A 4m wide culvert running more than 2m deep takes cooling water from Ratcliffe-on-Soar Power Station into the adjacent receiving water flowing in excess of 7,000l/s. The size of the culvert, the high flow velocity and access limitations presented a difficult challenge when it came to the need to accurately determine flow rate.

EMS devised a methodology to map the flow velocity. Thirty measurements were taken within the cross-section of the culvert using a spot velocity meter. Additionally, two area-velocity meters were used to check the consistency of the flow conditions temporally and spatially through the water column in order to verify the uniformity of the flow field. The methodology was repeated for four independent flow velocity tests.

The average flow velocity within the culvert based on the results from the four tests was 0.73m/s with a calculated maximum error for the methodology of 1%. This figure was calculated based on four traverses and based on a weighted average of the velocity measurements using the weightings from the profiling. This allowed the high level of accuracy in the large culvert with such fast flow.

For more information please contact EMS.