Gas holdup is one of the most important hydrodynamic parameters needed for reliable design, performance estimation, and scale-up of stirred tank reactors (STRs). In the present work, local gas holdup is measured in an acrylic stirred tank reactor equipped with a Rushton impeller using X-ray computed tomography (CT) for many different operating conditions. Power consumption for different operati...

In this paper, the reasons of damage water pumps parts of the air compressor cooling system were studied. To reach this goal, the works like preparing metallographic samples, evaluation of structure, investigation of mechanical properties, the alloy parts detection and chemical analysis of deposit and corrosion products collected from the parts were performed. According to studies and results o...

High-pressure air enters the air-turbine of the dental handpiece and strikes the blades to drive the impeller. The air-turbine has impeller and the air tube is connected to the air-turbine housing. The flowfield of the air-turbine were investigated for the optimum air-turbine design using ANSYS CFX. The objective of the research was to find an optimum design variables for the air-turbine to inc...

Results of numerical simulations of momentum transfer for a highly shear-thinning fluid (0.2% Carbopol) in a stirred tank equipped with a Prochem Maxflo T type impeller are presented. The simulation results were validated using LDA data and both tangential and axial force measurements in the laminar and early transitional flow range. A good agreement between the predicted and experimental resul...

Centrifugal pumps are extensively used to transfer liquids to the required head with the help of centrifugal forces. The impeller forms the crucial part of the centrifugal pumps. Its shapes, dimensions, number of the blades affects the overall performance of the pumps.In this paper, effect of number of blades in the impellers are investigated using CFD tool. Considering the number of blades in ...

The VentrAssist implantable rotary blood pump (IRBP) is a centrifugal pump that uses a hydrodynamic bearing to support its impeller. The pump is to be used as a left ventricular assist device (LVAD). Varying pump speed can control the degree of left ventricular assistance. By increasing impeller speed, it is possible to transition from the normal physiological state of ventricular ejection (VE)...

The circularly polarized reflection of nature is due to their distinct azimuthally twisted or helical character in the nanostructure of the surface films. Although many chiral inorganic powders have been successfully synthesised, the artificial synthesis of chiral inorganic films is rare. Herein, we reported a facile synthetic route for the growth of monolayered chiral film on the quaternary am...

BACKGROUND Turbulence intensity, or hydromechanical stress, is a parameter that influences a broad range of processes in the fields of chemical engineering and biotechnology. Fermentation processes are often characterized by high agitation and aeration intensity resulting in high gas void fractions of up to 20% in large scale reactors. Very little experimental data on hydromechanical stress for...

Cavitation is one of the most well-known process faults that may occur in different industrial equipment especially centrifugal pumps. Cavitation also may happen in water pumps and turbines. Sometimes cavitation has been severe enough to wear holes in the impeller and damage the vanes to such a degree that the impeller becomes very ineffective. More commonly, the pump efficiency will decrease s...

In this paper A Geometrical Design Method for Blade’s surface I in the impeller is provided here I is a solution to a coupling system consisting of the well-known Navier-Stokes equations and a four order elliptic boundary value problem . The coupling system is used to describe the relations between solutions of Navier-Stokes equations and the geometry of the domain occupied by fluids, and also ...