Dear Pravin,
I’ve not had personal experience of taking the lumped load output from a beam-type model and applying that to an 3D FEA model to find stress/strain. I would guess that applying the lumped loads directly would result in unrealistic stress concentrations. I’ve read the following paper where they recommend to linearly distribute the load along the chord, but I cannot say whether that is a typical approach. Hopefully someone else with more experience in this area can comment.
Berg, J. C.; Paquette, J. A.; and Resor, B. R. “Mapping of 1D Beam Loads to the 3D Wind Blade for Buckling Analysis.” 52nd AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference. 4-7 April 2011, Denver, Colorado. AIAA 2011-1880.
Best regards,