Slowly-closing valve behaviour during steam machine accelerated start-up

Abstract

The paper discusses the state of stress in a slowly-closing valve during accelerated start-up of a steam turbine. The valve is one of the first components affected by high temperature gradients and is a key element on which the power, efficiency and safety of the steam system depend. The authors calibrated the valve model based on experimental data and then performed extended Thermal-FSI analyses relative to experiment. The issue is important as determining the possibility of accelerating the start-up of a steam turbine while not exceeding the strength limit in the design of the steam valve. The shorter the startup time, the more environmental and economic benefits. The most important results of the work include the possibility to reduce the start-up time of a steam machine without excessive strain on the valve structural components and not to exceed the stress limits. The important news for the industry is that there is no need to change the valves construction in terms of accelerated start-up of the steam engine. The results of the work confirm the belief that fast start-up of a steam turbine is possible without large capital expenditures for design changes in the components of the steam system.