this research includes both experimental and cfd investigation in the hydrodynamic behavior of a new type of column tray introduced as “concap” tray. the proposed column tray is used in contactor columns especially in stripping columns. the hydrodynamics of this concap tray is investigated in a 1.2m in diameter column. using air-water system, the experiments were performed for different liquid ...

Alumina-supported manganese catalysts with cryptomelane and/or birnessite structure have been prepared using a simple method based on the thermal decomposition of potassium permanganate. The samples have been characterized by XRD, FTIR, TGA, DSC, N2 adsorption at −196 °C, SEM, H2-TPR and XPS, and their catalytic activity for soot combustion has been tested and compared to that of a reference Pt...

The present study aimed at assessing a novel annular-ducted fan lift system for VTOL aircraft through computational fluid dynamics (CFD) simulations. The power and lift efficiency of the lift fan system in hover mode, the lift and drag in transition mode, the drag and flight speed of the aircraft in cruise mode and the pneumatic coupling of the tip turbine and jet exhaust were studied. The resu...

A CFD-based numerical model has been developed for the determination of the volume concentration and number density of soot in a laminar diffusion flame of methane in air, under transient condition following ignition of the flame. The transience is studied from the point of ignition till the final steady state is reached. The burner is an axi-symmetric co-flowing one with the fuel issuing throu...

We present simulations of a laboratory-scale low swirl burner fueled with hydrogen at atmospheric pressure. The study uses detailed chemistry and transport including a submechanism for computing nitrogen emissions. The simulation shows how the cellular burning structures characteristic of lean premixed hydrogen combustion lead to enhancements in the NOx emissions from these flames. Analysis of ...

The lEC 534-8-4:1994 method of predicting audible noise external to a control valve (and inpipe noise levels) relies on the use of experimentally derived "valve specific" input parameters. This paper shows how Computational Fluid Dynamics (CFD) can be used as a too! to obtain these valve specific parameters w/ithout the need for experiment. Three types of 100mm throttling devices are modelled u...

In this research, the spray combustion, soot formation and exhaust emissions of diesel, biodiesel, gasoline fuels their mixtures are analysed in a constant volume chamber. A multicomponent kinetic mechanism (CDBG) suitable for diesel-biodiesel-gasoline developed by our research group is utilised, associated physicochemical properties thoroughly calculated. Adaptive mesh refinement scheme with a...

Engines equipped with camless valve trains will have greater space for performance optimization. In this paper, based on the electromagnetic actuated valve train system, one-dimensional and three-dimensional simulation models on engine thermodynamic cycle and in-cylinder charge motion are established, respectively. With the application of early-intake-valve closing (EIVC) strategy，unthrottled l...