Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 62 for “"annular flow"”.
-
Dryout limits in horizontal annular flow
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1992.
-
Annular Flow in a Low - Pressure Steam - Water System
<p>Two-phase annular flow is an important aspect of two- phase flow. Three different models, Ghosal, Wallis, and Levy models, were used to calculate the pressure drop in an nular two-phase flow. The calculated pressure drop was com pared with a set of experimental data. The pressure range of the …
-
Annular Flow Synthesis and Assembly of Two-Dimensional Materials
… micromixing tests. By operating in the two-phase annular flow regime, it is possible to form microfilms with tuneable shear rates as high as ~1E6 s-1 and sub-millisecond micromixing. By synthesizing layered double hydroxides in this reactor over different shear rates, I found that crystallinity …
-
Advancement of closure relations for annular flow modeling in CFD
… ability to model the complex three-dimensional flow structures in annular flow regime [1], while physics-based constitutive equations are needed to accurately represent the phase interactions, particularly at the liquid film interface. The development of closure relations for droplet deposition …
-
Analytical modelling of annular flow magnetorheological valves for advanced fluid control
… to reduce the timeline of development for annular ow magnetorheological valves. The model was validated to simulation and experimental results and an application of the model was demonstrated in the design of an magnetorheological valve. This proposed model will facilitate thorough …
-
Mist to annular flow development quantified by novel video analysis methods
… measurements of the film and droplets found in annular-mist flows to be extracted from a single video. This method allows measurements to be made without altering the internal geometry or flow path. Flow parameters such as drop size, velocity, and concentration and film wavelength and wave speed …
-
Measurement of Liquid Film in Annular Flow Using X-Ray Densitometry
Two-phase annular flow film thickness is a crucial parameter in nuclear thermal hydraulics, yet conventional measurement techniques such as impedance probes may compromise accuracy by directly contacting and potentially disturbing the flow. Non-intrusive measurement methods are needed to provide …
-
Modeling of the Evaporation and Condensation of Zeotropic Refrigerant Mixtures in Horizontal Annular Flow
The model demonstrates the mechanisms which cause circumferential and axial composition and temperature gradients in the liquid film when zeotropic mixtures undergo evaporation and condensation. Heat transfer in mixtures is shown to be less than the ideal limit due to mass transfer resistance in …
-
Simulation of liquid entrainment in BWR annular flow using an interface tracking method approach
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Nuclear Science and Engineering, 2012.
-
An Experimental Study of Subcooled Flow Boiling at Elevated Pressure in an Annular Flow Channel
… was developed to study the region of subcooled flow boiling. Multiple studies were carried out to investigate the effects of liquid velocity, pressure, and temperature on the boiling heat transfer of subcooled fluid flowing through a heated annular channel. Water was used as the working fluid …
-
Atomization and Deposition in Two-Phase Annular Flow: Measurement and Modeling (Pressure Drop, Thin Films, Turbulent Dispersion)
… of atomization from the wall layer in vertical annular two-phase flow and of deposition of this liquid back to the liquid film. These models have been incorporated into a design scheme for the prediction of two-phase pressure drop and fully developed entrained liquid fraction for the annular …
-
Thermohydraulics and suppression of nucleate boiling in upward two-phase annular flow : probing multiscale physics by innovative diagnostics
… qualities (typical of the bubbly and slug/churn flow regimes), while forced convective evaporation dominates at higher steam quality in the annular flow regime. The transition of the heat transfer mechanism, also called suppression of nucleate boiling (SNB), affects the local heat transfer …
-
Use of Lagrangian methods to describe particle deposition and distribution in dispersed flows
… the interchange processes in vertical gas-liquid annular flow by Leman (1985) and Schadel (1988) in this laboratory have been completed. This work defines the effect of pipe diameter, gas and liquid flow rates on deposition rates in air-water annular flow. An estimate of the droplet slip ratios …
-
Enhancing the injectability of high concentration drugs via core annular flows
… enhance formulation injectability through a core annular flow that lubricates viscous transport through a needle. We study the importance of different flow regimes and density based eccentricity in dictating lubrication in the needle. Finally, we quantify the maximum pressure reduction that can be …
-
Development, Evaluation and Improvement of Correlations for Interphase Friction in Gas-Liquid Vertical Upflow
In this study, liquid-vapor vertical upflow has been research with the intent of finding an improved method of modelling the interphase friction in two-phase vertical flow in nuclear thermal-hydraulic codes. An improved method of modelling interphase friction should allow for better prediction of …
-
STUDY OF AIR BUBBLE INJECTION INTO LAMINAR AND TURBULENT WATER FLOW THROUGH AN ANNULAR TEST SECTION
Injection of bubbles into a vertical upward flow of water in an annular flow channel was studied experimentally under laminar and turbulent conditions. In order to measure the size and shape of the bubbles, a flow visualization system was set up in a vertical test section with a high speed video …
-
Infrared Thermometry Analysis of Surface Effects in Subcooled and Saturated Boiling of Water
… work, the dynamics of subcooled and saturated flow boiling are studied, focusing on the influence of surface characteristics, visualized through advanced diagnostics capturing micro-scale phenomena. Utilizing specially crafted thin-film infrared heaters, we measured bubble dynamics parameters …
Page 1 of 4