الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The demand for indoor air quality and thermal comfort increases dramatically on a global scale, and it leads to an increase in the demand for electric energy. However, the energy and global warming crises have had an unavoidable impact on human life. Thus, it is necessary to replace industrial ventilation, heating and cooling systems with passive systems that utilize renewable sources of energy such as solar and wind energy. This study presents a theoretical and experimental investigation of the thermal performance of solar chimneys under the meteorological conditions of El-Arish City, North Sinai, Egypt. The experimental investigation focused on changing the gap width as the geometrical parameter and integrating a heat storage method by adding either a layer of sensible heat storage material (Concrete) or a phase change material (Bitumen) into the solar chimney. The theoretical study was accomplished using the ANSYS workbench 2019 R1 package. A 2-D model of the side cross-section of the test rig model was developed using ANSYS SpaceClaim. The suggested length of the tested models varied between 1 and 2 m while different gap width values ranging between 2.5 and 10 cm were used. Further, several values for the inclination angle have been used from 0° to 90° in step 15 degree. The performance of the solar chimney was studied under these configurations and variable solar radiation of 400, 600, and 800 W/m2. The experimental results showed that adding a layer of sensible heat storage material improved the thermal efficiency of the solar chimney while backing the absorber with a layer of latent heat storage material further improved the solar chimney efficiency. The simulation results showed that increasing the chimney length increases the airflow velocity and the air temperature difference between the outlet and inlet of the chimney. While increasing the gap width decreases the air temperature difference. It also was found that among the studied inclination angles, the chimney with 90o achieved the best velocity distribution and lowest temperature difference. Otherwise, the chimneys with inclination angles of 30o, 45o and 60o achieved a performance balanced between the reasonable velocity and temperature difference. The experimental results showed that the solar chimneys with gap widths of 2.5, 5, and 10 cm achieved an average daily efficiency of 21.1%, 24.1%, and 16.3% respectively. The air temperature difference achieved by chimneys is 18 °C, 14.5 °C and 5.6 °C respectively. It also showed that integrating the solar chimney with concrete and bitumen increased the air mass flow rate through the device with a daily average value of about 24% and 32% respectively. The comparison between experimental and theoretical results is quite satisfactory. Additionally, a case study on a small-scale 3-D room model attached with a chimney in different configurations (vertical, inclined and combined). The room has dimensions of 1.0 × 1.0 × 1.0 m3 with an air inlet opening of 30 ×30 cm2, while the chimney dimensions are 1.0 m × 1.0 m with a gap width of 10 cm. The study was concerned with the effect of chimney configuration on airflow behavior and distribution in the room. from the results, it was concluded that the vertical chimney configuration is the worst according to the achieved mass flow rate and air distribution. While the combined configuration achieved the best air distribution in the room. Finally, the combined chimney yields the highest air flow velocity, suitable air distribution and the highest airflow rate.