Chemical Engineering
Saeed Raveshi; Amin Ahmadpour
Abstract
Nowadays energy and electricity production is one of the major concern of governments. Electricity generation by solar systems is considered as one of the alternative for fossil fuels. There is a surge in the use of the solar chimney power plant in the recent years which accomplishes the task of converting ...
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Nowadays energy and electricity production is one of the major concern of governments. Electricity generation by solar systems is considered as one of the alternative for fossil fuels. There is a surge in the use of the solar chimney power plant in the recent years which accomplishes the task of converting solar energy into kinetic energy. In this study a numerical simulation and geometrical parameters optimization of the solar chimney is discussed. In this paper, solar chimney prototype in Manzanares, Spain, as a practical example is used. To explore the geometric modifications on the system performance (output power and efficiency), effect of chimney height, collector radius and collector height is studied. A numerical simulation in this paper were used to evaluate the performance of a solar chimney power plant system, in which the effects of various parameters on the relative static pressure, driving force, power output and efficiency have been further investigated. In order to validate the present work, upwind velocity in the solar chimney was compared with an experimental model.
Chemical Engineering
Hossein Hosseini; Asef Zare
Abstract
Gas turbines are usually designed in such a way that the pressure of hot gases at the exit of the turbine and after the last moving blade is slightly lower than the atmospheric pressure. Therefore, in order to overcome the ambient pressure, a divergent duct is considered at the gas turbine outlet, and ...
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Gas turbines are usually designed in such a way that the pressure of hot gases at the exit of the turbine and after the last moving blade is slightly lower than the atmospheric pressure. Therefore, in order to overcome the ambient pressure, a divergent duct is considered at the gas turbine outlet, and in this way, the exhaust gases, which have a relatively high temperature, are sent to the surrounding atmosphere through the exhaust. The useful output power is transferred to the compressor and then to the generator. Today, the use of gas turbines in power plants and as a generator of electricity is very valuable. In addition, they are widely used in various industries such as space industries, marine platforms, petrochemical industries, etc. These turbines can be useful especially in parts of the electricity industry that require quick installation and commissioning, as well as in cases where the national electricity grid is lost. Speed in construction and installation, low investment cost and low maintenance cost, light weight and the possibility of using multiple fuels are among the advantages of gas turbines compared to other power plants. Current gas turbines are operated with fuels such as natural gas, diesel, low thermal value gases, methane, crude oil, oil. Regarding the disadvantages of these turbines, we can mention the low efficiency and the need for major repairs after fewer working hours and the changes in power and efficiency due to atmospheric changes.
