A 3.6-cm inside diameter stainless steel pipe is being used to convey a liquid food. The inside convective heat-transfer coefficient is 10 J/s.m2.oC. The pipe is 0.5 cm thick and has a thermal conductivity of 43 J/s.m.oC. The pipe is insulated by an insulating material (thickness 2.5 cm) which has a thermal conductivity of 0.01 J/m.s.oC. The outside convective heat-transfer coefficient is 100 J/m2.oC.
a) Calculate the overall heat transfer coefficient for this system.
b) What is the heat loss from a pipe of 1-m length if the food temperature inside the pipe is 80oC whereas the outside ambient temperature is 20oC.