57:020 Mechanics of Fluids and Transfer Processes
Exercise Notes for the Pipe Flow TM
Measurement of Flow Rate, Velocity Profile and Friction Factor in Pipe Flows
S. Ghosh, M. Muste, M. Wilson, S. Breczinski, and F. Stern
The purpose of this investigation is to provide students with
experience using a pipe stand test facility
and modern measurement systems including pressure transducers, pitot probes, and computerized data acquisition with
Labview software, to measure flow rate, velocity profiles, and friction factors in smooth and rough pipes, determining
measurement uncertainties, and comparing results with benchmark data.
Additionally, this laboratory will provide an
introduction to PIV analysis, using an ePIV system with a step-up model.
The experiments are conducted in an instructional airflow pipe facility (Figure 1).
The air is blown into a large
reservoir located at the upstream end of the system. Pressure builds up in the reservoir, forcing the air to flow through any
of the three horizontal pipes.
Pressure taps are located on each pipe, at intervals of 1.524m, for static pressure
Characteristics for each of the pipes are provided in Appendix A.
At the downstream end of the system, the
air is directed downward and back, through any of three pipes of varying diameters fitted with Venturi meters (Figure 2).
The top three valves control flow through the experimental pipes, while the bottom three valves control the Venturi meter
to be used. The Venturi meter with 5.08cm diameter is used to measure the total flow rate, while the other two are kept
closed. Six gate valves are used for directing the flow.
The top and bottom 5.08cm pipes are used for measurements, while
the middle one is kept closed during the experiment. Velocity measurements in the top and bottom pipes are obtained using
pitot probe (Figure 3).
Airflow pipe system
Pressures are acquired either manually, using simple and differential manometers for data acquisition, or
automatically, with the manometers connected to an automated Data Acquisition (DA) system that converts pressure to
voltages using pressure transducers.
Data acquisition is controlled and interfaced by Labview software, described in
The schematic of the two alternative measurement systems is provided in Figure 4.
Manual and automated measurement systems used in the experiment