Computational Fluid Dynamics (CFD)--What is it?
Computational fluid dynamics, or CFD, are the methods of applying the laws of fluid mechanics and the underlying mathematical equations and principles to sophisticated computer algorithms to produce software or computer programs for visualizing data to render graphical expressions, or interpretations, of how liquids and gases interact in relation to being stored/travelling through a closed boundary—such as water in a pipe or jet fuel in an aircraft’s wing.
As a specialized branch of fluid mechanics, fluid dynamics’ overall mission is to understand and explain the physics that govern the flow of fluids such as water, oil, or ethanol. Professionals in the aerospace, mechanical engineering, aerodynamics, and civil engineering sectors commonly implement computational fluid dynamics software.
Initial and Boundary Conditions
CFD takes into account several factors that closely affect the behavior of fluids and helps to visualize them via graphical simulation. Some of these ‘factors’ include mass transfer, chemical reactions, heat flow, and changes in gas to liquid and liquid to gas phases. Furthermore, ‘initial’ and ‘boundary’ conditions contribute to the understanding of what solutions are possible. The ‘initial boundary’ is the known pressure (p) and the initial velocity (or rate of speed, or U). The boundary condition is a set of numbers based on complex equations and algorithms and, essentially, dictates the outcome of fluidic movement.
FDM and FEM
Two fundamental methods govern much of the CFD field: finite
difference methods (FDM’s) and finite element methods (FEM’s).
Both are umbrella terms that encompass a serious of equations
and principles—some more complex than others—that measure and
compare/contrast anything from Neumann boundary conditions, to
vortex phenomena, to compressible/incompressible flows.
Uses for CFD in the Real Word
CFD’s enable scientists, physicists, and chemists (among
others) to effectively simulate the flow of fluids and gases,
chemical reactions, fluid-boundary interactions and moving
objects. With a CFD program, prototypes of many different kinds
of systems or devices can be virtualized—which allows
professionals to study certain phenomenal insight that the data
and graphical renderings give. They then apply this insight—a
mixture of Newtonian physics, statistical mechanics,
thermodynamics, and chemistry, among others—to real-world
scenarios to fix or improve things, create better efficiency in
products or services, and invent new methodologies and/or
Copyright Gary Norton Developments 2010