Author(s): Mahmood Naghash
Linked Author(s): Mahmood Naghash
Keywords: No Keywords
Abstract: A swirl meter (also known as a vortimeter or rotometer) is a custom-built instrument necessary for measuring the intensity of any flow rotation in the pump column or suction pipe of a physical hydraulic model study for pump intake structures. The design of the swirl meter varies with the laboratory performing the physical model testing, and frequently its design is proprietary. The Hydraulic Institute standard (ANSI/HI 9. 8-2012) specifies the swirl meter geometry requirements, the acceptance criteria, and states a low friction bearing to be applied for rotating mechanical module of the swirl meter. However, since the details of the mechanical rotating module are not specified, the sensitivity of the swirl meter varies widely among testing laboratories around the world. The varying swirl meter rotating module design requires varying drag force to provide the same rotational speed. Consequently, the swirl meters made by different testing laboratories results in varied measured swirl angle for the same physical model creating inconsistent results. This paper reexamines the swirl meter design and implementation guidelines and provides suggestions for a standard design. Also, due to decay of swirl intensity with distance along a pump column, the location of the swirl meter in a pump column is reevaluated.
Year: 2013