A long steel bar (20 mm diameter) at 455°C is placed horizontally in a water bath...
A long steel bar (20 mm diameter) at 455°C is placed horizontally in a water bath at 100°C under atmospheric pressure. (a) Estimate the initial heat transfer rate per unit length of the bar to the water when it is initially placed in water. You may assume emissivity of the steel bar to be 1. (b) What type of heat transfer mechanism is present when the bar has cooled to 110°C.
Homework Answers
ANSWER
Given data
diameter = 20 mm
Initial temperature of T i = 455degC
Temperature of water bath t = 100degC
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A long steel bar (20 mm diameter) at 455°C is placed
horizontally in a water bath...
A long steel bar (20 mm diameter) at 455°C is placed horizontally in a water bath...
A long steel bar (20 mm diameter) at 455°C is placed horizontally in a water bath at 100°C under atmospheric pressure. (a) Estimate the initial heat transfer rate per unit length of the bar to the water when it is initially placed in water. You may assume emissivity of the steel bar to be 1. (b) What type of heat transfer mechanism is present when the bar has cooled to 110°C.
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P.1.9. A bar of mild steel has a diameter of 75 mm and is placed inside a hollow aluminum cylinder of internal diameter 75 mm and external diameter 100 mm; both bar and cylinder are the same length. The resulting composite bar is subjected to an axial compressive load of 1000 KN. If the bar and cylinder contract by the same amount, calculate the stress in each. The temperature of the compressed composite bar is then reduced by 150°C but...
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