Question 6 A phase change fluid at 74°C is pumped through 7 m of a multi-layered pipe, which is exposed to an external fluid current at 22°C. The innermost layer is made of steel (thermal conductivity 13 W/m/K), with inner and outer radii 40 mm and 52 mm, respectively. The second layer is made of insulating material (thermal conductivity 0.6 W/m/K), with outer radius equal to 70 mm. The convective heat transfer coefficients associated to the internal and external fluids are respectively 1,166 W/m2/K and 150 W/m2/K. Calculate the heat transfer (absolute value) through the pipe thickness in kW to 1 decimal place. Note: use pi=3.1415