ABSTRACT
A large variety of measurement techniques are used in the field of experimental fluid mechanics. Wind tunnels are used for numerous investigations ranging from fundamental research to industrial aerodynamics. Many wind tunnel studies aim at the determination of forces on scaled models of aircraft, aircraft components, automobiles and buildings. Apart from the conventional methods of experimentally investigating flow patterns by means of pressure and velocity surveys, fluid flows lend themselves to numerous visualization techniques. The repeatability of an instrument is its ability to display the same reading as long as its sensor element is fed the same signal. The reliability of a measuring system is the probability that it will operate with an agreeable accuracy under the conditions specified for its operation. Pressure, temperature, and volume flow/mass flow rate are the prime quantities associated with any fluid flow experimentation. A thorough knowledge of the fundamentals of fluid mechanics is inevitable for any successful experimentalist.
