We are concerned with robust and accurate forecasting of multiphase flow rates in wells and pipelines during oil and gas production. In practice, the possibility to physically measure the rates is often limited; besides, it is desirable to estimate future values of multiphase rates based on the previous behavior of the system. In this work, we demonstrate that a Long Short-Term Memory (LSTM) re...

Cavitation is an intricate multiphase phenomenon that interplays with turbulence in fluid flows. It exhibits clear duality in characteristics, being both destructive and beneficial in our daily lives and industrial processes. Despite the multitude of occurrences of this phenomenon, highly dynamic and multiphase cavitating flows have not been fundamentally well understood in guiding the effort t...

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...

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...

background methotrexate is a folic acid antagonist that has been in clinical use for five decades. its use in patients with brain tumors is primarily confined to primary central nervous system lymphoma (pcnsl), in which it is the cornerstone of chemotherapy. objectives a selective and sensitive high-performance liquid chromatography-electrospray ionization-mass spectrometry method was developed...

since its introduction in 1988, laparoscopic cholecystectomy (lc) has become the procedure of choice in the management of gallstone disease. it has well established advantages compared to its traditional open counterpart such as reduction in hospital stay and related costs, more rapid return to work, and reduction in pain and cosmetic problems. lc, like any other procedure, has its own indicati...