Washed Off The Toilet Flushing Process Of Gas-liquid Multiphase Flow Numerical Simulation And Experimental Study

In China, water shortage is highly serious and the quantity per capita is only a quarter of the world average. As the increasing of population, updating of living standard and urbanization, the amount of living water will rapidly go up. Therefore, the developing, popularizing and using of water-saving toilets are important and significant to deal with water shortage.The maximum 6-litre flush volume requirement, which has been enforced in developed countries, has not been implemented at home. The primary reason is that the development, design and tool of toilets are still made manually. The quality of new products depends entirely on the experience of the workers. So, it is difficult for the traditional manual way to develop and design quality-high and water-saving toilets.As the rapid development of computer technology and numerical calculation technique, the method of Computational Fluid Dynamics (CFD) has flourished as well, which opens a new way to develop and design quality-high and water-saving toilets. When the method of CFD is applied to simulate the flushing process of toilets, the distribution of flow, pressure and velocity would be gained conveniently and intuitively. Such results can be used to develop and design new products, greatly shortening development time, saving development cost, and improving product quality. Therefore, the method of CFD is the key to upgrade the toilets, getting more and more attention.The types of toilets include wash-down type and siphon type. In this paper, a wash-down toilet is studied. The purpose is to set up a numerical solution to simulate the flush process of toilets. Firstly, based on the physical model of the flush process of wash-down toilets, the CFD software FLUENT is selected and the simulation scheme is developed. At the same time, some experiments are carried out to validate the veracity of simulation result. The main research includes:(1) After analyzing the characteristic of flush process and introducing the concept of ordure equivalent, the corresponding physical model is set up and simplified as a three-dimension unsteady multi-phase flow with free surface.(2) On the base of the multi-phase model—Volume of Fluid— in FLUENT, the...