It is possible that differences in pressure, not evaluated in the experiments, play an important role in the evaluation of the drag from velocity profiles. High pressure values could reduce the drag; for this reason, pressure measurements are required in future experiments. To better understand the...
This might be attributed to a claim made by [17] that the presence of a favorable pressure gradient in duct flows tends to make Π smaller when compared with flat plate boundary layer flows. Hence, the logarithmic law may be valid much closer to the line of symmetry of the flow in the...
Using this, and rearranging the formula for dynamic pressure to isolate for flow velocity, the flow velocity can be determined as a function of stagnation pressure and static pressure, as shown: Where pt is the stagnation pressure (total pressure) and ps is the static pressure. This shows ...
For the movement of gas bubbles, the constant drag force is used throughout the domain, which represents spherical bubble dynamics in the experimental study. The momentum transfer equation describes stress, gradient pressure, gravity, and the exchange of the range of motion between a dispersed and...
10.The results show that the deposition rate is related to the working pressure at a given power density.在功率密度一定时,沉积速率和工作气压有关. 11.INFLUENCE OF CARRIER GAS ON THE DEPOSITION RATE OF SYNTHETIC SILICA GLASS BY CHEMICAL VAPOR DEPOSITION METHOD载料气体对化学气相沉积合成石英玻璃沉积...
Pressure-based velocity measurements (Sect. 5.1), thermal anemometry (Sect. 5.2), and particle-based techniques (Sect. 5.3) represent the latter. In addition, particle image velocimetry (PIV, Sect. 5.3.2), planar Doppler velocimetry (Sect. 5.3.3), and molecular tagging velocimetry (Sect. 5.4...
(Laws of flow in rough pipes, 1933), but the mechanism is not clear and no theoretical formulae are available to express these deviations. A Laser Doppler Velocimetry system was used to measure velocity profiles at the centre of the channel. The data obtained support previous conclusions that ...
A simple correction formula for this purpose is the Karman-Tsien formula which uses the “tangent gas” approximation to simplify the compressible potential-flow equations. Accordingto this formula, the effect of Mach number on the pressure coefficient is estimated from (10.4.2)cp=cpiβ+[M∞2/...
For general cases, the unsteady heat release is given as: (7.195)Q′=Kuu1′x=L1+Kpp1′x=L1, where L1 is the length of the region 1. This equation denotes that the unsteady heat release is induced by axial velocity or pressure disturbances in region 1 at the place of the flame. In...
if Pcc is the surplus pressure, then θ=Kn (1.7+0.1(Pcc/Pa+1)). Using this formula, according to an embodiment in which the coefficient Kn is in the range of between about 0.6-0.75 and in which the absolute combustion pressure Pcc=0.9 MPa, the expansion ratio θ may be in the range...