Combining with Jeffery :quation and mechanics model of fixed point of Euler rigid btdy, the mechanism and method of short fiber radial orientrion and characteristics of movement in tread extrusion process were studie...Combining with Jeffery :quation and mechanics model of fixed point of Euler rigid btdy, the mechanism and method of short fiber radial orientrion and characteristics of movement in tread extrusion process were studied. The influences of tension flow field and shear flow field in flow channel on short fiber orientation trove been systemically analyzed. The extrusion die, which had a hinder dam by adopting such principle, was designed. The results show that the expansion ratio and expanding angle of cross section are the key factors to determine the radial orientation of short fiber. Mathematical model of short fiber radial orientation was established. The results also show that the best expansion ratio is 3 - 4, the expanding angle is 75°, obtaining the average orientation angle between 70°- 80°, and the rationality of the radial oriented mechanism and the mathematical model are verified.展开更多
Due to the electrical anisotropy of carbon fiber reinforced polymer(CFRP),this paper presents a method to inverse the anisotropic conductivity of unidirectional CFRP laminate using eddy current testing(ECT). The relat...Due to the electrical anisotropy of carbon fiber reinforced polymer(CFRP),this paper presents a method to inverse the anisotropic conductivity of unidirectional CFRP laminate using eddy current testing(ECT). The relationship between the conductivity and probe signal of ECT is studied by means of numerical simulation. Finally,the accuracy of inversion result is improved by optimizing the initial conductivity by use of experimental data.展开更多
Based on analyzing risk factors of diversion project,synthetic risk rate and engineering insurance period,the frequency and distribution law of loss are researched on the grounds that foundation pit is submerged after...Based on analyzing risk factors of diversion project,synthetic risk rate and engineering insurance period,the frequency and distribution law of loss are researched on the grounds that foundation pit is submerged after diversion project ceases to be effective.And then,the standpoint that these total loss is subject to non-homogeneous compound Poisson processes is put forward.Furthermore,the collective risk model of the total loss about engineering insurance is established on the basis of construction diversion project risk.Ultimately,insurance ratemaking method for construction engineering risk and its mathematical expression are presented,which provides theoretical method for the insurance ratemaking of hydropower engineering to some extent.展开更多
基金National Natural Science Foundation of China(No.50775116)
文摘Combining with Jeffery :quation and mechanics model of fixed point of Euler rigid btdy, the mechanism and method of short fiber radial orientrion and characteristics of movement in tread extrusion process were studied. The influences of tension flow field and shear flow field in flow channel on short fiber orientation trove been systemically analyzed. The extrusion die, which had a hinder dam by adopting such principle, was designed. The results show that the expansion ratio and expanding angle of cross section are the key factors to determine the radial orientation of short fiber. Mathematical model of short fiber radial orientation was established. The results also show that the best expansion ratio is 3 - 4, the expanding angle is 75°, obtaining the average orientation angle between 70°- 80°, and the rationality of the radial oriented mechanism and the mathematical model are verified.
基金supported by the research fund of State Key Laboratory of Mechanics and Control of Mechanical Structures(Nanjing University of Aeronautics and astronautics)(No. MCMS-I-0518K01&MCMSI-0519G02)Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)the Natural Science Funding (No. 51875277)
文摘Due to the electrical anisotropy of carbon fiber reinforced polymer(CFRP),this paper presents a method to inverse the anisotropic conductivity of unidirectional CFRP laminate using eddy current testing(ECT). The relationship between the conductivity and probe signal of ECT is studied by means of numerical simulation. Finally,the accuracy of inversion result is improved by optimizing the initial conductivity by use of experimental data.
基金Project of the National Eleventh Five-year Research Program of China (No.2008BAB29B02)National Natural Science Foundation of China(No.51079115)
文摘Based on analyzing risk factors of diversion project,synthetic risk rate and engineering insurance period,the frequency and distribution law of loss are researched on the grounds that foundation pit is submerged after diversion project ceases to be effective.And then,the standpoint that these total loss is subject to non-homogeneous compound Poisson processes is put forward.Furthermore,the collective risk model of the total loss about engineering insurance is established on the basis of construction diversion project risk.Ultimately,insurance ratemaking method for construction engineering risk and its mathematical expression are presented,which provides theoretical method for the insurance ratemaking of hydropower engineering to some extent.