In order to study the impact of microfractures on the elastic wave velocity, multi-azimuth elastic wave velocity experiments were performed with coal rock samples under a confining pressure similar to the one in the buried coal strata of the Qinshui basin. The results indicate that (1) the microfractures in coal rock reduce the elastic wave velocity. In the experiments, the velocity was increas...

BACKGROUND The problems of patients with erectile dysfunction have been recognized, leading to the emergence of sildenafil, which has led to successful treatment in many cases. The purpose of this study is to examine the effect of sildenafil on the pulse wave velocity of patients with erectile dysfunction. METHODS Fifteen patients with erectile dysfunction were enrolled for this study. The br...

the unsteady flow in porous medium of a viscous incompressible fluid bounded by two parallel porous plates is studied with heat transfer. a uniform and constant pressure gradient is applied in the axial direction whereas a uniform suction and injection are applied in the direction normal to the plates. the two plates are kept at constant and different temperatures and the viscous dissipation is...

A predictive model for droplet size and velocity distributions of a pressure swirl atomizer has been proposed based on the maximum entropy formalism (MEF). The constraint conditions of the MEF model include the conservation laws of mass, momentum, and energy. The effects of liquid swirling strength, Weber number, gas-to-liquid axial velocity ratio and gas-to-liquid density ratio on the droplet ...

Peak systolic pulmonary valvar pressure gradients are frequently seen in large intracardiac left-to-right shunt lesions. Conventionally, this has been attributed to "relative" pulmonic stenosis. Theoretical considerations suggest that this gradient is due to differences in expression of the total fluid energy. The side pressure, the downstream pressure, the end pressure, and the flow velocity i...

We generate predictions for the fluctuating pressure field in turbulent pipe flow by reformulating the resolvent analysis of McKeon and Sharma (J. Fluid Mech., vol. 658, 2010, pp. 336–382) in terms of the so-called primitive variables. Under this analysis, the nonlinear convective terms in the Fourier-transformed Navier–Stokes equations (NSE) are treated as a forcing that is mapped to a velocit...

a numerical model is developed to simulate the transport phenomena in the flow channel between parallel plates with porous and non-porous (or impermeable) walls. the continuity and momentum equations were solved first, assuming the wall reynolds number in the range of with the suction or injection of air at a speed equal to the uniform inlet velocity. the results show that at constant inlet and...

In the present investigation the distribution of mean velocity, static pressure and total pressure are experimentally studied on an annular curved diffuser of 37.5° angle of turn with an area ratio of 1.273 at Reynolds number 1.85 x 10 based on inlet diameter and mass average inlet velocity. The experimental results then were numerically validated with the help of Fluent and then a series of pa...

OBJECTIVES We assessed the feasibility and reproducibility of the instantaneous diastolic coronary flow velocity-pressure gradient relation to characterize different degrees of coronary stenoses. BACKGROUND Assessment of the hemodynamic significance of coronary stenoses can be difficult. Using sensor-tipped guidewires, various physiologic indexes can be determined in the catheterization labor...