Four multiphase flow models or correlations (Duns & Ros, Hagedorn & Brown, Orkiszewski, and Beggs & Brill) are currently available in Hydra for predicting the pressure profile in a well. The range of applicability of the multiphase flow models is dependent on several factors such as, tubing size or diameter, oil gravity, gas-liquid ratio, and, two-phase flow with or without water-cut. The effec...

This review deals with the theory of multiphase media in astrophysical systems. I discuss the basic reasons for the existence of multiple thermal phases, and the fundamental connection between multiphase media and thermal instability. After describing important examples of multiphase media, I examine the interactions among phases, i.e., mass exchange driven by thermal conduction and hydrodynami...

Our understanding of multiphase physics and the associated predictive capability for multiphase systems are severely limited by current continuum modeling methods and experimental approaches. This research will deliver an unprecedented modeling capability to directly simulate three-dimensional multiphase systems at the particle-scale. The model solves the fully coupled equations of motion gover...

We discuss here current computational trends (beyond Mechanistic 1D Models) related to transient multiphase flow and flow assurance problems in the oil and gas sector. The developments needed to bring advanced Computational fluid &Multiphase-fluid dynamics (CFD&CMFD) techniques and models to a mature stage will also be discussed. The contribution presents the possibilities offered today by thes...

We apply the Piecewise Constant Level Set Method (PCLSM) to a multiphase motion problem, especially the pure mean curvature motion. We use one level set function to represent multiple regions, and by associating an energy functional which consists of surface tension (proportional to length), we formulate a variational approach for the mean curvature motion problem. Some operator-splitting schem...

We study the problem of intergenerational equity for utility streams and a countable set of agents. A numerical social welfare function is invariant to ordinal transformation, satis…es a weak monotonicity condition, and an invariance with respect to concatenation of utility streams if and only if it is either the sup, inf, lim sup, or lim inf.

The paper is designated to the analysis of queueing systems, arising in the network theory and communications theory (called multiphase queueing systems, tandem queues or series of queueing systems). Also we note that multiphase queueing systems can be useful for modelling practical multi-stage service systems in a variety of disciplines, especially on manufacturing (assembly lines), computer n...

Let b k := (C 2 A)(M b;k), then lim k!1 a k = lim k!1 b k. The proof is complete. 2 From the preceding lemmas, we obtain the following theorem. As fhg ? ; M k(m) ig is a Cauchy sequence, hg ? ; M m;1 i 0 hg ? ; M k(m) i ! 0 (as m ! 1): We obtain that lim m!1 b m = lim m!1 a k(m). The proof is complete. 2 Lemma 23 We obtain Proof It suces to prove that for a Cauchy sequence fa k g F such that li...

We propose a computational method with no ad hoc empirical parameters to determine the elastic properties of multiphase composites of complex geometries by numerically solving the stress–strain relationships in heterogeneous materials. First the randommicrostructure of the multiphase composites is reproduced in our model by the random generation-growth method. Then a high-efficiency lattice Bol...