Study of Hot Wire Anemometry and Flow Measurement Elements

Abstract

In industries,flow of any fluid varies over a very wide range.It ranges from very low to very high velocity. Because of this variation, various types of flow measurement elements have been developed. Out of all these, hot wire anemometer, orifice meter and rotameter are widely used. Responses of fluids with different densities and sensors with different diameters have been studied. Since these components are delicate to heat exchange between the component and its composition, temperature and environment, their responses vary with conditions provided. Using hot-element sensor we also measured the concentration of gas components in a mixture of two known gases. This method is based on thermal conductivity of mixture. Thermal conductivity of mixture depends on individual thermal conductivities of gases of mixture and individual fractional concentration of that gases. Taking different types of probes and different types of fluid we compare the behavior of sensor so that we can determine the best conditions for measurements of properties like velocity and composition of fluids. We also design and analyze the fuel metering valve. Fuel metering valve show nonlinear behavior and traditional methods are only optimize and analyzed the systems which is linear control system. Using flow gain (G) the fuel metering valve’s flow rate is linearized. The relation between flow orifice’s shape, along with rectangular, circular and triangular shape and its gain of steady state flow is discussed at the end. Flow measurement is also done using rotameter. It is a constant pressure and variable area type flowmeter. Though with accuracy around 2%,it has gained a lot of importance in today’s industries. We have also designed diameter for orifice plate considering different properties of fluid flowing through it like density, specific heat ratio, dynamic viscosity etc. Thus, a thorough study of flowmeters has been done.