Analysis of Fluid Flow over Two Balls using Ansys Software CFD

ABSTRACT
The project report deals with the analysis of the compare the fluid flow over the
two ball (Golf and Normal) at different conditions, using the Ansys Software CFD
part. In the starting design two ball diameter 42.67mm using solid works
software. Condition for the ball study here is 30 to 600 m/s at different Reynolds
number. On these simulation is done by using ANSYS 18.1. Fluent workbench is
used to do the simulation work. CFD to obtain and compare drag force between
two geometries (golf ball and normal sphere of the same size) using Ansys
Fluent. Here in this project we have disvuss turbulence, discretisation order, and
material properties affecting this comparison in your assignment. The value of
the drag force obtained based on the Reynolds Number, speed and
environmental conditions. Comparison is done in the tabular form. It is showing
the relation between Reynolds number, velocity of fluid and material properties.

There are some basic theory needed to understand the problem where we can
go directly for the concept, and why this terminology used here.
Newtonian fluid
That ratio between the stress and strain where we plot the graph it gives linear
value from origin. This behavior of the fluid is known as Newtonian fluid.
mathmatically is
Where Ꚍ= shear stress (drag) pascal
μ = fluid viscosity
du/dy = strain rate , velocity gradient perpendicular to the shear direction
Non-Newtonian fluid
It is different from the Newtonian fluids, mostly commonly depends on the
viscosity of non Newtonian fluids. It does not depend over the shear rate. If we
will draw a plot between the shear rate it becomes is different. (Anderson,2011)
Computational fluid dynamics
Computational fluid dynamics is a branch of the ANSYS. It is wide play role for
the fluid flow and aerodynamic testing. Before CFD testing was done by the
practical prototype of the part or Assembly. There was too much time and spent
the money. But after using CFD we can do very easily without the prototype and
or any wind tunnel testing. There is lot of saving the time and resources, here
we can modify the value and reuse the same part for the testing/ analysis.
Using the boundary condition, we can go through the material property and
high accuracy of the results. it gives better solutions.
ANSYS, Inc.
It is solver application and used to solve the equation and flow simulation. we
can get the accuracy near to practical testing value. Ansys have many branch in
engineering, for example static structural, fluent, CFX, CFD, Ls- Dyna, Modal

Analysis, Harmonic
analysis........ etc. In
this bracnhes we are
discussing about the
fluent, where we study
about the Flow over
the ball at different
value of speed.
Drag coefficient
Drag, it is a term used
in the part of
Aerodynamic forces.
When flow pass
through the
body surface, there
some oppose force
comes between flow
and body. This force is
called Drag force; in
this we used one
dimensionless
coefficient. It is called
drag coefficient. Cd.
(Anderson, 2009)
TABLE 3
Model (A3, B3, C3) >
Geometry > Parts
The problem
statement
Here we have case
study of the ball and
golf ball behavior at
the different speed.
We have three type of
speed 30, 300, 600
m/s. in this speed we
are trying to check
Object Name
Mesh
State Solved
Display
Display Style Body Color
Defaults
Physics Preference CFD
Solver Preference Fluent
Relevance 100
Export Format Standard
Element Order Linear
Sizing
Size Function Curvature
Relevance Center Medium
Transition Slow
Span Angle Center Fine
Curvature Normal Angle Default (12.0 °)
Min Size Default (1.449e-002
mm)
Max Face Size Default (1.4490 mm)
Max Tet Size Default (2.8980 mm)
Growth Rate Default (1.10 )
Automatic Mesh Based
Defeaturing On
Defeature Size Default (7.245e-003
mm)
Minimum Edge Length 50.0 mm
Quality
Check Mesh Quality Yes, Errors
Target Skewness Default (0.900000)
Smoothing Medium
Mesh Metric None
Inflation
Use Automatic Inflation None
Inflation Option Smooth Transition
Transition Ratio 0.272
Maximum Layers 5
Growth Rate 1.2
Inflation Algorithm Pre
View Advanced Options No
Assembly Meshing
Method None
Advanced
Number of CPUs for Parallel Part
Meshing Program Controlled
Straight Sided Elements
Number of Retries 0
Rigid Body Behavior Dimensionally
Reduced
Mesh Morphing Disabled
Triangle Surface Mesher Program Controlled
Topology Checking No
Pinch Tolerance Default (1.3041e-002
Object Name Solid
State Meshed
Graphics Properties
Visible Yes
Transparency 1
Definition
Suppressed No
Coordinate
System Default Coordinate System
Behavior None
Reference Frame Lagrangian
Material
Assignment
Fluid/Solid Fluid
Bounding Box
Length X 60. mm
Length Y 50. mm
Length Z 50. mm
Properties
Volume 1.4967e+005 mm³
Centroid X 5.2057e-019 mm
Centroid Y -1.1769e-016 mm
Centroid Z 5.1335e-019 mm
Statistics
Nodes 47029
Elements 254424
Mesh Metric None

their turbulence, speed effect and some more parameter as we can see details
given below:
Ball Parameter;
Table 2. Mesh Information for FFF
Doma
in
Nod
es
Eleme
nts
solid 4702
9
254424
TABLE 5
Model (A3, B3, C3) > Mesh
Table 4. Boundary Physics for FFF
Domain Boundaries
solid Boundary - ball
Type WALL
Boundary - inlet1
Type VELOCITY-INLET
Boundary - outlet1
Type PRESSURE-OUTLET
Boundary - wall
Type WALL