Analytical solution of flow field for weak Mach reflection over plane surface

Shock Waves ◽  
2005 ◽  
pp. 467-472 ◽  
Author(s):  
A. Sakurai ◽  
F. Takayama
Author(s):  
Yasuhiro Aida ◽  
Koichi Masuda ◽  
Tomoki Ikoma ◽  
Hiroaki Eto

Abstract One of the reasonable methods to analyze the collision force of a tsunami drifting object against a structure is a particle method. However, when both the structure and the drifting body are composed of particles, there are various problems such as particles of the collision object slipping through particles of the structure. Therefore, the authors have constructed a particle method - analytical solution hybrid method which can analyze the collision force of a tsunami drifting object to an elastic member by constructing a structure as a boundary condition acting on a drifting object. However, since this boundary was introduced as a virtual boundary that acts only on drifting particles, the collision force of the tsunami drifting object to the structure can be analyzed, but the fluid force can’t be analyzed. Therefore, in this study, in addition to the boundary condition as the structure, we further reconstructed the collision force and the fluid force as a method that can analyze the collision force and the fluid force simultaneously by setting the mirror particle boundary condition for the fluid particle. By developing this method, it became possible to calculate the collision force in a situation where a stagnation point occurs like a flow field at the front of the wall type structure, and the drifting object is decelerating.


2015 ◽  
Vol 7 (3) ◽  
pp. 295-322 ◽  
Author(s):  
Valeria Boccardo ◽  
Eduardo Godoy ◽  
Mario Durán

AbstractThis paper presents an efficient method to calculate the displacement and stress fields in an isotropic elastic half-space having a hemispherical pit and being subject to gravity. The method is semi-analytical and takes advantage of the axisymmetry of the problem. The Boussinesq potentials are used to obtain an analytical solution in series form, which satisfies the equilibrium equations of elastostatics, traction-free boundary conditions on the infinite plane surface and decaying conditions at infinity. The boundary conditions on the free surface of the pit are then imposed numerically, by minimising a quadratic functional of surface elastic energy. The minimisation yields a symmetric and positive definite linear system of equations for the coefficients of the series, whose particular block structure allows its solution in an efficient and robust way. The convergence of the series is verified and the obtained semi-analytical solution is then evaluated, providing numerical results. The method is validated by comparing the semi-analytical solution with the numerical results obtained using a commercial finite element software.


2003 ◽  
Vol 125 (2) ◽  
pp. 339-344 ◽  
Author(s):  
Mohammad I. Kilani ◽  
Paul C. Galambos ◽  
Yousef S. Haik ◽  
Ching-Jen Chen

A new viscous spiral micropump which uses the surface micromachining technology is introduced. The paper outlines the design of a spiral pump fabricated in five levels of polysilicon using Sandia’s Ultraplanar Multilevel MEMS Technology (SUMMiT), and presents an analytical solution of the flow field in its spiral channel. The pump characteristics are obtained experimentally for a scaled-up prototype and are found to be in good agreement with the results obtained using the analytical model.


2015 ◽  
pp. 1-13
Author(s):  
H.-Y. Wang ◽  
X.-W. Tang ◽  
Y. Wang ◽  
Q. Tang ◽  
P.-L. Gan

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Xiaoqiang Fan ◽  
Yuan Tao

Experimental results show that there exist two flow fields in the hypersonic inlets when the forebody waves interact with the lip boundary, which is similar to the shock reflection ion hysteresis phenomenon. In order to improve the performance of the flow field, counterflow is applied to control the shock reflection configuration in the hypersonic inlets. For better understanding of the internal mechanism, inviscid numerical simulation is conducted. And the results demonstrate that it is feasible to realize the transition between the regular reflection configuration and the Mach reflection ion configuration in the hypersonic inlets. That is because the von Neumann criterion and detached criterion play a dominant role, respectively, in these transitions. In addition, the evolution process of Mach reflection ion in the hypersonic inlets can be divided into three stages: transmission of waves, emergence of Mach stem, and stabilization of flow field.


AIAA Journal ◽  
1980 ◽  
Vol 18 (9) ◽  
pp. 1036-1043 ◽  
Author(s):  
G. Ben-Dor

Sign in / Sign up

Export Citation Format

Share Document