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Plate heat exchangers are new-type compact heat exchangers with high heat transfer efficiency widely used in heating, food, medicine, shipbuilding and petrochemical industries. However, only the laboratory testing can accurately obtain the real heat transfer and flow resistance performance of plate heat exchanger. In this paper, the basic principles of modified Wilson plot method and equal velocity method are firstly introduced. Then the testing system including flow chart and testing instruments are discussed. Finally, contrast experiments using the different two methods are conducted. The results showed that for plate heat exchangers with equal channel, the equal velocity method and modified Wilson plot method can both be used to test the convective heat transfer performance of plate heat exchanger. The equal velocity method is recommended because the deformation of plate is relatively smaller.

Because of its structural characteristics, the serpentine high-pressure heater has thinner tubesheet compared with the traditional U-tube high-pressure heater, which solves the bottleneck of tubesheet manufacturing and becomes an important auxiliary machine for millions of secondary reheating units in the future. In this paper, the typical working conditions are selected, and the bending design methods of domestic and foreign serpentine tubes are adopted respectively. The results show that compared with Chinese standards, the bending can be thinned. Subsequent tests and finite element simulations verify the reliability of foreign methods and explore the optimization design methods of domestic serpentine tubes.

It could be seen that the ultra supercritical reheating is a high-end technology in the field of power equipment manufacturing, which represents the strength and design level of national major equipment manufacturing industry. Based on the development of key components technology of millions of secondary reheat units, solving the design and manufacturing problems of serpentine high-pressure heater, optimizing the heat exchange efficiency of serpentine high-pressure heater, and improving the operation reliability, will help to promote the development process of China’s high-end power equipment, and provide important technical support for the quality supervision and management of serpentine high-pressure heater.

Steel-water gravity heat pipe has been widely used in industry because of its low cost and wide applicable temperature range. Steel-water incompatibility can produce hydrogen as a non-condensable gas, seriously weakening the heat transfer capacity. In this paper, the start-up and isothermal performance of thermosyphon with noncondensable gas were studied by experimental methods, and the effect of gas ratio on the start-up and isothermal performance was quantitatively analysed. The results show that the larger gas ratio will increase the start-up time and the working temperature. The wall temperature of evaporation section is higher than that of adiabatic and condensation section. The distributions of wall temperature in the evaporator and adiabatic sections are uniform. The non-isothermal phenomenon only occurs in the condenser section.

This paper systematically discusses the significance of pressure vessel inspection, defines the main body of annual inspection of pressure vessel, and puts forward the matters needing attention in the process of annual inspection according to the existing annual inspection situation, so as to provide a certain reference for the smooth development of annual inspection of pressure vessels.