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AUTHOR(S):

L. Varshney, Rameshwar Kumar Singh

 

TITLE

Heat Transfer and Pressure Drop Characteristics in a packed bed Solar Air Heater

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ABSTRACT

In the present work an experimental setup has been designed and fabricated for the experimental investigations on a packed bed solar air heater under simulated conditions. Wire mesh screen matrices with different geometrical parameters have been used as packing element in the flow duct. Data pertaining to heat transfer and friction factor characteristics were collected for air flow rate ranging from 0.0101 to 0.0250 kg/s.m2 for five sets of matrices with varying geometrical parameters. The thermal efficiency of packed bed solar air heater was compared with that of a conventional solar heater. Enhancement in the thermal efficiency, of the order of 41.15 to 82.40% was obtained as compared to conventional smooth solar collector under similar operating conditions investigated in the present work. The effect of geometrical parameters (wire diameter, pitch, porosity and number of layers) of matrices on the heat transfer coefficient and pressure drop, which affect the thermal efficiency of the collector, has been discussed in detail.

 

KEYWORDS

Solar collector, packed bed, geometrical parameters, wire mesh, air heater, heat transfer

 

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Cite this paper

L. Varshney, Rameshwar Kumar Singh. (2017) Heat Transfer and Pressure Drop Characteristics in a packed bed Solar Air Heater. International Journal of Mechanical Engineering, 2, 111-118

 

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