Annular Heat Pipe

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Types of Heat Pipes Two-Phase Closed Thermosyphon Capillary-Driven Heat Pipe Annular Heat Pipe Vapor Chamber Rotating Heat Pipe Gas-Loaded Heat Pipe Loop Heat Pipe Capillary Pumped Loop Heat Pipe Pulsating Heat Pipe Monogroove Heat Pipe Micro and Miniature Heat Pipes Inverted Meniscus Heat Pipe Nonconventional Heat Pipes

The annular heat pipe is similar to the conventional capillary-driven heat pipe in many ways ^[1][2]. The main difference between the two is that the cross-section of the vapor space in an annular heat pipe is annular instead of circular (Fig. 1) ^[3][4]. This enables the designer to place wick material both on the inside of the outer pipe and on the outside of the inner pipe. In this manner, the surface area for heat input and output can be significantly increased without increasing the outer diameter of the pipe. Therefore, the capillary limit of the annular heat pipe is greater than that of a conventional heat pipe having the same outer dimensions. The annular heat pipe has been used as an isothermal furnace, with excellent results due to its temperature flattening capabilities and fast response time to a cold charge. This type of heat pipe can also be used to connect two circular cross-section heat pipes end-to-end by inserting the circular heat pipe into the inner pipe.

References

1. ↑ Faghri, A., 2012, "Review and Advances in Heat Pipe Science and Technology," Journal of Heat Transfer, 134(12), 123001. http://dx.doi.org/10.1115/1.4007407
2. ↑ Faghri, A., 1995, Heat Pipe Science and Technology, 1st ed., Taylor & Francis, Washington, D.C.
3. ↑ Faghri, A., and Thomas, S., 1989, "Performance Characteristics of a Concentric Annular Heat Pipe: Part I-Experimental Prediction and Analysis of the Capillary Limit," Journal of Heat Transfer, 111(1-4), 844-850.
4. ↑ Faghri, A., 1989, "Performance Characteristics of a Concentric Annular Heat Pipe: Part II-Vapor Flow Analysis," Journal of Heat Transfer, 111(4), 851-857.