Numerical Analysis on the Influence of a Novel Semi-D shaped Turbulator on Heat Transfer Enhancement of Solar Air Heater

Heat transfer enhancement in Solar Air Heater (SAH) has been investigated by implementing rough surfaces in the absorber plate. We use paraffin wax is used as Phase Change Material (PCM) integrated with SAH as a Thermal Energy Storage (TES) system. A maximum convective heat transfer is attained during the daytime and retained as latent heat (LH) to discharge heat during OFF radiation. In this investigation, two types of absorber plates were employed such as flat & polygonal-shaped ribs at the test section. Further to investigate the heat transfer enhancement, the research was conducted with and without PCM. The study was carried out at the mass flow rates of 0.062 kg/s, 0.028 kg/s, and 0.01 kg/s to ascertain the enhancement of thermal efficiency and heat discharge duration. The temperatures of absorber plate Tp, ambient Tamb, outlet Tout and PCM along with Solar Intensity I (W/m-2) were taken as the main parameters. The research reveals that the absorber plate with polygonal ribs tested with PCM yields a higher temperature of 77?C with a mass flow rate of 0.062 kg/s during peak radiation. And discharged heat energy from PCM to absorber plate for 3.5 hours with a maximum temperature of 7.1?C.

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Fluid flow and heat transfer analysis for heat transfer enhancement in three sided artificially roughened solar air heater

Solar Energy ◽

10.1016/j.solener.2014.03.027 ◽

2014 ◽

Vol 105 ◽

pp. 27-35 ◽

Cited By ~ 24

Author(s):

B.N. Prasad ◽

Arun K. Behura ◽

L. Prasad

Keyword(s):

Heat Transfer ◽

Fluid Flow ◽

Heat Transfer Enhancement ◽

Heat Transfer Analysis ◽

Solar Air Heater ◽

Transfer Enhancement ◽

Air Heater ◽

Flow And Heat Transfer

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Use of artificial roughness to enhance heat transfer in solar air heaters – a review

Journal of Energy in Southern Africa ◽

10.17159/2413-3051/2010/v21i1a3248 ◽

2010 ◽

Vol 21 (1) ◽

pp. 35-51 ◽

Cited By ~ 2

Author(s):

Thakur Sanjay Kumar ◽

N.S. Thakur ◽

Anoop Kumar ◽

Vijay Mittal

Keyword(s):

Heat Transfer ◽

Heat Transfer Enhancement ◽

Heat Transfer Rate ◽

Transfer Rate ◽

Hydraulic Performance ◽

Solar Air Heater ◽

Artificial Roughness ◽

Transfer Enhancement ◽

Air Heater ◽

Roughness Elements

Improvement in the thermo hydraulic performance of a solar air heater can be done by enhancing the heat transfer. In general, heat transfer enhancement techniques are divided into two groups: active and passive techniques. Providing an artificial roughness on a heat transferring surface is an effective passive heat transfer technique to enhance the rate of heat transfer to fluid flow. In this paper, reviews of various artificial roughness elements used as passive heat transfer techniques, in order to improve thermo hydraulic performance of a solar air heater, is done. The objective of this paper is to review various studies, in which different artificial roughness elements are used to enhance the heat transfer rate with little penalty of friction. Correlations developed by various researchers with the help of experimental results for heat transfer and friction factor for solar air heater ducts by taking different roughened surfaces geometries are given in tabular form. These correlations are used to predict the thermo hydraulic performance of solar air heaters having roughened ducts. The objective is to provide a detailed review on heat transfer enhancement by using an artificial roughness technique. This paper will be very helpful for the researchers who are researching new artificial roughness for solar air heater ducts to enhance the heat transfer rate and comparing with artificial roughness already studied by various researchers.

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