Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.
How to analyze the equations of monopole point source when dealing with the acoustic pressure
Posted 2017年3月8日 GMT-5 11:20 Acoustics & Vibrations Version 5.2 0 Replies
Please login with a confirmed email address before reporting spam
I have been confused with the governing equations when conducting a case on room mode applying the monopole point source.
1/(ρc^2 ) · (∂^2 p)/(∂t^2 ) + ∇[-1/ρ · (∇p-q_d )]= Q_m
Q_m= 4π/ρ ∙ S ∙ δ(x-x_0)
S= e^iφ ∙ (iω · ρ_c · Q_s)/4π
Until now, I have checked many acoustic books, but only found the following similar equation.
∇^2 p- 1/c^2 ∙ (∂^2 p)/(∂t^2 ) = -ρ ∙ (Q_s (t) ) ̇ ∙ δ(x-x_0 )
So my questions are
1). While I put the monopole source as the initial condition, why there is a q_d that should be subtracted in the equation
1/(ρc^2 ) · (∂^2 p)/(∂t^2 )+ ∇[-1/ρ · (∇p-q_d )]= Q_m
2). What does φ mean in the equation
S= e^iφ ∙ (iω · ρ_c · Q_s)/4π
And what is the difference, in particular, between e^iφ and e^(i(ωt-kr)), which I have seen in many books?
Hello Li Dongfang
Your Discussion has gone 30 days without a reply. If you still need help with COMSOL and have an on-subscription license, please visit our Support Center for help.
If you do not hold an on-subscription license, you may find an answer in another Discussion or in the Knowledge Base.