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Phase Change Inhibited Heat Transfer Technology (abbreviation: PCI Heat Transfer Technology)

A new technology for heat transport!

It is different from the three basic heat transfer modes, i.e. convection, conduction and radiation.

It subverts the classical heat transfer laws.

It creates a unique effect of heat transport.

In the academic field of heat transfer, it is generally believed that the use of phase transition of the working fluid, such as boiling and condensation, can greatly improve the heat transport capability of the heat transfer device, and the heat pipe is a high efficient heat transfer device based on this principle.

Since its birth, the heat pipe has been widely used in many industrial fields, which involve heat transport or dissipation. However, some inherent limitations, such as dryout phenomenon, in the application of heat pipe are gradually discovered, which prevent its application in the field of higher heat transport capability.

In the PCI heat transfer technology, a single phase homogeneous system is established in the heat transport device through the special design and fabrication. Heat transport process did not use of phase change, but consciously inhibited the phase change occurrence of the working fluid in the heat transport process, and a special heat transfer mechanism to achieve an efficient heat transport, but also overcome the boiling limit in heat pipe.

Mr. Cheechiang Sae Lee first in 2005 discovered the phenomenon of the phase change inhibited heat transfer. And late the abnormal phenomenon has been repeated in his and others laboratories. After more than a decade of exploration, experiment and application, Mr. Lee led his R & D team to continuously develop and improve the PCI heat transfer technology. Based on years of experience accumulation, at present, a set of unique design system for PCI heat transfer devices has been constructed.

PCI heat transfer device has two types of structures, i.e, tube type and plate type. PCI device with plate structure is an integrated heat transport / heat sink device. Recently two type PCI devices have realized the scale of commercial applications.

The products using PCI heat transfer technology, not only could make heat transport or heat sink devices, but also could be applied to the overall heat dissipating system, such as the constant temperature cooling system, pressurized water reactor cooling system, etc..

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Unique operating mechanism

The unique heat transport phenomenon on the PCI heat transfer device can not be explained by the classical heat transfer theory. The mechanism of phase change inhibited heat transfer is different from that of heat conduction, convection and radiation, and its heat transport capability is not dependent on the heat carried by the cooling medium in the move process. Therefore, the heat transfer mode of PCI technology neither requires the power source, such as gravity, rainbow suction, to drive the working fluid, nor does require to consider the inner diameter of the channels and the flow rate, velocity of the working fluid in the channels.

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PCI heat transfer technology, compared with the traditional heat transfer mode ,for example, heat pipe, has many advantages, which has a significant "two high" characteristics, namely the high heat transport speed and high heat flux.

high heat transport speed

Let us introduce an experiment for demonstrating PCI heat transfer devices with high heat transport rates. Take an arc torch with a thermal power of up to kilowatt class to burn the PCI heat transfer device with thickness 2 mm on the surface of 1cm2 or less.

Once the heat source is withdrawn, the hand can immediately touch the back of the device, while the device temperature at the far end of the distance from the heat source is higher than that of the near end. If the torch temperature is about 500 ℃, at the same time, the bare hand can touch the back of the device.

At present, any other excellent heat transfer device can not be done this experiment. Due to the limitations of the measurement methods, although this experiment is very intuitive, but there is still a lack of quantitative test data. Estimated heat transport time can be reached in the millisecond level. In fact, it is because of its high heat transport speed to make the heat channel of the device do not appear dryout phenomenon.

high heat flux

The heat flux of the heat transport process is the heat power by the unit area of the heating surface. With the increasing power of various new electronic devices, but the size is smaller and smaller, the thermal power of the heating surface is higher and higher, that is, the heat flux will reach a very high value. The existing heat transfer technologies can not meet the needs of Hi-Tech growing, and has become the bottleneck of the development of new products.

We can estimate the heat flux in the above mentioned experiment. By using a thin film heater or a large power torch the heat flux of PCI device can be reached  100-1000 W/cm2. We hope that PCI heat transfer technology could provide a perfect thermal management solution for numerous Hi-Tech projects.

Good orientation adaptability.

Good temperature homogeneity.

Good environment adaptability. The PCI devices could start under the ambient temperature of - 20℃.

Easy to manufacture, adjust and maintain. 

Recently the PCI products of Karhe Technology has been successfully applied in many fields and has been commercialized. The successful application cases are as follows.

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Plate-type

Radiator for microprocessor


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Tube-type

Concentrating solar heat collector

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Boiler for hot water

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Air conditioner