Concentrating solar collectors systems and especially the mini Parabolic solar reflecting systems have been one of the main research topics due to their ability for integration into the building structure. In the present work the mini parabolic collector was considered in the East West orientation with such a slope so that the suns vector impinging normal to the parabola during the day. The beh...

one of the effective methods to improve the thermal efficiency of solar collectors is using nanofluids as the coolant. the present study experimentally investigated the effect of sio2/water nanofluid with 1% mass fraction on the performance of a symmetric collector, i.e. conical solar collector. the conical solar collector with 1 m2 area and normal to the earth was tested in ahvaz, a city in th...

In the present work, a prototype of a new type of solar collectors, which called Direct Absorption Solar Collector, was built and its thermal performance is experimentally compared with conventional flat plate solar collector under transient and steady state conditions. Different volume fractions of multi wall carbon nanotubes in water and ethylene glycol mixture (70%:30% in volume) were used a...

This article presents the latest experimental results of the European DISS (DIrect Solar Steam) project. The experiments are subdivided into steady state and transient tests. The goal of the steady state tests is the investigation of the thermohydraulic phenomena of the occurring two phase flow, whereas the transient tests are needed for the controller design. The experimental results are compa...

This paper explores the benefits and drawbacks of using carbon dioxide in solar thermal systems at medium and high operating temperatures. For medium temperatures, application of CO2 in non-imaging-optics based compound parabolic concentrators (CPC) combined with evacuated-tube collectors is studied. These collectors have been shown to obtain efficiencies higher than 40% operating at around 200...

In the present work, a prototype of a new type of solar collectors, which called Direct Absorption Solar Collector, was built and its thermal performance is experimentally compared with conventional flat plate solar collector under transient and steady state conditions. Different volume fractions of multi wall carbon nanotubes in water and ethylene glycol mixture (70%:30% in volume) were used a...

A mathematical model for computing the thermal performance of an air heater with a truncated compound parabolic concentrator having a flat one-sided absorber is presented. A computer code that employs an iterative solution procedure is constructed to solve the governing energy equations and to estimate the performance parameters of the collector. The effects of the air mass flow rate, the wind ...

Recent interest in small-scale solar thermal combined heat and power (CHP) power systems has coincided with demand growth for distributed electricity supplies in areas poorly served by centralized power stations. One potential technical approach to meeting this demand is the parabolic trough solar thermal collector coupled with an organic Rankine cycle (ORC) heat engine. The paper describes the...