I'm working on validating through flow simulation a known marine propeller with the following data:
Thrust is suppose to be around 23 [N] (calculated), with effic. > 0.7 for the very least.
Creating the model on solidworks i had the control of how to place the blades (their pitch) against the hub.
It was set as 50.5 deg at r/R=0.2 manually, and the simulation results show a symmetric velocity and pressure profile around the blades with this setting (as opposed to when I tried setting at different angle which either shown no symmetry or no high-low pressure profile above and behind the blade section view).
Problem is the results I get for the thrust and torque (too low as well) do not make sense.
Thrust is too low (around 1-3 [N] after full convergence) with a torque of approx. 1 [Nm] which gives a VERY bad efficiency rate (does not make sense).
Removing/Changing hub geometry has negligible effects (tried no hub, cylinder hub and the attached 'improved' hub adding 1 [N] compared to a goal of 23 [N])
Any guidance would be much appreciated