A statistical analysis of EHD-enhanced nucleate boiling along a heated wire

Bubbles have been observed moving along heated wires during subcooled nucleate boiling as they are driven by Marangoni convection around the bubbles. This paper presents more detailed observations of the vapor bubble interactions and moving bubble behavior during subcooled nucleate boiling on a heated microwire. The experimental results show that moving bubbles coalesce or rebound from other bubbles and that bubbles hop on the wire. These observations show how bubble interactions significantly affect nucleate boiling heat transfer rates and how Marangoni flow plays an important role in microscale nucleate boiling heat transfer mechanisms.

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Statistical analysis of the sensitivity of bubble sample size during saturated nucleate boiling based on experimental data

International Journal of Heat and Mass Transfer ◽

10.1016/j.ijheatmasstransfer.2018.10.012 ◽

2019 ◽

Vol 129 ◽

pp. 1295-1304 ◽

Cited By ~ 1

Author(s):

Yuan Yao ◽

Quan Zhong ◽

Gao-Fei Chen ◽

Han-Zhi Chen ◽

Mao-Qiong Gong

Keyword(s):

Experimental Data ◽

Statistical Analysis ◽

Sample Size ◽

Nucleate Boiling

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Forced vibration of a heated wire subjected to nucleate boiling

International Journal of Heat and Mass Transfer ◽

10.1016/j.ijheatmasstransfer.2019.01.101 ◽

2019 ◽

Vol 135 ◽

pp. 44-51 ◽

Cited By ~ 5

Author(s):

Christopher Staszel ◽

Suman Sinha-Ray ◽

Alexander L. Yarin

Keyword(s):

Forced Vibration ◽

Nucleate Boiling ◽

Heated Wire

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Experimental and Numerical Investigation of the Dynamics of Moving Vapor Bubbles

Heat Transfer: Volume 2 ◽

10.1115/ht2005-72415 ◽

2005 ◽

Author(s):

David M. Christopher ◽

Hao Wang ◽

Xiaofeng Peng

Keyword(s):

Nucleate Boiling ◽

Jet Flows ◽

Marangoni Flow ◽

Bubble Motion ◽

Vapor Bubbles ◽

Physical Mechanisms ◽

Noncondensable Gases ◽

Temperature Distributions ◽

Heated Wire ◽

Surface Temperature Gradient

Jet flows have been observed flowing from the tops of vapor bubbles during nucleate boiling in a variety of situations. This paper analyzes the physical mechanisms that cause jet flows to emanate from the tops of bubbles moving along microwires. The flows were analyzed by numerically solving the governing differential equations for the 3-D velocity and temperature distributions around the bubble and the heated wire as the bubble moves along the wire. The results show that the flow is most likely driven by the temperature difference from the front to the back of the bubble resulting from the bubble motion which would cause Marangoni flow. The Marangoni flow provides thrust to push the bubble forward. Comparisons with experimental observations suggests that the condensation heat transfer at the bubble interface must be restricted by noncondensable gases would increase the surface temperature gradient which would in turn increase the resulting Marangoni flow.

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Statistical analysis of classification

Symposium - International Astronomical Union ◽

10.1017/s0074180900053420 ◽

1966 ◽

Vol 24 ◽

pp. 188-189

Author(s):

T. J. Deeming

Keyword(s):

Multivariate Analysis ◽

Statistical Analysis ◽

Classification Scheme ◽

Analytical Procedure ◽

Narrow Band ◽

Scientific Research ◽

Maximum Amount ◽

Amount Of Information

If we make a set of measurements, such as narrow-band or multicolour photo-electric measurements, which are designed to improve a scheme of classification, and in particular if they are designed to extend the number of dimensions of classification, i.e. the number of classification parameters, then some important problems of analytical procedure arise. First, it is important not to reproduce the errors of the classification scheme which we are trying to improve. Second, when trying to extend the number of dimensions of classification we have little or nothing with which to test the validity of the new parameters.Problems similar to these have occurred in other areas of scientific research (notably psychology and education) and the branch of Statistics called Multivariate Analysis has been developed to deal with them. The techniques of this subject are largely unknown to astronomers, but, if carefully applied, they should at the very least ensure that the astronomer gets the maximum amount of information out of his data and does not waste his time looking for information which is not there. More optimistically, these techniques are potentially capable of indicating the number of classification parameters necessary and giving specific formulas for computing them, as well as pinpointing those particular measurements which are most crucial for determining the classification parameters.

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Quantitative parallel EELS spectrum imaging developed as a new tool in AEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010013064x ◽

1992 ◽

Vol 50 (2) ◽

pp. 1202-1203

Author(s):

Gianluigi Botton ◽

Gilles L'espérance

Keyword(s):

Statistical Analysis ◽

Spatial Resolution ◽

Personal Computer ◽

Systematic Study ◽

Present Author ◽

Chemical Elements ◽

Detection Limits ◽

Research Groups ◽

Quantitative Performance ◽

Spectrum Imaging

As interest for parallel EELS spectrum imaging grows in laboratories equipped with commercial spectrometers, different approaches were used in recent years by a few research groups in the development of the technique of spectrum imaging as reported in the literature. Either by controlling, with a personal computer both the microsope and the spectrometer or using more powerful workstations interfaced to conventional multichannel analysers with commercially available programs to control the microscope and the spectrometer, spectrum images can now be obtained. Work on the limits of the technique, in terms of the quantitative performance was reported, however, by the present author where a systematic study of artifacts detection limits, statistical errors as a function of desired spatial resolution and range of chemical elements to be studied in a map was carried out The aim of the present paper is to show an application of quantitative parallel EELS spectrum imaging where statistical analysis is performed at each pixel and interpretation is carried out using criteria established from the statistical analysis and variations in composition are analyzed with the help of information retreived from t/γ maps so that artifacts are avoided.

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