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CosmosWorks can be used to check the strength ofthe propeller design. In
CosmosFloWorks, the propeller is considered as a solid part without defonnation;
however, the propeller will be undergoing stress when it is rotating. FEA analysis is used
to check that the propeller is strong enough when it is rotating. CosmosFloWorks can
provide the resultant fluid pressure that is acting on the propeller blades. This pressure
difference is the source ofbending force, which results the stress that could cause a
propeller to be destroyed. CosmosWorks can be used to analyt:e propeller's strength by
FEA. CosmosWorks uses the fluid pressure as an input parameter to calculate the stress
within the propeller and dctennine the Factor of Safety (FOS). The value of FOS is
calculated by limit yield stress over each stress value. The acceptable FQS value for a
propeller is nol less than 1.5 [38}.lnstead of 1.5, some designers use 2 to make a higher
strength propeller. The FEA analysis can help engineers to choose a good material and
hub design to make sure the propeller design is strong enough. The steps of FEA analysis
are shown as below:
• Usc CosmosFloWorks to calculate the surface pressure of propeller blades
Transfer the CosmosFloWorks results to CosmosWorks in the Tools option
Create a static study in CosmosWorks
Load the CosmosFloWorks results file (.Od) into the static study
Set the restraint for the propeller. The bottom ofthe hub is fixed.
Select propeller material
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