m. ayazi

In this paper, the performance of a typical glass flat plate solar collector is evaluated experimentally by the test bench designed and constructed at Research Institute of Petroleum Industry (RIPI) in the city of Tehran. The results of five experimental tests including thermal performance evaluation, effective heat capacity, time constant, radiation angle correction factor and pressure drop are presented according to the Iranian National Standardization Organization (INSO) standard 7129. The results show that the highest thermal efficiency of the tested collector based on the gross surface area is 42.5% in ideal temperature conditions.In addition, its effective heat capacity is 42618 J/K and its time constant is obtained equal to106 seconds. Furthermore, its radiation angle correction factor is 0.85 for incident angle of 45o and the pressure drop of the tested collector is about 500 Pa for its working mass flow rate.

The purpose of this study is to analyze the two-phase flow in the recirculation region of a gas turbine combustion chamber by changing the effective geometrical parameters of its swirler. The natural and forced rotational flows caused by the geometry of the combustion chamber and flow field conditions have significant effects on combustion and air-fuel mixing. In this study, finite volume method and unstructural meshing are used in a commercial computational fluid dynamics software package in order to investigate the effects of rotational flow injection in combustion chamber and to carry out a parametric study. The obtained results show the volume of the recirculation zone in the primary area of the combustion chamber increases as the swirl number rises. This increases the turbulence intensity and improves air-fuel mixing.