AN INVESTIGATION ON A SOLAR CHIMNEY MODEL

Abstract

A solar chimney system (SCS) is a solar thermal power plant utilizing a combination of solar air collector and central updraft tube to generate a solar induced convective flow which drives pressure staged turbines to generate electricity. In the present work, an experimental setup model at the mechanical engineering department of Al-Azhar University was erected. Two geometrical parameters (chimney height, H and collector inlet height, h) have been investigated. The model collector radius, R is fixed at 1 m. The chimney diameter, d is fixed at 0.2 m and its height, H was varied from 2 m to 4 m. The collector inlet height, h was varied from 0.04 m to 0.08 m. Air velocity and temperature variation with time at chimney inlet have been measured as well as in canopy. The results show that the collector inlet height, h of 0.04 m and the chimney height, H of 4 m providing an optimum configuration for the constructed solar chimney model. The velocity and temperature profiles in the chimney was modeled by CFD analysis based on the same model dimensions. The CFD simulation was compared with the experimental data of the solar chimney model and a good agreement is noticed. ‫ﻣﻠﺨﺺ‬ : ‫ﻓﻲ‬ ‫ﻓﺮق‬ ‫ﯾﺤﺪث‬ ‫ﻣﻤﺎ‬ ‫اﻟﻤﺠﻤﻊ‬ ‫داﺧﻞ‬ ‫اﻟﮭﻮاء‬ ‫ﺗﺴﺨﯿﻦ‬ ‫ﻓﻲ‬ ‫اﻟﺸﻤﺴﯿﺔ‬ ‫اﻟﻄﺎﻗﺔ‬ ‫ﺗﺴﺘﺨﺪم‬ ‫ﻓﯿﮭﺎ‬ ‫اﻟﺸﻤﺴﯿﺔ‬ ‫اﻟﻤﺪﺧﻨﺔ‬ ‫ﺑﺎﺳﺘﺨﺪام‬ ‫اﻟﻄﺎﻗﺔ‬ ‫ﺗﻮﻟﯿﺪ‬ ‫ﻣﺤﻄﺎت‬ ‫ﻓﯿﻨﺘﺞ‬ ‫وﺧﺎرﺟﮭﺎ‬ ‫اﻟﻤﺪﺧﻨﺔ‬ ‫داﺧﻞ‬ ‫ﺑﯿﻦ‬ ‫اﻟﺤﺮارة‬ ‫درﺟﺎت‬ ‫ﺗﺮﺑﯿﻨﺎت‬ ‫ﺗﺸﻐﯿﻞ‬ ‫ﻓﻲ‬ ‫ﯾﺴﺘﺨﺪم‬ ‫اﻟﻀﻐﻂ‬ ‫ﻓﻲ‬ ‫ﻓﺮق‬ ‫ﻋﻨﮫ‬ ‫ھﻮاﺋﯿﺔ‬ ‫اﻟﻜﮭﺮﺑﺎء‬ ‫ﻻﻧﺘﺎج‬. ‫اﻷﺑﻌﺎد‬ ‫اﻟﻤﺤﻄﺔ‬ ‫أداء‬ ‫ﻋﻠﻲ‬ ‫اﻟﻤﺆﺛﺮة‬ ‫اﻟﻌﻮاﻣﻞ‬ ‫اھﻢ‬ ‫ﻣﻦ‬ ‫ﺗﻌﺘﺒﺮ‬ ‫ﺑﺎﻟﻤﺤﻄﺔ‬ ‫اﻟﺨﺎﺻﺔ‬ ‫اﻟﮭﻨﺪﺳﯿﺔ‬. ‫ﺗﻢ‬ ‫اﻟﺸﻤﺴﯿﺔ‬ ‫ﻟﻠﻤﺪﺧﻨﺔ‬ ‫ﻧﻤﻮذج‬ ‫ﻋﻠﻲ‬ ‫ﻣﻌﻤﻠﯿﺔ‬ ‫دراﺳﺔ‬ ‫ﻋﻤﻞ‬ ‫ﺗﻢ‬ ‫اﻻزھﺮ‬ ‫ﺑﺠﺎﻣﻌﺔ‬ ‫اﻟﻤﯿﻜﺎﻧﯿﻜﯿﺔ‬ ‫اﻟﮭﻨﺪﺳﺔ‬ ‫ﺑﻘﺴﻢ‬ ‫إﻧﺸﺎؤه‬. ‫اﻟﻘﯿﺎﺳﺎت‬ ‫إﺟﺮاء‬ ‫ﺗﻢ‬ ‫ﻣﻊ‬ ‫اﻟﺤﺮارة‬ ‫ودرﺟﺎت‬ ‫اﻟﺴﺮﻋﺔ‬ ‫ﺗﻐﯿﺮ‬ ‫ﻣﻨﺤﻨﯿﺎت‬ ‫ورﺳﻢ‬ ‫اﻟﻤﻄﻠﻮﺑﺔ‬ ‫اﻟﺰﻣﻦ‬. ‫ﺟﯿﺪ‬ ‫ﺗﻮاﻓﻖ‬ ‫ﺑﯿﻨﮭﻢ‬ ‫ﻓﻮﺟﺪ‬ ‫اﻟﻤﺤﺎﻛﺎة‬ ‫ﻧﻤﻮذج‬ ‫وﻗﯿﺎﺳﺎت‬ ‫اﻟﻤﻌﻤﻠﯿﺔ‬ ‫اﻟﻘﯿﺎﺳﺎت‬ ‫ﺑﯿﻦ‬ ‫ﻣﻘﺎرﻧﺔ‬ ‫ﻋﻤﻞ‬ ‫وﺗﻢ‬ ‫ﻟﻠﻨﻤﻮذج‬ ‫ﻣﺤﺎﻛﺎة‬ ‫ﻋﻤﻞ‬ ‫ﺗﻢ‬ .