Some automobile manufacturers are currently working on a ceramic engine block that could operate without a cooling system. Idealize such an engine as a rectangular solid, 45 cm by 30 cm by 30 cm. Suppose that under maximum power output the engine consumes 5.7 liters of fuel per hour, the heat released by the fuel is 9.29 kWh per liter and the net engine efficiency (useful work output divided by the total heat input) is 0.33. If the engine block is alumina with a gray-body emissivity of 0.9, the engine compartment operates at 150?C, and the convective heat transfer coefficient is 30W/(m2 K), determine the average surface temperature of the engine block. Comment on the practicality of the concept.GIVENCeramic engine block, 0.45m by 0.3m by 0.3mEngine gas consumption is 5.7 1/hHeat released is 9.29 (kWh)/1Net engine efficiency (η) = 0.33Emissivity (ε) = 0.9Convective heat transfer coefficient (hc) = 30 W/(m2 K)Engine compartment temperature (Tc) = 150?C = 423 KASSUMPTIONSHeat transfer has reached steady stateThe engine compartment behaves as a blackbodyenclosure

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Englne Block 0.3 m 0.3 m 0.45