Wyniki wyszukiwania - BazTech

1

Vishwakarma J. P., Pathak P.

International Journal of Applied Mechanics and Engineering

|

2012

|

Vol. 17, no. 2

603-619

EN

Similarity solutions are obtained for an adiabatic flow behind a magnetogasdynamic cylindrical shock wave propagating in a rotational axisymmetric flow of a perfect gas in the presence of a variable azimuthal magnetic field. The initial medium is considered to have a variable density and a variable azimuthal velocity component in addition to a variable axial velocity. Initial velocities, density and the magnetic field are assumed to obey power laws. Distributions of the fluid velocities, density, pressure, magnetic field and vorticity components are obtained in the flow-field behind the shock front. Effects of an increase in the value of the index for variation of an ambient azimuthal magnetic field, in the value of the index for ambient density and in the strength of the initial magnetic field are obtained. It is found that the presence of the magnetic field has a decaying effect on the shock wave.

2

Propagation of spherical shock waves in a dusty gas with radiation heat-flux

Singh K. K., Vishwakarma J. P.

Journal of Theoretical and Applied Mechanics

|

2007

|

Vol. 45 nr 4

801-817

EN

The propagation of spherical shock waves in a dusty gas with radiation heat-flux and exponentially varying density is investigated in the paper. The equilibrium flow conditions are assumed to be maintained, and the radiation is considered to be of a diffusion type for an optically thick grey gas model. The shock wave moves wit h variable velocity and the total energy of the wave is non-constant. Non-similar solutions are obtained, and the effects of variation of the radiation parameter and time are investigated. The effects of an increase in (i) the mass concentration of solid particles in the mixture and (ii) of the ratio of the density of solid particles to the initial density of gas on the flow variables in the region behind the shock are also investigated.

PL

W pracy zajęto się problemem propagacji sferycznych fal uderzeniowych o wykładniczym rozkładzie gęstości w zanieczyszczonym gazie z uwzględnieniem radiacyjnej wymiany ciepła. Założono równowagowe warunki przepływu czynnika, a samą radiację przyjęto typu dyfuzyjnego w modelu optycznie nieprzezroczystego gazu. Fala uderzeniowa przemieszcza się ze zmienną prędkością, a całkowita energia fali również się zmienia. W analizie otrzymano rozwiązania niepodobne przy rozważaniu wpływu czasu i zmienności strumienia radiacji. Zbadano ponadto efekt wzrostu koncentracji masy cząstek stałych zanieczyszczenia oraz stosunku gęstości tych cząstek do początkowej gęstości gazu na parametry przepływu w obszarze bezpośrednio za czołem fali.

3

Converging detonation waves in a dusty gas

Vishwakarma J. P., Nath G.

Journal of Technical Physics

|

2006

|

Vol. 47, no 3

159-173

EN

The problem of converging detonation waves propagating through a dusty gas and releasing a constant amount of energy per unit mass is studied. The dusty gas is assumed to be a mixture of small solid particles and a perfect gas. The solid particles are distributed continuously in the perfect gas. An expression for the similarity exponent is determined for the detonation wave travelling in the Chapman-Jouguet regime. Also, the variation of the flow variables just behind the detonation front with the radius of the front are obtained. It is found that the presence of dust particles in the medium has a significant effect on the similarity exponent and the flow variables.