Review Paper on Green’s Function- A Mathematical Approach for Investigation of Thermal Stresses in Steam Turbine Rotor

Abstract

In online systems, a numerical technique based on Green’s function for estimating and analyzing thermal stresses subjected to transient conditions proved to be effective. The need for utility power plants to have great operating flexibility necessitates the use of online systems for controlling and monitoring damage to important components, such as steam turbine rotors. Different data and mathematical models are used in such systems to calculate thermal stresses and manage them continuously. Thermal fatigue is becoming more of a worry in power plant workers as the trend toward “two-shifting” operating methods grows. Thermal power plants are anticipated to be a form of energy mix for the near future when they’re under pressure from society to produce in a more efficient and flexible manner.For transient thermal stress problems, Green’s function approach offers a flexible approach for assessing benchmark elastic answers. Green’s functions (deduced using finite element unit temperature phase answers) are frequently believed to be independent of temperature in order to ease integration. During startup, the turbine shafts of coal power plants are subjected to significant stresses caused by high pressures and temperatures. Thermal gradients approach the design threshold at the very same time that steam temperatures via components quickly transition from minimum to maximum temperature, reducing the rotor’s useful lifetime. Thermal property assessments predicated on relatively stable heating are implicit procedures wherein the temperature-dependent properties and characteristics are determined by comparing the experimental results with heat-transfer concept.