Simulation of Torricelli Effluent Flow by Using Visual Basic for Application (VBA) on Microsoft Excel

摘要

Simulation of Torricelli effluent flow was created by using Visual Basic for Application (VBA) on Microsoft Excel. It describes a container with a cross sectional area A_1 filled by water with a certain level h_1. At the container's wall, there is a small leakage with a leakage height h2 and a cross sectional area A_2. If the quantity of water in the container is very large (A_1 A_2), the speed of water is constant, and the effluent distance of water out from leakage (x) can be simply determined by applying the Bernoulli principle, the equation of continuity, and the formula of free-fall motion. However, if the cross sectional area of container is proportional to the leakage's cross sectional area, then the speed of effluent water decreases with time and the formula of effluent distance is revisited. The simulation program was generated by the Euler method and analytical calculation. The manipulated variables are water level, leakage height, buffer height, container cross sectional area, and leakage cross sectional area. The simulation presents idealized condition by ignoring the air resistance, adhesion force, and surface tension of water so that it deviates from experimental results.