This paper discusses the experimental and theoretical performance of a PARABOLIC TROUGH receiver using a nanofluid. The main aim of this work is to analyze the performance enhancement of the PARABOLIC TROUGH COLLECTOR system. The thermal model is developed using Engineering Equation Solver (EES). Experimental analysis was done with a water volume flow rate of 10 L/min and water inlet temperature range from 0 to 45 OC, also the volume fraction of Al2O3 nanoparticle varied from 1% to 5%. Experimental analysis conducted using Al2O3 nanoparticle mixed with water and used as heat transfer fluid in solar PARABOLIC TROUGH COLLECTOR. Results compared and observed that the model has very good acceptance with the experimental results. It is observed that the thermal efficiency of the COLLECTOR increased by 2 to 4% and receiver heat loss decreased from 0.82% to 2.72%. The receiver water temperature increased by 15% for the range of Al2O3 nanoparticle volume fraction. This work was carried out to investigate the use of renewable energy for water heating applications on rural farms in India. Small-sized PTC is simple in construction, economical, and does not require special skills to operate. However, considering the space requirement it would be better to investigate the method to improve the performance of PTC without changing the dimensions. One way to improve the performance is with the use of nanofluids. This work’s main finding is that the Nanoparticle with a volume fraction of 4 will improve the performance. It was observed that the temperature of the water was improved by 15% and the thermal efficiency was increased by 4%.

In the present work the effect of Cu-Water nanofluid, as heat transfer fluid, on the performance of a PARABOLIC solar COLLECTOR was studied numerically. The temperature field, thermal efficiency, mean-outlet temperatures have been evaluated and compared for the conventional PARABOLIC COLLECTORs and nanofluid based COLLECTORs. Further, the effect of various parameters such as fluid velocity, volume fraction of nanoparticles, concentration ratio and receiver length has been investigated. The results show that, by increasing the volume fraction of nanoparticles, the performance of the solar PARABOLIC COLLECTOR enhances.

In recent years, the use of renewable energy sources and investigation on renewable energy have significantly grown. In this research, PARABOLIC TROUGH and linear Fresnel COLLECTORs, which are widely used in the field of solar energy, have been investigated from the point of view of exergy. First, the energy balance equations for different components of the COLLECTOR were solved using numerical methods and the temperature distribution in each component of the COLLECTOR was obtained. Then the values of exergy destruction in each component of the system were calculated. The comparison of the results obtained in the present work with the results of the previous research showed a good agreement. The results showed that the exergy efficiency in the PARABOLIC TROUGH COLLECTOR is approximately 1.5 times that of the linear Fresnel reflector. Also, changes in exergy efficiency, exergy destruction of the whole COLLECTOR, output exergy cost and CO2 emission with increasing solar radiation intensity and fluid mass flow rate for both COLLECTORs have been compared and investigated.

In this study, the effect of wind speed on the energy and exergy efficiencies of the LS-2 PARABOLIC TROUGH solar COLLECTOR have been studied. The wind speed on the reflector and receiver has been considered between zero and 27 m/s. Three working fluids of Therminol VP-1, Syltherm 800 and Dowtherm A have been used. The inlet temperature of the working fluid and volumetric flow rate are assumed to be in the range of 300-650 K and 50-600 L/min, respectively. In order to solve the governing equations, a developed thermal model in the engineering equation solver has been used. The results showed that at the inlet fluid temperature of 650 K and volumetric flow rate of 50 L/min, if the wind speed increases to 27 m/s, the energy efficiency decreases using Therminol VP-1, Syltherm 800 and Dowtherm A are 0. 87%, 1. 16% and 0. 85%, respectively and the exergy efficiency decreases are 0. 88%, 1. 18% and 0. 86%, respectively. Also the results showed that the variations of energy and exergy efficiencies for wind speeds greater than 10 m/s are negligible. The results indicated that although wind speed increase has little effect on the energy and exergy efficiencies of the COLLECTOR, but the rate of these decreases are comparable with the rate of efficiency increases observed in previous studies using different efficiency enhancement strategies such as turbulators and nanofluids, so wind speed is important. The performance evaluation study revealed that using Therminol VP-1 and Dowtherm A are more suitable than Syltherm 800 to be used as working fluids in PARABOLIC TROUGH solar COLLECTORs

The objective of this study is to determine the energetic and exergetic enhancement of PARABOLIC TROUGH COLLECTOR with internal fins in the absorber. Carbon dioxide is the examined working fluid to investigate the performance of the system in high temperature levels. In the first part of this study, the impact of the mass flow rate on the COLLECTOR performance is analyzed and finally 0.20 kg/s is selected as the most appropriate mass flow rate exergetically.In the second part, the impact of internal fins on the system performance is investigated for operation with the optimum mass flow rate. More specifically, the absorber without fins is compared with three different fins with lengths 5, 10 and 15 mm. The final results prove that the higher fin length increases the thermal performance, while the optimum fin length exergetically is 10 mm with 45.95% exergetic efficiency when the inlet temperature is equal to 400oC. The impact of the pressure losses along the COLLECTOR is taken into account in the exergetic efficiency, which is the best index for evaluating solar COLLECTORs operating with gases. The analysis is performed with Solidworks Flow Simulation, a powerful tool which allows the simultaneous thermal and optical analysis.

Considering the daily increase of consumption and expense of nonrenewable energies such as naturalgas and electricity, application of clean and renewable energies such as solar thermal energy nowadays is highly considered. In this research, at first, simple steam Rankine cycle and two different configurations of combined steam and organic Rankine cycles with PARABOLIC TROUGH solar COLLECTOR as heat source are simulated from energetic and exergetic points of view. First configuration was basic steam Rankine cycle with PARABOLIC TROUGH solar COLLECTOR (PTSC) as heat source, and other configurations of the combined cycle worked as follows: In the second configuration (combined cycle with intermediate heat exchanger), with the increase of steam condenser pressure, heat dissipation in condenser is used as heat source for bottoming organic Rankine cycle and in the third configuration (combined cycle without intermediate heat exchanger), reduced-temperature solar fluid moving output of steam Rankine cycle acted as the organic Rankine cycle heat source. Simulation results in the basic input state show that third configuration has the maximum amount of work and irreversibility and second configuration has the minimum amount of work and irreversibility which, in this case, increase in the steam cycle condenser pressure leads to the reduction of work of combined cycle with intermediate heat exchanger, even lower than the simple steam cycle. On the other hand, second configuration has the maximum solar energy and exergy efficiency among three configurations which is due to the reduction of COLLECTOR area required in this configuration.

In the present work the efficiency of a solar PARABOLIC TROUGH has been investigated experimentally. PARABOLIC TROUGH solar COLLECTORs constitute a proven source of thermal energy for industrial process heat and power generation. The impact of using the partially porous media in the absorber on the efficiency of PTC (PARABOLIC TROUGH COLLECTOR) has been investigated. The porosity of copper foam is 0. 9 and its pore density is 30 PPI (pores per inch). The experiments were performed for different volume flow rates from 0. 5 to 1. 5 L/min. and the ASHRAE 93 standard was used to test the solar COLLECTOR’ s performance. Results illustrate that using metal foam in the absorber has a positive impact on the COLLECTOR efficiency and increases the pressure drop in the absorber. When absorber is filled with metal foam, the overall loss coefficient UL decreases 45% and it causes to increase efficiency because less energy is lost.