The Experimental Research And Theoretical Analysis Of Thermosyphon's Heat Transfer Performance

The heat pipe is high performance heat transfer device with phase change. As a new energy-saving technology, it has been applied in so many industrial sectors since the end of 1970's. The carbon steel-water heat pipe, a new invention with the simple technical process and low cost, brings much progress in the heat recovery of the heat pipe heat exchanger, in which the flue-gas temperature is below 350℃. The advantages of two-phase closed thermosyphon are that small heat resistance, react fast, the structure is simple, the manufacture is convenient, the cost is cheap, and the heat transfer performance is good, without capillary limit, the work is dependable, so thermosyphons can be the efficient heat transfer components in every variety heat transfer equipments on the ground, and their applied realm increase with each passing day. They have developed huge superiority in general use of thermal energy and techniques of waste heat recovery in every industry.As it is known, there are many factors affect thermosyphon's performance, including geometrical sizes, obliquity, the physical properties of the work liquid, working temperature inside the tube and so on. Analyzing the heat transfer mechanism of thermosyphon, this article introduce lumped method and the analysis of heat resistance network. Furthermore, using computer to calculate the important frame parameters and optimize the heat exchanger. Especially use this computational method to calculate the length allotment between evaporator section and condenser section under the condition that some other basic frame parameters are all certain, so that can strengthen thermosyphon's heat transfer ability in the heat pipe heat exchanger.We designed and manufactured a set of experimental device to test the heat transfer characteristics of carbon steel- water two-phase closed thermosyphon, including its start performance, isothermal performance, the performance of thermosyphon surface temperature's fluctuation, the influences of working temperature and obliquity, etc. Furthermore, we got the primary theoretical analysis. Total experiments are divided into three parts, including the experimental research of common thermosyphon's heat transfer performance, enhancing boiling heat transfer in the thermosyphon and curving thermosyphon's heat transfer performance. Through experiments to learn aboutthermosyphon's heat transfer performance and the relation of the heat transfer power of thermosyphon between working temperature and obliquity, then find out the suitable working environment.By computation and experiments of thermosyphons, enrich the theories and experimental researches of heat pipe, provide theoretical and technical supports to the heat pipe type heat exchanger and heat pipe manufacturers.