Experimental Study On Transient Boiling Measuring Technique

The content of this thesis is the experimental research of transient boiling phenomena, which are the hot spot that was formed in the boiling heat transfer field since 1 970s.On the basis of the predecessors?experiment, the author set up the experimental apparatus of transient boiling using the surface thermocouple and thin-film thermocouple as sensors. Using data-collecting system developed by ourselves and controlling different parameters, the author monitors the phenomenon of transient boiling and measures the temperature signal. In order to verify the experimental results, numerical simulation of the steady temperature field is carried out before the transient experiment. Temperature field is rectified by comparison of data between the simulation and experiment. By analyzing and processing bountiful experimental data collected in short time, the curves of temperature variation of fast transient nucleate boiling are then drawn with wavelet analysis theory. Also by setting up the mathematical model and applying the temperature variation curves to this mathematical model, heat flux density can be resolved.We employed the saturated water as boiling medium to make tests with different liquid level. Some conclusions were obtained and verified.