Computational Study of the Dynamics of the Flow in a Gravity-Driven Toilet

Nowadays, strong efforts are focused in achieving a rational use of water due to the low amount of accessible and available water in the world. Toilets are essential elements that represent a significant percentage of the water consumption in the domestic sector. Any improvement in these devices signifies an important reduction in the water demand. Additionally, regarding the Colombian industry, the toilet design process takes up to one year and it is a totally empirical process. In this document a Computational Fluid Dynamics (CFD) model of a gravity driven toilet flush is presented. First, a base case was implemented with some important assumptions and simplifications, such as the omission of some geometric details and the discharge valve. Then, characterization curves of pressure, mass flow rate and turbulence intensity magnitude in different parts of the toilet are presented. Moreover, a basic experimental comparison of the water mass flow rate at the toilet outlet was done achieving satisfactory results. Finally, the influence of the Coriolis phenomenon in the performance of the toilet was studied.