Relevant bibliographies by topics / Liquid entry pressure

Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Book chapters
  4. Conference papers

Academic literature on the topic 'Liquid entry pressure'

Author: Grafiati
Published: 10 January 2023
Last updated: 28 January 2023

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Liquid entry pressure.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Liquid entry pressure"

1

Claramunt, Sara, Florian Völker, Uta Gerhards, Manfred Kraut, and Roland Dittmeyer. "Membranes for the Gas/Liquid Phase Separation at Elevated Temperatures: Characterization of the Liquid Entry Pressure." Membranes 11, no. 12 (November 23, 2021): 907. http://dx.doi.org/10.3390/membranes11120907.

Full text
Abstract:
Hydrophobic membranes were characterized at elevated temperatures. Pressure was applied at the feed and permeate side to ensure liquid phase conditions. Within this scope, the applicability of different polymeric and ceramic membranes in terms of liquid entry pressure was studied using water. The Visual Method and the Pressure Step Method were applied for the experimental investigation. The results show the Pressure Step Method to be an early detection method. The tests at higher pressure and temperature conditions using the Pressure Step Method revealed the temperature as being the main factor affecting the liquid entry pressure. Novel LEP data up to 120 °C and 2.5 bar were obtained, which broadens the application range of hydrophobic membranes.
APA, Harvard, Vancouver, ISO, and other styles
2

Yazgan-Birgi, Pelin, Mohamed I. Hassan Ali, and Hassan A. Arafat. "Estimation of liquid entry pressure in hydrophobic membranes using CFD tools." Journal of Membrane Science 552 (April 2018): 68–76. http://dx.doi.org/10.1016/j.memsci.2018.01.061.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Matsumura, Kunihito, and Fumito Kaminaga. "Experimental Investigation of Rising Gas Bubble Characteristics from a Vertical Tube under CCFL Condition." Science and Technology of Nuclear Installations 2012 (2012): 1–15. http://dx.doi.org/10.1155/2012/785157.

Full text
Abstract:
This paper describes an experimental study of gas/liquid countercurrent flow in a vertical circular tube. CCFL experiments were carried out with three different water levels in the upper plenum, two different tube diameters. Measurements were made for liquid and gas flow rates, time variations of pressure at locations of the upper entry of the tube and lower plenum. Visual observations were also conducted to investigate the relationship between rising gas bubble characteristics and time variation of gas pressure at the upper entry of the tube. The results indicate that one bubble formation cycle (e.g., bubble growth, expansion, and detachment into the water pool) corresponds to one pressure fluctuation cycle. For the 20 mm diameter tube, it was confirmed that there was a characteristic waiting time between bubble cycles in which no bubble was formed at the upper entry of the tube. The waiting time is a favorable time for a liquid introduction into the tube from the upper plenum. The bubble volumes are compared with existing bubble formation correlations.
APA, Harvard, Vancouver, ISO, and other styles
4

Park, Chansoo, Dongsoo Shin, Chang-Kyu Lee, Yong-Soo Lee, and Jong-Oh Kim. "Theoretical and experimental approaches of liquid entry pressure determination in membrane distillation processes." DESALINATION AND WATER TREATMENT 99 (2017): 172–76. http://dx.doi.org/10.5004/dwt.2017.21653.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Rácz, Gábor, Steffen Kerker, Zoltán Kovács, Gyula Vatai, Mehrdad Ebrahimi, and Peter Czermak. "Theoretical and Experimental Approaches of Liquid Entry Pressure Determination in Membrane Distillation Processes." Periodica Polytechnica Chemical Engineering 58, no. 2 (2014): 81–91. http://dx.doi.org/10.3311/ppch.2179.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Chamani, Hooman, Pelin Yazgan-Birgi, Takeshi Matsuura, Dipak Rana, Mohamed I. Hassan Ali, Hassan A. Arafat, and Christopher Q. Lan. "CFD-based genetic programming model for liquid entry pressure estimation of hydrophobic membranes." Desalination 476 (February 2020): 114231. http://dx.doi.org/10.1016/j.desal.2019.114231.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

FALTINSEN, ODD M., and YURIY A. SEMENOV. "Nonlinear problem of flat-plate entry into an incompressible liquid." Journal of Fluid Mechanics 611 (September 25, 2008): 151–73. http://dx.doi.org/10.1017/s0022112008002735.

Full text
Abstract:
The self-similar flow and free-surface shape induced by a flat plate entering an inviscid and incompressible liquid are investigated for arbitrary initial conditions. An analytical solution, which is based on two governing expressions, namely the complex velocity and the derivative of the complex potential, is obtained. These expressions are derived in an auxiliary parameter plane using integral formulae proposed for the determination of an analytical function from its modulus and argument given on the boundary of the parameter region. We derive a system of an integral and an integro-differential equation in terms of the velocity modulus and the velocity angle at the free surface, which are determined by the dynamic and kinematic boundary conditions. A numerical procedure for solving these equations is carefully validated by comparisons with results available in the literature. The results are presented in terms of the free surface shape, the angles at the tip of the splash jet, the contact angles at the intersection with the plate surface, pressure distribution and force coefficients. New features caused by the flow unsteadiness are found and discussed.
APA, Harvard, Vancouver, ISO, and other styles
8

Wang, Yajun, Jun Yang, Manchao He, Xichun Tian, Jianning Liu, Haojie Xue, and Ruifeng Huang. "Test of a liquid directional roof-cutting technology for pressure-relief entry retaining mining." Journal of Geophysics and Engineering 16, no. 3 (June 1, 2019): 620–38. http://dx.doi.org/10.1093/jge/gxz041.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Racz, Gabor, Steffen Kerker, Oliver Schmitz, Benjamin Schnabel, Zoltan Kovacs, Gyula Vatai, Mehrdad Ebrahimi, and Peter Czermak. "Experimental determination of liquid entry pressure (LEP) in vacuum membrane distillation for oily wastewaters." Membrane Water Treatment 6, no. 3 (May 25, 2015): 237–49. http://dx.doi.org/10.12989/mwt.2015.6.3.237.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

García-Payo, M. C., M. A. Izquierdo-Gil, and C. Fernández-Pineda. "Wetting Study of Hydrophobic Membranes via Liquid Entry Pressure Measurements with Aqueous Alcohol Solutions." Journal of Colloid and Interface Science 230, no. 2 (October 2000): 420–31. http://dx.doi.org/10.1006/jcis.2000.7106.

Full text
APA, Harvard, Vancouver, ISO, and other styles
More sources

Dissertations / Theses on the topic "Liquid entry pressure"

1

Moghadam, Ali. "Capillary Forces in Partially Saturated Thin Fibrous Media." VCU Scholars Compass, 2019. https://scholarscompass.vcu.edu/etd/6110.

Full text
Abstract:
Capillarity is often exploited in self-cleaning, drag reducing and fluid absorption/storage (sanitary products) purposes just to name a few. Formulating the underlying physics of capillarity helps future design and development of optimized structures. This work reports on developing computational models to quantify the capillary pressure and capillary forces on the fibrous surfaces. To this end, the current study utilizes a novel mass-spring-damper approach to incorporate the mechanical properties of the fibers in generating virtual fibrous structures that can best represent fibrous membranes. Such virtual fibrous structures are then subjected to a pressure estimation model, developed for the first time in this work, to estimate the liquid entry pressure (LEP) for a hydrophobic fibrous membrane. As for accurate prediction (and not just estimation) of the capillary pressure, this work also presents an energy minimization method, implemented in the Surface Evolver code, for tracking the air–water interface intrusion in a hydrophobic fibrous membrane comprised of orthogonally oriented fibers. This novel interface tracking algorithm is used to investigate the effects of the membrane’s microstructure and wetting properties on its resistance to water intrusion (i.e., LEP). The simulation method developed in this work is computationally affordable and it is accurate in its predictions of the air–water interface shape and position inside the membrane as a function of pressure. Application of the simulation method in studying effects of fiber diameter or contact angle heterogeneity on water intrusion pressure is reported for demonstration purposes. Capillary forces between fibrous surfaces are also studied experimentally and numerically via the liquid bridge between two parallel plates coated with electrospun fibers. In the experiment, a droplet was placed on one of the polystyrene- or polyurethane-coated plates and then compressed, stretched, or sheared using the other plate and the force was measured using a sensitive scale. In the simulation, the liquid bridge was mathematically defined for the Surface Evolver finite element code to predict its 3-D shape and resistance to normal and shearing forces, respectively, in presence of the contact angle hysteresis effect. Despite the inherent non-uniformity of the fibrous surfaces used in the experiments and the simplifying assumptions considered for the simulations, reasonable agreement was observed between the experiments and simulations. Results reveal that both normal and shear force on the plates increase by increasing the liquid volume, or decreasing the spacing between the plates.
APA, Harvard, Vancouver, ISO, and other styles
2

Bouainouche, Mokrane. "Etude de l'interaction entre un jet plan à grande vitesse et un film liquide." valenciennes, 1995. https://ged.uphf.fr/nuxeo/site/esupversions/2f38b9a7-3e25-4c6f-968e-e4d2d3c14d4a.

Full text
Abstract:
La première partie de l'étude s'intéresse à la modélisation de l'impact d'un jet de gaz plan et mince sur une paroi plane en vue d'en déduire les distributions de pression et de contrainte de cisaillement sur la paroi. Dans la deuxième partie, ces résultats sont utilisés pour étudier le comportement d'un film liquide visqueux entraîné par le déplacement vertical d'une bande et soumis à l'action d'un jet. Les actions du jet sur la surface sont déterminées par un calcul numérique en utilisant un schéma de type volume fini. L’écoulement d'un jet bidimensionnel, turbulent et compressible sur une plaque plane est modélisé en utilisant le modèle de turbulence k- avec des fonctions de paroi. Pour réduire l'influence du maillage près de la paroi sur le calcul de la contrainte de cisaillement pariétale, une loi de paroi hybride est proposée en utilisant simultanément la loi de paroi logarithmique et sa forme généralisée. Les distributions de pression et de contrainte de cisaillement sont calculées et validées par des mesures expérimentales. L’équation du mouvement du film liquide est écrite en considérant le terme d'accélération, négligé dans les études précédentes. Le modèle est appliqué a un processus de galvanisation et validé par des résultats expérimentaux obtenus dans des conditions diverses
The first part of this study deals with the modelling of the impact of a thin plane gas jet a flat plate in order to define the pressure and shear stress distributions on the wall. In the second part, these results are used to study the behavior of viscous film liquid on the strip moving upward and submitted to the jet action. The jet actions are determined by a numerical computation based on finite volume scheme. The impingement of a plane two dimensional turbulent and compressible jet is modelised using the k-ɛ model combined to the wall functions. In order to reduce the near wall gnd influence on the shear stress calculation, a hybrid wall law is proposed resulting from simultaneous use of the logarithmic law and generalized one. Pressure and shear stress distributions on the flat plane are calculated and validated by experimental data. The motion of liquid coating is modelised by taking into account the inertia terms, neglected in the previous studies. This model is applied to the galvanization process and compared with measurements obtained in various conditions
APA, Harvard, Vancouver, ISO, and other styles
3

Bertin, Nicolas. "Déformations d'interfaces liquides guidantes par la pression de radiation acoustique et optique." Thesis, Bordeaux 1, 2011. http://www.theses.fr/2011BOR14266/document.

Full text
Abstract:
Ces travaux sont consacrés à l'étude de la déformation d'interfaces liquides planes par la pression de radiation acoustique. Deux configurations expérimentales sont étudiées, selon que la vitesse du son du liquide d'où vient l'onde est plus grande ou plus petite que la vitesse du son de la seconde phase liquide. Ces travaux de recherche fondamentale ont pour objectif de comprendre les différentes formes complexes observées : jets, déformations en forme de doigts, tétines. Cela est rendu possible par le développement d'un modèle de couplage entre la propagation de l'onde et la déformation de l'interface. Ce modèle est notamment utile pour la compréhension et la caractérisation de colonnes liquides à la fois créées et stabilisées par la pression de radiation acoustique. Pour chacune des études, un parallèle est fait entre les déformations d'interfaces par un faisceau ultrasonore focalisé et par un faisceau laser continu
Acoustic radiation pressure allows us to remotely create and manipulate liquid objets. Using a highly focused transducer, which emitted field is studied, we can create large aspect ratio and complex liquid interface deformations. This fundamental research aims at understanding these various objects. For this purpose, we developed a theoretical model taking into account the coupling between the wave propagation and the deformation of the interface. This model allows us to predict the characteristics of liquid columns both formed and stabilized by the acoustic radiation pressure. A study of acoustic liquid jets is performed as well. Moreover, we characterize finger-shaped andpacifier-shaped objects as piles of acoustic waveguides. The acoustic wave creates a liquidobject self-adapted to its propagation. For each of these studies, we compare deformationsobtained via the acoustic radiation pressure and the electromagnetic radiation pressurefrom a continuous laser beam
APA, Harvard, Vancouver, ISO, and other styles
4

Morais, Caroline Pinheiro Marques de. "Modelagem do Equilíbrio de Fases entre Hidrocarbonetos Leves e Pesados." Universidade do Estado do Rio de Janeiro, 2009. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=2706.

Full text
Abstract:
Agência Nacional do Petróleo
O comportamento de fases para sistemas binários com um hidrocarboneto leve e um pesado é muito importante tanto para o projeto real de um processo quanto para o desenvolvimento de modelos teóricos. Para atender a crescente demanda por informação experimental de equilíbrio de fases a altas pressões, o objetivo deste estudo é obter uma metodologia que substitua parcialmente ou maximize a pouca informação experimental disponível. Para isto propõe-se a modelagem do equilíbrio de fases em misturas de hidrocarboneto leve com um pesado, sem o conhecimento da estrutura molecular do pesado, inferindo-se os parâmetros do modelo a partir da modelagem de dados de ponto de bolha obtidos na literatura. Esta metodologia implica não só na descrição do equilíbrio de fases de um sistema como na estimação das propriedades críticas do pesado, de difícil obtenção devido ao craqueamento destes a altas temperaturas. Neste contexto, este estudo apresenta uma estratégia que estima indiretamente as propriedades críticas dos compostos pesados. Para isto, foram correlacionados dados experimentais de ponto de bolha de misturas binárias contendo um hidrocarboneto leve e um pesado, usando-se dois modelos: o de Peng-Robinson e o TPT1M (Teoria da Polimerização Termodinâmica de primeira ordem de Wertheim modificada). Os parâmetros ajustados com o modelo de Peng-Robinson correspondem diretamente às propriedades críticas do composto pesado, enquanto os ajustados com o modelo TPT1M foram usados para obtê-las. Esta estratégia fornece parâmetros dependentes do modelo, porém permite o cálculo de outras propriedades termodinâmicas, como a extrapolação da temperatura dos dados estudados. Além disso, acredita-se que a correlação dos parâmetros obtidos com as propriedades críticas disponíveis ajudará na caracterização de frações pesadas de composição desconhecida
The phase behavior of binary systems with a light hydrocarbon and a heavy one is very important both for the design of a process and the development of theoretical models. To meet the growing demand for information from experimental phase equilibria at high pressures, this study aims to obtain a methodology to replace partially or maximize the little experimental data available. Therefore it is proposed to model the phase equilibria in hydrocarbon mixtures with a heavy compound, without the knowledge of its molecular structure, inferring the model parameters from the data modeling of bubble point from the literature. This methodology involves not only the description of phase equilibrium of a system as the estimation of critical properties of heavy hydrocarbons, difficult to obtain due to its cracking at high temperatures. In this context, this work presents a strategy that indirectly estimates critical properties of heavy compounds. Here, bubble point experimental data of binary mixtures containing a light HC and a heavy one are correlated by using a TPT1 (Wertheims first order thermodynamic polymerization theory) model of freely joined tangent spheres employing the square-well potential with variable well width as segment interaction potential. The fitted parameters are used in order to obtain the heavy compound critical properties. The Peng-Robinson model was also used for comparison. This strategy provides model dependent parameters, but allows the calculation of other thermodynamic properties, i.e. temperature extrapolation of the studied data. Besides, the correlation of the obtained parameters with available critical properties will help in the characterization of the heavy fractions
APA, Harvard, Vancouver, ISO, and other styles
5

Lin, Hung-Chia, and 林弘家. "A study on the measurement of membrane liquid entry pressure and simulation of tubular direct contact membrane distillation." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/95904339493743920406.

Full text
Abstract:
碩士
中原大學
化學工程研究所
102
Water scarcity is a growing problem to be faced by the World. In recent years, many attentions have been payed the problem by applying membrane distillation for desalination. Hydrophobic and porous membranes were used for membrane distillation processes, however, when a large hydraulic pressure over the so called liquid entry pressure (LEP), the membranes will be wetted and the feed side solution will directly pass through the membrane to the permeate side. To estimate or measure the liquid entry pressure (LEP) of membranes is important for membrane characterization and module design for membrane distillation. First part of this study, the LEP of different membranes were measured and compared with the predicted value from Laplace Equation. Experimental results showed that the LEP decreases obviously with the increase of feed temperature, for example, LEP decreased from 4 bar to 2.8 bar for 0.2 m PTFE membrane with solution temperature from 25 ℃ increased to 70 ℃. The measured LEP values were in a range of 150 to 200 % smaller than that estimated by Laplace(Cantor) equation based on cylindrical pore structure. Dividing the measured LEP by the estimated LEP, the geometrical parameter, B, in Laplace equation for the membranes used in the study were also evaluated. Second part of this study aimed to analyze the effects of tubular modules characteristics such as length, tubular diameter, packing density and membrane thickness etc. on the DCMD performance theoretically and experimentally. The simulation program was first confirmed by IV comparing the simulated flux to the measured data in literatures, both differences being in 5% to 20% range. Four different tubular membranes were assembled to module for DCMD experiments with countercurrent flow in the study. Comparison between experimental fluxes and that from simulation showed a difference in a range from 5 to 15%. This study also used the program to simulate the effects of module length, module packing density and membrane thickness on DCMD flux and energy efficiency. Simulated results showed that the average flux drops with increasing tubular membrane length, and there is a critical length of tubular membrane over which the average flux decline is slight due to the local temperature difference acrose the membrane decrease obviously only in the axial distance near the hot feed inlet. With respect to the effect of packing density on DCMD at a fixed feed rate, simulated results indicated that the flux decreased with increasing packing density. Finally, we analyzed the effect of membrane thickness on DCMD flux and a critical thickness about 30~40 m for the conditions used in the study was suggested. The flux increases with increasing membrane thickness when the thickness smaller than the critical value and then the flux decreases as the thickness larger than the critical thickness.
APA, Harvard, Vancouver, ISO, and other styles
6

Gao, Li. "Theoretical and Experimental Investigations of Permeate Gap Membrane Distillation." Thesis, 2019. https://vuir.vu.edu.au/40061/.

Full text
Abstract:
Membrane Distillation (MD) is a separation process driven by the vapour pressure difference established across hydrophobic membrane. In order to combine the advantages of conventional MD configurations, Permeate Gap Membrane Distillation (PGMD) modules were developed. The objectives of this study were to systematically evaluate the performance of several new hollow fibre PGMD modules. This study consisted of four components. First of all, the membrane was systematically characterized. The membrane dimension and morphology were investigated using Scanning Electron Microscope (SEM). The membrane porosity was measured using the wetting method. The membrane hydrophobicity was determined by measuring the contact angles of the inner and outer hollow fiber surfaces. Finally, Liquid Entry Pressure (LEP) was investigated. Based on the membrane characterization, it was confirmed that the employed hollow fibre membrane was suitable for MD application. Next, a single PGMD module was built with 8 gap channels and 1 hollow fibre within each gap channel. This module was operated in different modes (PGMD, DCMD and SGMD) to compare their performance. The results showed that the maximum flux of hollow fiber PGMD was 27% and 1.6% lower than the maximum flux of DCMD and SGMD respectively. This phenomenon was due to the higher coolant velocity for DCMD and applied air flow in the gap channel for SGMD. The mass transfer coefficient was also used as an indicator to compare performance. For PGMD, the mass transfer coefficient increased initially at the lower feed inlet temperature and then decreased when the feed inlet temperature was higher than 60˚C, which could be attributed to the combined effects of transverse vapor flux and temperature non-uniformity of the bulk flow. On the contrary, the global mass transfer coefficients of DCMD and SGMD decreased slightly as a function of feed inlet temperature. Compared to other studies, our results demonstrated that PGMD has the potential to effectively combine the advantages of different conventional MD processes. Afterwards, we have investigated the impacts of different PGMD module designs on water productivity and energy efficiency. The results showed that module with lower hollow fibre packing density or gap channel density had a higher flux and better energy efficiency, while modules with higher hollow fibre packing density or gap channel density exhibited more energy efficient use of the membrane surface area and higher productivity. Additionally, the module with a more conductive cooling plate had a higher flux and lower Specific Thermal Energy Consumption (STEC), which was mainly attributed to the lower thermal resistance of the cooling plate. Due to the nearly stagnant velocities within the gap and coolant channels, the impact of cooling plate material on PGMD performance was greater than that of hollow fibre packing density and gap channel density. The Gain Output Ratio (GOR) obtained for the hollow fibre PGMD module was relatively low compared to other MD studies, however, the PGMD module performance cannot be assessed purely based on GOR. A trade-off exists between GOR and flux for MD modules, and the flux obtained from our hollow fibre PGMD module was relatively high. Finally, a set of mathematical models were developed to simulate the mass and heat transfers phenomenon in hollow fibre PGMD process. The validated model was employed to evaluate the impacts of important MD design parameters on module performance. The modelling results showed that coolant velocity and coolant temperature had less impact on flux compared to those of DCMD, because the coolant of DCMD contacts with membrane directly. The model also suggested that increasing the cooling plate thermal conductivity resulted in a higher flux. However, when the cooling plate thermal conductivity was higher than 5 W/m.K, further increases in the thermal conductivity of the cooling plate had a negligible impact on flux. A sensitivity study was undertaken to analyze the combined effects of gap channel inner/outer diameters and gap channel thermal conductivity on flux. It is concluded that the gap thermal conductivity played a more important role in PGMD performance compared to the hydrodynamic flow in permeate and coolant channels. To further improve hollow fibre PGMD performance, six recommendations are provided for the future work.
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Liquid entry pressure"

1

Di Felice, Renzo. "Liquid Entry Pressure (LEP or LEPW)." In Encyclopedia of Membranes, 1105. Berlin, Heidelberg: Springer Berlin Heidelberg, 2016. http://dx.doi.org/10.1007/978-3-662-44324-8_1295.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Di Felice, Renzo. "Liquid Entry Pressure (LEP or LEPW)." In Encyclopedia of Membranes, 1. Berlin, Heidelberg: Springer Berlin Heidelberg, 2015. http://dx.doi.org/10.1007/978-3-642-40872-4_1295-1.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Aveyard, Bob. "Thin liquid films." In Surfactants, 314–36. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780198828600.003.0012.

Full text
Abstract:
The study of soap films, which are symmetrical, has a distinguished history. More recently, other asymmetric liquid films (e.g. pseudo-emulsion films and wetting films on solids) have been widely investigated. The (meta)stability of thin liquid films can be understood in terms of disjoining pressure isotherms, the shapes of which reflect the nature of the films. Film stability in systems with only fluids present can also be considered in terms of both classical and generalized entry coefficients, defined in terms of the various interfacial tensions in the system. Film rupture obviously occurs as a result of dynamic processes. Film drainage (thinning) rate is influenced by surface concentration gradients in the surfactant layers at film surfaces and by the effects of Marangoni flow within the films. To be stable, films need to have elastic properties in order to withstand mechanical perturbations. If the repulsive forces between surfaces become insufficient, hole formation will lead to film rupture.
APA, Harvard, Vancouver, ISO, and other styles
4

"* ** Fig. 39 Cyclone-type homogenizer mixing chamber. (From Ref. 41.) chamber. The symmetry axes of these entry ports are perpendicular to the symmetry axis of the interaction chamber. This design is presented in Fig. 40, with only four entry ports. This machine is called Novamix® (a registered name for Micro Vesicular Sys-tems). It was originally designed to process and produce nonphospholipid lamellar mi-crostructures or lipid vesicles. The lipid vesicles are composed of two immiscible aqueous and lipid phases. The lipid phase consists, generally, of solid polyoxyethylene-derived amphiphiles that form micelles in aqueous media. Under the proper mixing conditions, i.e., a combination of shear, heat, and turbulence, followed by appropriate cooling, the micelles of these types of lipids fuse to form lipid vesicles. The two phases are metered carefully and heated in separate reservoirs and finally pumped to the interaction chamber for pro-cessing. The interaction chamber and pump heads are confined in an insulated com-partment that is maintained at the required temperature for the production of the lipid vesicles. The outlet is attached to a chilling device that cools the product at the required rate [43]. The flow pattern is similar to that of a cyclone, i.e., the flow of liquid is in a vertically positioned rotating cylinder along its vertical axis. The streamlines are con-centric circles with their radii decreasing toward the center of the cylinder. The de-crease is a function of cylinder radius, flow rate of fluid (speed of rotation), and other parameters like viscosity, density, and surface tension of the formulation. In curved type of flow with changing radii, there exists a pressure gradient, i.e. dPIdr = V /r (8) where P = pressure; r = vessel (interaction chamber) radius; V = tangential linear velocity; and p= the liquid density. Since the change in pressure is positive for a positive radius change, the pressure at successive points increases from the concave to the convex side of the streamline [39]. The exact change in pressure depends on the variation in tangential linear velocity, which is proportional to the speed of the rotation and the ra-dius. The flow pattern in the interaction chamber is neither a free vortex, due to the presence of an initial momentum from the pumps, nor a forced vortex, for the stream-." In Pharmaceutical Dosage Forms, 368–69. CRC Press, 1998. http://dx.doi.org/10.1201/9781420000955-55.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Liquid entry pressure"

1

Martin, C. Samuel. "Condensation-Induced Water Hammer in Horizontal Refrigerant Pipe With Warm Gas Entry." In ASME/JSME 2003 4th Joint Fluids Summer Engineering Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/fedsm2003-45678.

Full text
Abstract:
Careful experiments have been conducted for the purpose of investigating the phenomenon of condensation-induced waterhammer in an ammonia refrigeration system. To initiate a waterhammer event warm ammonia gas was introduced over static subcooled ammonia liquid placed in a horizontal 146.3 mm diameter carbon steel pipe 6.0 m in length. By means of fast response piezoelectric pressure transducers and a high speed data acquisition system rapid dynamic pressures were recorded whenever a shock event occurred. The occurrence of condensation-induced waterhammer depended upon three major variables; namely, (1) initial liquid depth, (2) liquid temperature, and (3) mass flow rate of warm gas. For given liquid depth and temperature, once the warm gas threshold conditions were exceeded shocks occurred with greater magnitude as the mass flow rate of gas input was increased. With adequate subcooling condensation-induced waterhammer occurred for initial liquid depths ranging from 25% to 95% of internal pipe diameter. The threshold mass flow rate of warm gas necessary to initiate waterhammer was greater as the initial liquid was lowered.
APA, Harvard, Vancouver, ISO, and other styles
2

La Foy, Roderick R., Sunghwan Jung, and Pavlos Vlachos. "Long Term Dynamics of Water-Entry Cavity." In ASME 2010 3rd Joint US-European Fluids Engineering Summer Meeting collocated with 8th International Conference on Nanochannels, Microchannels, and Minichannels. ASMEDC, 2010. http://dx.doi.org/10.1115/fedsm-icnmm2010-31210.

Full text
Abstract:
Many engineering applications involve the motion of objects crossing a fluid interface. The dynamics of this process are often complicated due to the interplay of surface tension, gravity, and inertia. Nevertheless, a simple analysis using potential flow theory works well to predict the interfacial profile of the air cavity formed during an impact. Most current theories however, cannot predict the behavior of the air cavity after pinch off occurs. We therefore investigated the long term dynamics of water entry in both experiment and theory. It was found that shortly after pinch off the cavity dynamics become governed primarily by thermodynamic gas relations. The internal pressure slowly rises due to the cavity volume decreasing while the ambient liquid pressure quickly increases as a result of the descent of the projectile. This effect is incorporated into our model to correctly predict the cavity geometry.
APA, Harvard, Vancouver, ISO, and other styles
3

Guzel, Bulent, and Fatih C. Korkmaz. "Experimental Investigation of Water Entry Impact on Hydrophobic Surfaces." In ASME 2015 34th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/omae2015-41729.

Full text
Abstract:
The results of an experimental investigation on hull bottom slamming of three different geometries, sphere, cylinder and wedge, with hydrophobic surfaces are presented. In water entry of blunt bodies, different fluid dynamics phenomena like jet formation, cavity formation, water splashing, flow separation on solid surfaces and air entrapment between solid and liquid surface have been studied for decades. Our study is aimed at understanding and modeling the dynamics of slamming under an extended range of parameters including hydrophobic surfaces. In this study, drop tests have been set up for hull bottom slamming by dropping a body from various heights toward water surface. From digital images captured using a high speed camera, flow separation and water splashing at different velocities are observed and spreading diameters and entrance characteristics are measured during the impact process. At the same time, we measure the pressure distribution on the surface of the bodies during impact via strain gages.
APA, Harvard, Vancouver, ISO, and other styles
4

Gillespie, D. R. H., S. M. Guo, Z. Wang, P. T. Ireland, and S. T. Kohler. "A Comparison of Full Surface Local Heat Transfer Coefficient and Flow Field Studies Beneath Sharp-Edged and Radiused Entry Impinging Jets." In ASME 1996 International Gas Turbine and Aeroengine Congress and Exhibition. American Society of Mechanical Engineers, 1996. http://dx.doi.org/10.1115/96-gt-428.

Full text
Abstract:
Full heat transfer coefficient and static pressure distributions have been measured on the target surface under impinging jets formed by sharp-edged and large entry radius holes. These geometries are representative of impingement holes in a gas turbine blade manufactured by laser cutting and by casting, respectively. Target surface heat transfer has been measured in a large scale perspex rig using both the transient liquid crystal technique and hot thin film gauges. A range of jet Reynolds numbers, representative of engine conditions, has been investigated. The velocity variation has been calculated from static pressure measurements on the impingement target surface. The heat transfer to the target surface is discussed in terms of the interpreted flow field.
APA, Harvard, Vancouver, ISO, and other styles
5

Dolatabadi, Amirali, Drazen Fabris, and Dean Samara-Rubio. "Isothermal Efficiency of Liquid Piston Compressors Employed in Compressed Air Energy Storage Systems." In ASME 2013 Fluids Engineering Division Summer Meeting. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/fedsm2013-16510.

Full text
Abstract:
This paper models the compressor work for a prototype small-scale compressed air energy storage system to predict the heat transfer to the walls and the system pressure, temperature, and work required. The modeled system uses a hydraulically driven compressor to enable variable frequencies of compression and to improve heat transfer. Since the compression is hydraulically driven, speed of compression can be controlled through adjusting hydraulic pump’s speed in order to enhance the efficiency and also being able to couple the system with different sources of power. The energy conservation model considers gas under non-ideal conditions and properties of the gas are predicted using Redlich-Kwong equation of state. For heat transfer calculations, correlations for thermal entry length for turbulent flows are employed. Material properties of air including specific heat capacity, thermal conductivity and viscosity are corrected at different operating temperatures and pressures. The differential equation form of the first law of thermodynamics is then integrated numerically in the time domain in order to find the instantaneous properties of the bulk gas. Isothermal efficiency is then predicted based on the temperature rise in the working fluid during compression. It is determined that at low frequencies of compression, at a compression ratio of 5:1, isothermal efficiencies as high as 93% can be achieved.
APA, Harvard, Vancouver, ISO, and other styles
6

Hwang, J. J., C. S. Cheng, and Y. P. Tsia. "Heat Transfer Enhancement in Triangular Ducts With an Array of Side-Entry Wall/Impinged Jets." In ASME 1999 International Gas Turbine and Aeroengine Congress and Exhibition. American Society of Mechanical Engineers, 1999. http://dx.doi.org/10.1115/99-gt-195.

Full text
Abstract:
An experimental study has been performed to measure local heat transfer coefficients and static well pressure drops in leading-edge triangular ducts cooled by wall/impinged jets. Coolant provided by an array of equally spaced wall jets is aimed at the leading-edge apex and exits from the radial outlet. Detailed heat transfer coefficients are measured for the two walls forming the apex using transient liquid crystal technique. Secondary-flow structures are visualized to realize the mechanism of heat transfer enhancement by wall/impinged jets. Three right-triangular ducts of the same altitude and different apex angles of β = 30 deg (Duct A), 45 deg (Duct B) and 60 deg (Duct C) are tested for various jet Reynolds numbers (3000≦Rej≦12600) and jet spacings (s/d = 3.0 and 6.0). Results show that an increase in Rej increases the heat transfer on both walls. Local heat transfer on both walls gradually decreases downstream due to the crossflow effect. At the same Rej, the Duct C has the highest wall-averaged heat transfer because of the highest jet center velocity as well as the smallest jet inclined angle. Moreover, the distribution of static pressure drop based on the local through flow rate in the present triangular duct is similar to that that of developing straight pipe flows. Average jet Nusselt numbers on the both walls have been correlated with jet Reynolds number for three different duct shapes.
APA, Harvard, Vancouver, ISO, and other styles
7

Brewer, Melanie, Derek Andel, and Parag Bandyopadhyay. "Production Optimization Using CO2 Gas Lift in EOR Fields: A Permian Basin Case Study." In SPE Artificial Lift Conference and Exhibition - Americas. SPE, 2022. http://dx.doi.org/10.2118/209728-ms.

Full text
Abstract:
Abstract Carbon dioxide (CO2) is commonly used for enhanced oil recovery (EOR) in the Permian Basin and is gaining interest for Carbon Capture, Utilization & Storage. A study was conducted to develop candidate selection criteria, pilot test the design, and optimize CO2 gas lift to stabilize production on intermittently flowing wells in one of these EOR fields. The initial CO2 gas lift design was installed in 2019 using a capillary string, downhole check valve, gas lift mandrel, and packer. A 34-day bottomhole pressure and temperature survey was evaluated to assess the success of the pilot and improve the equipment design for future installations. The phase changes of CO2 were accounted for when evaluating the pilot, modeling gas lift, and improving equipment design. Carbon dioxide is a complex fluid at the bottomhole pressures (BHP) and temperatures (BHT) observed during the pilot. These pressures and temperatures were plotted on the CO2 phase diagram, which showed phase changes between vapor and liquid at higher gas lift injection rates. Further analysis revealed the CO2 changed phase from a liquid to a vapor across the downhole check valve. The Joule-Thompson (JT) effect across the check valve at the tubing entry point dropped the temperature of the produced fluids so much that the CO2 changed phase from a vapor back to a liquid. This increased the hydrostatic pressure and therefore, the bottomhole flowing pressure. These CO2 phase changes in the tubing occurred in cycles comprising five distinct stages: (1) BHT cooling forced CO2 from the vapor to liquid phase and increased BHP; (2) BHT remained fairly steady as BHP increased due to liquid loading; (3) BHT started warming at a faster rate as BHP rose due to the decreasing pressure drop across the downhole check valve; (4) the tubing unloaded as CO2 flashed in a chain reaction down the tubing, resulting in an influx of warmer reservoir fluid; and (5) BHT remained steady as BHP decreased and the annular packer fluid restarted the cooling process. Results from this initial pilot were used successfully to optimize CO2 gas lift for subsequent installations. CO2 gas lift can be an effective artificial lift method to stabilize production if the equipment is designed correctly to maximize the CO2 gas fraction at the tubing entry point. A poorly designed CO2 gas lift installation may result in unstable production from liquid loading events caused by the cyclic JT effect. CO2 gas lift is a valuable artificial lift method to reduce failure frequency and operating costs in EOR fields with readily available CO2.
APA, Harvard, Vancouver, ISO, and other styles
8

Liu, Cun-liang, Hui-ren Zhu, Jiang-tao Bai, and Du-chun Xu. "Film Cooling Performance of Converging-Slot Holes With Different Exit-Entry Area Ratios." In ASME Turbo Expo 2009: Power for Land, Sea, and Air. ASMEDC, 2009. http://dx.doi.org/10.1115/gt2009-59002.

Full text
Abstract:
Film cooling performances of two kinds of converging slot-hole (console) with different exit-entry area ratios have been measured using a new transient liquid crystal measurement technique which can process the nonuniform initial wall temperature. Four momentum ratios are tested. The film cooling effectiveness distribution features are similar for the two consoles under all the momentum ratios. Consoles with smaller exit-entry area ratio produce higher cooling effectiveness. And the laterally averaged cooling effectiveness results show that the best momentum ratio for both consoles’ film cooling effectiveness distribution is around 2. For both consoles, the heat transfer in the midspan region is stronger than that in the hole centerline region in the upstream, but gradually becomes weaker as flowing downstream. With the momentum ratio increasing, the normalized heat transfer coefficient h/ho of both consoles increases. In the upstream, heat transfer coefficient of console with small exit-entry area ratio is higher. But in the downstream, the jets’ turbulence and the couple vortices play notable elevating effect on the heat transfer coefficient for large exit-entry area ratio case, especially under small momentum ratios. Consoles with smaller exit-entry area ratio provide better thermal protection because of higher cooling effectiveness. And the distributions of heat flux ratio are similar with those of cooling effectiveness because the influence of η on q/q0 is larger. For the consoles, smaller exit-entry area ratios produce lower discharge coefficients when the pressure variation caused by the hole shaped is regarded as flow resistant.
APA, Harvard, Vancouver, ISO, and other styles
9

Aditya, K. P., and T. M. Muruganandam. "Detection of Precursor Event Before Blowout in a Gas Turbine Type Combustor at Atmospheric Pressure." In ASME 2012 Gas Turbine India Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/gtindia2012-9585.

Full text
Abstract:
The need for stringent emission requirements compel modern gas turbine (GT) combustors to work under lean conditions and lower temperatures, thereby reducing NOx emissions. The operation of a combustor close to lean blowout limit increases the risk of a complete flame blowout posing a safety hazard in aircraft engines. A study was carried out on a divergent gas turbine combustor, in order to sense and detect a similar blowout phenomenon in a non/partially premixed swirl flame. Inside combustor, 45° vane angle swirler created weak recirculation zone. New swirler with 5° and 60° at entry and exit respectively was used as replacement. 5 bar and 6 bar of stagnation pressure of air were used as loading parameters during the experimentation. Photodiode sensors and high speed imaging camera were used to record data of flame. It was observed that, bursts (or unsteady events) characterized by an almost complete loss of flame i. e. abrupt extinctions were followed by re-occurrence of flame. ‘Precursor events’ before flame blowout were detected. These events occurred and reoccurred in an interval of several milliseconds. In both scenarios, high speed visualization was recorded at 1000 Hz for 16–20 seconds. Detection of precursor events for the liquid fuelled combustor will assist in carrying out further research using sensing methods to estimate the proximity of the combustor to LBO.
APA, Harvard, Vancouver, ISO, and other styles
10

Price, Donald C., W. Gerald Wyatt, Pete Townsend, Mark C. Woods, and Brad W. Fennell. "Design of a Transient, Temperature Control System for a Low-Temperature Infrared Optical Telescope Utilizing a Ramai R-Cooled Thermoelectric Assembly as the Condenser of a Two-Phase Cooling System." In ASME 2005 Pacific Rim Technical Conference and Exhibition on Integration and Packaging of MEMS, NEMS, and Electronic Systems collocated with the ASME 2005 Heat Transfer Summer Conference. ASMEDC, 2005. http://dx.doi.org/10.1115/ipack2005-73496.

Full text
Abstract:
The design of a thermal management system for an airborne, infrared, optical telescope system is described. This system provides transient thermal management for the optical elements of the system beginning at a high-temperature soak condition of 71°C (159.8°F) on the ground to a low-temperature operating condition of −30°C (−22°F) to −40°C (−40° F) within 45 min after aircraft takeoff. An active cooling system is employed to enable this rapid cooldown. In addition to the low-temperature requirement, the mirrors and lenses must be cooled so that temperature gradients across the optical elements are on the order of 1°C (33.8 °F) to 2°C (35.6 °F). The ambient air available for ground cooling is specified by the military environment to be 55°C (131.0 °F). As the aircraft takes off and climbs to an altitude of 11,582.4 m (38 kft), the ambient air temperature decreases to a low-temperature of −22°C (−7.6 °F) for steady, level flight at at Mach 0.9, this ambient air temperature results in a ram air inlet temperature on the order of 13.5°C (56.3 °F), after the air is captured and diffused to Mach 0.2 prior to entry into a ram air heat exchanger. This ram air heat sink is used to provide a chilled liquid for cooling of optical elements and the turret housing the system. The low temperatures required for this system, which are on the order of −30°C (−22 °F) to −40°C (−40 °F), make the use of forced-convection, liquid-cooling problematic because of the tendancy of liquids to become quite viscous as they approach these low temperature levels. Furthermore, the use of a single-phase heat transfer process will result in temperature gradients within the system. For these reasons, cooling concepts employing single-phase cooling using chilled-liquids have been eliminated from consideration. A low-temperature, low-pressure refrigerant, R-404a, is used as the working fluid. The themal management system uses the optical elements as the evaporator of a two-phase cooling system. The liquid refrigerant is introduced into the optical elements at the saturation temperature and saturation pressure of the liquid. The flow rate of the refrigerant will be controlled in such a manner that all of the heat transfer takes place in the liquid-vapor mixture region of the thermodynamic diagram for R-404a with the refrigerant exiting the elements at an arbitraily determned quality of approximately 0.8. This will assure that all of the heat transfer will be by boiling heat transfer and will take place at a constant temperature and essentially a constant pressure. Since the heat transfer coefficients are large and the process takes place at essentially a constant temperature, the optical elements will be controlled at the saturation temperature of the refrigerant and will be essentially a constant temperature across the expanse of the optical surface. The thermal management system is comprised of an array of TECs configured as a condenser HX. This TEC HX uses ram air as the eventual heat sink and will provide chilled-liquid produced by a liquid-to-ram air HX as the heat sink for the hot side of the TEC array. This system utilizes the system mass as the evaporator and a TEC HX as the condenser in a two-phase heat transfer process to provide rapid cooldown of the system mass to low temperatures in a short period of time and maintain that mass at proper operating temperatures with essentially zero temperature gradients throughout the system.
APA, Harvard, Vancouver, ISO, and other styles
You might also be interested in the extended bibliographies on the topic 'Liquid entry pressure' for particular source types:
Journal articles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography