What are the governing equations of CFD?
Navier-Stokes equations are the governing equations of Computational Fluid Dynamics. It is based on the conservation law of physical properties of fluid. The principle of conservational law is the change of properties, for example mass, energy, and momentum, in an object is decided by the input and output.
What is the general energy equation?
This is known as a general energy equation for a control volume. δ Q δ t − δ W δ t = ∂ ∂ t ∭ c v ( u i + V 2 2 + p ρ + g z ) ρ d V + ∬ c s ( u i + V 2 2 + p ρ + g z ) ρ V → d A → This equation holds good for non-uniform flow also.
What is meant by substantial derivative?
Substantial derivative is an important concept in fluid mechanics which describes the change of fluid elements by physical properties such as temperature, density, and velocity components of flowing fluid along its trajectory [61].
Why do we use convective derivatives?
The convective derivative arises naturally from the Eulerian formulation, and represents the rate of change of a parameter with time following the fluid element. It is the same as the lagrangian derivative, and allows us to determine the lagrangian derivative even though we are using an eulerian framework.
What is momentum equation in fluid mechanics?
The momentum equation is a mathematical formulation of the law of conservation of momentum. It states that the rate of change in linear momentum of a volume moving with a fluid is equal to the surface forces and the body forces acting on a fluid.
How is the substantial derivative of velocity vector denoted?
1. How is the substantial derivative of velocity vector denoted? Explanation: \frac{D\vec{V}}{Dt} is the substantial derivative.
What is momentum in fluid?
The momentum of a fluid is defined to be ρu, per unit volume. Newton’s second law of motion states that momentum is conserved by a mechanical system of masses if no forces act on the system. We are thus in a position to use (2.14), where the “sources and sinks” of momentum are forces.
What is the physical principle behind momentum equation?
1. What is the physical principle behind momentum equation? Explanation: Momentum equation is derived using Newton’s second law of motion. This gives a relationship between force and acceleration.