Steam enters a turbine operating at steady state at 1.25 mpa, 200°c and exits at 40°c with a quality of 83%. stray heat transfer and kinetic and potential energy effects are negligible.

Awall of 0.5m thickness is to be constructed from a material which has average thermal conductivity of 1.4 w/mk. the wall is to be insulated with a material having an average thermal conductivity of 0.35 w/mk so that heat loss per square meter shall not exceed 1450 w. assume inner wall surface temperature of 1200°c and outer surface temperature of the insulation to be 15°c. calculate the thickness of insulation required.