How engineers predict the flow effect on the body? Which instrument and techniques used for the flow effect prediction? When aircraft,spaceship,automobile move,air molecules around the body strike it.Velocity of body play crucial role in flow simulation. Speed is mainly in Knots and Mach.
Any ways ,CFD flow simulations and wind tunnel testing application used in aerospace industry for prediction flow effects on any moving body.
Flow simulation is the computational prediction of flow on anybody whether it’s blunt and slender. Flow simulation also brings the results of effects of flow on body with plots of pressure distribution, forces, velocity, temperature etc. In easy way we can say prediction of how this particular fluid flow effect the body on striking shearing.
WIND TUNNEL TESTING:
wind tunnel is an instrument which is very massive and bulky depending on the type of flow analysis. Subsonic wind tunnel and supersonic wind tunnel are 2 types. Subsonic wind tunnel are of 2 types open and closed. Subsonic wind tunnels occupies less space and provide the subsonic flow simulation of up to 0.7 Mach flow velocity. Supersonic wind tunnel occupies larger space and provides the flow simulation of Mach 1 to 5. Body which is going to be analysed is placed inside the testing section middle of the tunnel. Body mounted on support with fixtures. Air flow allow from inlet chamber and reach the outlet. During this process flow effect on body recorded by the system and observer.
Types of wind tunnel:
1.Open Wind Tunnel: Wind Tunnel which is opened from both sides where testing and observation occur in room. Used for subsonic testing.
2.Closed Wind Tunnel: Wind Tunnel which is opened from one side and closed from another side. In this tunnel air is circulated for testing and observation. Used for supersonic testing.
This Setup need larger area and team for simulation process.Setup and maintenance is costlier. Engineers are known as aerodynamicist (who study aerodynamics effect).
COMPUTATIONAL FLUID DYNAMICS (CFD):
Computational fluid dynamics or cfd flow simulations is the software application requires high performance processors and system for working and results. It’s the branch of fluid mechanics that uses the numerical methods and algorithms to solve and analyse problem that involve fluid flow. In this software we draw the domain and placed the geometry in domain. After that we do meshing of whole geometry for solving in solver. After thousands of iterations we get the results of flow simulation in various colors.
This Setup needs engineers who scrutinize the results and verify with their hand calculations. CFD flow simulations are more reliable and trustworthy. CFD flow simulations setup and maintenance is cheaper than wind tunnel testing setup. Modern flow simulation industry use CFD.