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This experimental study aims at investigating on the performance of a high temperature solar water heating system. To approach the high temperature, a porous-medium concentrated solar collector equipped with a focused solar heliostat were proposed. The proposed system comprised of two parts: a 0.7x0.7-m² porous medium receiver, was installed on a 3...
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... Porous media can be defined as an unconsolidated solid with open space pore structures to enable a fluid to pass through it. Porous media technology has been an attractive research topic in several engineering fields, such as solid fuel combustion [3], solar thermal systems [16,17], and steam generation [18,19]. Compared to the conventional thermal systems, all heat transfer modes, especially conduction and radiation, can be enhanced by porous media technology application. ...
Nowadays, energy crisis and environmental problems become the important issues affect all lives on the earth. All fossil-based energy will be depleted within the next few-ten years, if it is used at this current rate. Utilizations of renewable energy via efficient system poses an opportunity to address both fossil fuel depletion and environmental issues simultaneously. Among all renewable energies, biomass is one of the best forms of energy, in term of it can be actually managed by the curtain plan, e.g.: energy crop strategy. Gasification is one of the best thermal processes that converts liquid and solid hydrocarbon feedstocks into gas fuel, called syngas or producer gas (mainly comprises CO and H2). This research aims to improve the efficiency of the gasification reactor using Porous Media Heat Recuperator (PMHR). With the expectation that using this heat exchanger not only improve the gasification processes, but the producer gas temperature can be also reduced as the requirement for running the internal combustion engine (ICE). Charcoal, the carbonized product of wood or biomass, was selected as feedstock for this proposed system as it would produce a producer gas suitable for the ICE with low or free of tars uniform properties and low moisture content. The gasifier system was tested in a forced draught method using air as the gasifying agent. The experimental results shown that the efficiency of the proposed system with PMHR can be increased about 77% and the temperature of output producer gas can be increased for approximately 58%, compared with the conventional system.
... Heat transfer fluids with nanoparticles provide significant benefits in CSP solar power plants because of the enhancement of heat transfer, thermodynamic and thermophysical properties in absorbing heat induced by solar radiation. Enhanced heat transfer by the use nanofluids yields improvement to the receiver performance and absorption efficiency that may reduce the number of CSP collectors required to produce power using the basis fluid as thermal oil [28][29][30][31][32][33][34][35]. ...
In this paper, the performance of nanofluids in a Parabolic Trough Concentrating Solar Collector (CSP)-based power generation plant, an Organic Rankine Cycle (ORC), and a Thermal Energy Storage (TES) system is studied. This study is intended to investigate the enhancement effect and characteristics of nanofluids Al2O3, CuO, Fe3O4 and SiO2 in integrated concentrating solar power (CSP) with ORC, and TES under different solar radiations, angles of incidence, and different nanofluid concentrations. The refrigerant mixture used in the ORC loop to enhance the ORC efficiency is an environmentally sound quaternary mixture composed of R134a, R245fa, R125, R236fa. The results showed that the power absorbed, and power collected by the CSP collector and thermal energy stored in the storage tank are enhanced with the increase of the solar radiation. It was also found that the CSP hybrid system efficiency has been enhanced mainly by the increase of the solar radiation and higher nanofluid concentrations over the thermal oil as base fluid. Also, the study concludes that the nanofluid CuO outperforms the other nanofluids—Al2O3, Fe3O4 and SiO2—and has the highest CSP solar collector performance compared to the other nanofluids and thermal oil base fluid under study at similar conditions. Finally, it was found that the model’s prediction compares fairly with data reported in the literature; however, some discrepancies exist between the model’s prediction and the experimental data.
Solar energy is a promising renewable source to support the growing energy demand. This energy is widely harnessed for solar water heating systems to provide hot water for both domestic and industrial sectors thus reducing use of conventional energy sources. In this work, a concentrated solar water heater (CSWH) system is designed and fabricated at IIT Jodhpur. The main objectives are development of a point focus based direct solar water heating system and preliminary experiment based evaluation of the designed system. The system envisages a flux concentration of 100 Suns, which will enable receiver area reduction and the use of other heat transfer fluids like oil in future. The CSWH system consists of (a) receiver and (b) parabolic dish with two-axis sun tracking provision. In the conventional solar water heater system the irradiance from sun is directly collected by the collector whereas in concentrated solar water heater the reflected irradiance is received by the receiver. The reflector consists of a reflecting surface mounted on a parabolic structure and the cavity receiver consists of consists of a serpentine copper tube exposed to concentrated irradiance. The receiver will be insulated from top in order to prevent heat loss from one of its surface. An optical model of parabolic dish and receiver has been developed using TracePro software. This model is used as reference to generate the flux density distribution. The experimental setup consists of a parabolic dish, a receiver with thermocouples, a Coriolis flow meter, pump, water tank and NI DAQ. Coriolis flow meter is used to measure the mass flow rate in the system. K-type thermocouples are attached on to the receiver and the temperature is recorded using NI DAQ system. The theoretical geometric concentration ratio predicted is 115 but from the experiment a flux concentration ratio 94 is measured.
