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772.
H. Korezlioglu G. Mazziotto J. Szpirglas 《Stochastic Processes and their Applications》1983,15(3):239-269
Nonlinear filtering equations for two-parameter semimartingales of a Brownian sheet are obtained by an extended reference probability method, also applicable to the known Gaussian linear models. 相似文献
773.
Hong Yuan 《中国科学G辑(英文版)》2008,51(6):678-686
Based on the dynamic equations of nonlinear large deflection of axisymmetric shallow shells of revolution, the nonlinear free
vibration and forced vibration of a corrugated shallow shell under concentrated load acting at the center have been investigated.
The nonlinear partial differential equations of shallow shell were reduced to the nonlinear integral-differential equations
by using the method of Green’s function. To solve the integral-differential equations, the expansion method was used to obtain
Green’s function. Then the integral-differential equations were reduced to the form with a degenerate core by expanding Green’s
function as a series of characteristic function. Therefore, the integral-differential equations became nonlinear ordinary
differential equations with regard to time. The amplitude-frequency relation, with respect to the natural frequency of the
lowest order and the amplitude-frequency response under harmonic force, were obtained by considering single mode vibration.
As a numerical example, nonlinear free and forced vibration phenomena of shallow spherical shells with sinusoidal corrugation
were studied. The obtained solutions are available for reference to the design of corrugated shells. 相似文献
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775.
《随机分析与应用》2013,31(6):1511-1523
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The present paper studies the flow and heat transfer of the hybrid nanofluids flows induced by a permeable power-law stretching/shrinking surface modulated orthogonal surface shear. The governing partial differential equations were converted into non-linear ordinary differential equations by using proper similarity transformations. These equations were then solved applying a numerical technique, namely bvp4c solver in MATLAB. Results of the flow field, temperature distribution, reduced skin friction coefficient and reduced Nusselt number were deduced. It was found that increasing mass flux parameter slows down the velocity and, hence, decreases the temperature. Furthermore, on enlarging the stretching parameter, the velocity and temperature increases and decreases, respectively. In addition, that the radiation parameter can effectively control the thermal boundary layer. Finally, the temperature decreases when the values of the temperature parameter increases. We apply similarity transformation in order to transform the governing model into a system of ODEs (ordinary differential equations). Numerical solutions for particular values of involved parameters are in very good agreement with previous calculations. The most important and interesting result of this paper is that for both the cases of shrinking and stretching sheet flows exhibit dual solutions in some intervals of the shrinking and stretching parameter. In spite of numerous published papers on the flow and heat transfer over a permeable stretching/shrinking surface in nanofluids and hybrid nanofluids, none of the researchers studied the present problem. Therefore, we believe that the results of the present paper are new, and have many industrial applications. 相似文献
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El-Sayed R. Negeed S. Hidaka M. Kohno Y. Takata 《International Journal of Heat and Fluid Flow》2011,32(1):95-106
The main objective of this research is to study analytically and experimentally the liquid sheet breakup of a flat fan jet nozzle resulting from pressure-swirling. In this study the effects of nozzle shape and spray pressure on the liquid sheet characteristics were investigated for four nozzles with different exit widths (1.0, 1.5, 2.0 and 2.5 mm). The length of liquid sheet breakup, liquid sheet velocity and the size of formed droplets were measured by a digital high speed camera. The breakup characteristics of plane liquid sheets in atmosphere are analytically investigated by means of linear and nonlinear hydrodynamic instability analyses. The liquid sheet breakup process was studied for initial sinuous and also varicose modes of disturbance. The results presented the effect of the nozzle width and the spray pressure on the breakup length and also on the size of the formed droplets. Comparing the experimental results with the theoretical ones for all the four types of nozzles, gives a good agreement with difference ranges from 4% to 12%. Also, the comparison between the obtained results and the results due to others shows a good agreement with difference ranged from 5% to 16%. Empirical correlations have been deduced describing the relation between the liquid sheet breakup characteristics and affecting parameters; liquid sheet Reynolds number, Weber number and the nozzle width. 相似文献