The present invention relates generally to heat exchange apparatuses using fluidized bed technology. More particularly, the present invention relates to active type coolers for cooling of electronic devices. The present invention is particularly, but not exclusively, useful for cooling systems for regulating the temperature of electronic components of desktop computers.
The regulation of the temperature due to heat generated inside the housing of an electronic device is an important consideration during the design of an electronic device. Cooling is important because if left unchecked, heat can cause electronic devices to malfunction during use or lead to premature device failure. As improvements in processor size and speed occur, the amount of heat generated by the larger and faster processors also increases. Additionally, improved processors require larger power supplies and auxiliary components that generate increased amounts of heat and require improved systems for heat removal.
Another factor that aggravates the need for improved heat removal cooling systems is the trend towards making computing devices smaller. The trend toward smaller electronic devices having larger, faster processors renders the traditional heat removal cooling systems inadequate for several reasons.
In order to enhance the cooling capacity of a cooling device, an electrically powered blowers of different types such as axial, radial or crossflow are often mounted within or on top of a heatsink of the cooling device. In operation, the blower forces air to pass over fins of the heatsink, thus, cooling the heatsink by enhancing the heat transfer from the fins into the ambient air.
There are known devices of these types. For example, U.S. Pat. No. 6,698,505 “Cooler for an Electronic Device” comprises a crossflow blower, No. 6,152,214 “Cooling Device and Method” comprises an axial blower and No. 6,244,331 “Heatsink with Integrated Blower for Improved Heat Transfer” and No. 6,664,673 “Cooler for Electronic Devices” comprise a radial blower.
Due to the modern requirements for cooling devices, especially in respect to a combination of the thermal efficiency and an available space, the further enhancement of the cooling efficiency providing by the increasing of the blower supplied power (airflow increasing) and/or by the sufficient developing of the heat exchanging surface of the heatsink.
However, mentioned increasing of the supplied power and the heat exchanging surface became in contradiction with the modern requirements for cooling devices. On the one hand, according to the requirements the supplied power is limited. And on the other hand, the increasing of the heat exchanging surface of the heatsink leads to the increasing of the volume and/or mass properties of the cooling devices and exceed the space limitations.
The other way to increase sufficiently the thermal efficiency of cooling devices is the use one of heat exchange intensification methods such as fluidized bed technology.
The fluidized bed (including miniaturized) technology is widely used commercially in chemical, pharmaceutical, food and other fields of industry. Usually fluidized bed technology used for drying, coating, mixing and heating/cooling a product powder.
There are known devices and apparatuses using fluidizing bed technology, for example, U.S. Pat. No. 5,954,000 “Fluid Bed Ash Cooler”, No. 6,214,065 “Method of Operating a Fluidized Bed Reactor System, and Fluidized Bed Reactor System” and No. 6,451,274 “Depleted UF6 Processing Plant and Method for Processing Depleted UF6”.
All mentioned devices comprise a fluidized bed chamber partially filled up with particulate solids and a source of airflow. When an air is passed upwards through a bed of particles a point is reached when the upward drag force exerted by the air on the particles is equal to the apparent weight of particles in the bed. At this point the particles are lifted by the air, the separation of the particles increases, and the bed becomes fluidized. But, there are non known designs of coolers for electronic components using fluidized bed technology.
It would be desirable for the given space provide the fluidized bed cooler for electronic components that would overcome these problems associated with the contradiction between the necessity of further enhancement of the cooling efficiency of cooling devices and compliance with the space limitations at the same time.
Accordingly, it is an object of the present invention to provide a fluidized bed cooler for electronic components, which is capable to improve significantly the thermal efficiency of cooling devices.
In order to achieve this task, the fluidized bed cooler for electronic components comprises a blower and a heatsink with a base and heat exchanging means. The blower comprises an electric drive with a stator and a magnetized rotor, an impeller and a casing with blower inlet and outlet. The base is made as a heat spreader with a plate and providing a thermal contact with the electronic components and the heat exchanging means. The heat exchanging means are surround by a housing thus forms a fluidized bed chamber with inflow and outflow side openings. The fluidized bed chamber partially filled up with particulate solids and covered from both openings by intake and outtake grilled structures. The blower hydraulically connected by the inlet with the outflow side opening, so cooling gas flows through the inflow side opening, the fluidized bed chamber thus fluidizing the particulate solids, the outflow side opening, the blower inlet, the impeller and the blower outlet in a series way.
The heat exchanging means are spaced apart from each other at a distance of at least 20 mean sizes of the particulate solids.
There are two embodiments of the present invention. First, heat exchanging means may be made as parallel vertical located fins surrounding by a box-shaped housing. For this embodiment there are two options of the base plate location. According to the first option the plate is located horizontally at a bottom part of the cooler thus serving for horizontal located electronic components. And, according to the second option, the plate is located vertically at a side part of the cooler thus serving for vertical located electronic components.
According to the second embodiment of the present invention, the heat exchanging means are made as radial vertical located fins surrounding by a cylinder-shaped housing. There are two options of the base plate location, also. First, the plate is located horizontally at a bottom part of the cooler thus serving for horizontal located electronic components. And second, the plate may locate vertically at a side part of the cooler thus serving for vertical located electronic components.
The heat exchanging means and the housing may further comprise electro-magnetic coils with a controller creating an alternating motive electromagnetic field and the particulate solids are made from magnetizable material thus the particulate solids realizing a recirculation motion inside the fluidized bed chamber.
The foregoing and other objectives, features and advantages of the invention will be more readily understood upon consideration of the following detailed description of the invention, taken in conjunction with the accompanying drawings.
Preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings.
The fluidized bed cooler I for electronic components 2 (
The impeller 10 is made as a radial type impeller, thus the blower 3 is the radial type blower. This type of the blower 3 is the most effective for creating a required pressure to support the fluidized bed process. The electric drive 7 may be used of any conventional type, for example brushless DC flat electric motor. The base 5 is made as a heat spreader 14 with a plate 15 and provides a thermal contact with the electronic components 2 and the heat exchanging means 6. The heat exchanging means 6 are surrounded by a housing 16 thus forms a fluidized bed chamber 17 with inflow 18 and outflow 19 side openings. The fluidized bed chamber 17 partially filled up with particulate solids 20 and covered from both openings 18 and 19 by intake 21 and outtake 22 grilled structures. The blower 3 hydraulically connected by the inlet 12 with the outflow side opening 19, so cooling gas flows through the inflow side opening 18, the fluidized bed chamber 17 thus fluidizing the particulate solids 20 (
For the best fluidized bed process the heat exchanging means 6 are spaced apart from each other at a distance of at least 20 mean sizes of the particulate solids 20. The material of the particulate solids 20 is not very important and may be sand, for example.
There are two embodiments of the present invention. First, heat exchanging means 6 may be made as parallel vertical located fins 23 surrounding by a box-shaped housing 27 (
According to the second embodiment of the present invention (
For both embodiments the heat exchanging means 6 and the housing 16 may further comprise electromagnetic coils 30 (
The fluidized bed cooler I for electronic components 2 operates in the following way. When an electric power supplied to the stator 8 of the electric drive 7, the alternative electro-magnetic field is created. This electromagnetic field controlled by the controllers (not shown on Figs.) interacts with a magnetic field created by the magnetized rotor 9. In result of this interaction the magnetized rotor 9 and, therefore the impeller 10 of the blower 3, starts to rotate. Cooling gas starts moving and flow through the fluidized bed chamber 17 thus fluidizing the particulate solids 20. Heat generated by electronic components 2 transfers to the base 5 due its thermal contact and spreads to the heat exchanging means 6. Cooling gas flow the heat exchanging means 6 and the intensive process of heat exchange take place.
Well known, that during the fluidized bed process a heat exchange coefficient (heatsink-cooling gas) is more than 10 times in comparison with the same parameter for known coolers for electronic components. At the same time, the fluidized bed cooler according to the present invention in relation to the particulate solids size require more spacing between the heat exchanging means, at least 5 times in comparison with known coolers for electronic components. Therefore, for the same constrains comparative to conventional technology, including available space, mass etc. the fluidized bed cooler providing at least double in thermal efficiency.
The present application claims the benefit of priority of U.S. Provisional Patent Application No. 60/615,004, filed 10/02/2004 for Edward Lopatinsky and Lev Fedoseyev the entire content of which is incorporated herein by reference.
Number | Date | Country | |
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60615004 | Oct 2004 | US |