An Experimental Study and Numerical Simulation of Two-phase Flow of Cryogenic Fluids through Micro-channel Heat Exchanger

The design, fabrication, testing and analysis of a microchannel heat exchanger, a key component for a microminiature Joule-Thomson Cryogenic Refrigerator is described. Results show that the heat exchanger can be fabricated efficiently and economically with the existing manufacturing technology. The heat exchanger was tested to be mechanically robust and durable under high pressure operating condition. “Choking” did not occur in the micro-channels of the heat exchanger. The thermal performance is excellent, providing the rapid cooling as designed. A numerical code is developed both to interpret the data and to provide some sensitivity study and assessment on the performance characteristics of the heat exchanger. Furthermore, this code will be utilized as a design tool for optimizing the performance of next generation planar heat exchangers.