# Getting problem to write a flux term codes in DG of Navier-stokes

**URL:** <https://community.freefem.org/t/getting-problem-to-write-a-flux-term-codes-in-dg-of-navier-stokes/3860>\
**Category:** General Discussion\
**Created:** [April 13, 2025, 7:56am UTC](https://community.freefem.org/t/getting-problem-to-write-a-flux-term-codes-in-dg-of-navier-stokes/3860 "2025-04-13T07:56:35Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![Monirul25](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.freefem.org/monirul25/32/3287_2.png) [@Monirul25](https://community.freefem.org/u/Monirul25)\
**Post date:** [April 13, 2025, 7:56am UTC](https://community.freefem.org/t/getting-problem-to-write-a-flux-term-codes-in-dg-of-navier-stokes/3860/1 "2025-04-13T07:56:35Z")

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Dear all experts and respected professors, i am getting problem to write the FF++ code of the following flux of F in the FF++:

 ![image](https://canada1.discourse-cdn.com/flex030/uploads/freefem/original/2X/0/0e3a9848fdae3f3ac7737b731b88b2e6c67e37f6.png)  
( **Getting problem to write second term and third term in FF++ code also third term is non-linear** )  
 ![image](https://canada1.discourse-cdn.com/flex030/uploads/freefem/original/2X/2/2402e219b271601a5e6fb56288d20b59e87c4351.png)

 ![image](https://canada1.discourse-cdn.com/flex030/uploads/freefem/original/2X/9/952c33da5a3a1dba7ca5258221a0a0d7cae58057.png)  
 ![image](https://canada1.discourse-cdn.com/flex030/uploads/freefem/original/2X/9/923c46a30e9b042c99a07167a77e3fd2e6d028b7.png)  
Here, is the details paper:  
[DDG of NS 2019.pdf](https://community.freefem.org/uploads/short-url/wGcBFTVM47pxo1WGccgMRfB0Yo9.pdf) (7.1 MB)

I have tried to write in the following way but not getting:

 ![1744530876590](https://canada1.discourse-cdn.com/flex030/uploads/freefem/original/2X/1/1c0b7286939a2342091e4cf8632ed44659d6b276.jpeg)

Thanks in advance!.