Dear researchers,
I am modeling the process of the water droplet impacting on the wall with a constant contact angle. The specific calculation parameters are as follows:
The droplet diameter is 1.97mm, the impact velocity is 0.96m/s, the calculation area is 2D axisymmetric area, the calculation area size is 6mm*6mm , the grid size is 10 μ m*10μm, all the residuals are 1e-6, and the time step is 1e-8s.
The calculated results are not the same as the experimental results, which shows that the movement of water drops in the numerical calculation is faster than that in the experiment. In other words, the numerical spreading diameter is twice as large as the experimental results at the same time.
Can someone help me solve this problem?
The reference of this calculation example is 《Droplet breakup and rebound during impact on small cylindrical superhydrophobic targets》
Best，
Yongkui Wang
For developing proper understanding of the droplet impingement I would recommend you to go though the following journal articles (attached). Moreover you may follow the following tutorial (https://www.youtube.com/watch?v=MN2zMoF3NyE) for your help. Make sure you have turned on wall adhesion and gave proper surface tension value. Moreover, rub your simulation with small time step for better convergence.
Hello
Which force do you apply on droplet particles? Drag force, lift force, virtual mass force, pressure gradient force,...?
In fact, each one of these forces will affect your modeling.
Also, your background flow (Eulerian phase) will affect your lagrangian phase if it did not converge well.
Hi,
It is a tricky question since there are too many factors that influence the problem. But I will try to give some ideas:
1. Check the ranges of diameters and velocities where the used model is valid.
2. Check if you are using the right simulation method to simulate the process.
3. Check how do you input the surface tension forces since it is very different in the case of superhydrophobic surfaces
4. Also keep in mind that this problem is still under research and there are a to of models in the literature.
I hope this will help
Mahabat Khan
Hi, Thank you for your help. I've checked the surface tension setting section to make sure it's correct. I'll look at the document you provided for help.
Mahdi Rezaei Adariani
Hello,
Thank you for your attention. I used the VOF multiphase flow model in fluent. The gravity, surface tension, viscous force and other factors are mainly considered in the process of water droplet transportation.
- Badges
- Science topic