The accuracy in measurement of flow rate of liquids and gases is an essential requirement for maintaining the quality of industrial processes and the industrial control loops are used to control the rate of flow of incoming liquids or gases so as to achieve the control objective. Different types of flow measuring techniques are being used in various industries. The common types of flowmeters used in industrial applications are : (a) Obstruction type (differential pressure or variable area) (b)

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... nferential (turbine type), (c) Electromagnetic, (d) Positive displacement (integrating), (e) fluid dynamic (vortex shedding), (f) Anemometer, (g) ultrasonic and (h) Mass flowmeter (Coriolis). Pressure probe is one of the common instruments used to measure the stagnation pressure, the static pressure, and the flow angle within a fluid stream. When we are designing a pneumatic probe for flow measurements, the effects of blockage, frequency response, pressure hole size and geometry, the local Mach and Reynolds numbers and the relative scale of the phenomena under study must be addressed. Five-hole probes are a newer type after the development of two-hole Conrad and three-hole Cobra probes which are used to measure the pitch and yaw angles of the flow, the stagnation pressure and dynamic or static pressure. Here, five hole probe is fabricated and then calibrated by using continuous wind tunnel. It can be extensively used for three dimensional flow measurements. It is a good alternative to costly techniques of flow measurement.