the following research results were obtained for the supersonic blunt body,the plasma layer of peak electron number density N_e=10~(11)～5×10~(14)/cm~3 can be formed under the condition of total temperature of the jet T0j=2000-3000K and the mass fraction of 0.02 and 0.05 for kalium,and the drag force coefficient of 35% is decreased.
Two-dimensional numerical simulation with a given temperature field and negative buoyancy indicates that:(1) the mantle convection drag force plays an important control role to subducted depth and subducted rate. Its change from 100 MPa to 20 MPa results in decreases of the subducted depth from 231 km to 151 km and subducted rate from 10.79 mm/a to 5.46 mm/a;
The synergy of gas-solid two-phase flow is showed by the ratio of drag force coefficient, CD/CDs<1.0. The synergy in the gas-solid two-phase flow system could be considered as the results of energy transfer and momentum transfer between gas phase and solid phase in which the energy consumption approaches the minimum.
Meanwhile, the drag force coefficients change with the angle. The drag force coefficients get the smallest value when the angle is 20° ,the projective area becomes larger at the same time, so the drag forces show a growing tendency.
The drag force and the filtration efficiency are determined both as functions of the ratio between the cylinder diameter and the distance between the axes of adjacent cylinders and as functions of the thickness and permeability of the shells.
The approximation formula for the drag force of a cylinder in contacting rows is obtained.
The drag force of a cylinder for this model is close to that for the fan model filter.
The expression is derived for the dimensionless drag force acting on the unit chain length as a function of the ratio of a particle radius to a half-distance between chain axes, a/h.
It is also shown that, at a/h = 1, the drag force of a particle contacting with four adjacent particles in the layer with square packing is equal to F = 44FSt, where FSt is the Stokes drag force of a spherical particle.