Characterisation of textile shape and position upstream of a wastewater pump under different part load conditions

Accumulations of sanitary textile materials often lead to clogging of pumps in the wastewater system. Simulation of clogging phenomena may help to identify means of reducing the risk of clogging. In order to provide realistic initial conditions for clogging simulations, this study characterises textiles in artificial wastewater in the suction pipe to a dry-installed pump at nine different operating points. The textiles are recorded approximately 3.5 pipe diameters from the pump inlet and approximately three pipe diameters from the suction pipe bend at pipe Reynolds numbers in the range 300,000–900,000. Parameters of position, orientation, elongation and projected two-dimensional (2D) area are extracted using image analysis. The resulting parameters from the different operating points are compared using analysis of variance. The results show that the position, orientation and elongation do not change significantly with the operating point, while the projected 2D area decreases with an increased flow.