A manned spacecraft capsule has a shape of a cylinder 2.5 m in diameter and 9 m long. The air inside the capsule is maintained at 20°C, and the convection heat transfer coefficient on the interior surface is 17 W/m^2K. Between the outer skin and the inner surface is a 15-cm layer of glass-wool insulation having a thermal conductivity of 0.017 W/m. K. If the emissivity of the skin is 0.05 and there is no aerodynamic heating or irradiation from astronomical bodies. Calculate the total heat transfer rate into space at 0 K.

The y form of iron is known as: a) ferrite b) cementite c) perlite d) austenite

Steel is coated with a thin layer of ceramic to protect against corrosion. what do you expect to happen to the coating when the temperature of the steel is increased significantly? explain.

Air is to be cooled in the evaporator section of a refrigerator by passing it over a bank of 0.8-cm-outer-diameter and 0.4-m-long tubes inside which the refrigerant is evaporating at -20°c. air approaches the tube bank in the normal direction at 0°c and 1 atm with a mean velocity of 4 m/s. the tubes are arranged in-line with longitudinal and transverse pitches of sl- st 1.5 cm. there are 30 rows in the flow direction with 15 tubes in each row. determine (a) the refrigeration capacity of this system and (b) pressure drop across the tube bank. evaluate the air properties at an assumed mean temperature of -5°c and 1 atm. is this a good assumption?