Fluid Flow and Heat and Mass Transfer in Micro-systems with Complex Physics

点击翻译按钮获取中文摘要

Fluid flow and heat and mass transfers in micro devices have many engineering applications in utilizing, detecting, sensing, monitoring, and diagnosis of environmental, industrial, biological, and biomedical systems. There is a need for cheap, reliable, real-time devices to diagnose diseases, monitor environmentally harmful gases, detect biological and chemical warfare agents, etc. The focus of the current proposal will be on investigating the physics of flow and droplets in microfluidic systems. Mathematical models and simulation tools need to be developed. The newly created knowledge leads to better understanding the operation of droplet micro devices, improve the design of novel diagnostic devices, such as flow focusing and digital droplet devices, and in developing a new technology. In the long term, it is intended to expand our results for developing industrial and environmental monitoring devices. ***Microfluidic and Nanofluidic devices have emerged as potent instruments for diagnosis of diseases. Extensive research has been done on different types of microfluidic devices for a wide spectrum of applications with different geometrical configurations. However, most of the works are done by a trial and error to optimize the operation in those devices. The flow is laminar, where the mixing process is mainly controlled by a slow diffusion mechanism. The fluid flow is also in two or multi-phases with droplets. The mixing processes are usually carried out by an applied external force, such as electric, thermal, magnetic, or acoustic. The topic of two or multi-phase and/or multicomponent flows is a very challenging task, computationally. Most analysis has been based on empirical correlations and non-exact science. Moreover, the fluid-structure interaction on micro- and nano-scales is not fully understood. The problem becomes more challenging with extra physics, such as electrical force, Joule heating, unsteady flows, etc. Hence, there is a need to understand and develop solid underlying physics of the problem and develop a mathematical model for simulations of those devices.***The simulation results help us to understand the physics and the effects of the controlling parameters. Also, simulation is cost effective in the optimization process of such devices. Conventional CFD methods have many limitations when it comes to dealing with multi-phase flows. On the other hand, the Lattice Boltzmann method (LBM) is a very powerful alternative method compared with the conventional methods to solve fluid dynamics problems. In LBM, it is relatively easy to integrate thermodynamics with transport equations. Besides, it enjoys simple coding and can be easily used with parallel processor computers. The outcome of the research will help in developing novel, reliable and real-time, droplet-based microfluidic devices for many applications. The outcomes will contribute to the Canadian economy.