1. A brass rod 100 mm long and 5 mm in diameter extends horizontally from a...

 

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1. A brass rod 100 mm long and 5 mm in diameter extends horizontally from a casting at 200°C. The rod is in an air environment with T = 20 °C and h = 30W/m².K. a) What is the temperature of the rod 25, 50 and 100 mm from the casting? Assume that the fin tip is adiabatic. In addition to the temperatures along the fin, also determine the heat flow through the rod, the fin effectiveness, and the fin efficiency. b) Suppose that this single brass rod is attached to a casting surface that is 10 cm by 10 cm square. What is the rate of heat flow to the air from the exposed area of the casting surface (qunfin)? What is the total heat flow from the surface and the rod to the air (qtotal)? c) Compute the volume of the brass rod. Suppose we take this volume of brass and fabricate an array of 100 rectangular fins that are 0.5 mm thick and 10 cm wide (see Figure 3.21a). Using this information, determine the fin pitch S and fin length L. d) Based on the array dimensions from part (c), determine the rate of heat flow rate from the casting to the air through the fin array. 1. A brass rod 100 mm long and 5 mm in diameter extends horizontally from a casting at 200°C. The rod is in an air environment with T = 20 °C and h = 30W/m².K. a) What is the temperature of the rod 25, 50 and 100 mm from the casting? Assume that the fin tip is adiabatic. In addition to the temperatures along the fin, also determine the heat flow through the rod, the fin effectiveness, and the fin efficiency. b) Suppose that this single brass rod is attached to a casting surface that is 10 cm by 10 cm square. What is the rate of heat flow to the air from the exposed area of the casting surface (qunfin)? What is the total heat flow from the surface and the rod to the air (qtotal)? c) Compute the volume of the brass rod. Suppose we take this volume of brass and fabricate an array of 100 rectangular fins that are 0.5 mm thick and 10 cm wide (see Figure 3.21a). Using this information, determine the fin pitch S and fin length L. d) Based on the array dimensions from part (c), determine the rate of heat flow rate from the casting to the air through the fin array.