Q6/ A spherical tank, 1 m in diameter, is maintained at a temperature of 120 C and exposed to a convection environment. With h-25W/m2.•C and To =15 C, what thickness of urethane foam should be added to ensure that the outer temperature of the insulation does not exceed 40 C? What percentage reduction in heat loss results from installing this insulation?

Q6/ A spherical tank, 1 m in diameter, is maintained at a temperature of 120 C and exposed to a convection environment. With h-25W/m2.•C and To =15 C, what thickness of urethane foam should be added to ensure that the outer temperature of the insulation does not exceed 40 C? What percentage reduction in heat loss results from installing this insulation?