Heat Transfer Rate & Estimation in Air-Steam Flow System

AI Thread Summary
The discussion focuses on calculating the heat transfer rate in a system where air flows through a copper tube heated by condensing steam. Key tasks include determining the heat transfer rate at various air flow rates, calculating the overall heat transfer coefficient, and estimating the inside film heat transfer coefficient. The Dittus-Boelter equations are suggested for predicting the film heat transfer coefficient, which should then be compared with experimental results. Participants are encouraged to develop an energy balance for the system and explore heat exchanger theory for insights. The conversation emphasizes the importance of precise measurements and assumptions in the calculations.
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Thought this would be the most appropriate forum to ask for help

Air flows through a copper inside tube and is heated by saturated steam condensing on the outside of the tube.

1. Determine the rate of heat transfer to the air at 3 different flow rates of the air (rotameter readings 10, 20 and 30).
For each air flow rate:
2. Experimentally determine the overall heat transfer coefficient based on the outside area of the pipe.
3. Estimate the inside (air) film heat transfer coefficient assuming that the resistances of the copper wall and steam film are small compared to the resistance of the air film.
4. Predict the film heat transfer coefficient using the Dittus-Boelter equations.
5. Compare the film heat transfer coefficients from the experiments with those calculated from the Dittus-Boelter equation. Comment on the comparison.
6. Estimate the steam consumption, stating assumptions.

The schematic is attached.

The dimensions of central copper tube are:
Length: L = 300 mm
Inside diameter: di = 4.5 mm
Outside diameter: do = 6.3 mm

Just wondering what the best way to approach this is, and how to answer all the questions, what measurements to make etc?

Any links or straight out advice?

Thanks very much
 

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Develop the energy balance for the system. What comes in is what goes out in some form or another. Ask yourself what those different ways energy can be manifested. I would suggest to look at simple heat exchanger theory for hints since that's what this is.
 
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