Modelling and simulation of the dynamic flow behaviour in a bubble column

Gas—liquid flow in bubble columns and loop reactors: Part II. Comparison of detailed experiments and flow simulations

Flow turbulence generated by a bubble plume in a large tank is characterized. Two different turbulence mechanisms contributing to the mixing and transport process are identified on velocity signals recorded outside of the bubble-plume core: a macro-scale process governed by the wandering motion of the bubble-plume; and an intermediate- and micro-scale process represented by the Kolmogorov power spectrum. A methodology is presented to characterize the different processes and their contributions to the turbulence parameters. The results help to understand the bubble-plume phenomenon and provide a basis to validate numerical models of bubble-plumes used in the design of combined-sewer-overflow reservoirs.

Characterization of flow turbulence in large-scale bubble-plume experiments

An important topic in fluid dynamics is multiphase flows. Multiphase flows can be found in numerous fields in engineering, e.g. aerospace, biomedical, chemical, electrical, environmental, mechanical, materials, nuclear and naval engineering. There is an enormous variation in applications, e.g. rocket engines, chemical reactors, contamination spreading, multiphase mixture transport, cavitation, sonoluminescence, ink-jet printing, particle transport in blood, crystallization, multiphase cooling, fluidized beds, drying of gases, air entrainment in oceans/rivers and anti-icing fluids. The number of papers on multiphase flow in the field of fluid dynamics is enormous and still growing. The diversity of flow types makes a general description almost impossible. This makes fundamental research necessary. Especially, controlled experiments are needed for a better physical understanding and as test cases for numerical and theoretical work. The purpose of this paper is the desire to demonstrate, review and summarize the major finding of the previous research of bubbly two-phase flow characteristics, structures, behaviors and flow patterns. Moreover, to elucidate some important models and techniques to measure the two-phase bubbly flow parameters such as bubble motion, flow regime, bubble shape which play a considerable role in many engineering applications.

/pdf/bubbly-two-phase-flow-part-i-characteristics-structures-4z11lp9kej.pdf

Bubbly Two-Phase Flow: Part I- Characteristics, Structures, Behaviors and Flow Patterns

Computer-automated radioactive particle tracking (CARPT) data obtained in a 0.162 m air-water bubble column operated at ambient pressure have been analysed. The superficial gas velocity (U g ) has been varied in the range 0.02-0.12 m/s under constant liquid height 1.04 m. A perforated plate (82 holes O 0.4 mm, free plate area 0.05%) distributor has been used. The Kolmogorov entropy (KE) vs. U g allows identification of the transition velocity (U trans =0.064 m/s) between bubbly and transition regimes. KE models for both regimes have been also developed. The quality of mixedness (QM) concept shows that QM(upper zone).QM(lower zone) at U trans = 0.064 m/s.

Flow Regime Identification in a Bubble Column Based on both Kolmogorov Entropy and Quality of Mixedness Derived from CAERPT Data

Local gas holdups and bubble size distributions have been measured simultaneously in a standard-type bubble column equipped with a perforated plate as a gas disperser. High values in the time series of the local gas holdup which appear on a periodic basis could be detected and analyzed. The phenomenon of the bubble hose, defined as a zone of high bubble number density moving helically in a bubble column, has been recognized visually using photographs and by means of the recorded data. A formation mechanism for the bubble hose dependent on the gas disperser geometry capable of explaining the observed asymmetric liquid and gas flow pattern is suggested. The existence of a relationship between the bubble hose, the average bubble diameter and the superficial gas velocity has been demonstrated.

On the local gas holdup and flow pattern in standard-type bubble columns

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

E. Sada

Author Tools

Chat about Author

Papers

On the local gas holdup and flow pattern in standard-type bubble columns