EXPERIMENTAL RESEARCH ON FINNED TUBE HEAT EXCHANGER WITH DIFFERENT PITCH FOR A JOULE-THOMSON COOLER START-UP TIME

The starting-up process of a J-T cooler is unsteady process.There is still a large error in the simulation of a J-T cooler’s start-up process until now.Establishing the experimental model of different pitch finned tube heat exchanger to verify the effect on a J-T cooler start-up time.The experimental results show that the change of a heat exchanger fin pitch has impact on a J-T cooler start-up time，and the impact is not a linear relationship，there is an inflection point.In the model of this paper，the optimum pitch of fin tubes is 0.2 mm.The study is useful for the design of the J-T cooler.