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351.
In the use of underground space for storage of solar energy, storage of excess heat from thermal power plants and containment of nuclear waste, the host medium is subjected to a thermal field accompanied by a thermal stress field. These stresses may endanger the stability and integrity of the structure. In this paper, the stress field, in circular and spherical openings, due to a given thermal field is analytically determined and numerically verified. Both lined and unlined openings are considered. The numerical and analytical results are in a satisfactory agreement. The lining stresses, support pressure and radial interface displacement depend only on the thermal field in the lining. A simplified method of stress computation applicable to a thin lining is also presented. 相似文献
352.
The effect of radiation up on the state of gas behind strong M.H.D. shock front has been studied. The jump conditions for flow variables across the shock boundary have been obtained and temperature decay behind the shock front is determined for a optically-thin brehmsstrahlung radiation plasma. It has been found that, for a shock within strong magnetic field, the temperature decay is much quicker. 相似文献
353.
Solutions of Brans-Dicke field equations in Dicke's conformally-transformed units are obtained when the source of the gravitational field is that of charged perfect fluid where the line element taken is that of Roberton-Walker. 相似文献
354.
The problem of an axially-symmetric viscous fluid interacting with the gravitational field has been investigated. Exact solutions have been obtained for the pressure and density of the viscous fluid. Physical interpretation of the solutions in respect of the expansion factor, acceleration components reality conditions of the distribution, etc., have been made. 相似文献
355.
Self-similar flows of a perfect gas behind the cylindrical shock wave propagating exponentially in an atmosphere whose density varies inversely as the fourth power of shock radius are investigated. The effects of radiation flux has also been taken into consideration. The total energy of the wave is constant. 相似文献
356.
A. K. Singh 《Astrophysics and Space Science》1984,105(2):307-313
In this work we present the two-dimensional free-convective flow of an elastico-viscous fluid past an infinite vertical porous plate for the Stokes problem when the flow is subjected to a constant suction velocity through the porous plate. As the mean steady flow has been presented in Part I, obly the solution for the transient velocity profiles, transient temperature profiles, the amplitude and the phase of the skin-friction and the rate of heat transfer are presented in this work. As in the case of mean steady flow, the influence of the various parameters on the unsteady flow field is discussed for both the cases cooling and heating of the porous plate by free-convection currents. 相似文献
357.
Two gamma ray source fields CG 189+1 and CG 075+00, centered on the corresponding UHURU Point X-ray source positions, were observed with the IPC onboard Einstein Observatory. An unidentified weak X-ray source is detected from the direction of CG 189+1 only. 相似文献
358.
The Meixner functions are utilized to relate the effective rainfall, the direct runoff and the unit hydrograph through linkage equations. The linkage equations are then employed to derive the unit hydrograph for given rainfall-runoff data on a small agricultural watershed. These functions are tested with regard to their ability to reproduce and predict the direct runoff hydrograph. The Meixner functions are found to be an effective analytical tool for hydrograph synthesis. Further, they compare well with the least squares and linear programming methods of the unit hydrograph derivation. 相似文献
359.
The equilibrium structure and oscillations of a partially degenerate standard model in the presence of a poloidal magnetic field have been studied. The magnetic field in the interior has been matched with an outside dipole field. The effect of magnetic field on the various structural parameters, e.g., mass, central condensation, moment of inertia, and oblateness has been computed for different values of the central degeneracy of the model. We have also studied the effect of magnetic field on radial oscillations of the configuration. A variational formulation is used to compute the changes in the frequency of radial mode of oscillation. It has been shown that the changes in frequency computed for various models using a two-parameter eigenfunction are in fair agreement with the values obtained by using the exact eigenfunction. 相似文献
360.
The equilibrium of a self-gravitating fluid spheroid is examined in the presence of a rotation and a poloidal magnetic field. It is shown that ‘true equilibrium’ allows only rigid rotation for a spheroid of a small eccentricity. 相似文献