2) As shown in the figure, the inner layer of a sphere with two layers is...

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2) As shown in the figure, the inner layer of a sphere with two layers is made from material a. The outer layer of this sphere is made from three different materials (b, c and, d materials). These materials have peripheral angles of =2=2=7. Considering steady-state, one-dimensional (in r direction) heat transfer without heat generation and constant thermophysical properties conditions, a) By drawing thermal resistance circuit, find the total thermal resistance (RT,) in this heat transfer problem. b) Find the heat transfer rate (q7) through this composite sphere to the fluid using the total thermal resistance. c) Find the overall heat transfer coefficient according to the outer surface of this composite sphere (K.) using the total thermal resistance. d) Find the outer surface temperature of this composite sphere (T3). e) Find the critical insulation radius (rer). [kins. = 0.2 W/(m.K)]. f) Find the insulation thickness (fins.) that is expected to apply to the outer surface of the sphere for reducing the heat transfer rate up to 30%. d r3 " a b T- T=225 C T&c=25 C r = 20 mm r2 = 30 mm r3 = 40 mm h = 10 W/(m-K) ka 100 W/(mK) kb=200 W/(mK) ke 300 W/(m.K) ka 400 W/(m.K) T3 T, h 2) As shown in the figure, the inner layer of a sphere with two layers is made from material a. The outer layer of this sphere is made from three different materials (b, c and, d materials). These materials have peripheral angles of =2=2=7. Considering steady-state, one-dimensional (in r direction) heat transfer without heat generation and constant thermophysical properties conditions, a) By drawing thermal resistance circuit, find the total thermal resistance (RT,) in this heat transfer problem. b) Find the heat transfer rate (q7) through this composite sphere to the fluid using the total thermal resistance. c) Find the overall heat transfer coefficient according to the outer surface of this composite sphere (K.) using the total thermal resistance. d) Find the outer surface temperature of this composite sphere (T3). e) Find the critical insulation radius (rer). [kins. = 0.2 W/(m.K)]. f) Find the insulation thickness (fins.) that is expected to apply to the outer surface of the sphere for reducing the heat transfer rate up to 30%. d r3 " a b T- T=225 C T&c=25 C r = 20 mm r2 = 30 mm r3 = 40 mm h = 10 W/(m-K) ka 100 W/(mK) kb=200 W/(mK) ke 300 W/(m.K) ka 400 W/(m.K) T3 T, h

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The problem describes heat transfer in a composite sphere composed of three different materials a b c and an outer convective layer with given thermal ... View the full answer