* Where, E: Experimental, T: Theoretical. Table 1 (continued)
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Abstract: This paper presents a review of the design parameters, mathematical techniques and simulations used in the design of parabolic trough solar systems, along with a review on their applications. Recent studies that analyze the deployment of solar parabolic trough collectors (SPTC) in different countries and the operational SPTC plants are also presented and discussed. The paper also discusses the different kinds of software and test methods of solar collectors developed since 1981 which can be distinguished by their particular mathematical models or tracking techniques. In particular, since the mathematical models are especially required for the design, analysis, testing and validation of the systems results as they provide an approximation of the dynamic behavior of the physical properties of the system, they are discussed in depth. The mathematical models allow the calculation of different parameters of the solar parabolic trough system, the angle of inclination of the collecting surface and the forces acting on the system. The validity and experimental validation of the major mathematical models on practical solar parabolic trough concentrators, receivers and other components of different dimension are also reviewed. The paper showed the optical efficiency values are close to 63% and the theoretical peak optical efficiency reached 75%.
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Solar Energy and Thermal Energy Storage Systems Parabolic Trough Collector Related Papers Abstract: Parabolic Trough Collectors are widespread in CSP applications. Their adoption is less developed in industrial heat demand applications. In the present thesis the design and test of two prototypes of PTC for the thermal loads in the range 80-250 °C is described. A mathematical model has also been developed to predict optical efficiency and thermal losses for any PTC. The model has been validated through comparison with the experimental results on the prototypes. Then it has been included in a custom-built simulation environment to predict yearly performances of a PTC field coupled with an industrial process heat demand. Energetic results are shown and final considerations are drawn for this application.
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Abstract: The performance of the parabolic collector depends on several factors such as the size and shape of the parabolic trough collector, shape and area of the focal heat exchanger and optical properties. Another very important parameter that depends on the position and location of the solar collector is a value of the intensity solar irradiation. The performance measurement of the collector was carried out in the northern part of Slovakia, in the city Zilina. The captured solar energy in the form of sunlight by solar trough collector was concentrated to focal heat exchanger. Subsequently this energy was changing into a thermal energy. The thermal energy was led away from the focal heat exchanger by means of a heat-transfer medium. This paper deals with performance measurement of parameters of the parabolic trough collector with absorption area 10.25 m and real area of focal heat exchanger 1.66 m.
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Abstract: This paper was concerned with an experimental study of parabolic trough collector's with its sun tracking system designed and manufactured. To facilitate rapid diffusion and widespread use of solar energy, the systems should also be easy to install, operate and maintain. In order to improve the performance of solar concentrator, different geometries and different types of reflectors were evaluated with respect to their optical and energy conversion efficiency. To assure good performance and long technical lifetime of a concentrating system, the solar reflectance of the reflectors must be high and long term stable. Therefore, different types of reflector materials and absorbing materials were analyzed in this work; also the optical properties and degradation of the reflecting surfaces were assessed. During the research, focus has shifted from evaluation of the performance of concentrating solar collector to analysis of the optical properties of reflector and absorbing materials. The shift of focus was motivated by the need to assess long term system performance and possibilities of optimizing the optical efficiency or reducing costs by using new types of reflector materials and absorbing materials. For the design of the SPTC frame, a finite element model had been developed and used to check the capability of the structure to absorb torsion and bending forces, under dead and wind loads. The SPTC was fabricated in local workshops and the sun tracking system was assembled using electric and electronic components in the market, while the mechanical components making up the driving system were procured from the second hand market. The fabricated SPTC and its tracking system were tested outdoors in the campus under dry and wet weather. The experimental results obtained have shown that the obtained characteristic curve of the tested Aluminium collector is considerably lower than that of a mirror collector which can be attributed to the higher thermal losses for the lack of the evacuated glass envelope around the absorbing tube, the end losses of the collector and the inaccuracy in tracking the sun. However, the mirror collector efficiency is about 8% higher than that of Aluminium under dry weather condition, which is fairly acceptable, considering that it was the first attempt to manufacture such mirror collector locally. Thus, the overall aim of the 38 work presented in this research was to investigate the possibilities to increase the efficiency of the solar energy systems, and thereby reducing the cost of the electricity or heat that was produced. Attention was also given to the long term durability and robustness of the system. The basic hypothesis was that the use of durable, light weight, low cost reflectors for increasing the concentrator efficiency.
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Abstract: This paper presents the design, construction and investigates an experimental study of a parabolic Trough Solar Collector (PTSC). It is constructed of multi – piece glass mirror to form the parabolic reflector (1.8 m ? 2.8 m) its form were checked with help of a laser and carbon steel rectangular as receiver. Sun tracker has been developed (using two – axis) to track solar PTSC according to the direction of beam propagation of solar radiation. Using synthetic oil as a heat transfer its capability to heat transfer and load high temperature (?400 oc). The storage tank is fabricated with stainless steel of size 50 L. The experimental tests have been carried out in Baghdad climatic conditions (33.3o N, 44.4o E) during selective days of the months October and November. The performance of PTSC is evaluated using outdoor experimental measurements including the useful heat gain, the thermal instantaneous efficiency and the energy gained by the storage tank oil. The storage tank oil temperature is increased from 30oc at 9:30h to 136oc at 13:30h without draw – off oil. The experimental result shows the average thermal efficiency was 42% which is fairly acceptable assessment results of a PTSC locally.
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Abstract: An experimental facility for the acquisition of reliable data from parabolic trough solar collectors (PTCs) is established to develop a robust analytical model. The wide ranges of heat transfer fluid (HTF) flowrate (0.0372-0.1072 kg/s) and solar radiation (400-900 W/m2) are used to achieve PTC parameters such as the outlet temperature of HTF heat loss and temperature distribution. Vacuum conditions in the receiver are considered to be effective in terms of thermal efficiency. Also, three types of HTF including two oil fluids (Syltherm 800 and S2) and water were examined. The temperature distribution shows that when Syltherm or S2 passes through the absorber tube, the outlet temperature is higher than water: 2.84% for Syltherm and 3.72 % for S2. Since the absorber tube temperature is much higher than water, the heat loss in this condition is considered for oil HTF. Notables, the results show that using the vacuum tube can diminish heat loss for the oil HTF. The effect of solar intens...
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