As in the current industrial process, mixing is an essential process for various streams of application in engineering fields. The aim of this paper is to predict flow behaviour of the mixing process in mixing tank with the Rushton impeller and find out the best suitable design that creates required turbulence for producing a better degree of homogeneity in mixing. The rotation of the impeller is modelled using MRF in a single-phase medium treating the walls with a no-slip boundary. The mixing characteristics of single and multiple impellers are investigated by varying the impeller speeds and the results of velocity and pressure contours are compared to identify the best impeller with enhanced mixing.

This paper reports based on a numerical study of multiphase fluid flow through a channel with a semi-submersible platform using computational fluid dynamics (CFD). The present study will be designing and analysing semisubmersible platform with pencil column and without pencil column. The computational fluid dynamics which solves simple differential equations and finite volume method (FVM) will be used. A turbulence model is considered i.e. large eddy simulation (LES). The semi-submersible model is designed as pontoons, columns, horizontal brace, pencil column and deck. The pontoons are horizontal placed stadium shaped structures which are submerged into the water. The columns are structures which connects the deck and pontoons. The horizontal braces are structures which connects the two or more columns which increases the rigidity of the columns. The pencil columns are columns with lesser diameter of about 0.25D which are placed between the columns. The deck are flat surfaces which provides workable area. This paper is a comparison of fluid flow by varying the model i.e. with and without pencil column in the semi-submersible platform. The velocity contours, pressure contours and streamline contours are plotted. The difference in pressure, velocity and streamline flow are tabulated and graphically represented. The percentage difference in pressure and velocity are calculated for structural design for various offshore platforms.

As mixing is an essential operation in many engineering fields a mixing system is designed using agitated vessels in which it is difficult to obtain accurate information on induced turbulence by the impeller where CFD can provide detailed understanding of such systems. Here the impeller is designed and tested in both single phase &multiphase. Here specifically incompressible flow is used and Multiple reference frame is used to model the motion of the impeller zone. Hence, we study the flow characteristics by comparing the velocity and temperature contour of three different rotating speed of the impeller and predict the percentage increase and decrease for varying boundary conditions.