23 research outputs found
Heat transfer and energy analysis of a solar air collector with smooth plate
No full textThe heat transfer and thermal performance of a single pass solar air heater a smooth plate was investigated experimentally. In the present paper, energy and heat transfer analysis of a solar air collector with smooth plate, this technique is used to determine the optimal thermal performance of flat plate solar air heater by considering the different system and operating parameters to obtain maximum thermal performance. Thermal performance is obtained for different mass flow rate varying in the array 0.0108–0.0202 kg/s with five values, solar intensity; tilt angle and ambient temperature. We discuss the thermal behavior of this type of collector with new design and with my proper construction. An experimental study was carried out on a prototype installed on the experimental tests platform within the University of Biskra in the Algeria. The effects of air mass flow rate, emissivity of channel plates and wind heat transfer coefficient on the accuracy of the criterion are also investigated
Experimental study of heat transfer and thermal performance with longitudinal fins of solar air heater
No full textAbstractThe thermal performance of a single pass solar air heater with five fins attached was investigated experimentally. Longitudinal fins were used inferior the absorber plate to increase the heat exchange and render the flow fluid in the channel uniform. The effect of mass flow rate of air on the outlet temperature, the heat transfer in the thickness of the solar collector, and the thermal efficiency were studied. Experiments were performed for two air mass flow rates of 0.012 and 0.016kgs−1. Moreover, the maximum efficiency values obtained for the 0.012 and 0.016kgs−1 with and without fins were 40.02%, 51.50% and 34.92%, 43.94%, respectively. A comparison of the results of the mass flow rates by solar collector with and without fins shows a substantial enhancement in the thermal efficiency
Aerodynamic shape optimization of a vertical-axis wind turbine with effect number of blades
No full textOur research consists of the experimental study of the vertical wind turbine of form H. The study represents the effect of the number of blades in the variation of the number of rotations of the vertical wind turbine, the speed ratio, torque, the power of the wind turbine, and the torque force. The H-shaped vertical axis wind turbine was carried out in the hall of the University of Biskra, where the research was manifested in the study of the dimensions imposed in the experiment from the length of the propeller and the extent of its curvature in the width of the propeller; we also recorded each of the numbers of rotations of vertical axis wind turbines. Evidently, It has been proven that the wind energy coefficient increases with the increase in the number of blades. It is further noted that a higher number of blades- equal to 20- gave a high wind speed of 15.2 m / s, the number of rotations equal to 239.2 rpm. The various parameters such as the power coefficient, the speed quotient, and the quotient of the area of the fluid passage section for each were established by a model with low errors and with a perfect approximation.Nuestra investigación consiste en el estudio experimental del aerogenerador vertical de forma H. El estudio representa el efecto del número de palas en la variación del número de rotaciones del aerogenerador vertical, la relación de velocidad par, la potencia de la turbina eólica y la fuerza de torsión. El aerogenerador de eje vertical en forma de H se llevó a cabo en el hall de la Universidad de Biskra, donde la investigación se manifestó en el estudio de las dimensiones impuestas en el experimento a partir de la longitud de la hélice y la extensión de su curvatura en el ancho. de la hélice; también registramos cada uno de los números de rotaciones de los aerogeneradores de eje vertical. Evidentemente, se ha comprobado que el coeficiente de energía eólica aumenta con el aumento del número de palas. Se observa además que un mayor número de palas, igual a 20, dio una alta velocidad del viento de 15,2 m / s, el número de rotaciones igual a 239,2 rpm. Los diversos parámetros como el coeficiente de potencia, el cociente de velocidad y el cociente del área de la sección de paso de fluido para cada uno fueron establecidos por un modelo con errores bajos y con una aproximación perfecta
THERMAL EFFICIENCY ANALYSIS OF A SINGLE-FLOW SOLAR AIR HEATER WITH DIFFERENT MASS FLOW RATES IN A SMOOTH PLATE
No full textEffect of the Tilt Angle of Natural Convection in A Solar Collector with Internal Longitudinal Fins,”
No full textAbstract-We present in this paper, a series of experimental tests carried out on a solar plan, with an area of 1.8236 m 2 capture, designed in the laboratory and tested in the region of Biskra. The complete experimental setup includes the measurement of global solar radiation, wind speed, airflow velocity and temperature and the ambient air at the inlet and outlet; optimize a tilt angle. The solar collector was oriented facing south Renewable and domestic energy source, and is essential components of a sustainable energy future. This paper deals with the influence of the tilt angle of solar collectors. The optimum angle is measured by searching for the values for which the total radiation on the collector surface is a maximum for a particular day or a specific period. An application of the model is done using the experimental data measured for Biskra in Algeria. For increasing the utilization efficiency of solar collectors, it is recommended that, if it is possible, the solar collector should be mounted at the monthly average tilt angle, and the slope adjusted once a month
Optimización de la forma aerodinámica de un aerogenerador de eje vertical con efecto número de palas
No full textOur research consists of the experimental study of the vertical wind turbine of form H. The study represents the effect of the number of blades in the variation of the number of rotations of the vertical wind turbine, the speed ratio, torque, the power of the wind turbine, and the torque force. The Hshaped vertical axis wind turbine was carried out in the hall of the University of Biskra, where the research was manifested in the study of the dimensions imposed in the experiment from the length of the propeller and the extent of its curvature in the width of the propeller; we also recorded each of the numbers of rotations of vertical axis wind turbines. Evidently, It has been proven that the wind energy coefficient increases with the increase in the number of blades. It is further noted that a higher number of blades- equal to 20- gave a high wind speed of 15.2 m / s, the number of rotations equal to 239.2 rpm. The various parameters such as the power coefficient, the speed quotient, and the quotient of the area of the fluid passage section for each were established by a model with low errors and with a perfect approximation.Nuestra investigación consiste en el estudio experimental del aerogenerador vertical de forma H. El estudio representa el efecto del número de palas en la variación del número de rotaciones del aerogenerador vertical, la relación de velocidad par, la potencia de la turbina eólica y la fuerza de torsión.El aerogenerador de eje vertical en forma de H se llevó a cabo en el hall de la Universidad de Biskra, donde la investigación se manifestó en el estudio de las dimensiones impuestas en el experimento a partir de la longitud de la hélice y la extensión de su curvatura en el ancho. de la hélice; también registramos cada uno de los números de rotaciones de los aerogeneradores de eje vertical. Evidentemente, se ha comprobado que el coeficiente de energía eólica aumenta con el aumento del número de palas. Se observa además que un mayor número de palas, igual a 20, dio una alta velocidad del viento de 15,2 m / s, el número de rotaciones igual a 239,2 rpm. Los diversos parámetros como el coeficiente de potencia, el cociente de velocidad y el cociente del área de la sección de paso de fluido para cada uno fueron establecidos por un modelo con errores bajos y con una aproximación perfecta
An experimental study and mathematical modeling of solar drying of moisture content of the mint, apricot, and green pepper
No full text
STUDY OF PRECIPITATION KINETICS OF AN Al-Mg-Si ALLOY USING DIFFERENTIAL SCANNING CALORIMETRY
No full textThis work has been carried out by differential scanning calorimetric (DSC) to study the precipitation kinetics in quenched and natural aging Al-Mg-Si alloy. DSC curves showed exothermic and endothermic peaks corresponding to the precipitation and the dissolution processes. The activation energy of the precipitation process has been calculated using Kissinger model. The results obtained showed a change in the activation energy values, the activation energy for the β″ and β determined for natural aging alloy were higher than that in the quenched alloy.</jats:p
