نتایج جستجو برای: well pressure
تعداد نتایج: 1874183 فیلتر نتایج به سال:
This paper is devoted to study the effects of pressure drop in heat exchangers on the dynamics of a free piston Stirling engine. First, the dynamic equations governing the pistons as well as the gas pressure equations for hot and cold spaces of the engine are extracted. Then, by substituting the obtained pressure equations into the dynamic relationships the final nonlinear dynamic equations gov...
Identifying factors which contribute to young adults’ temptation for substance use is a significant step toward prevention of this social harm. The current study aimed to examine the role of a set of personal and social factors and their interaction in shaping temptation for cigarette smoking and substance use among university students. Participants were 766 students at Shahid Beheshti Univers...
Background : Cardiovascular disease (CVD) is one of the major health problems in our country. The aim of this study is to determine the predictors of CVD risk factors in adolescents residing in distinct- 13 of Tehran . Materials and methods : Dietary intake assessment was undertaken with 2-day 24-hour recall in 420 adolescents, 11-18 years old, from a total of 15005 subjects participating in Te...
In this investigation a suitable algorithm for the detection of cracks in the pressure vessels is presented. The equations of motion for the vessel are obtained and transferred into the wavelet space in a simplified form resulted from time and position approximations. The locations of cracks are randomly distributed in different regions of the structure to cover the whole geometry of the pressu...
Determining the Hydro-acoustic Characteristics of the Ship Propeller in Uniform and Non-uniform Flow
This research has been carried out to determine the marine propeller hydro-acoustic characteristics by Reynolds-Averaged Navier-Stokes (RANS) solver in both uniform and non-uniform wake flow at different operating conditions Wake flow can cause changes in pressure fluctuation and gas effect on propeller noise spectrum. Noise is generated by the induced trailing vortex wake and induced pressure ...
This article reports the active control of base flows using the experimental procedure. Active control of base pressure helps in reducing the base drag in aerodynamic devices having suddenly expanded flows. Active control in the form of microjets having 0.5 mm radius placed at forty-five degrees apart is employed to control the base pressure. The Mach numbers of the present analysis are 1.7, 2....
The fluid flow and heat transfer in a three-dimensional microchannel filled with Al2O3- water nanofluid is numerically investigated. The hybrid scheme is used to discretize the convection terms and SIMPLER algorithm is adopted to couple the velocity and pressure field in the momentum equations. The thermal and flow fields were analyzed using different volume fractions of n...
In this study, some characteristics of a Mather type Plasma Focus (PF) device such as a discharge current, pinch time, ion flux and hard x-ray intensity has been investigated simultaneously in argon and nitrogen gases separately for various operating gas pressures and charging voltages of capacitor bank. It was observed that pinch phenomena was energy and pressure dependent in current sheath as...
The fluid flow and heat transfer in a three-dimensional microchannel filled with Al2O3- water nanofluid is numerically investigated. The hybrid scheme is used to discretize the convection terms and SIMPLER algorithm is adopted to couple the velocity and pressure field in the momentum equations. The thermal and flow fields were analyzed using different volume fractions of n...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید