Research On The Effects Of Rotor Hands On The Performance Of Self-Cleaning And Heat Transfer Enhancement In Shell-and-Tube Exchanger

The shell-and-tube exchanger is widely applied in every industry and field, especially in the condenser of the coal-fired power plant. But because of the much scaling in short time and its own structure, the efficiency of shell-and-tube exchanger is reduced in long working time. The traditional way of solving this problem is adding the chemicals into the water or cleaning the tube by the machine, which may waste the energy and pollute the environment. In order to deal with the problem better, the new rotor device is designed to self-clean the tube and enhance heat transfer.Strand-rotors including rotors, supporting shaft, limit stop and supporting frame, are fixed in the tube of shell-and-tube exchanger to clean the tube and enhance the heat transfer. The rotors containing baldes with different hands have different effects to clean the tube automatically and enhance heat transfer. This thesis analyses the same-rotor, in-cross-rotor and ex-cross-rotor. Detailed contents of work are as follows:The same-rotor, in-cross-rotor and ex-cross-rotor are designed with the three-dimensional drawing software. Self-cleaning fouling experiments with same-rotor and in-cross-rotor are done, and the results are obtained from long time experiments and indicate that the performance of in-cross-rotor is better than the same-rotor's. By the heat transfer experiments, it is validated that the effect of heat transfer enhancement of ex-cross-rotor is better than smooth's at the same water flow, and it is significant to find that the heat transfer enhancement performance of in-cross-rotor is superior to same-rotor's, and that if rotor's diameter is larger, the heat transfer enhancement performance is superior. In order to combine the experiment research with engineering application, the efficiency of heat transfer in the condenser fixed with same-rotors is improved, therefore the goal of saving energy and reducing emission is reached. At last, the rotor structures are discussed further on the basis of rotor application effect and engineering requirement.