The original test bench proposal allowed for testing of centrifugal pumps for a range of power from 10 kW to 50 kW and a maximum head of 70m. This allowed for a corresponding maximum flow rate of around 1000m3/h.
During a meeting, partners asked if it was possible to extend the range of flow rates above 2000m3/h and if submersible pumps could be tested instead of the centrifugal ones. This is important due to the range of pumps in use within the partners organisations.
It was agreed to revise the design to enable submersible pumps to be tested at a higher flow rates (rather than the original 1000m3/h). However, two major constraints would result from these new operating limits:
- Submersible pumps need to be submerged in a large reservoir to avoid the formation of a vortex at the suction side of the pump. This increases the tank diameter and the stresses on the whole structure
- Many submersible pumps are integrated with the motor which prevents any individual testing of the pump and the motor from being achievable.
Three alternative designs were discussed and the meeting participants clearly expressed their preference for the first proposal, allowing the whole range of pumps to be tested.
The new proposal, a Test Bench Mechanical Design and Lab Integration, will include a 3m diameter and 4.5m high Tank that will be positioned outside of the lab. This design enables testing of both centrifugal and submersible pumps for a mass flow rate up to 2000m3/h. The tank can be pressurized from 0.5 bar absolute to 2 bar relative allowing the suction head to be controlled from 5m to 20m. The pump head can range from several metres to 80m. The maximum diameter of the submersible pump to be tested is 1.5m for a maximum height of 2m.
This enhanced test bench will allow to test and evaluate the sites which have been proposed in the Application but it will also expand our ability to test a range of other sites and improve the long-term effects of the project.