Bubble Swarms and Reactive Mass Transfer at Dynamic Interfaces

In the proposed work, it is our goal to investigate the complex dynamics of dispersed multiphase flows and their influence on (bio-)chemical reaction processes. In the pursuit of this goal, both numerical and experimental methods will be used. Specifically, the aims of the proposed work are: (1) To develop a model, which allows direct numerical simulations (DNS) of chemical reactions taking place in bubbly gas-liquid flows with dynamically evolving interfaces. This part of the project will focus on the dynamics of the motion of single bubbles, bubble swarms, oscillating bubbles, Non-Newtonian liquids and will help to shed light on the connection between bubble properties and flow characteristics and their impact on reaction product distribution. We will also develop closures for use in reactor simulation models. (2) To apply the model to a number of multiphase systems encountered in chemical and biochemical industries. Such systems include oxygen delivery and shear stress in cell cultures, particulate transport and removal in industrial effluent gas streams and non-Newtonian flows amongst others. These investigations will grant better understanding of the dynamics of the flows in these systems and their role in controlling chemical and biochemical processes, ultimately leading to better design and operation = "process intensification". (3) To experimentally confirm the results produced by numerical simulations and to use 3D DNA and VOF simulation for comparison. For this purpose, experimental studies will be conducted by our group, as well as by other groups, we are collaborating with on this project. These studies will focus on different experimental systems (both gas-liquid and liquid-liquid) that are relevant to the bio- and pharmaceutical industries. 3D DNS will be carried out by us, but we will use VOF results by other groups (e.g., Bothe) to verify our work. (4) To aggressively pursue hiring of women in our research team. This will further enhance the role of women in science and technology.

In the proposed work, it is our goal to investigate the complex dynamics of dispersed multiphase flows and their influence on (bio-)chemical reaction processes. In the pursuit of this goal, both numerical and experimental methods will be used. Specifically, the aims of the proposed work are: 1. To develop a model, which allows direct numerical simulations (DNS) of chemical reactions taking place in bubbly gas-liquid flows with dynamically evolving interfaces. This part of the project will focus on the dynamics of the motion of single bubbles, bubble swarms, oscillating bubbles, Non-Newtonian liquids and will help to shed light on the connection between bubble properties and flow characteristics and their impact on reaction product distribution. We will also develop closures for use in reactor simulation models. 2. To apply the model to a number of multiphase systems encountered in chemical and biochemical industries. Such systems include oxygen delivery and shear stress in cell cultures, particulate transport and removal in industrial effluent gas streams and non-Newtonian flows amongst others. These investigations will grant better understanding of the dynamics of the flows in these systems and their role in controlling chemical and biochemical processes, ultimately leading to better design and operation = "process intensification". 3. To experimentally confirm the results produced by numerical simulations and to use 3D DNA and VOF simulation for comparison. For this purpose, experimental studies will be conducted by our group, as well as by other groups, we are collaborating with on this project. These studies will focus on different experimental systems (both gas-liquid and liquid-liquid) that are relevant to the bio- and pharmaceutical industries. 3D DNS will be carried out by us, but we will use VOF results by other groups (e.g., Bothe) to verify our work. 4. To aggressively pursue hiring of women in our research team. This will further enhance the role of women in science and technology.