Optimization Of Trough Condenser Based On BIM Technology And Simulation Of Non-gaussian Wind Pressure

Since 1970s,as a renewable energy solar energy has been paid attention gradually and has entered a booming age.As a facility effectively and efficiently using solar energy,trough solar concentrator not only requires the function of converting solar energy into heat energy,but also a better stability of the structural system to ensure it operates well.Therefore,demand targets in several fields should be taken in consideration in the process of design and manufacture about the trough condenser,which needs systematic and holistic collaborative design.As a new tool integrated with design,construction,operation and management,BIM(Building Information Modeling)has been widely used in the design,construction,operation and so on.Firsty,this paper introduced the concept and characteristics of BIM,and its development at home and abroad.The design method of trough condenser is engaged with BIM,to illustrate the application of BIM in the co-design of trough solar concentrator system.Secondly,the structure of trough condenser determines the amount of steel is the main factor affecting its cost.To control cost,uniform design is employed to optimize the trough condenser in this paper.During this paper,the mirror displacement and bar stress are considered as constraints,triangular truss's rod sizes and the wing's rod sizes as quantitative parameters,and the initial cable tension as qualitative parameter.Then according to the parameters gained from optimizition,the three-dimensional BIM model of trough condenser including steel types,quantity,length,quality and other informations is modified to calculate the cost of steels.The result indicates that uniform design method can be used to optimize the structure of condenser with qualitative and quantitative factors.Under the constraints,the cost of the steels is reduced by 11.76%and the amount of steels is saved by 11.86%,which indicates that the result of optimization is satisfactory.The proposed method has a certain reference value for the complex optimization problems including quantitative parameters and qualitative parameters.The cost of steels according to the 3D BIM information model further demonstrates the validity of the optimization.Finally,the wind load is the main load of concentrator generally in the open.Affected by the vortex turbulence on the surface of the structure,the distribution of wind pressure in some aera of the morror is obviously non Gauss under some conditions.Based on the wind pressure time-history of a high-rise model tested by wind tunnel,considering the fractal characteristics of the fluctuating wind and the correlation distortion method,the non-Gaussian fluctuating wind pressure is simulated by adopting Weierstrass-Mandelbrot function.Comparing simulation results with experimental datas in the aspects of probability distribution,power spectrum,fractal box dimension,skewness and kurtosis,it showed better consistency.Therefore,it is feasible to simulate the fluctuating wind pressure with non-Gaussian characteristics by using fractal method.The method compensates the disadvantages of conventional linear filter and superposition of harmonic,and it also provides a reference for the simulation of non-Gaussian fluctuating wind pressure on the surface of condenser.