Recent content by huangchao

Hi, I have a general question about linear wave equation: Is solving the linear wave equation is equivalent to compute the output of a linear system where source is the input? Thanks in advanced! Chao

In my point of view, just the variation of density in time (or the condensation 's') is deliberately restricted to small values, not the density variation in space. Anyway, thank you so much and good night!

OK, I didn't find any problem of it, it's just a definition of fluid element.

Sure, but what I mean is no restriction of density variation in space, and surely there is a restriction of density variation in time. Just as it's stated in the book (at the bottom of pp. 115), quote, "The essential restriction is that the condensation is small."

Hi, Studiot, I just went through your derivation, and found no problem of it, so the equation (1) is valid and it requires no restrict about the variation of density in space, right?

OK, the link is: https://docs.google.com/leaf?id=0B347fzM7u3EfZTQ5NDhlN2EtZTBmYy00YzQ2LWJiMTQtMDk4NDRhZjliNDEy&hl=en&authkey=COHl_70M

I don't think there is any restriction regarding the variation of density in space during the derivation of equation (1) and (2). Do you want to see how equation (1) and (2) are derived in the textbook? I can share it with you via Dropbox or Google Docs.

yes, you are right, but this is the approximation used by equation (13) but not equation (7), so equation (7) is more general, right? Good night!

In Kinsler's "Fundamentals of Acoustics", on pp. 119-120, it claims, quote, "Since the above derivation never required a restriction on B or rho0 with respect to space, (5.5.4) (which is the same as equation (7)) is valid for propagation in media with sound speeds that are functions of space...

when I derived equation (7), I didn't make any assumption about the variation of density in space, which means equation (7) holds no matter the density varies in space or not.

Could you say it more specifically? What restriction did I apply to equation (7) other than equation (13)?

or the variation in time at every location is sufficient small.

When I say variation, I mean the variation in space. And assume there is no variation in time at every location.

I mean Eq. (7) is more fundamental in terms of that it can deal with strong density variation, while Eq. 13 is just a special case of Eq. 7 and only valid when density variation is small.

Hi, everyone, I have a question about the acoustic wave equations in two different forms (see the attached). I think the simpler form is more general (in terms of density variation) than the complex one, although the latter looks more general at first sight. But my advisor thinks it's the...