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A thermodynamic analysis was performed on a newly developed concentrated solar power (CSP) technology known as the Cross-Linear (CL), which addresses the issue of cosine loss in conventional CSP technology. The analytical model has been developed and validated using experimental data collected at the experimental site situated in Bhopal, India. The analysis was performed under direct normal irradiance of 775 W/m2 with the key objective to determine the optimum inlet condition of the heat transfer fluid (HTF) considering three optimization parameters: HTF outlet temperature, energy, and exergy efficiency of the receiver. Also, the exergy of the solar field is investigated depending on the available solar irradiation throughout the day for three different configurations of the heliostat field. After a comprehensive analysis of the results, the optimal air inlet temperature range was observed to be between 373 and 423 K, and the optimal air mass flow rate was overserved to be 0.0925 kg/s (333 kg/h), which provides energy and exergy efficiency values within 50% to 60% and 28% to 34%, respectively. The maximum electrical exergy efficiency for 30 kW plant capacity is observed to be around 70% at solar noon with a cosine factor of around 0.9 for 4-hour duration. [ABSTRACT FROM AUTHOR]

Cavity receiver integrated with parabolic dish collector is an essential component of the solar thermal energy conversion process for high-temperature applications, such as power generations, process heat demand, and industrial applications. This paper is focused on a comprehensive review and representation of research on solar cavity receiver. The majority of research concentrated on the highest thermal efficiency with the least amount of heat loss and their interactions with solar cavity receiver geometries. The review consists of various combinations of the receiver's geometries along with different heat transfer fluids, and it also give suggestions to improve the performance of the system based on optimized geometrical and operational parameters. The existing literature primarily focused on the experimental and numerical procedures used with different technologies to improve the efficiency of the solar power system. The decrements in heat losses experienced during the conversion of solar energy into thermal energy is used to determine the efficiency of parabolic dish collector systems. The evaluation of convection and radiation losses is essential to improve the thermal performance of the solar power system. Heat loss models and correlations have been discussed to understand the heat loss mechanism for cavity receiver. The present study analyzes a wide range of parameters that affect cavity receiver performance, including aspect ratio, concentration ratio, optimum receiver length, receiver aperture, tilt angle, and inclination angle. The benefits of air curtains, receiver coatings, and other heat transfer enhancement techniques are also briefly reviewed and expected to be useful in modeling and design of cavity receiver with parabolic dish collector system to improve overall performance. One of the most significant aspects of this article is that it covers a wide range of cavity literature encountered in other engineering systems, power generation, and a wide range of other industrial and domestic applications. The cylindrical cavity receiver has shown an average thermal efficiency of 63.9 % using nano-fluid and 56.44 % for pure thermal oil. The hemispherical cavity receiver has shown the daily mean thermal efficiency of 82.66 % using novel soybean oil-based MXene nanofluid. Under the constant parameters, and solar irradiation intensity 300 to 1100 W / m 2 , the receiver thermal efficiency varies from 80% to 90%. In case of conical cavity receiver, the maximum thermal efficiency achieved with thermal oil is 78.7%. [ABSTRACT FROM AUTHOR]

This article presents an optical investigation of a corrugation cavity receiver for a 100 m2 parabolic dish collector (PDC). The performance of PDC depends on the selection of the receiver and its mounting distance from the collector base (H) to receive a high amount of reflected radiation. This work performs optical modeling for PDC with a designed corrugation cavity receiver using commercial software, ASAP® 2013. The motivation for this study is derived from the fact that the entrapped internal reflection within the receiver optimizes the system's optical efficiency. The receiver geometry is such that it attributes to increasing internal reflection and average heat flux intensification. The present optical model is validated with the available literature. The influential geometrical and optical parameters of the receiver have been optimized by simulation by varying the aperture diameter (da,r) from 0.504 to 0.604 m, surface absorptivity (α) from 75 to 95%, receiver coil's outer and inner pitch (Po and Pi) from 0.00667 to 0.00909 m, and angle of taper (θi) from 50° to 56° for H = 5.35–5.65 m. The performance of the optimized receiver is compared with the conical cavity receiver and is found to be excellent among all values of H. This optical modeling can be expected to be helpful for engineers and researchers in designing the optimized optical receiver for solar parabolic dish collector systems. [ABSTRACT FROM AUTHOR]

The high efficiency of concentrated solar power (CSP) in energy conversion makes it a very attractive device for using solar energy as a substitute of nonrenewable energy sources. The open volumetric receiver plays an important role in the performance of a CSP. The optimized design of solar receiver implies the thorough knowledge of the heat transfer between the air and the foam and of the temperature distribution in the receiver. Heat transfer in the cylindrical SiC porous volumetric receiver of a solar tower, undergoing the impact of concentrated solar radiation, is investigated numerically in this paper. Governing equations are written with the volume averaging technique. A two-equation model for the energy equation, under the local thermal nonequilibrium assumption, is used. Numerical simulations are carried out through the commercial code COMSOL Multiphysics. The solid and fluid temperatures, the fluid velocity and the pressure drop, for various boundary and morphological conditions, are predicted and discussed. The receiver efficiency is finally maximized carrying out an extended parametric analysis of process parameters. [ABSTRACT FROM AUTHOR]

This article presents the use of a wire mesh in optimising the performance of two volumetric solar receivers that use oil as a heat transfer fluid. Computational fluid dynamics models have been used to optimise the receivers. Varied parameters (including the use of a wire mesh) of the receiver models were changed in the optimisation process. Based on the models, prototype receivers were developed and tested. After that, the models were validated against experiments and the results compare well. The results indicate that the use of a wire mesh placed inside a receiver improves its performance. An optimal wire mesh porosity was found as ≈0.95 mainly because the efficiency is increased without inducing an adverse pressure drop inside the receiver. [ABSTRACT FROM PUBLISHER]