Abstract
In many microreactors, reactant flows are first split into many lamination segments and then fed into the reactors. We studied influences of design factors such as arrangements, aspect ratio of rectangular cross section, and cross sectional shapes of fluid segments at the reactor inlet on progress of multiple reactions by using computational fluid dynamics (CFD) simulations. First, for the two segment arrangements, the side length of square cross section of segments that gives the same maximum yield of the desired product was derived. To obtain the same maximum yield of the desired product, the alignment of segments in a line required smaller segments than the arrangement to two dimensional directions. The ratio of contact surface area between segments to reactor volume for each arrangement is different even if the maximum yields of the desired product for both arrangements are the same. Second, influences of aspect ratio of rectangular cross section of segments were studied. The mixing efficiency was improved with increase in the aspect ratio when the cross sectional area of the segment for every aspect ratio is fixed. The direction that has the shorter diffusion length greatly affects the mixing efficiency. Finally, the influences of cross sectional shapes of segments on progress of multiple reactions were studied. Shapes that have larger ratio of contact surface area between segments to reactor volume provide higher mixing efficiency. The results also showed that the ratio of contact surface area between segments to reactor volume that gives a certain maximum yield of the desired product and progress of the multiple reaction depend on cross sectional shapes. The results in this study indicated that microreactors have a very fair possibility of controlling yield and selectivity of desired products for multiple reactions by properly designing segments arrangements and shapes.
