@article { author = {Shirazpoor, S. and Kolahdoozan, M.}, title = {Applying Turbulent Flow Characteristics to the Multi-Phase MPS Method}, journal = {Journal of Hydraulics}, volume = {7}, number = {2}, pages = {1-11}, year = {2012}, publisher = {Iranian Hydraulic Association}, issn = {2345-4237}, eissn = {2645-8063}, doi = {10.30482/jhyd.2013.15750}, abstract = {The purpose of this paper is to put forward a new method of Multi-phase Moving Particle Semi-implicit (MP-MPS) for solving continuity and momentum equations of viscous fluid flow. MP-MPS is a Lagrangian meshless method that solves the governing differential equations of gas, fluid and solid phases, simultaneously. This method has many applications in problems of free surface flow which is due to their complex conditions and non-linear equations. Among these complexities is the need to consider the effect of turbulence. Until now, MPS method has been used widely for inviscid fluids or those with constant eddy viscosity. In this paper, the effect of turbulence closure model is investigated using Prandtl’s mixing-length theory. The enhancement of MPS model in estimating free surface flow considering the effect of turbulence is demonstrated through comparing its results with those of fluid with constant eddy viscosity and inviscid fluid for a typical dam break problem. The results obtained from the developed model show that determination of eddy viscosity of each particle in each time step based on their location and velocity is important and has a major effect on the final hydrodynamic parameters computations. In addition, results obtained through the improvement made in the numerical model have a good degree of similarity with those obtained through experiments. Also, the results indicate that applying the turbulence nature of the flow helps in obtaining a more stable solution and therefore in this case, the type of Kernel function used in MPS method has no significant effect on its stability. }, keywords = {hydrodynamic,Lagrangian,Turbulence,Prandtl’s Mixing Length,MPS method,Free surface}, title_fa = {اعمال خصوصیات جریانهای آشفته در روش MPS چند فازی}, abstract_fa = {- محاسبات مربوط به جریان با حل معادله‌های مومنتم و پیوستگی انجام می‌شود. یکی از روش‌های حل این معادله‌ها در مسائل با سطح آزاد متحرک به دلیل شرایط پیچیده و امکان برخورد سطوح آزاد با یکدیگر روش MPS چند فازی است. این روش یک روش لاگرانژی است که ابری از ذرات جایگزین شبکه محاسباتی می‌شوند و در حالت چند فازی معادله‌های حاکم بر چند فاز گاز، مایع و جامد به صورت همزمان حل می‌شوند. در این مقاله اثر اعمال آشفتگی با مدل صفر معادله‌ای در روش MPS مطالعه شده است. نتایج حاصل از این تحقیق حاکی از افزایش پایداری روش و بهبود برآورد سطح آزاد در مسأله شکست سد در مقایسه با حالت غیرلزج و با لزجت گردابه‌ای ثابت است. همچنین ارتقای مدل بوسیله اعمال مدل‌های آشفتگی در مدل چند فازی نشان‌دهنده عدم تأثیر نوع تابع کرنل مورد استفاده در حل معادلات مومنتم و پیوستگی بر روی پایداری روش می‌باشد.}, keywords_fa = {hydrodynamic,Lagrangian,Turbulence,Prandtl’s Mixing Length,MPS method,Free surface}, url = {https://jhyd.iha.ir/article_15750.html}, eprint = {https://jhyd.iha.ir/article_15750_217c50fdf49d2e3c04448e5bd2e2460e.pdf} }