Propeller blade pressure + centrifugal force to analyze blade flexion and clearance

Adrunodro

Hi,

I want to analyze the clearance of a pushing propeller and stresses. I have seen that I should use RFORCE to simulate centrifugal force but I don't know how could I combine that force with the pressure on the blade. When the static analysis is defined I have choose either PRESSURE or RFORCE. I can't use superposition as RFORCE doesn't make any difference in the flexion of the blade until some deformation from PRESSURE occurs.
How could I combine both?

Robert Hoglund

Hello,

If you're asking about the OptiStruct solver, RFORCE is defined by a card image from a load collector, while pressure is not. One load collector for RFORCE, another one to define pressure loads, and if you want to combine them in the same static step, reference both using loads using another load collector with LOADADD card image (see below).

IF you want to simulate sequential effects, look at STATSUB(PRELOAD) to define preloaded analysis to simulate a pre-stressing of the blade (this requires the two subcases then, one with centrifugal loading and one with pressure).

Thanks,

Rob

Robert Hoglund

Hello,

If you're asking about the OptiStruct solver, RFORCE is defined by a card image from a load collector, while pressure is not. One load collector for RFORCE, another one to define pressure loads, and if you want to combine them in the same static step, reference both using loads using another load collector with LOADADD card image (see below).

IF you want to simulate sequential effects, look at STATSUB(PRELOAD) to define preloaded analysis to simulate a pre-stressing of the blade (this requires the two subcases then, one with centrifugal loading and one with pressure).

Thanks,

Rob

Robert Hoglund

Attached documentation about Prestressed linear analysis.

Rob