Bifurcating channels supplying “numbered-up” microreactors

► Simplified theory of branching reactants flow into microreactors on a microchip. ► Channels made by isotropic etching occupy much of the surface area. ► Evaluation uses a two-parametric model, with widths of channels and sealing strips as variables. This study is intended to be the starting point for theory of branching channels that supply reactants into chemical microreactors positioned on the surface of a microchip. The channels are assumed to be made by isotropic etching – and therefore of the same depths everywhere, irrespective of their cross-section area. When required to handle larger flows, the channels are therefore wide and thus occupy a substantial proportion of the available surface area. Because of the intended starting-point character, this discussion of the branchings assumes the simplest, isokinetic bifurcation. The branching pattern may resemble the self-similar pattern of fractal objects, but the constant depth makes the fractal theory inadequate. The evaluation of the chip surface areas occupied by the three basic components of the system – the reactors, the sealing strips, and the channels – uses a two-parametric model, with widths of the channels and sealing strips as the independent variables.