Effect of channel geometry on the performance of the Dethridge water wheel

Dethridge water wheel is a simple hydraulic machine originally invented for measuring volume of flow supplied to the farms. The wheel has been in widespread use for more than a century for the application of water charges in irrigated farmlands. The Dethridge water wheel resembles distinct characteristics making it a suitable device for utilising very low-head sites within irrigation canals, small streams and at the outlets of the waste water treatment plants for pico-hydropower generation. In this paper, performance characteristics of the Dethridge water wheel model is studied in different channel geometry settings. Different wheel to channel width ratios and gradual transition shapes were tested. The wheel performance improves in the channel width that is two to three times greater than the wheel width. The gradual transition shape has however insignificant impact on the performance of the wheel.