College of Engineering News • Iowa State University

OpenQBMM software simulates multiphase flow behavior

Alberto Passalacqua, associate professor of mechanical engineering and associate director of the Center for Multiphase Flow Research and Education (CoMFRE), is leading the development of the software OpenQBMM at Iowa State. 


OpenQBMM is an open-source multiphase flow computational fluid dynamics (CFD) software designed to simulate the behavior of flows with particles, bubbles, or droplets. The Advanced Computing Infrastructure Program at the National Science Foundation supported the development of this software. 


The applications of OpenQBMM span many industries, including the production of drugs and polymers in the chemical industry, waste treatment in the biological industry, the simulation of sprays in engine injectors in the automotive industry and weather forecasting.


OpenQBMM also has an extremely timely application: it gives researchers in the health industry the ability to understand the spread of droplets released while breathing, which may spread infections.


Beginning development


Passalacqua, who also holds a courtesy appointment in the Department of Chemical and Biological Engineering, began developing OpenQBMM in 2014 after completing his post-doc and continued when he became a faculty member at Iowa State. He began working on this software because he saw a need for programs with up to date methods to predict the behavior of multiphase flows. 


“You could buy software that promised to do simulations of multiphase flows, but the description of physics was not necessarily what we knew then about physics,” Passalacqua said. “These programs were a decade or more behind the academic developments.”


Collaboration is key


The development of an in-depth program like OpenQBMM required interdisciplinary collaboration. Passalacqua worked with other researchers throughout math, physics and computer science including Rodney Fox, Anson Marston Distinguished Professor of Engineering and Hershel B. Whitney, Global Initiatives Professor, in the Department of Chemical and Biological Engineering; Shankar Subramaniam, professor of mechanical engineering; and Simanta Mitra, associate teaching professor of computer science, plus a group of postdoctoral scholars, graduate students and visiting researchers.


Passalacqua also spent two summers at the Laboratoire EM2C, CNRS, CentraleSupélec, Université Paris-Saclay, where he improved his knowledge about some of the numerical methods used in OpenQBMM collaborating with Frédérique Laurent, a recognized expert in the field.


“When we started working on OpenQBMM, we planned to bring the knowledge to the user that we had as a group of researchers in CoMFRE,” Passalacqua said. “Before creating OpenQBMM, we had done a lot of development of methods to simulate multiphase flows and communicated it through traditional academic channels of publications and conference presentations. With this program, we can combine all of our knowledge and bring it to the user.”


CoMFRE was beginning while the OpenQBMM software was in development. As both the research center and software have grown, CoMFRE has been a key to OpenQBMM’s dissemination. 


“OpenQBMM has gained much visibility, thanks to CoMFRE. It has become an optional module for OpenFOAM, the leading open-source toolkit for CFD, becoming accessible to an international community of scientists and engineers,” Passalacqua said. “Networking is crucial to programs like this because we can write all the code we want, but if it just sits on a website and nobody knows about it or what it can do, then it is very challenging to reach potential users. The outreach CoMFRE does is critical in this sense.”