Ramalingam Senthil

Parametric Analysis of a Concentrated Solar Receiver with Scheffler Reflector

In this work, the effect of various parameters on the thermal performance and heat losses from the concentrated solar receiver is studied parametrically. A parabolic dish solar concentrating collector is used to heat the fluid in the receiver. The effect of the solar radiation, wind and ambient temperature on the receiver surface temperature is investigated for the thermal output. The wind velocity and ambient temperature are responsible for the heat losses from the receiver. The increase in wind velocity increases the forced convection heat losses and the increase in the ambient temperature reduces the thermal output of the system. The emissivity of the receiver coating plays a major role in the reduction of the radiation heat losses from the receiver. A reduction of emissivity from 0.9 to 0.2 decreases the radiation heat loss by 75%.

Optical and Thermal Performance Analysis of Solar Parabolic Concentrator

In this work, the effect of reflectivity of the reflector, absorptivity of the absorber, intercept factor and beam solar radiation in the thermal performance of a solar parabolic concentrator (SPC), are investigated. The optical energy input of a solar thermal collector is important, to achieve the maximum thermal performance. Polished aluminium, steel sheets and glass, with low iron content are used as the reflector materials. The absorber coating is black chrome and nickel for the improved heat absorption rate. The reflectivity of the reflector and the absorptivity of the absorber surface are the most influencing parameters, for the optical and thermal performance of SPC. An increase of 0.2 reflectivity or absorptivity, enhances the optical efficiency by 18%. The maximum temperature attainable over the absorber is 650 C, during the outdoor testing, without passing the fluid through the absorber.