Effect of an asymmetric flow disturber on an ultrasonic flowmeter

An ultrasonic flowmeter used in custody-transfer heat metering applications is subject to several test applications for approval. A flow disturbance test with an asymmetric swirl generator upstream of the device is performed to evaluate its accuracy with and without the swirl generator. This standard asymmetric swirl generator is designed to reproduce the behaviour of applications in the field, such as an out of plane 90 degrees double bend. To assess the compliance of the already approved device (Endress+Hauser Prosonic Flow E Heat) for heat metering applications with the standard asymmetric swirl generator, extensive Computational Fluid Dynamics (CFD) simulations are performed. The steady and transient CFD simulations are carried out on a High-Performance Computer (HPC) for several volume flows. With the developed automated simulation method, a virtual calibration of the device takes place. The calibration curves for the cases of a straight pipe, and an asymmetric flow disturber mounted upstream of the flowmeter are attained from experiments and simulations. The agreement of experiments and simulations is discussed and physical insight for the behaviour of the flow disturber and the flowmeter is gained.