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 21 for “"subcooled flow boiling"”.
-
An Investigatio of Subcooled flow Boiling with Emphasis o nits Initiation
Made available in DSpace on 2017-07-06T18:55:40Z (GMT). No. of bitstreams: 2 Nourmohammadi_Khosrow_MS.pdf: 44965532 bytes, checksum: e061f1448c007bf887afc3534ab2da4a (MD5) license.txt: 4813 bytes, checksum: 715c4321821a960fa1a1e91d2ac7ebce (MD5) Previous issue date: 1980
-
Bubble behavior in subcooled flow boiling on surfaces of variable wettability
Flow boiling is important in energy conversion and thermal management due to its potential for very high heat fluxes. By improving understanding of the conditions leading to bubble departure, surfaces can be designed that increase heat transfer coefficients in flow boiling. Bubbles were visualized …
-
Experimental study of heat flux partitioning in pressurized subcooled flow boiling
Understanding of subcooled flow boiling and the critical heat flux (CHF) is of the utmost importance for both safety and profitability of pressurized water nuclear reactors since they are major factors in the determination of the reactor power rating. Motivated by the emergence of a new wall …
-
Synthesis of CRUD and its effects on pool and subcooled flow boiling
… (Chalk River Unidentified Deposits) on pool and subcooled flow boiling parameters. Previous pool boiling studies have demonstrated the potential of porous, hydrophilic surfaces to lead to more efficient boiling. CRUD is a naturally occurring porous, hydrophilic layer that forms on fuel rods …
-
Experimental study on subcooled flow boiling on heating surfaces with different thermal conductivities
Subcooled flow boiling is generally characterized by high heat transfer capacity and low wall superheat, which is essential for cooling applications requiring high heat transfer rate, such as nuclear reactors and fossil boilers. In this study, subcooled flow boiling on copper and stainless steel …
-
Investigation of Separate Effects of Surface Condition on Subcooled Flow Boiling Heat Transfer
… effectively transferred to the water coolant by subcooled flow boiling. The maximum reactor power is limited by the critical heat flux (CHF), at which the boiling crisis occurs. Understanding the mechanisms that trigger this boiling crisis and predicting the CHF limit is key to the safety and …
-
An Experimental Study of Subcooled Flow Boiling at Elevated Pressure in an Annular Flow Channel
… setup 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 …
-
Experimental Investigation of Subcooled Flow Boiling and CHF at Prototypical Pressures of Light Water Reactors
Boiling crisis is an important phenomenon that affects the performance and safety of pressurized water reactors (PWRs). Accurate predictions of the boiling crisis are difficult to make because they require a clear understanding of the physical mechanisms leading to the boiling crisis combined with …
-
Subcooled flow boiling heat transfer and critical heat flux in water-based nanofluids at low pressure
… in water, or other base fluids. Previous pool boiling studies have shown that nanofluids can improve the critical heat flux (CHF) by as much as 200%. In this study, subcooled flow boiling heat transfer and CHF experiments were performed with low concentrations of alumina, zinc oxide, and …
-
Development and assessment of a physics-based model for subcooled flow boiling with application to CFD
Boiling is an extremely efficient mode of heat transfer and is the preferred heat removal mechanism in power systems in general and, more recently, in electronics cooling. Physics-based models that describe boiling heat transfer, when coupled with Computational Fluid Dynamics (CFD), can be an …
-
Experimental investigation of subcooled flow boiling using synchronized high speed video, infrared thermography, and particle image velocimetry
Subcooled flow boiling of water was experimentally investigated using high-speed video (HSV), infrared (IR) thermography, and particle image velocimetry (PIV) to generate a unique database of synchronized data. HSV allowed measurement of the bubble departure diameter. IR thermography allowed …
-
The effects of orientation angle, subcooling, heat flux, mass flux, and pressure on bubble growth and detachment in subcooled flow boiling
… and pressure on bubble growth and detachment in subcooled flow boiling were studied using a high-speed video camera in conjunction with a two-phase flow loop that can accommodate a wide range of flow conditions. Specifically, orientation angles of 0' (downward-facing horizontal), 30°, 45°, 60°, …
-
Water evaporation in vertical tubes: an analytical approach for the subcooled flow boiling region and development of a method for evaluation and sizing evaporators = Evaporación de agua en tubos verticales: análisis de la región de ebullición subenfriada y desarrollo de un método de evaluación y Dimensionado de evaporadores
… of water evaporation for convective upward flows in vertical tubes, used in industrial applications. Both, the heat transfer process and the pressure drop mechanism, are considered. However, special attention has been put on the heat transfer process in the transition from pure liquid to …
-
Infrared Thermometry Analysis of Surface Effects in Subcooled and Saturated Boiling of Water
In this 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 …
-
Advancing State-of-the-art Multiphase CFD Modeling for PWR Applications
… to provide high fidelity simulation of complex boiling phenomena in Light Water Reactors (LWRs), thereby accelerating the development cycle and reducing the need for expensive large-scale experiments. M-CFD relies on two-phase closure models to consistently represent the relevant physical …
-
Development of a general purpose subgrid wall boiling model from improved physical understanding for use in computational fluid dynamics
… capabilities were developed for application to subcooled flow boiling through this work. The target was to introduce, and demonstrate, all necessary mechanisms required to accurately predict the temperature and heat flux for subcooled flow boiling in CFD simulations. The model was developed …
-
Geometric and numerical optimisation of single- and two-phase convective heat transfer in microchannel heat sinks
… square microchannels (micro passages for liquid flow in the heat sinks) were studied to enable electronic chip manufacturers to produce more powerful and durable integrated circuits at temperatures well below the recommended highest operating temperature. There is the need to optimise different …
-
Experimental Investigation of Critical Heat Flux Enhancement on Engineered Surfaces with Infrared Thermometry
The boiling crisis is one of the most intriguing and impactful open problems in thermal science and engineering. The prediction and enhancement of the heat flux at which this boiling crisis occurs (also known as critical heat flux, or CHF) has been the focus of boiling heat transfer research for …
-
Modeling and simulation of liquid microlayer formation and evaporation in nucleate boiling using computational fluid dynamics
The transport of latent heat makes boiling one of the most efficient modes of heat transfer, allowing a wide range of systems to improve their thermal performance, from microelectronic devices to nuclear power plants. In particular, Boiling Water Reactors (BWR) use boiling as the primary mode of …
-
Experiments on two-phase heat transfer regimes in vertical downward flow: From nucleate to film boiling
Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2025-03-28 without embargo terms
Page 1 of 2