Design And Simulation Of Superheated Steam Mass Flow Measurement Device

Accurate measurement of steam flow is very important to save energy and improve economical benefit. Business puts the measurement of superheated steam to the critical position. Thermal power plants which account for a major position in the China power supply enterprises, have strict requirement on accuracy and content in the measurement of main steam flow, so it is quite necessary to study mass flow measurement of superheated steam. This paper studies on the mass flow measurement of superheated steam in thermal power unit. Because that generating units of high parameter and large capacity are put into production continuously, original ways of flow measurement face the problems of large pressure loss, low accuracy and short life etc. At the same time, the application of the physical formula faces the problem of low precision. In this context, we must adopt a new design idea and design a new quality flow device for measurement of mass flow.This design uses the fluidic flowmeter for main steam mass flow measurement. First, the methods of main steam flow measurement in the thermal power unit are studied. The structure of the fluidic flowmeter as well as its principle is also researched. Second, geometry size and shape of fluidic flowmeter are designed. This flowmeter is established as a two-dimensional model by GAMBIT software and a new pressure measuring point is set up based on the model. Fluid under different mass flows and constant pressure is simulated by calculation software FLUENT, the results show that the effect of the new pressure measuring point is good, the main steam mass flow and oscillation frequency of fluidic flowmeter have good linearity, so that the improved fluidic flowmeter can be used for main steam mass flow measurement. At the end, fluidic flowmeters with different sizes are simulated to explore the effect of fluidic flowmeter’s entrance size on oscillation frequency of fluid and pressure loss. A better fluidic flowmeter used for large unit mass flow measurement is designed.