[MFGT]

Hello,

i have a couple of questions, i hope its fine to collect them here in one thread:

1.) Does the Solver get efficient with newer releases? E.g. i am using the 2.3.10 version now, and update to the newest as soon as possible, because there are always some nice added features. Are there changes in results? I remember a comparison I found for major updates (2.2 vs 2.3 for example).

2.) Regarding Injection, i sometimes have issues using the spray rate calculator. In general, i set it up with injection time (CA or sec), injection mass and injection pressure. Then i copy the resulting discharge coefficent and enter it in the corresponding box. I do this, because Studio often loses the entered values in the additional settings (fuel pressure).

Which discharge coeff. model is recommended?
Sometimes i receive error message: Warning, area correction factor > 1.0, setting = 1.0 (velocity_coeff = 0.76914) when using 1 (using correlation for cv).

3.) For Gasoline DI and PFI, i am using the Kuhnke wall film model with default inputs. How are the experiences there or what is best practice?

4.) The optical representation of the fuel in EnSight has a lot of options. Are there recommended settings to use? E.g. i use sphere with size by dp_radius with a value of 5. And reduced polygons of 0-2. Otherwise i have too many dots and chaos on screen.

edit:
5.) In my recent simulations i experienced a strange behaviour with the reaction ratio. If combustion starts, it should decreasae, because O2 is consumed. However, it does exactly the opposite and i can verify in EnSight, that its rising at the location, where my fuel and O2 is consumed (actually both go to zero). The reaction ratio is the same as equivalence ratio, only without considering CO2 and H2O, right?

6.) Can i ignore the following warning which i receive with default inputs? WARNING: in inputs.in mult_dt_coll_mesh is greater than 1.0. this may lead to large errors in spray calculations


Thanks a lot.
Tobias