Development of the pressure-time method

The Winter-Kennedy method is seen as cost-effective for efficiency and efficiency step-up measurements and is nearly exclusively used in Sweden. The simplicity of the method and its cost effectiveness makes it a prime candidate for online flow rate monitoring. However, in Sweden there are numerous low head machines installed. Absolute flow measurements with good accuracy for such machines are difficult and costly, mainly due to the variable and large geometry of the intakes. An absolute and accurate flow measurement method for low head machines is required for relevant efficiency measurements. The pressure-time method is one such absolute method with promising capabilities, but less used in Sweden. The goal of this PhD project is to develop a new test rig at Luleå tekniska universitet to test the pressure-time method with application to allow head hydraulic turbine with variable cross-section intakes.

The pressure-time method may be used to calibrate an inexpensive relative method, such as the Winter-Kennedy. The combination of the pressure-time method and the Winter-Kennedy method is attractive as it would be simple to implement and maintain and is cost-efficient. Nonetheless, the pressure-time method has limitations which need to be overcome for a wider acceptance, which is the objective of the present work.

In short, this project will: