The effects of fin height, fin-tube contact thickness and louver length on the performance of a compact fin-and-tube heat exchanger

The effects of fin height, fin-tube contact thickness and louver length on the performance of a compact fin-and-tube heat exchanger

Kourosh JavaherdehAhmad Vaisi Rouhollah Moosavi 

Department of Mechanical Engineering, University of Guilan, Rasht 4199613776, Iran

Department of Mechanical Engineering, Yasouj University, Yasouj 7591874934, Iran

Corresponding Author Email: 
Javaherdeh@guilan.ac.ir
Page: 
825-834
|
DOI: 
https://doi.org/10.18280/ijht.360307
Received: 
21 April 2017
| |
Accepted: 
9 March 2018
| | Citation

OPEN ACCESS

Abstract: 

In this paper, the effects of fin height, louver length and fin-tube contact thickness on the amount of heat transfer and pressure drop in a compact louvered fin-and-tube heat exchanger were studied experimentally and numerically using the $\varepsilon$ — NTU method. The effects of fin-tube contact thickness (with the variations of this thickness being more than or less than fin thickness variation) and fin height and also the relationship between Louvre length and fin height were examined. To validate the modeling, first, the numerical model was compared with an experimental prototype, and a good agreement was observed between the experimental and numerical results. The modeling results indicate that the increase in the fin-tube contact thickness, until the contact thickness becomes equal to fin thickness, leads to the improvement of heat exchanger performance; but beyond that, it is ineffective. Also, heat exchanger performance improves with the increase of louver length at a fixed fin height. According to the results, the minimum Louvre length should be 1.0 mm less than the fin height. An analytical equation relating Louvre length to fin height has been obtained, which agrees with model results by up to 98%.

Keywords: 

compact heat exchanger, louvered fins, experimental, numerical, pressure drop, Nusselt number

1. Introduction
2. Mathematical Analysis
3. Experimental Setup
4. Results and Discussion
5. Conclusions
Acknowledgements

The authors would like to express gratitude to Jalal Manouchehrian and Ebrahim Kahinpour, two senior Managers of Radiator Iran Company, for the close cooperation and supporting this work.

Nomenclature
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