in this paper, the effect of bioethanol- gasoline fuel blends on exhaust emissions of a four-cylinder spark ignition (si) engine was investigated experimentally. pure gasoline fuel was blended with various percentages of bioethanol (0, 20, 40, 60 and 85%), and the hc, co, co2 and nox exhaust emissions were measured at different engine speeds and two throttle valve positions (full throttle and 5...

Crossed Fe2O3 nanosheets supported cobalt oxide nanoparticles on three-dimensionally macroporous nickel foam substrate (xCo/Fe-NF) was designed and successfully prepared through a facile hydrothermal and impregnation route. These catalysts showed high catalytic soot combustion activities under self-capture contact mode. The three-dimensional macroporous structures of Ni foam and the crossed Fe2...

Hydraulic Pump sumps are designed to provide a swirl free flow to the pump. The degree of swirl is measured in physical model tests using a swirl meter and a quantity known as swirl angle is generally measured. The present paper presents a novel method to compute the bulk swirl angle using the local velocity field obtained from computational fluid dynamics data. The basis for the present method...

The present work is a study of the gas-flow phenomenon known as the ?end of the vortex? (EoV), which spontaneously occurs at the lower end, or under, reverse-flow centrifugal separators such as cyclones or swirl tubes. Different CFD models of swirl tubes have been built to study and analyse this phenomenon in detail. The present numerical work is based on ? and compared with ? previous experime...

Labyrinth seal force estimates are important to the prediction of the stability of turbomachinery. The force prediction methods fall into several categories: experiments, bulk flow analysis, and finite volume analysis. Finite volume analysis can be split into two subcategories: selfdeveloped and commercial. In this research, a commercial computational fluid dynamics (CFD) program called ANSYSCF...

A 1arge-scale tumble rather than swirl would exist in cylinders in the case of two valves’ opening in a fourvalve engine. A strong swirl is generated when one valve is closed, yet the flow capacity is less than that of two valves being opened. In order to change it, different lifts of valves (DLV) present are achieved. In the case of using different lifts of two intake valves, both tumble and s...

ABSTRACT An axisymmetric, turbulent, multigrid computational fluid dynamics (CFD) code is used, on a parallel computing facility, to predict the mixing between superposed flows in a pre−swirl rotor−stator system, being a simplified representation of the internal air cooling system in gas turbine engines. Strong recirculations formed by the pre−swirl cross−flow lead to entrainment of disc−coolin...

In this work, several nanostructured ceria catalysts were prepared by means of a hydrothermal procedure, in which the synthesis conditions (i.e., temperature and pH values) were varied. CeO2 samples of different shapes and structural properties were obtained, namely cubes, rods, cube and nanorod mixtures, and other polyhedra. The prepared materials were tested using four probe catalytic reactio...