A thermally-insulated subsea pipeline is used to transport oil at 140 C and with a flowrate...

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A thermally-insulated subsea pipeline is used to transport oil at 140 C and with a flowrate of 1130 m/hr. The pipe is made of AISI 1010 carbon steel, has OD = 25 cm, ID = 20 cm, and it is insulated with a 1 cm-thick layer of fiberglass (k = 0.12 W/mK). The pipeline has a sand detector that can be approximated as a solid cylinder of 3 cm diameter attached to the OD of the pipe, and protruding 14 cm outside of the insulation OD. The sand detector is made of 2024-T6 aluminum. If the surrounding seawater is at 5 C and the sea current velocity is 0.5 m/s, in a direction perpendicular to the axes of the pipe and the sand detector, determine: a) The temperatures at the OD of the pipe and at the OD of the insulation. b) Assuming the sand detector is a fin with an insulated tip, and that temperature at its base is the same as the OD of the pipe, determine the heat loss through the sand detector. Hints: For the oil, use engine oil properties from table A-13 Assume fully developed flow in the pipe For seawater, use saturated water properties from table A-9 = 3cm 14 cm = 25 cm A thermally-insulated subsea pipeline is used to transport oil at 140 C and with a flowrate of 1130 m/hr. The pipe is made of AISI 1010 carbon steel, has OD = 25 cm, ID = 20 cm, and it is insulated with a 1 cm-thick layer of fiberglass (k = 0.12 W/mK). The pipeline has a sand detector that can be approximated as a solid cylinder of 3 cm diameter attached to the OD of the pipe, and protruding 14 cm outside of the insulation OD. The sand detector is made of 2024-T6 aluminum. If the surrounding seawater is at 5 C and the sea current velocity is 0.5 m/s, in a direction perpendicular to the axes of the pipe and the sand detector, determine: a) The temperatures at the OD of the pipe and at the OD of the insulation. b) Assuming the sand detector is a fin with an insulated tip, and that temperature at its base is the same as the OD of the pipe, determine the heat loss through the sand detector. Hints: For the oil, use engine oil properties from table A-13 Assume fully developed flow in the pipe For seawater, use saturated water properties from table A-9 = 3cm 14 cm = 25 cm