Hi 

I'm try to simulate time dependent vibration of a solid in a fluid media such as air in comsol but when i checked it, it shows a damping vibration if i use time dependent modal. 

for what we have damping behavior in the time dependent modal analysis.

all conditions for tow types of analysis are same.

pictures included.

Also i want a recommendation about using comsol is better for simulating acoustic analysis of a solid's vibration or ABAQUS.

thanks.