Two modular side channel pump models have been investigated both numerically and experimentally. For both modular designs, different side channels and impellers could be studied, with the aim to get information about the influence of the different geometries on the performance and the inner flow phenomena of the pump. By understanding the geometry influences, statements about the design process of the pump are possible. Changes of the geometry of the side channel or the impeller affect the flow in both components. This means that the geometrical dimensions must always be related to each other, in order to make statements about influences of the geometry on the characteristics. Thus, various geometrical configurations are setup, their sizes in industrial pumps are indicated and their influence is investigated by simulations. To evaluate the gained numerical data, it is important to understand the influence of mesh and simulation setup on the results. Therefore, a grid study was conducted and additionally the turbulence model was varied. In this paper, two parameters are focused on: these are the side channel height to the blade length (h/l) and the depth of the side channel in relation to the width of the blade (t/w).

Due to the centrifugal effect of the radial impeller, side channel pumps are a kind of regenerative pumps that provide high head at low flow rate. The geometry of the impeller affects flow patterns and energy conversion directly, greatly influencing the performance of side channel pumps. To investigate the effect of blade profile for suction side on the performance of a side channel pump, three different base angles of 10 , 20 , and 30 , respectively, on the blade suction side were discussed and analyzed both with numerical and experimental methods. The hydraulic performance, exchange mass flow, and velocity vectors were discussed in detail. The numerical work was validated by the comparison between the simulated result and tested result. The results show that the hydraulic performance of the impeller with 30 angle is the best one of the three impellers, especially for head performance. The evaluation method based on exchanged mass flow also confirms that the performance of the side channel pump can be improved by increasing the angle on the suction side of the blade. In addition, the radial vortex on the impeller flow passage has negative effect on the performance of the side channel pump. However, the axial vortex among the impeller and side channel directly affects the energy conversion and has a beneficial effect on the performance of the pump. The results could be used to modify the design models and conclude the effect of blade shapes on the performance of a side channel pump.

For side channel machines, distinction is made between side channel pumps and peripheral pumps. The blade number of side channel machines has a large influence on the performance of the pump. This is known from several experimental studies. For industrial side channel pumps, the blade number is between 20 and 26, whereas for industrial peripheral pumps, the blade number is much larger (between 36 and 90). In this paper, the influence of the blade number on the performance and the inner flow phenomena of different pumps will be investigated experimentally and numerically. The inner flow of the pump is examined in detail by computational fluid dynamics (CFD) simulations. Flow angles and velocities of the circulation flow between side channel and impeller are considered for different blade numbers. To explain the influences of the blade number, numerical results and theoretical formulas are combined. The experiments are carried out for two different modular side channel pump units, which differ in the side channel height h, the outer impeller diameter da, and the length of the blades l. So, the influence of the blade number can be studied in the context of other parameters like, for example, the relation between blade length and outer diameter of the pump. The obtained numerical results are compared with experimental data. Effects of the blade number on the performance curves of the pumps are shown by experimental and numerical results.