Sneezing Simulation

— DPMFoam, Lagragian solver without carrier phase coupling —

Based on the virus that appears in 2019 in Wuhan and the followed up world crisis, many simulations regarding sneezing and coughing popped out at several social platforms such as LinkedIn, Twitter, or YouTube. This inspired Tobias Holzmann to investigate more into the Lagrangian solvers. The outcome was a sneezing simulation based on the DPMFoam.

— Particle distribution is based on a publication. The sneezing velocity was assumed on some articles —

The particle distribution was taken from Han et al. (Characterizations of the particle size distribution of the droplets exhaled by a sneeze). The bimodal data set of 20E was used. The given logarithmic equations were used to generate distribution data. These data were exported to OpenFOAM®; set into the kinetmaticCloudProperties. The distribution type in use is »general« while providing the data given in the plot below.

— Assumed Sneezing Velocity —

Assumed Sneezing Velocity

— Droplet Distribution based on Han et al. —

Droplet Distribution

To get a more realistic investigation, the velocity profile was further manipulated. Arbitrary fluctuations were added to the different parts of the velocity vector while keeping the magnitude of the velocity conserved. For this purpose, the codedFixedValue boundary condition was used. The analysis of the video shows the bimodal size distribution as the smaller droplets stay longer at the same place and fall down much slower compared to the larger droplets. Different discussions were performed regarding missing models such as a »break-up« model. However, as the size distribution already incorporates (maybe partially) the break-up of the droplets, the analysis might go into the correct direction..

Sneezing Simulation Visualization 1
Sneezing Simulation Visualization 2
Sneezing Simulation Visualization 3

— Published under the GNU General Public License 3

Over the last ten years, Tobias tried to publish a wide range of different materials related to OpenFOAM® and CFD. You know it much better than he does if the content is worth to be supported. If you want to thank Tobias for the work he did, feel free to tell the community your opinion about the work Tobias Holzmann is doing or you can email your thoughts directly to »This email address is being protected from spambots. You need JavaScript enabled to view it.«. Keep in mind that the work that was done here took much time, and it is not self-evident that Tobias Holzmann shares all his work, knowledge, and attitude for free and keep the data up to date. Hosting the material, updating the data, and keeping up interesting work for the community does take much time and also money. Supporting Tobias can be done by donating any amount you would like to give or help him with his projects.

Support the work of Tobias Holzmann

The available training cases are tested and built for different OpenFOAM® versions. During the tests, only the OpenFOAM Foundation version of OpenFOAM® was used. Furthermore, the following software packages are required for most of the training cases: Salome®, ParaView®, and for optimization tasks one also needs DAKOTA®. The cases might work with the ESI version of OpenFOAM® too (not tested). Additionally, there is no support for Windows-based OpenFOAM® versions.

Released 03.05.2020 — Downloads: