Heat and Mass Transfer Coefficients Under Frost Conditions In A Finned-Tube Evaporator
نویسندگان
چکیده
The objectives of this study are to provide experimental data and a correlation that can be used in the optimal design of an evaporator under frost conditions. In the present study, we tested both a single stage and a two-stage evaporator with a variation of operating parameters and fin geometry under frost conditions. The effects of tube space and fin alignment on the heat transfer performance were also investigated. The airside heat and mass transfer coefficients were calculated from the measured data. Besides, two correlations for frost thickness and airflow ratio were developed as a function of dimensionless operating parameters and fin geometry.
منابع مشابه
Performance Evaluation Of Peripheral-Finned Tube Evaporators Under Frosting Conditions
The peripheral finned-tube (PFT) is a novel air-side geometry for compact heat exchangers. Previous studies (Pussoli et al., 2012) evaluated the thermal-hydraulic performance of the PFT geometry under dry conditions (i.e., no frost or condensate formation on the air side). The present study focuses on quantifying the thermal-hydraulic performance of the PFT geometry under frosting conditions. A...
متن کاملThe Influence of the Inlet Conditions on the Airside Heat Transfer Performance of Plain Finned Evaporator
A numerical study has been conducted to investigate the influence of fin pitch and relative humidity on the heat transfer performance of the fin-and-tube heat exchangers having plain fin geometry under dehumidifying conditions. The analysis is done using the ratio between the heat transfer coefficients in totally wet conditions and those in totally dry conditions using the appropriate correlati...
متن کاملEffect of Coil Geometry on Frost-Free Finned-Tube Evaporator Performance
This paper outlines a mathematical modelling approach to predict the steady-state behaviour of finned-coil evaporators. The model was built taking three domains into account: (i) refrigerant flow inside the coil; (ii) heat transfer through the walls; and (iii) air flow through the finned-coil array. The equations were obtained from the mass, momentum and energy conservation principles, mathemat...
متن کاملMinimization of Entransy Dissipations of a Finned Shell and Tube Heat Exchanger
Improving heat transfer and performance in a radial, finned, shell and tube heat exchanger is studied in this study. According to the second law of thermodynamics, the most irreversibilities of convective heat transfer processes are due to fluid friction and heat transfer via finite temperature difference. Entransy dissipations are due to the irreversibilities of convective heat transfer. There...
متن کاملThe Effects of Frost Formation in a Flat Plate Finned-Tube Heat Exchanger
An experimental study on the effects of various factors(fin spacing, fin arrangement, air temperature, air humidity, and air velocity) on the frost growth and thermal performance of a finned-tube heat exchanger has been conducted under the frosting condition. It is found that the thermal performance of a heat exchanger is closely related to the blockage ratio of air flow passage due to the fros...
متن کامل