Numerical Analysis of Heat Transfer of a Brazed Plate Heat Exchanger

Abstract

In this paper, we investigated the heat transfer characteristics of a brazed plate heat exchanger by using Computational Fluid Dynamics (CFD). Heat exchangers were generally analyzed considering both rating and sizing parameters. We just examined the rating parameters such as flow direction, mass flow rate, and the inlet temperature value of hot water on the thermal performance of a brazed plate heat exchanger, numerically. We also employed experiments for getting comparative results and each experiment was performed under the same conditions selected in the numerical simulations. Theoretical calculations were achieved by using the Logarithmic Mean Temperature Difference (LMTD) method for a single-phase flow and the thermal efficiency of the heat exchanger was evaluated for different conditions. The maximum total heat transfer rate was calculated about 3.1 kW for experimental study whereas this value was lower than 3 kW for numerical study in counter flow conditions. Another important result was that the effectiveness values of the heat exchanger were calculated higher under counter flow conditions as expected. The numerical results were in good agreement with the experimental data used in the study.

Keywords

• Brazed plate heat exchanger
• counter-flow
• LMTD method
• thermal performance
• CFD

Lehimli Plakalı Isı Değiştiricisi Isı Transferinin Sayısal Analizi

Abstract

In this paper, the heat transfer characteristics of a brazed plate heat exchanger were investigated by using Computational Fluid Dynamics (CFD) method. Due to its compact structure, the plate type heat exchangers are used in many engineering applications such as manufacturing, automotive, etc. Heat exchangers are generally analyzed considering both rating and sizing parameters. We only examined the rating parameters such as flow direction, mass flow rate, and the inlet temperature value of hot water on the thermal performance of a brazed plate heat exchanger, numerically. We also conducted experiments under the same conditions for getting comparative results with the numerical simulations. Theoretical calculations were achieved by using the Logarithmic Mean Temperature Difference (LMTD) method for a single-phase flow and the thermal efficiency of the heat exchanger was evaluated for different conditions. The maximum total heat transfer rate was calculated about 3.1 kW for experimental study whereas this value was about 3 kW for numerical study under the counter flow conditions. Considering the increase in percentage for the total heat transfer rate, the mass flow rate had more effects than the other rating parameters such as flow direction and hot water inlet temperature values. Another important result was that the effectiveness values of the heat exchanger were calculated higher under the counter flow conditions. The numerical results were in good agreement with the experimental data used in the study.

Keywords

• Lehimli plakalı ısı değiştirici
• ters yönlü akış
• LMTD metodu
• ısıl performans
• HAD

References

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