ANSYS Workbench fluid flow(fluent) Tutorial,Open Channel Flow in a Pipe

Computational Fluid Dynamics(CFD),A basic Fundamental.

CFD- computational fluid dynamics is one  the best method to assume the flow physics.Basically the fluid flow problems are governed by the conservation principle of mass,momentum and energy. These conservation principles get expressed in terms of mathematical equations.These mathematical equations involves a set of non-linear partial differential equations(PDE).The main problem arise here ,the fact is :-there are no generic theories available to solve these PDEs.

 Here comes the role of CFD, Before going into CFD concept,one must understand what is CFD ? CFD is nothing but the analysis of systems that involves fluid flow ,heat and mass transfer ,chemical reactions by help of computer based simulation. It is basically a computer based solving process by help of some algorithms.


All CFD codes basically contains 3 main elements:

    1) Pre-Processor

    2) Solver

    3) Post-Processor

Pre-Processor:-

The preliminary step of a CFD analysis is the Pre-processing step.It involves- Defining the geometry,Mesh(grid) generation,Selection of the physical and chemical phenomena that to be modelled, Defining the material properties,specifying the appropriate boundary conditions,etc.
Before proceeding to this one should have a brief idea of the physical problem which has been chosen.

Solver:-

CFD uses some solver to solve these numerical problems, there are generally three numerical solution methods.

 1) Finite Difference Method (FDM)

 2) Finite Volume Method (FVM)

 3) Spectral Methods

ANSYS Fluent solver uses Finite volume method to solve the computational problems.


How Does the numerical algorithm in CFD works?

 1)Integration of the governing equations of fluid flow over all the elements/control volumes of the domain.Then converting the resultant integral equations into a system of algebraic equations.Then the solver uses iteration technique to solve by taking some initial guess.There are various algorithm used by CFD solver these are : SIMPLE,SIMPLER,SIMPLEC,PISO etc. All these algorithms will be discussed in the future.

Post-Processing:-

The post processing part of a computational problem involves the output of the simulation results these are :-Contours,Streamlines,Temperature plots,Grid display,2D and 3D surface plots,Particle tracing,Animations etc.

Ansys Tutorial:Flow in a Helical Pipe

ANSYS tutorial,Flow in a u-bend pipe(circular cross-section)

ANSYS WORKBENCH Tutorial,Flow inside a U-bend pipe(Rectangular Cross-section)

How to create a geometry in ANSYS, Geometry:-Cone

Deflection due to self-weight,a comparision between Prismatic bar and Conical bar

As per the basic Mechanics of solid, a conical bar having same specific weight as a prismatic bar^* will experience less deflection due to self-weight. And the deflection of the prismatic bar will be 3 times more than the deflection of a conical bar. To illustrate this concept, an ANSYS Static structural tutorial has been made, to show that how we can solve and find the amount of deflection by using “FINITE ELEMENT METHOD” ,in this current tutorial, three bars has been taken, two are prismatic and one is conical, all the three have the same volume, the sides of the square cross-section and radius of the cone base has been found out by equating the volume. The material of the bars is Stainless Steel, fixed at one end. Standard acceleration due to gravity has been considered to add weight to these bars.

RESULT AND DISCUSSION:

From the ANSYS static structural simulation, it has been found that: The deflection due to self-weight in prismatic bars is same for circular as well as Square cross-section bar, whereas in case of conical bar the deflection is less (i,e 1/3rd that of Prismatic bar).

*What is a Prismatic bar?

Bar having same cross-section throughout its length

ANSYS Workbench, Mechanical Static Structural Tutorial:-Deflection due to self-weight (Different Material)

ANSYS fluent Tutorial:-Three dimensional(3D) Laminar Pipe Flow