Benchmark solution
=====================


Calculation method
-----------------

This test case aims to compare two different formulations for fluid elements. We will therefore have exclusively numerical comparisons.


.. _RefHeading__163478_637747685:


Reference quantities and results
-----------------------------------

In order to choose an interesting point of comparison, we plot the acceleration at the **C** post-treatment point with and without a fluid border in the case of formulation :math:`(u,p)`. As can be observed in the, the absence of the fluid border causes a phase shift effect due to parasitic waves from the left border of the fluid.


.. image:: images/10000201000007D000000514A1636FAFB201AE9C.png
    :width: 5.5118in
    :height: 3.5783in


.. _RefImage_10000201000007D000000514A1636FAFB201AE9C.png:

**Figure** 2.2-a **: Acceleration at post-treatment point C with and without a fluid absorbent border**