Research On Simulation Of Solar Chimney Power System

Our country has a strong manufacturing power with a large population. And china isin the lower-end of the whole industry chain under the background of the economicglobalization. By now, a large share of the sustained economic growth in China hasbeen established on the basis of high energy consumption. We have to change theenergy structure and develop the renewable energy under the current situation ofgrowing energy-extensive consumption and high pollution. Solar Updraft Tower Powertechnology is a kind of new technology that can push forward the turbine system togenerate electricity. Such technology utilizes the solar radiation to heat up the air in thecollector and the upward thermal current was finally formed under the section of gravityand chimney. The station of the solar updraft tower has many advantages as simpleoperation and maintenance, zero release, need no water, generate electricity constantlyday and night and so on.This paper focus on the thermodynamic knowledge and makes theoretical analysison the heat transfer and flow in the internal part of the station of the solar updraft tower.What’s more, the paper performs a numerical simulation on the operation of the powergeneration system through CFD software ANSYS-Fluent. Additionally, the simulationand optimization of several aspects in this system are finished in this paper, such as thedensity model of the air in this system, impacts on the structure parameter of the powerstation, temperature distribution of the energy storage layer and so on. In this paper, anumber of meaningful conclusions are listed below.Firstly, three models of air density in the station of the solar updraft tower arepointed out which are compressible ideal gas, incompressible ideal gas, and Boussinesq.This paper also makes a simulated calculation in the same situation and makes acomparison on the air density distribution with different models. And in the small and mid-sized system, such system errors that caused by the air compressibility is very small.In order to decrease the calculated amount of the numerical simulation, we can neglectthe influence of the air density which caused by the change of the gage pressuredistribution inside the system and use the model of Boussinesq directly.Secondly, this paper also does an in-depth research on the operational mechanism ofthis system. It analyses that the structure parameters and external conditions affected thesystem performance greatly and it finally provides the relations between variousparameters. This paper adopts the Spanish prototype plant as a physical model and useCFD to calculate some parameters as flow field, temperature field, pressure field,chimney rate and the maximum system draft with different solar radiations and structureparameters at no load condition. Besides, the paper optimizes the structure parametersof the Spanish prototype plant.Last but not least, the paper analyses the heat accumulator of this power planttheoretically. A preliminary numerical analysis is made on the temperature withdifferent depth inside the heat accumulator which is changing in the solar radiation.Calculations show that such heat accumulators paved with sand and other similarmaterials have a better thermal inertia. It not only maintains the power plant to generateelectricity day and night but reduce the peak-vale difference of the power output.