Flow Measurement in Pipes and Ducts

This course is about measurement of the flow rate of a fluid flowing under pressure in a closed conduit. The closed conduit is often circular, but also may be square or rectangular (such as a heating duct) or any other shape. The other major category of flow is open channel flow, which is the flow of a liquid with a free surface open to atmospheric pressure. Measurement of the flow rate of a fluid flowing under pressure, is carried out for a variety of purposes, such as billing for water supply to homes or businesses or, for monitoring or process control of a wide variety of industrial processes that involve flowing fluids. Several categories of pipe flow measurement devices will be described and discussed, including some associated calculations.

Upon completion of this course, the participant will be able to: • Calculate liquid flow rate from measured pressure difference, fluid properties, and meter parameters, using the provided equations for venturi, orifice, and flow nozzle meters. • Calculate gas flow rate from measured pressure difference, fluid properties, and meter parameters, using the provided equations for venturi, orifice, and flow nozzle meters. • Determine which type of ISO standard pressure tap locations are being used for a given orifice meter. • Calculate the orifice coefficient, Co, for specified orifice and pipe diameters, pressure tap locations and fluid properties. • Estimate the density of a specified gas at specified temperature and pressure using the Ideal Gas Equation. • Calculate the velocity of a fluid for given pitot tube reading and fluid density. • Know the general configuration and principle of operation of rotameters and positive displacement, electromagnetic, target, turbine, vortex, ultrasonic, coriolis mass, and thermal mass meters. • Describe the recommended applications for each of the type of flow meter discussed in this course. • Describe the general characteristics of the types of flow meters discussed in this course, as summarized in Table 2 near the end of this document.

Dr. Bengtson is a graduate of Iowa State University with B.S. and M.S. degrees and of the University of Colorado with a PhD. He is a licensed Professional Engineer in Missouri. He has spent 30 years in engineering education in teaching and administrative positions, including six years as Dean of Engineering at Southern Illinois University Edwardsville. His areas of expertise are environmental engineering, hydrology and hydraulics, engineering science and renewable energy systems. He did consulting work while holding the academic positions. Prior to entering academia, Dr. Bengtson worked for Minnesota Mining & Manufacturing as a Product Development Engineer and for E. I. duPont deNemours as a Process Development Engineer. Dr. Bengtson has authored numerous publications, presentations and technical reports. He is currently active in providing continuing education opportunities for Professional Engineers and is the founder of www.engineeringexceltemplates.com and www.EngineeringExcelSpreadsheets.com, sites with the objective of providing inexpensive, easy to use Excel spreadsheets for a variety of engineering calculations.