5. A steam pipe (kpipe = 45 W/m K) having 70 mm inner diameter and 85...

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5. A steam pipe (kpipe = 45 W/m K) having 70 mm inner diameter and 85 mm outer diameter is covered with a 35 mm thick layer of insulation (kins = 0.15 W/m K). In order to protect the insulation material from the humid environment, the pipe is further covered by a 25 mm thick layer of ceramics material (keeramics=0.075 W/m K). The heat transfer coefficient inside and outside of the pipe are 220 W/m² K and 6.5 W/m².K, respectively. Steam temperature is maintained at 350°C whereas the average outside air temperature is 30°C. Under steady state condition, the temperature at the outer surface of the ceramic layer is 77.76°C. Calculate the heat flux crosses the inner surface and outer surface of the pipe, respectively. 5. A steam pipe (kpipe = 45 W/m K) having 70 mm inner diameter and 85 mm outer diameter is covered with a 35 mm thick layer of insulation (kins = 0.15 W/m K). In order to protect the insulation material from the humid environment, the pipe is further covered by a 25 mm thick layer of ceramics material (keeramics=0.075 W/m K). The heat transfer coefficient inside and outside of the pipe are 220 W/m² K and 6.5 W/m².K, respectively. Steam temperature is maintained at 350°C whereas the average outside air temperature is 30°C. Under steady state condition, the temperature at the outer surface of the ceramic layer is 77.76°C. Calculate the heat flux crosses the inner surface and outer surface of the pipe, respectively.