Abstract:
A system, method and computer program product system for evacuating coolant from a liquid-cooled device. The system includes a coolant supply path adapted to be coupled between a coolant supply pump and the liquid-cooled device; a coolant return path adapted to be coupled between a coolant supply reservoir and the liquid-cooled device; and a coolant removal path coupled between the coolant supply path and the coolant return path. The coolant removal path is configured to evacuate coolant from the liquid-cooled device using a venturi effect from the coolant supply path to evacuate the coolant through the coolant return path into the reservoir.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention generally relates to liquid-cooled devices. More particularly, the present invention relates to a method, system and computer program product for removal of liquid coolant from liquid-cooled devices, such as electronic devices, etc., using a venturi effect to drain/siphon coolant out of the devices prior to servicing of the devices and/or prior to removal of the devices from other equipment. 
     2. Discussion of the Background 
     Over the years, systems have been developed for accommodating liquid-cooled devices, such as electronic devices, etc., implemented to use a coolant, such as a mixture of water and glycol, for heat removal during operation. These systems typically require periodic, such as yearly, etc., maintenance, wherein the device is removed, necessitating removal of coolant from the device or wherein used coolant is removed from the system and replaced with fresh coolant. This task typically is accomplished by disconnecting the electronic device from the cooling system and using a container to capture the coolant as the coolant discharges from the electronic device and the system. 
     However, as presently recognized, such conventional systems allow for contamination of the coolant, which is often recycled, allow for loss of coolant during the evacuation process, due to spillage, are inefficient, due to the required disconnection of the electronic devices from the system and require strict adherence to handling concerns, due to the environmental impact of glycol-based coolant products. 
     SUMMARY OF THE INVENTION 
     Accordingly, an object of this invention is to provide a novel method, system and computer program product for removal of liquid coolant from devices, such as electronic devices, etc., in a more efficient, safe, coolant conservative and environmentally friendly manner, as compared to conventional methods and systems. 
     The above and other objects are achieved according to the present invention by providing a novel system, method and computer program product for evacuating coolant from a liquid-cooled device. The system includes a coolant supply path adapted to be coupled between a coolant supply pump and the liquid-cooled device; a coolant return path adapted to be coupled between a coolant supply reservoir and the liquid-cooled device; and a coolant removal path coupled between the coolant supply path and the coolant return path. The coolant removal path is configured to evacuate coolant from the liquid-cooled device using a venturi effect from the coolant supply path to evacuate the coolant through the coolant return path into the reservoir. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A more complete appreciation of the invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein: 
     FIG. 1 is a block diagram of a liquid-cooled device system, according to the present invention; 
     FIG. 2 is a flow chart for illustrating normal operation of the liquid-cooled device system of FIG. 1, according to the present invention; and 
     FIG. 3 is a flow chart for illustrating a coolant removal operation of the liquid-cooled device system of FIG. 1, according to the present invention; and 
     FIG. 4 is a schematic illustration of a general-purpose microprocessor-based or digital signal processor-based system, which can be programmed according to the teachings of the present invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to the drawings, wherein like reference numerals designate identical or corresponding parts throughout the several views, and more particularly to FIGS. 1-4 thereof, there are shown various embodiments of the present invention, as will now be described. 
     FIG. 1 is a block diagram of a liquid-cooled device system, according to the present invention. In FIG. 1, the system includes a liquid-cooled device  104 , such as an electronic device, a coolant removal/distribution network  146 , a coolant pump  138 , an optional heat exchanger (not shown) and a coolant reservoir  140 . The system may further include an optional controller  102 , such as a general-purpose computer or microprocessor, to be described with respect to FIG. 4, coupled to the coolant removal/distribution network  146  for implementing an automatic coolant removal/distribution system. Otherwise, the coolant removal/distribution network  146  may be manually operated. The coolant pump  138 , the optional heat exchanger, the coolant reservoir  140  and the optional controller  102  may be shared by one or more liquid-cooled devices  104  and their respective coolant removal/distribution networks  146 . 
     The coolant removal/distribution network  146  includes a coolant supply path, a coolant return path and a coolant removal path. The coolant supply path includes coolant  116  supplied from the pump  138  either directly mounted on the coolant reservoir  140  or via a coolant supply pipe  142  coupled to the coolant reservoir  140 . The coolant supply path further includes a tee  134  either directly to the pump  138  or coupled to the pump  138  via a pipe, a device coolant supply shut-off valve  114  coupled to the tee  134 , a tee  136  and vacuum relief valve  112  coupled to the device coolant supply shut-off valve  114 , and an optional self-sealing quick disconnect  106  coupled between the tee  136  and the liquid-cooled device  104 . The optional self-sealing quick disconnect  106  may be included in order to implement a toll-less connect/disconnect function to advantageously prevent spillage of residual coolant. 
     The coolant return path includes an optional self-sealing quick disconnect  108  coupled to the liquid-cooled device  104 , a tee  132  coupled to the optional self-sealing quick disconnect  108 , a device coolant return shut-off valve  110  coupled to the tee  132 , a tee  130  coupled to the device coolant return shut-off valve  110 , and coolant  122  returned to the coolant reservoir  140  either directly or through the optional heat exchanger. The optional self-sealing quick disconnect  108  may be included in order to implement a tool-less connect/disconnect function to advantageously prevent spillage of residual coolant. The coolant removal path includes a first portion  124  coupled to the tee  134 , a supply siphon control valve  126  coupled to the first portion  124 , a tee with venturi insert  128  (e.g., model number  621  from Nibco, Inc., Elkhart, IN) coupled between the supply siphon control valve  126 , the tee  130  and a return siphon control valve  120 , and a second portion  118  including a sight glass coupled between the tee  132  and the return siphon control valve  120 . 
     The optional controller  102 , for implementing automatic control functions, remote control functions, etc., is coupled to the return siphon control valve  120 , the device coolant return shut-off valve  110 , the supply siphon control valve  126 , the device coolant supply shut-off valve  114  and the vacuum relief valve  112  to effectuate automatic/remote coolant removal/distribution. In this case, the return siphon control valve  120 , the device coolant return shut-off valve  110 , the supply siphon control valve  126 , and the device coolant supply shut-off valve  114  would be implemented using conventional electronically controlled valves. Otherwise, the return siphon control valve  120 , the device coolant return shut-off valve  110 , the supply siphon control valve  126 , and the device coolant supply shut-off valve  114  would be implemented using conventional manual valves. 
     The present invention uses a venturi effect via the tee with venturi insert  128  to drain/siphon coolant out of the device  104 . The cooling system is a forced-circulation (i.e., pumped) system as shown in FIG.  1 . The present invention adds a coolant removal path between the supply and return paths. The coolant removal path includes the control valve  126  and the tee with a venturi insert  128  installed therein. The siphon side of the venturi tee  128  connects to the device  104  to be drained upstream of its shutoff valve  110 . The vacuum relief valve (e.g., automatic and/or manual valve)  112  also is incorporated to allow air into the coolant lines to replace the coolant that is siphoned out and to facilitate coolant flow to the venturi tee  128 . The outlet of the venturi tee  128  is connected downstream of the device  104  coolant exit shut-off valve  110  by a tee  130 . The tee  132  located just upstream of the shut-off valve  110  is plumbed to the vacuum inlet of the venturi tee  128 . The various shut-off valves  114 ,  110 ,  126  and  120  are used to direct the flow during normal operation and during coolant evacuation. The sight glass located in the second portion  118  of the coolant removal path is used to visually verify that the fluid evacuation process has commenced as well as to determine when to stop the bypass process to minimize over-aeration of the coolant. The optional quick disconnects  106  and  108  are employed to facilitate a “tool-less” device/plumbing removal/connection scheme. 
     In a preferred embodiment of the present invention, one or more pipes connecting the various system components may comprise rigid plumbing, flexible hoses, tubing, etc., or may be eliminated via use of direct coupling of adjacent system components or by use of manifolding techniques to gang or co-locate system components in common blocks, which have been cast or machined with ports and coolant paths to accomplish the system functions disclosed without use of the one or more pipes connecting the various system components. 
     FIG. 2 is a flow chart for illustrating normal operation of the liquid-cooled device system of FIG. 1, according to the present invention. In FIG. 2, at step  202 , the siphon control valves  126  and  120  are closed. At step  204 , the device shut-off valve  110  is opened. At step  206 , the device shut-off valve  114  is slowly opened until air is purged from the system. At step  208 , the supply pump  138  may be operated at full speed, completing the operation. 
     FIG. 3 is a flow chart for illustrating a coolant removal operation of the liquid-cooled device system of FIG. 1, according to the present invention. In FIG. 3, at step  302 , the device shut-off valve  114  is closed. At step  304 , the device shut-off valve  110  is closed. At step  306 , the siphon control valve  120  is opened. At step  308 , the siphon control valve  126  is opened. At step  310 , the sight glass in second portion  118  of the coolant removal path is monitored until air bubbles are observed therein. At step  312 , the siphon control valves  126  and  120  are closed, completing the operation. 
     The present invention may be implemented by an appropriate network of conventional component circuits. The invention may be conveniently implemented using conventional general-purpose computers, microprocessors, digital signal processors, etc., programmed according to the teachings of the present invention, as will be apparent to those skilled in the computer art. Appropriate software can be readily prepared by programmers of ordinary skill based on the teachings of the present disclosure, as will be apparent to those skilled in the software art. 
     The present invention stores information relating to various processes described herein. This information is stored in one or more memories such as a hard disk, optical disk, magneto-optical disk, and/or RAM, for example. One or more databases may store the information used to implement the present invention. The databases are organized using data structures (e.g., records, tables, arrays, fields, graphs, trees, and/or lists) contained in one or more memories or any of the storage devices listed in the discussion of FIG. 4, for example. 
     FIG. 4 illustrates a computer system  402  (e.g., corresponding to the optional controller  102  of FIG. 1) upon which the present invention may be implemented. The computer system  402  may be any one of a personal computer system, a work station computer system, a lap top computer system, an embedded controller system, a microprocessor-based system, a digital signal processor-based system, a hand held device system, a personal digital assistant (PDA) system, a wireless system, a wireless networking system, etc. The computer system  402  includes a bus  404  or other communication mechanism for communicating information and a processor  406  coupled with bus  404  for processing the information. The computer system  402  also includes a main memory  408 , such as a random access memory (RAM) or other dynamic storage device (e.g., dynamic RAM (DRAM), static RAM (SRAM), synchronous DRAM (SDRAM), flash RAM), coupled to bus  404  for storing information and instructions to be executed by processor  406 . In addition, main memory  408  may be used for storing temporary variables or other intermediate information during execution of instructions to be executed by processor  406 . Computer system  402  further includes a read only memory (ROM)  410  or other static storage device (e.g., programmable ROM (PROM), erasable PROM (EPROM), and electrically erasable PROM (EEPROM)) coupled to bus  404  for storing static information and instructions for processor  406 . A storage device  412 , such as a magnetic disk or optical disk, is provided and coupled to bus  404  for storing information and instructions. 
     The computer system  402  also includes input/output ports  430  to couple the computer system  402  to the coolant removal/distribution network  146  to effectuate automatic control thereof, as previously described with respect to FIG.  1 . Such coupling may include direct electrical connections, wireless connections, networked connections, etc., for implementing automatic control functions, remote control functions, etc. 
     The computer system  402  may also include special purpose logic devices (e.g., application specific integrated circuits (ASICs)) or configurable logic devices (e.g., generic array of logic (GAL) or re-programmable field programmable gate arrays (FPGAs)). Other removable media devices (e.g., a compact disc, a tape, and a removable magneto-optical media) or fixed, high-density media drives, may be added to the computer system  402  using an appropriate device bus (e.g., a small computer system interface (SCSI) bus, an enhanced integrated device electronics (IDE) bus, or an ultra-direct memory access (DMA) bus). The computer system  402  may additionally include a compact disc reader, a compact disc reader-writer unit, or a compact disc jukebox, each of which may be connected to the same device bus or another device bus. 
     The computer system  402  may be coupled via bus  404  to a display  414 , such as a cathode ray tube (CRT), liquid crystal display (LCD), voice synthesis hardware and/or software, etc., for displaying and/or providing information to a computer user. The display  414  may be controlled by a display or graphics card. The computer system includes input devices, such as a keyboard  416  and a cursor control  418 , for communicating information and command selections to processor  406 . Such command selections can be implemented via voice recognition hardware and/or software functioning as the input devices  416 . The cursor control  418 , for example, is a mouse, a trackball, cursor direction keys, touch screen display, optical character recognition hardware and/or software, etc., for communicating direction information and command selections to processor  406  and for controlling cursor movement on the display  414 . In addition, a printer may provide printed listings of the data structures, information, etc., or any other data stored and/or generated by the computer system  402 . 
     The computer system  402  performs a portion or all of the processing steps of the invention in response to processor  406  executing one or more sequences of one or more instructions contained in a memory, such as the main memory  408 . Such instructions may be read into the main memory  408  from another computer readable medium, such as storage device  412 . One or more processors in a multi-processing arrangement may also be employed to execute the sequences of instructions contained in main memory  408 . In alternative embodiments, hard-wired circuitry may be used in place of or in combination with software instructions. Thus, embodiments are not limited to any specific combination of hardware circuitry and software. 
     As stated above, the system  402  includes at least one computer readable medium or memory programmed according to the teachings of the invention and for containing data structures, tables, records, or other data described herein. Examples of computer readable media are compact discs, hard disks, floppy disks, tape, magneto-optical disks, PROMs (EPROM, EEPROM, Flash EPROM), DRAM, SRAM, SDRAM, etc. Stored on any one or on a combination of computer readable media, the present invention includes software for controlling the computer system  402 , for driving a device or devices for implementing the invention, and for enabling the computer system  402  to interact with a human user. Such software may include, but is not limited to, device drivers, operating systems, development tools, and applications software. Such computer readable media further includes the computer program product of the present invention for performing all or a portion (if processing is distributed) of the processing performed in implementing the invention. 
     The computer code devices of the present invention may be any interpreted or executable code mechanism, including but not limited to scripts, interpreters, dynamic link libraries, Java classes, and complete executable programs. Moreover, parts of the processing of the present invention may be distributed for better performance, reliability, and/or cost. 
     The term “computer readable medium” as used herein refers to any medium that participates in providing instructions to processor  406  for execution. A computer readable medium may take many forms, including but not limited to, non-volatile media, volatile media, and transmission media. Non-volatile media includes, for example, optical, magnetic disks, and magneto-optical disks, such as storage device  412 . Volatile media includes dynamic memory, such as main memory  408 . Transmission media includes coaxial cables, copper wire and fiber optics, including the wires that comprise bus  404 . Transmission media also may also take the form of acoustic or light waves, such as those generated during radio wave and infrared data communications. 
     Common forms of computer readable media include, for example, hard disks, floppy disks, tape, magneto-optical disks, PROMs (EPROM, EEPROM, Flash EPROM), DRAM, SRAM, SDRAM, or any other magnetic medium, compact disks (e.g., CD-ROM), or any other optical medium, punch cards, paper tape, or other physical medium with patterns of holes, a carrier wave (described below), or any other medium from which a computer can read. 
     Various forms of computer readable media may be involved in carrying out one or more sequences of one or more instructions to processor  406  for execution. For example, the instructions may initially be carried on a magnetic disk of a remote computer. The remote computer can load the instructions for implementing all or a portion of the present invention remotely into a dynamic memory and send the instructions over a telephone line using a modem. A modem local to computer system  402  may receive the data on the telephone line and use an infrared transmitter to convert the data to an infrared signal. An infrared detector coupled to bus  404  can receive the data carried in the infrared signal and place the data on bus  404 . The bus  404  carries the data to main memory  408 , from which processor  406  retrieves and executes the instructions. The instructions received by main memory  408  may optionally be stored on storage device  412  either before or after execution by processor  406 . 
     The computer system  402  also includes a communication interface  420  coupled to bus  404 . Communication interface  420  provides a two-way data communication coupling to a network link  422  that may be connected to, for example, a local network  424 . For example, communication interface  420  may be a network interface card to attach to any packet switched local area network (LAN). As another example, communication interface  420  may be an asymmetrical digital subscriber line (ADSL) card, an integrated services digital network (ISDN) card or a modem to provide a data communication connection to a corresponding type of telephone line. Wireless links may also be implemented via the communication interface  420 . In any such implementation, communication interface  420  sends and receives electrical, electromagnetic or optical signals that carry digital data streams representing various types of information. 
     Network link  422  typically provides data communication through one or more networks to other data devices. For example, network link  422  may provide a connection to a computer  426  through local network  424  (e.g., a LAN) or through equipment operated by a service provider, which provides communication services through a communications network  428 . In preferred embodiments, local network  424  and communications network  428  preferably use electrical, electromagnetic, or optical signals that carry digital data streams. The signals through the various networks and the signals on network link  422  and through communication interface  420 , which carry the digital data to and from computer system  402 , are exemplary forms of carrier waves transporting the information. The computer system  402  can transmit notifications and receive data, including program code, through the network(s), network link  422  and communication interface  420 . 
     Although the present invention is described in terms of coolant removal from liquid-cooled electronic devices, the present invention is applicable to coolant removal from other types of liquid-cooled devices, such as transmissions, radiators, refrigerators, etc., as will be appreciated by those of ordinary skill in the relevant art(s). 
     Although the present invention is described in terms of the vacuum relief valve  112  being coupled to the tee  136  and the second portion  118  of the coolant removal path including the sight glass connected to the tee  132 , as shown in FIG. 1, the vacuum relief valve  112  could be coupled to the tee  132  and the second portion  118  could be connected to the tee  136 , to allow for system implementations wherein the liquid-cooled device is provided at a lower level than the optional quick disconnects  108  coolant outlet, as will be appreciated by those of ordinary skill in the relevant art(s). 
     Numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein.