Abstract:
Disclosed is an apparatus ( 10 ) for simulation of heat generation of a heat-generating electronic component. The apparatus includes a heat-transfer simulation device ( 110 ), a base ( 120 ) and at least one supporting post ( 150 ). The base is made of a heat-insulation material, and defines therein a recess ( 122 ). The heat-transfer simulation device is used for simulating heat generation from a heat-generating electronic component. The supporting post supportively mounts the heat-transfer simulation device within the recess defined in the base. A method of evaluating heat removal capacity of a heat dissipation device is also disclosed based on this apparatus.

Description:
FIELD OF THE INVENTION 
     The present invention relates to apparatuses for evaluation of heat removal capacity of heat dissipation devices, and more particularly to an apparatus for simulation of heat generation of a particular heat-generating electronic component with reduced overall heat loss so that the evaluation process can be carried out with improved accuracy. 
     DESCRIPTION OF RELATED ART 
     It is well known that heat is produced by heat-generating electronic components during their normal operations. For example, a central processing unit (CPU) mounted within a computer enclosure generates a large amount of heat. The generated heat, if not adequately removed from the enclosure, will noticeably degrade the performance of the CPU. Thus, a heat dissipation device is required for cooling of the CPU. 
     When a heat dissipation device is used to remove excessive heat from a particular heat-generating electronic component (e.g. a CPU), the heat dissipation device should be evaluated beforehand to ensure that it has an adequate heat removal capacity for taking away the heat generated by the CPU effectively and efficiently, especially when the heat dissipation device is a new design. In practice, the evaluation process is often carried out using a heat-transfer simulation device to simulate the heat generation of a CPU. To reduce heat loss, the heat-transfer simulation device generally is disposed on a supporting base, with only a heat-emitting surface of the heat-transfer device being exposed for thermally contacting the heat dissipation device to be evaluated. A heating device is then employed to input thermal energy to the heat-transfer simulation device, which in turn, transfers the thermal energy to the heat dissipation device through the heat-emitting surface. 
     In this evaluation process, the thermal energy inputted by the heating device is deemed as being absorbed and dissipated entirely by the heat dissipation device. The maximum amount of thermal energy that the heat dissipation device can dissipate is accordingly used to evaluate the heat removal capacity of the heat dissipation device. However, since the heat-transfer simulation device is directly seated in and contacts with the supporting base, a portion of the thermal energy inputted by the heating device will also be absorbed and dissipated by the supporting base, even if the supporting base is made of a heat-insulation material. As such, the heat actually dissipated by the heat dissipation device is much less than the thermal energy as being originally inputted by the heating device. The heat removal capacity of the heat dissipation device, if directly based on the thermal energy inputted by the heating device without considering the heat loss associated with the supporting base, will result in overly optimistic evaluation results. For example, if the thermal energy inputted by the heating device is 80 watts while the heat loss associated with the supporting base is 10 watts, then the heat actually absorbed and dissipated by the heat dissipation device will be 70 watts. Thus, an error of 10 watts will exist in the above-mentioned evaluation process. 
     In view of the above-mentioned disadvantage, it is desirable to provide an apparatus which can be applied to evaluate the heat removal capacity of the heat dissipation device with improved measurement accuracy. 
     SUMMARY OF THE INVENTION 
     The present invention in one aspect relates to an apparatus for simulation of heat generation of a heat-generating electronic component. The apparatus includes a base, a heat-transfer simulation device and at least one supporting post. The base is made of a heat-insulation material, and defines a recess therein. The heat-transfer simulation device is used for simulating heat generation of the heat-generating electronic component. The supporting post supportively mounts the heat-transfer simulation device within the recess defined in the base. The heat-transfer simulation device does not have a physical contact with the base. 
     The present invention in another aspect, relates to a method of evaluating heat removal capacity of a heat dissipation device. The method includes the following steps: (1) providing a base made of a heat-insulation material, wherein the supporting base defines therein a recess; (2) providing a heat-transfer simulation device for simulation of heat generation of a heat-generating electronic component; (3) providing at least one supporting post for supportively mounting the heat-transfer simulation device within the recess defined in the base, wherein the heat-transfer simulation device does not have a physical contact with the base; (4) maintaining the heat dissipation device in thermal contact with the heat-transfer simulation device; (5) inputting thermal energy to the heat-transfer simulation device; and (6) measuring temperature of the heat-transfer simulation device to obtain the heat removal capacity of the heat dissipation device according to the measured temperature and the inputted thermal energy. 
     Other advantages and novel features of the present invention will become more apparent from the following detailed description of preferred embodiments when taken in conjunction with the accompanying drawings, in which: 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded, isometric view of an apparatus for simulation of heat generation of a particular heat-generating component in accordance with an embodiment of the present invention; 
         FIG. 2  is an exploded, isometric view of a heat-transfer simulation device according to the embodiment of  FIG. 1 ; 
         FIG. 3  is a top plan view of a supporting base according to the embodiment of  FIG. 1 ; 
         FIG. 4  is an assembled view of the apparatus of  FIG. 1 ; 
         FIG. 5  is a cross-sectional view of the apparatus of  FIG. 4 ; and 
         FIG. 6  is similar to  FIG. 4 , with a gap between the supporting base and the heat-transfer simulation device being filled with a soft material. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  illustrates an apparatus  10  for simulation of heat generation of a heat source in accordance with an embodiment of the present invention. The apparatus  10  can be suitably used to evaluate the heat removal capacity of a particular heat dissipation device (not shown). The apparatus  10  in this embodiment is especially suitable for simulating heat generation of a heat-generating electronic device such as a central processing unit (CPU) of a computer. An evaluation process can be carried out on the apparatus  10  to evaluate whether this particular heat dissipation device has an adequate heat removal capacity for cooling the CPU. 
     The apparatus  10  includes a heat-transfer simulation device  1110 , a supporting base  120 , a pair of electrical heaters  130 , a pair of thermocouples  140 , and four supporting posts  150 . The supporting base  120  is made of a heat-insulation material, such as plastics, rubbers, acrylonitrile butadiene styrene (ABS), bakelite, or the like. The supporting base  120  defines a rectangular (or square) recess  122  at a central portion thereof for reception of the heat-transfer simulation device  110  therein. A pair of first guiding holes  127  is defined from a corner of the supporting base  120  to communicate with the recess  122 , thus allowing insertion of the electrical heaters  130 . A pair of second guiding holes  128  is also defined from the corner to communicate with the recess  122 , allowing the insertion of the thermocouples  140 . The first guiding holes  127  are located below the second guiding holes  128 . Each of the supporting posts  150  has a large length-to-diameter ratio. In this embodiment, the supporting posts  150  are in the form of a plurality of screws. 
     With reference to  FIG. 2 , the heat-transfer simulation device  110  includes a contacting plate  112 , a core element  114  and a heat-receiving block  116 . The contacting plate  112  has an upper surface  112   a . In the contacting plate  112 , temperature detecting points A and B are established, wherein the temperature detecting point A is located near a central portion of the contacting plate  112  while the temperature detecting point B is located near a lateral side of the contacting plate  112 . “Temperature detecting point” used herein means a physical location that represents a point for which temperature control is desired. In order to detect the temperatures at the temperature detecting points A and B, a pair of retention holes  112   b  are correspondingly defined from a front side of the contacting plate  112  wherein each retention hole  112   b  receives and positions one of the thermocouples  140  therein. 
     The core element  114  is located between the contacting plate  112  and the heat-receiving block  116 . The core element  114  has a much smaller size than the contacting plate  112  so as to simulate the heat generation of a CPU in a more accurate manner. The heat-receiving block  116  defines a pair of mounting holes  116   a  from a front side thereof wherein each mounting hole  116   a  receives and positions one of the electrical heaters  130  therein. 
     Referring now to  FIG. 3 , the supporting base  120  defines at a top surface thereof four mounting holes  124 . The mounting holes  124 , which cooperatively surround the recess  122  defined in the supporting base  120 , are used to mount the heat dissipation device to be evaluated. Additionally, four threaded holes  125  and a central hole  126  are defined from a bottom surface of the supporting base  120  to communicate with the recess  122 , as also shown in  FIG. 5 . The central hole  126  is surrounded by the four threaded holes  125 . The central hole  126  is designed to allow a detaching tool, for example, a pin (not shown) to insert into from the bottom surface of the supporting base  120  and facilitate detachment of the heat-transfer simulation device  110  from the recess  122  of the supporting base  120 . 
     With reference to  FIGS. 4-5 , in assembly, the heat-transfer simulation device  110  is mounted within the recess  122  of the supporting base  120  by the four supporting posts  150  engaging with the supporting base  120  in the four threaded holes  125 . The upper surface  112   a  of the contacting plate  112  protrudes slightly above the top surface of the supporting base  120  so that the heat dissipation device to be evaluated can be maintained in intimate thermal contact with the contacting plate  112 . A gap  170  is formed between an inner circumferential surface of the recess  122  and an outer circumferential surface of the heat-transfer simulation device  110 , whereby the heat-transfer simulation device  110  is not brought into direct contact with the supporting base  120 . 
     The electrical heaters  130  are guided through the first guiding holes  127  of the supporting base  120  and are ultimately inserted into and positioned in the mounting holes  116   a  defined in the heat-receiving block  116 . The electrical heaters  130  and the heat-receiving block  116  preferably have a layer of thermal interface material therebetween so as to increase heat transfer efficiency. The thermocouples  140  are guided by the second guiding holes  128  of the supporting base  120  and then inserted into and positioned in the retention holes  112   b  defined in the contacting plate  112 . 
     Then, the heat dissipation device to be evaluated is thermally connected to the upper surface  112   a  of the contacting plate  112 . Thermal energy is inputted to the heat-receiving block  116  by the electrical heaters  130 . The thermal energy then is transferred to the core element  114  from the heat-receiving block  116 . The core element  114  absorbs the thermal energy from the heat-receiving block  116  and then spreads the thermal energy to the above contacting plate  112 . The contacting plate  112  then transfers the thermal energy, via the upper surface  112   a , to the heat dissipation device where the thermal energy is finally dissipated into ambient air. In this embodiment, the core element  114  and the contacting plate  112  cooperatively simulate heat generation of a CPU. 
     During the evaluation process, the thermocouples  140  are used to detect the temperatures at the temperature detecting points A and B when the thermal equilibrium is established between the heat dissipation device and the heat-transfer simulation device  110 . The heat dissipation device can be evaluated based on the temperature at the temperature detecting point A, or the temperatures at the temperature detecting points A and B. For example, if the heat dissipation device is evaluated based merely on the temperature at the temperature detecting point A, the temperature Tcase at the temperature detecting point A is first obtained by one of the thermocouples  140 . If the detected temperature Tcase at the temperature detecting point A is lower than a predetermined level, for example, 50° C., then the electrical heaters  130  gradually increase the amount of thermal energy inputted to the heat-transfer simulation device  110 , until the temperature Tcase at the temperature detecting point A reaches the predetermined level (i.e. 50° C.). At this moment, the thermal energy inputted by the electrical heaters  130  is used to evaluate the heat removal capacity of the heat dissipation device. 
     In the evaluation process, the heat-transfer simulation device  110 , as supported by the supporting posts  150 , is “suspended” (i.e. held) in the recess  122  of the supporting base  120  and is not brought into direct contact with the supporting base  120 ; thus, the thermal energy inputted to the heat-transfer simulation device  110  is effectively prevented from being conducted or transferred to the supporting base  120  and hence the heat loss associated with the supporting base  120  in the whole evaluation process is greatly reduced, thereby increasing the measurement accuracy for the heat dissipation device. The gap  170  formed between the supporting base  120  and the heat-transfer simulation device  110  may optionally be filled with soft, heat-insulation material such as a layer of cotton wadding  180 , as shown in  FIG. 6 , so as to steadily position the heat-transfer simulation device  110  in the recess  122 . 
     It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.