DIRECT SIMULATION BASED MODEL-PREDICTIVE CONTROL OF FLOW MALDISTRIBUTION IN PARALLEL MICROCHANNELS

摘要

The goal of this investigation is to develop a simulation-based control strategy to eliminate flow-maldistribution in parallel microchannels. An accurate simulation of fluid flow through parallel microchannels is achieved by utilizing a fictitious domain representation of immersed objects, such as microvalves and bubbles. System identification techniques are employed to produce a lower dimensional model that captures the essential dynamics of the full nonlinear flow, in terms of a relationship between the valve angles and the exit flow rate for each channel. The resulting linear model is incorporated into a model predictive control scheme to identify flow maldistribution from exit flow velocities and prescribe actuation of channel valves to effectively redistribute the flow. Flow simulations in a three parallel mi-crochannel geometry including bubbles illustrates the effectiveness of the control design, which quickly and efficiently varies channel valves to remove the bubble and equalize the flow rates in each channel.