Theoretical Analysis of Continuous Heat Extraction from Absorber of Solar Still for Improving the Productivity

This paper communicates the theoretical analysis of continuous waste heat extraction from the other side of absorber plate. For theoretical analysis two conditions are determined one is the mass of water in the absorber and another one is mass flow rate of water around the absorber plate. Results indicated that the water temperature is reached maximum at 10 kg of mass and 5 kg/hr mass flow of water and the heat extracted from the absorber is higher at optimum mass flow of 5 kg/hr. Also, the higher temperature difference between the water and the collector cover is found during the off-shine period. The maximum achievable hourly productivity of 0.9 and 0.5 kg is found for the solar still with and without circulation respectively. The yield from present model with continuous heat extraction is increased from 3 to 5.5 kg/m2. As the approached method is more new to the society it may be determined by Agouz- Nagarajan- Sathyamurthy (ANS) model

Investigation on the Optical Design and Performance of a Single-Axis-Tracking Solar Parabolic trough Collector with a Secondary Reflector

The design of solar concentrating collectors for the effective utilization of solar energy is a challenging condition due to tracking errors leading to different divergences of the solar incidence angle. To enhance the optical performance of solar parabolic trough collectors (SPTC) under a diverged solar incidence angle, an additional compound parabolic concentrator (CPC) is introduced as a secondary reflector. SPTC with CPC is designed and modeled for a single axis-tracking concentrating collector based on the local ambient conditions. In this work, the optical performance of the novel SPTC system with and without a secondary reflector is investigated using MATLAB and TRACEPRO software simulations for various tracking errors. The significance parameters such as the solar incidence angle, aperture length, receiver tube diameter, rim angle, concentration ratio, solar radiation, and absorbed flux are analyzed. The simulation results show that the rate of the absorbed flux on the receiver tube is significantly improved by providing the secondary reflector, which enhances the optical efficiency of the collector. It is found that the optical efficiency of the SPTC with a secondary reflector is 20% higher than the conventional collector system for a solar incidence angle of 2°. This work can effectively direct the choice of optimal secondary reflectors for SPTC under different design and operating conditions