Chilled water enters a thin-shelled 5cm diameter, 150m long pipe at 7 degrees C at a rate of .98kg/s and leaves at 8 degrees C.The pipe is exposed to ambient air at 30 degrees C with a heat transfer coefficient of 9W/m2 C. If the pipe is to be insulated with glass wool insulation (k=.05 W/m C) in order to decrease the temperature rise of water to .25 degrees C, determine the required thickness of the insulation.
Please Help!