Computational fluid dynamics or CFD

What is the meaning of computational fluid dynamics?

A branch of fluid dynamics which makes use of not only the numerical analysis but also the algorithms in order to solve as well as analyse the problems is known as computational fluid dynamics; moreover, this is inclusive of the fluid flows. Computers are generally employed to perform those set of calculations & these calculations are further required to simulate interaction of not only liquids but also that of the gases with the surfaces that are defined by the boundary conditions.

Developments

As technology has been improving day by day it is also helping people to understand as to what will be the result thus, with the use of those high – speed supercomputers, an individual will be able to achieve enhanced solutions. In addition to this, the research which is going on now suggests that when the software is being employed then there was improvement in both the speed & the accuracy of the complex simulation situations like that of the turbulent or the transonic flows. To have a better understanding of this, the initial experimental validation of a software like the one stated above is performed with the help of wind tunnel while the final validation is done keeping in mind the full – scale testing. The best example for this one would be the flight tests.

What is CFD?

Essentially, this computational fluid dynamics is also known as CFD & it provides for the most of the times qualitative & at times quantitative prediction of the fluid flows with the help of mathematical modelling, numerical methods & the software tools. Moreover with CFD by a scientist’s or an engineer’s side, they can perform the numerical experiments in a virtual flow laboratory.

Why should computational fluid dynamics be used?

As a matter of fact, CFD or the computational fluid dynamics is used for the numerical simulations of fluid flow for the following aspects – (1) enable the architects to design some comfortable & the safe living environments (2) chemical engineers can maximize yield from the equipment (3) surgeons can cure the arterial diseases (4) vehicle designers will be able to improve aerodynamic characteristics (5) petroleum engineers can devise the optimal oil recovery strategies (6) military organisations can have the weapons developed apart from estimating the change (7) health risks from radiation & the other hazards can be reduced by the safety experts & (8) the meteorologists will be in a position to forecast weather besides warning people of the natural disasters.

Methodology of CFD

The methodology of CFD is preprocessing, discretion, finite volume / element / difference, spectral element & the boundary element method.

Formulae / equations related to computational fluid dynamics

Finite volume equation

\frac{\pa}{\pa t} \iiint {Q\,dV}+\iint{F\,dA}\,=\,0

Weighted residual equation

R_i\,=\, \iiint {W_iQ\,dV^e}

Finite difference equation

\frac{\pa Q}{\pa t}+\frac{\pa F}{\pa x}+\frac{\pa G}{\pa y}+\frac{\pa H}{\pa z}=0

In the above equations, Q= vector of conserved variables,  F,G,H= fluxes  x,y,z= directions, R_i = equation residential at element vertex,i ; W_i = weight factor, V^e = element’s volume,  V= control volume element’s volume & A = surface area of control volume element.