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blizzard May 25, 2017 15:22

Help! Trying to understand lax wendroff
 
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Hi,

So I am a student taking Intro to CFD and I am currently working on an assignment to understand Lax Wendroff method.

I have attached the problem and the work I have done. I am not looking for someone to do the work for me but to help me in the right direction.

Thank you in advance to all who read and help me on this FUN journey .

FMDenaro May 25, 2017 15:29

Have a look to this book

http://mathcenter.hust.edu.cn/Upload...98740d59f8.pdf

blizzard May 25, 2017 16:19

The problem I am currently having is that I do not understand how to go from what I have as Eq C to getting the truncation error and nothing seems to show why the truncation error is O[deltaX^2, deltaT^2]

FMDenaro May 25, 2017 16:26

Quote:

Originally Posted by blizzard (Post 650297)
The problem I am currently having is that I do not understand how to go from what I have as Eq C to getting the truncation error and nothing seems to show why the truncation error is O[deltaX^2, deltaT^2]


Just start from the discretized LW equation, use the Taylor expansion in time and space to rewrite the function in (x,t). All the terms appearing out of the original PDE represent the local truncation error.
In the book you find the section for the local truncation error of a scheme.


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