Result and Discussion In the plot of an Elliptical the Grid lines have been

Result and discussion in the plot of an elliptical

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Result and Discussion In the plot of an Elliptical, the Grid lines have been smoothed out due to the elliptic equations, eliminating extreme jaggedness resulting from the algebraic grid. This would ensure a more accurate flow model. Enter the number of grid points in the i direction: 50 Enter the number of grid points in the j direction: 50 The solution took 2434 iterations to converge. Elliptic grid over an Airfoil Overall, an elliptic grid was shown to provide desired results for discretization. It succeeded in smoothing out otherwise rough edges created through algebraic grid generation. At the same time, the algebraic grid provided a suitable starting point for the generation of the elliptic grid. 0 0.5 1 1.5 x 2 2.5 3
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Dept of ANE CA Lab Manual MRCET 18 EXPERIMENT 5 FLOW OVER AN AEROFOIL Aim: To simulate flow over NACA 0012 airfoil and find pressure velocity distribution over airfoil. Problem description : Consider air flowing over NACA 0012 airfoil. The free stream velocity is 90 m/s Assume standard sea-level values for the free stream properties: Pressure = 101,325 Pa Density = 1.2250 kg/m 3 Temperature = 288.16 K Kinematic viscosity v = 1.4607e-5 m 2 /s Software: ICEM and CFX Steps Involved In ICEM 1) Creation of Geometry in ICEM CFD: Importing the Aerofoil coordinates File →Import Geometry→Formatted point data→Select the file of aerofoil coordinates which is in DAT format→ok. Now the coordinates will be displayed. Geometry→Create/modify curve→From points→Select above points and leave last 2 points→middle click Similarly on bottom side Join the end points of the curves Create a point in z direction using Geometry →create point→Explicit coordinate→x=0,y=0,z=1→Apply. Join points (0,0,0) and (0,0,1) using create/modify curves→from points. Create/Modify surfaces→curven driven→driving select curve along z axis →driven curves select airfoil→Apply 2) Creation of Domain: Geometry →Create/Modify surface →Satndard shapes→Box→X Y Z = 7 2 1→Origin= -3 -1 0 →Apply Geometry →Create/Modify surface →Segment/Trim surface →Select surface →side walls of box →Select curves → airfoil curves →Apply Create Body→Part:body→Material point→Location→centroid of 2 points→2 screen location→select 2 points in box such that its center will be above or below
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Dept of ANE CA Lab Manual MRCET 19 airfoil→Apply 3) Creation of parts: Parts in the tree→Righ t click→Create part Part Suction Select entity airfoil upper surface Part: Pressure Select entity airfoil lower surface Part: TE Select entity airfoil rear surface Part : Inlet→ Select entity box front face Part : Outlet→Select entity box back face Part: Walls→ Select entity remaining box walls 4) Generation of Mesh: Mesh→Global M esh setup Max Element size:1 Curvature?Proximity Based Refinement →Enabled→Min size: 0.01 →Apply. Part Mesh Setup Inlet→Maximum size : 0.2 Outlet→Maximum size: 0.2 Walls→Maximum size: 0.2
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Dept of ANE CA Lab Manual MRCET 20 Suction and Pressure→Maximum size:0.05
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  • Spring '18
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