Spreadsheet analysis of the field-driven start-up flow in a microfluidic channel.

We discuss, in this article, the solution method of the unsteady electroosmotic flow of Newtonian fluid in a square microfluidic channel cross-section in the framework of spreadsheet analysis. We demonstrate the implementation of the finite difference scheme, which is used for the discretization of the transport equations governing the flow dynamics of the present problem, in the spreadsheet tool. Also, we have shown the implementation details of different boundary conditions, which are typically used for the underlying electrohydrodynamics in a microfluidic channel, in the spreadsheet analysis tool. We show that the results obtained from the spreadsheet analysis match accurately with the numerical solutions for both the electrostatic potential distribution and the flow velocity. Our results of this analysis justify the credibility of the spreadsheet tool for capturing the intricate details of the electrically actuated microflows during the initial transiences, that is, for the start-up flows and the phenomenon due to the electrical double layer effect, quite effectively. The inferences of this analysis will open up a new research paradigm of microfluidics and microscale transport processes by providing the potential applicability of the spreadsheet tools to obtain the flow physics of our interest in a very intuitive and less expensive manner.