improvements, I have eliminated all impact on effective server space by these components.

[0027] To solve Problems 3 and 4, above, I have greatly improved the modularity of several of the system components. In particular, as shown in Fig. 8, my new FCF 18 comprises all of the passive and active components required to operate the system 12 (for details, see, e.g., the Related Applications). In this configuration, each of the FCFs 18 can be fully assembled and pressure tested prior to transfer to the operational site. To solve Problem 5, above, I have integrated into each FCF 18 a respective electronic control facility 32 (for details, see, e.g., the Related Application). Then, by configuring the frame 34 of each FCF 18 with wheels 36, 1 solve Problems 6 and 7, above, because a defective FCF 18, after being disconnected from the tank 14, can now be moved to a more suitable location for maintenance. This, of course, further aggravates Problem 8, above.

[0028] However, the disconnection problem, per se, still remains to be solved. To resolve the problem, I have relocated the output conduit 24 and the input conduit 30 to the lower center of the rear wall of the tank 14, as shown in Fig. 9 (see, also, Fig. 6), to facilitate quick and easy connection to my new CDM 16. As illustrated in Fig. 10, 1 have configured my CDM 16 so as to have: a front face configured to couple directly to the output conduit 24 and the input conduit 30 (see, e.g., Fig. 10E); a rear face configured to provide easy access to the several components housed within the module 16; a left face configured to couple directly to the first FCF 18A (see, e.g., Fig. 10A and Fig. 10F); and a right face configured to couple directly to the second FCF 18B (see, e.g., Fig. 10B and Fig. 10D). As can clearly be seen by comparing the location of the fluid couplers in Fig. 10D and Fig. 10F, I have configured my CDM 16 so as to be fully symmetric when viewed from the perspective of the FCFs 18. Accordingly, the operational site requires only a single type of FCF 18, thus reducing the number of different system components that must be purchased and maintained in stock. [0029] To resolve Problem 8, 1 have configured my CDM 16, as shown in Fig. 3, such that the hot water outlet 38 and cold water inlet 40 are both oriented vertically so as to connect to respective conduits (not shown) suspended from the ceiling of the operational site. As can be seen in the illustrated embodiment, my CDM 16 is configured such that these conduits may be routed directly downward through the floor if the operational site supports such an arrangement.

[0030] To resolve Problem 9, 1 provide a small overflow tank 42 (see, Fig. 10), a high fluid level sensor 44 (see, Fig. 6) suspended in the tank 14 a short distance above the level of the weir 22, and a low fluid level sensor 46 suspended in the tank 14 a short distance below the level of the weir 22. In the event the fluid level in the reservoir 20 approaches the level of the weir 22, the high sensor 44 will go active and the system 12 will divert sufficient fluid into the overflow tank 42 to deactivate the sensor 44. When the level of the fluid has fallen below the level of the weir 22, the low sensor 46 will go active and the system 12 will return sufficient fluid from the overflow tank 42 to deactivate the sensor 46.

[0031] Preferably, all of the several fluid connectors employed in my system 12 are of the "dry disconnect" type, e.g., the "FIDC" dry-release couplings from The NovaFlex Group (www.novaflex.com) or the Dry-Break® couplings from Gardner Denver (www.todo.se).

[0032] Although I have described my invention in the context of particular embodiments, one of ordinary skill in this art will readily realize that many modifications may be made in such embodiments to adapt either to specific implementations. By way of example, it will take but little effort to adapt my invention for use with electronic appliances other than contemporary servers; and to adjust the dimensions of the appliance accommodation slots accordingly. Similarly, practitioners in the art will readily recognize that other, known secondary circulation facilities may be employed effectively, including forced air, vapor compression systems, earth-water sink loops, waste heat recovery and recycling systems, and the like (see, e.g., the several alternatives discussed in Best). Further, the several elements described above may be implemented using any of the various known manufacturing methodologies, and, in general, be adapted so as to be operable under either hardware or software control or some combination thereof, as is known in this art. [0033] Thus it is apparent that I have provided an improved system and method of operation for immersion cooling of appliances and the like. In particular, I submit that such a method and apparatus provides performance generally comparable to the best prior art techniques but more efficiently and effectively than known implementations of such prior art techniques.

Claims

CLAIMS What I claim is:

1. In an appliance immersion cooling system comprising: a tank adapted to immerse in a dielectric fluid a plurality of electrical appliances, each in a respective appliance slot distributed vertically along, and extending transverse to, a long wall of the tank, the tank comprising: a weir adapted to facilitate substantially uniform recovery of the dielectric fluid flowing through each appliance slot; a primary circulation facility adapted to circulate the dielectric fluid through the tank, comprising: a plenum, positioned adjacent the bottom of the tank, adapted to dispense the dielectric fluid substantially uniformly upwardly through each appliance slot; a secondary fluid circulation facility adapted to extract heat from the dielectric fluid circulating in the primary circulation facility, and to dissipate to the environment the heat so extracted; and a control facility adapted to coordinate the operation of the primary and secondary fluid circulation facilities as a function of the temperature of the dielectric fluid in the tank; the improvement comprising: a reservoir coupled to an inside surface of the long wall of the tank so as to extend horizontally across all appliance slots, wherein the weir comprises a top longitudinal edge of the reservoir.

2. The system of claim 1 wherein the plenum is adapted to receive the dielectric fluid via the center thereof.

3. A tank module adapted for use in an appliance immersion cooling system, the tank module comprising: a tank adapted to immerse in a dielectric fluid a plurality of electrical appliances, each in a respective appliance slot distributed vertically along, and extending transverse to, a long wall of the tank, the tank comprising: a weir adapted to facilitate substantially uniform recovery of the dielectric fluid flowing through each appliance slot; a primary circulation facility adapted to circulate the dielectric fluid through the tank, comprising: a plenum, positioned adjacent the bottom of the tank, adapted to dispense the dielectric fluid substantially uniformly upwardly through each appliance slot; and a control facility adapted to control the operation of the primary fluid circulation facility as a function of the temperature of the dielectric fluid in the tank; the improvement comprising: a reservoir coupled to an inside surface of the long wall of the tank so as to extend horizontally across all appliance slots, wherein the weir comprises a top longitudinal edge of the reservoir.

4. The module of claim 3 wherein the plenum is adapted to receive the dielectric fluid via the center thereof.