Abstract:

In this study, increasing the heat transfer by the vertical positioning of the finned inner pipe heat exchanger which has different fin number has been discussed experimentally. The most important difference of the study from other studies is the vertical positioning of the heat exchanger. A testing set was installed to analyze the heat transfer in the vertically positioned heat exchanger. Heat transfers and pressure drop were analyzed at different inner pipes. The flow is turbulent for each tube with different fin number. Calculations were made both for finned inner pipe and annular spacing between inner pipe and outer pipe. All results were compared with each other to obtain the best results. According to the results, Reynolds number and Nusselt number were found and graphed. The values obtained from the experimental results are very close to the values derived from Petukhov's equation. In experiments, it was found that the best heat transfer was in pipe which has most fin number. In pipe which has 300 mm finned length, the heat transfer increased by 147.38% and also the pressure drop increased by 131.25% in comparison with straight tube. In finned inner tube heat exchangers, the amount of heat transfer is better than in straight tube. But with the effect of fins, pressure drops increase.

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