Numerical Modeling of Pressure drop due to Single - phase Flow of Water and Two - phase Flow of Air - water Mixtures through Thick Orifices

  ijett-book-cover  International Journal of Engineering Trends and Technology (IJETT)          
  
© 2012 by IJETT Journal
Volume-3 Issue-4                          
Year of Publication : 2012
Authors :  Manmatha K. Roul , Sukanta K. Dash

Citation 

Manmatha K. Roul , Sukanta K. Dash. "Numerical Modeling of Pressure drop due to Single - phase Flow of Water and Two - phase Flow of Air - water Mixtures through Thick Orifices". International Journal of Engineering Trends and Technology (IJETT). V3(4):544-551 Jul-Aug 2012. ISSN:2231-5381. www.ijettjournal.org. published by seventh sense research group.

Abstract

Pressure drops through thick orifices have been numerically inve stigated with single phase flow of water and two - phase flow of air – water mixtures in horizontal pipes. Two - phase computational fluid dynamics (CFD) calculations, using Eulerian – Eulerian model have been employed to calculate the pressure drop through orific es. The operating conditions cover the gas and liquid superficial velocity ranges V sg = 0.3 – 4 m/s and V sl =0.6 – 2 m/s, respectively. The local pressure drops have been obtained by means of extrapolation from the computed upstream and downstream linearized pressure profiles to the orifice section. Simulations for the single - phase flow of water have been carried out for local liquid Reynolds number ranging from 3×10 4 to 2×10 5 to obtain the discharge coefficient and two - phase local multiplier. The effect of or ifice geometry on two - phase pressure losses has been considered by selecting two pipes of 60 mm and 40 mm inner diameter and four different orifice plates (for each pipe) with two area ratios ( ? = 0.73 and ? = 0.54) and two different orifice thicknesses ( s / d = 0. 025, 0.59). The results obtained from numerical simulations are validated against experimental data from the literature and are found to be in good agreement

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Keywords
orifice, pressure drop, two phase flow, area ratio, discharge coefficient, two - phase multiplier.