ANALYSIS OF REAL FLUID FLOW IN PLANAR NETWORKS PROFILES

Autor/autori: Mariana VODA (TODIRUTA)

Rezumat: Lucrarea de fata,are ca scop analiza curgerii in retele de profile plane, pentru determinarea marimilor specifice primare (viteza, presiune) si globale (forta, cadere, randament). Curgerea studiata, este o curgere intr-o retea mobila de profile hidrodinamice (turbina). Pentru acest studiu s-a ales profilul hidrodinamic NACA 8410 dispus intr-o retea dreapta de profile, cu un unghi de instalare de 40o si unghiul de intrare de 50o. Pasul relativ al retelei este de 1,2 m iar domeniul de analiza este bidimensional 2D, cu profilul inglobat in banda de periodicitate. Pentru discretizarea domeniului de analiza s-a ales o retea structurata cu 36.626 elemente patrulatere. S-a efectuat simularea numerica pentru curgerea fluidului incompresibil vascos, in regim nestationar pentru o viteza de transport U de 8,2 m/s. Se analizeaza fenomenul de curgere si se pun in evidenta parametrii ce influenteaza curgerea, prin solutionarea numerica a ecuatiilor ce guverneaza curgerea fluidului in echipamente hidraulice utilizand programul pentru simularea curgerii fluidelor FLUENT6.3. Pentru definirea domeniului de analiza (2D), a conditiilor de periodicitate, discretizarea si definirea conditiilor de frontiera, s-a utilizat programul de preprocesare GAMBIT. Rezultatele obtinute au fost sub forma numerica, si au fost postprocesate grafic si calculate marimi derivate din cele obtinute in etapa de solutionare numerica. In urma interpretarii rezultatelor obtinute s-a ajuns la concluzia de baza ca marimile hidrodinamice specifice, primare si globale determinate prin metoda simularii numerice, rezultatele numerice obtinute sunt valide in concordanta cu fenomenul real studiat. Din distributia de presiune statica, rezulta ca incidenta curentului pe profil este buna. De aceea randamentul este ridicat.

Cuvinte cheie: fluid real, retea de profile, coeficient de presiune, simulare numerica

Abstract: This paper aims to analyze the flow in planar networks profiles to determine the specific primary quantities (velocity, pressure) and global (force, dropping, efficiency). Studied flow is a flow in a mobile network of hydrodynamic profiles (turbine). For this study we chose the NACA 8410 hydrodynamic profile arranged in a straight network, with an installation angle of 40 ° and 50° entrance angle. Relatively step of the network is 1.2 m and the analysis domain is 2D, with the profile embedded in the periodicity band. For meshing domain analysis was chosen a structured grid with 36.626 quadrilateral elements. Numerical simulation was performed for incompressible viscous fluid flow in unsteady regime for U transport velocity of 8.2 m / sec. It analyzes the phenomenon of flow, and highlight parameters which influencing the flow by numerically solving of the equations that govern the fluid flow in hydraulic equipment using the numerical simulation program FLUENT6.3. To define the 2D analysis domain, periodicity conditions, meshing and defining boundary conditions was used GAMBIT preprocessing program. The results obtained were in numerical form, and were post-processed graphically and calculated quantities derived from the numerical solution. Following the interpretation of the results obtained we concluded that specific hydrodynamic sizes, global and primary, determined by the numerical simulation, the results are valid according to the real phenomenon studied. From the static pressure distribution, it is clear that the incidence of the current profile is good. Therefore the efficiency is high

Keywords: real fluid, profiles network, pressure coefficient, numerical simulation

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