Droplet size prediction model based on the upper limit log-normal distribution function in venturi scrubber

SummaryThere have been, in the past, many fatigue tests carried out on a variety of materials and components. These all indicate a wide scattering in the lives (measured by the number of stress cycles to failure) endured by nominally identical components subjected to nominally identical forces before failure occurs. To interpet this scattering several equations have been suggested as representing the statistical distribution functions that fit the lives obtained for individual types of component. Of these functions the log normal distribution function has been perhaps the most widely used. For the central regions of the probability distribution, i.e. about the mean, the log normal distribution and several others represent experimental results very closely indeed, but engineers and designers of all kinds dare not design on the mean fatigue life. They are concerned with specifications that either exclude the possibility of failure or admit only a very small probability of failure. It is thus with the accuracy with which the “lower tail” of the probability distribution curve fits the experimental results that they are concerned.To assess the fit at this lower end for one type of component, a large number (about 1,000) of aluminium specimens have been tested and the corresponding lives plotted. The results are very interesting. They show clearly that the log normal distribution for this type of component and material is pessimistic for a probability of failure of less than 0·3. This result is felt by the authors to be of very great importance. It has further been shown that the use of the “one-sided censored distribution function”, used previously by one of the authors, gives a curve that will fit the lower results better than the complete log normal distribution would do.It is with the testing procedure adopted, the specimens used, the distribution functions considered and the conclusions obtained therefrom that this paper is concerned.

Download Full-text

Study on the life distribution of microdrills

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1243/0954405021519889 ◽

2002 ◽

Vol 216 (3) ◽

pp. 301-305 ◽

Cited By ~ 8

Author(s):

Z Yang ◽

Y Chen ◽

Y Yang

Keyword(s):

Distribution Function ◽

Normal Distribution ◽

Reliability Function ◽

Test Methods ◽

Life Distribution ◽

Machining Processes ◽

Experimental Conditions ◽

Distribution Parameters ◽

Log Normal ◽

Log Normal Distribution

In this paper, the life distribution of microdrills has been studied experimentally. The fit and test methods of the life distribution function of microdrills are described. Under the experimental conditions of the present work, it is concluded that the life of microdrills follows the log-normal distribution and the distribution parameters are different for various workpiece materials. The life distribution function and reliability function of microdrills from the present work provide a base for correct changing of drills in automatic machining processes.

Download Full-text

Model development for fragment-size distribution based on upper-limit log-normal distribution

Nuclear Engineering and Design ◽

10.1016/j.nucengdes.2019.04.029 ◽

2019 ◽

Vol 349 ◽

pp. 86-91 ◽

Cited By ~ 2

Author(s):

J. Kim ◽

H.C. NO

Keyword(s):

Normal Distribution ◽

Size Distribution ◽

Fragment Size ◽

Model Development ◽

Fragment Size Distribution ◽

Upper Limit ◽

Log Normal ◽

Log Normal Distribution

Download Full-text

Peculiarities of data processing for optical measurements of disperse parameters of bimodal media

Computer Optics ◽

10.18287/2412-6179-2019-43-4-692-698 ◽

2019 ◽

Vol 43 (4) ◽

pp. 692-698 ◽

Cited By ~ 1

Author(s):

A.A. Zhirnov ◽

O.B. Kudrjashova

Keyword(s):

Experimental Data ◽

Particle Size ◽

Distribution Function ◽

Particulate Matter ◽

Particle Size Distribution ◽

Normal Distribution ◽

Size Distribution ◽

A Priori ◽

Log Normal ◽

Log Normal Distribution

This study is focused on enhancing the informativity of optical measurement techniques for particulate matter. The problem is that the description of particulate matter with bimodal and multimodal distributions by an a priori defined analytical function of particle size distribution (for example, a log-normal distribution) is not accurate enough. Here, we explore if experimental data can be approximated by a multivariable function of particle size distribution instead of using the a priori defined log-normal distribution. For the comparison of the approximation results, experiments are conducted on standard samples with granulometric compositions OGS-01LM and OGS-08LM separately and jointly in a mix. The experimental data are recorded by a high-selectivity turbidimetric technique in water suspensions of these samples. The purpose of this study is to present the measurement results as a distribution function that enables one to identify more accurately the particle-size distribution profile and the corresponding disperse characteristics of the aerosol in question when measuring parameters of disperse media by optical techniques. The main objective of this work is to develop, implement and verify a search algorithm for the particle-size distribution function by way of a multi-parameter function. We show that the solution to the problem proposed herein is more universal because it allows slow and fast processes in suspensions and aerosols to be examined with a lower error. The algorithm can be applied to the problems which are based on solving first-kind Fredholm equations.

Download Full-text