Research And Development Of Strength Design Software For Desulfurization Tower

As the domestic flue gas emission standard continues to improve,in recent years quite a considerable number of desulfurization towers have been improved or newly built.As a result traditional manual calculation design method is unable to meet the growing demand for design.By now,there is no design standard of flue gas desulfurization tower in home.The strength design of large flue gas desulfurization tower mainly relies on the engineering experience,and it is lack of theoretical basis.As the desulfurization tower is mainly manufactured in the field through tailor-welded blanks,the manufacturing error is uneasy to control,the imperfections are easy to exceed the standard value,so it is urgent for enterprises to get a desulfurization tower strength calculating method that can take the out of limit imperfections into consideration.From this point,this paper researches into the strength design method of desulfurization tower and the design software of the strength of the desulfurization tower is programmed.The structural characteristics of the desulfurization tower are analyzed to propose the basic concepts of the structure design method of the desulfurization tower.According to the structural analysis result,the demand analysis of the design software is carried out,thus the frame and the realization method of the desulfurization tower strength design software is also planned.By consulting the design method used in desulfurization tower design nowadays and the tower design standard,the specific strength design method of the desulfurization tower to be used in the software determined is determined.Based on the design calculation method presented in this paper,the shape correction factor is proposed to take the influence of the out of limit imperfection into design consideration.The structure parameters of axial compression cylinder and cone specimens are obtained according to the D/t ratio and the half tapering angle of cone in large desulfurization tower by equivalent method.By using the laser scanner,the surface profile data of the cylinder and cone specimens are obtained,and the imperfection amplitude of the specimens is manufactured to exceed the standard limit.To obtain the critical buckling load of the cylinder and cone samples,the axial compression test is carried out on the samples.Meanwhile,finite element simulations of the consistent imperfect buckling mode model,scanning model and cylinder/cone simplified Fourier series model are carried out with ABAQUS and ANSYS respectively.The ideal elastic-plastic material model is adopted in the simulation.The result shows that the critical buckling loads of the scanning model are slightly larger than theexperimental value;the critical buckling loads of the cylinder/cone simplified Fourier series model are in good agreement with the scanning model,also slightly larger than the experimental value;the buckling load of the consistent imperfect buckling mode model are far smaller than the experimental value,this method is too conservative.Thus to the thin-walled cylindrical structure and thin-walled cone structure with half tapering angle close to 30 degrees and D/t ratio close to the desulfurization tower,the cylinder/cone simplified Fourier series model can accurately describe their imperfections.to obtain the critical loads of cylinder and cone components with imperfection amplitudes exceeding the standard in desulfurization tower.The shape correction factor is obtained by comparing the critical loads with the standard calculation results.The desulfurization tower design software is completed according to the frame and the realization method made in chapter two and Java SE is adopted as the programming platform.Also the shape correction factor in included in the software,which is adopted according to the imperfection amplitude provide by the enterprise,the cylinder/cone simplified Fourier series model and the formula calculation method by comparing the simulation critical loads with the formula critical load is added in the software.To verify the correctness and reasonableness,the software is adopted by the enterprise in business use and the feedback is positive.To sum up,the strength design software of the desulfurization tower obtained in this paper is reliable.And it is capable of design the desulfurization tower which has imperfections that exceed the standard a bit.