Numerical Study Of The Effects Of Parameters In A Closed Loop Pulsating Heat Pipe

Pulsating heat pipe is a kind of highly efficient thermal components with theadvantages of having small size, low cost, and high performance, which graduallyattracts the attention of researchers in various fields. A large number of thermalperformance experiments have proved that the thermal characteristic of pulsatingheat pipe is affected by turns，inclination angle，diameter and other various factors inthe process of starting and stable operation. Through the existing visualizationexperiment, researchers observe the different flow patterns in the state of starting andstable operation.In accordance with the existing experimental phenomenon and data, this paperbuilds a mathematical-physical model of closed loop pulsating heat pipe with flowcharacteristic combined. The model includes several vapor and liquid slugs, byanalyzing each slug respectively, equations of conservation of energy, conservationof momentum and conservation of quality control are established. Under Fortranenvironment, the program is written and then adopts the first-order differentialmethod to solve the mathematical-physical model, and the variation law of flow andheat transfer for working fluid is simulated.Numerical simulation results show that the working fluid circulates steadilyalong the pipeline in the counterclockwise direction. There may be back orstagnation in parts of the pipeline, but the overall flow does not change. The paperalso discusses the number of turns, inclination angle and diameter that affect theflow characteristic. If other conditions are same, the pulsating heat pipe with biggerdiameter has better performance. Inclination angle and the number of turnscodetermine the flow pattern of working fluid.