Modeling Criteria for Scaled LNG Sloshing Experiments

1985 ◽  
Vol 107 (2) ◽  
pp. 272-280 ◽  
Author(s):  
R. L. Bass ◽  
E. B. Bowles ◽  
R. W. Trudell ◽  
J. Navickas ◽  
J. C. Peck ◽  
...  
Keyword(s):  
Natural Gas ◽  
Laboratory Test ◽  
Test Data ◽  
State Of The Art ◽  
Current Knowledge ◽  
Liquefied Natural Gas ◽  
Additional Research ◽  
Scale Modeling ◽  
Current State ◽  
Scaling Parameters

This paper presents an overview of the current state-of-the-art in scale modeling of liquefied natural gas sloshing in ship tanks. The numerous potentially significant scaling parameters are discussed in detail and laboratory test data illustrating the effects of the important scaling parameters are presented. In view of current knowledge, an indication of appropriate scaling criteria is presented and recommendations for additional research efforts are outlined.

Acceptance Testing of Liquefied Natural Gas Compressors

2015 ◽  
Author(s):  
Roger Nyquist ◽  
Mike Andrews ◽  
Andrew Hunter ◽  
Oyuna Myagmar
Keyword(s):  
Mach Number ◽  
Natural Gas ◽  
Test Data ◽  
Density Ratio ◽  
Liquefied Natural Gas ◽  
Inlet Pressure ◽  
Data Conversion ◽  
Acceptance Testing ◽  
Ambient Temperatures ◽  
Similarity Laws

The majority of natural gas compressors operate on gas mixtures with molecular weights (MW) less than air. For these machines, performance acceptance tests are run on air at reduced speed. For multistage compressors, each stage is tested individually. The test speeds and inlet temperatures are selected to closely match the inlet to exit density ratios and the machine Mach numbers per the ASME PTC10 test code. The specified test inlet pressure (limited by the test variable speed motor power capacity) is always high enough to assure that the test Reynolds number is above the required PTC10 minimum; the density ratio and machine Mach number do not depend on inlet pressure. The air test data is converted to the specified natural gas conditions using similarity laws, and an in-house stage matching program is used to determine the overall machine performance. For compressors used in liquefied natural gas (LNG) transport, the MW of the natural gas mixture is lower than air. However, the inlet temperatures are so low that an air test at typical ambient temperatures needs to be run at a speed higher than design to closely match density and machine Mach number ratios. It is impractical to run air tests at higher than design speeds (especially for 60 Hz machines), thus these machines are tested on air at design speed. As before, the air test data is reduced to the specified natural gas conditions using the similarity laws. An additional “compressibility” correction is made to account for the mismatch of density ratio between test and design conditions. Running a test at lower than the required PTC10 speed means that the test density ratio will be lower than the corrected density ratio and the stage would pass more flow than the test data conversion indicates. The method used to account for the density ratio mismatch, i.e. a “compressibility” correction is discussed in detail in this paper.

scholarly journals Semi-analytical models of hydroelastic sloshing impact in tanks of liquefied natural gas vessels

2011 ◽  
Vol 369 (1947) ◽  
pp. 2920-2941 ◽  
Author(s):  
I. Ten ◽  
Š. Malenica ◽  
A. Korobkin
Keyword(s):  
Natural Gas ◽  
State Of The Art ◽  
Liquefied Natural Gas ◽  
Analytical Models ◽  
Structural Behaviour ◽  
Hydrodynamic Models ◽  
Basic Principles ◽  
Structural Part ◽  
The Impact ◽  
Violent Sloshing

The present paper deals with the methods for the evaluation of the hydroelastic interactions that appear during the violent sloshing impacts inside the tanks of liquefied natural gas carriers. The complexity of both the fluid flow and the structural behaviour (containment system and ship structure) does not allow for a fully consistent direct approach according to the present state of the art. Several simplifications are thus necessary in order to isolate the most dominant physical aspects and to treat them properly. In this paper, choice was made of semi-analytical modelling for the hydrodynamic part and finite-element modelling for the structural part. Depending on the impact type, different hydrodynamic models are proposed, and the basic principles of hydroelastic coupling are clearly described and validated with respect to the accuracy and convergence of the numerical results.

scholarly journals Trick or Treating in Forensics—The Challenge of the Saliva Microbiome: A Narrative Review

2020 ◽  
Vol 8 (10) ◽  
pp. 1501
Author(s):  
Gabriella D’Angiolella ◽  
Pamela Tozzo ◽  
Sarah Gino ◽  
Luciana Caenazzo
Keyword(s):  
Microbial Community ◽  
Systematic Reviews ◽  
State Of The Art ◽  
Current Knowledge ◽  
Narrative Review ◽  
Oral Microbiome ◽  
Current State ◽  
Microbial Analysis ◽  
Specific Factors ◽  
Meta Analyses

The oral microbiome harbours microbial community signatures that differ among individuals, highlighting that it could be highly individualizing and potentially unique to each individual. Therefore, the oral microbial traces collected in crime scenes could produce investigative leads. This narrative review will describe the current state-of-the-art of how the salivary microbiome could be exploited as a genetic signature to make inferences in the forensic field. This review has been performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Guidelines. Even if further studies are needed to relate the variation in the oral microbiome to specific factors, in order to understand how the salivary microbiome is influenced by an individual’s lifestyle, by reviewing the studies published so far, it is clear that the oral microbial analysis could become a useful forensic tool. Even if promising, caution is required in interpreting the results and an effort to direct research towards studies that fill the current knowledge gaps is certainly useful.

Pressure Suppression Containment Design—Current State of the Art

1969 ◽  
Vol 91 (1) ◽  
pp. 13-20 ◽  
Author(s):  
D. R. Miller
Keyword(s):  
Analytical Model ◽  
Test Data ◽  
State Of The Art ◽  
Nuclear Reactors ◽  
Current State ◽  
Graphical Technique ◽  
Containment Pressure

A summary of the thermodynamic design limits for pressure suppression containments for nuclear reactors is presented. Those parameters which must adhere to tested values are tabulated and discussed. An analytical model is described and is shown to accurately predict the existing test data. A graphical technique for predicting the transient peak containment pressure, based on the model, is presented for use in containment design.

RUSSIAN LNG IN THE GLOBAL MARKET: FEATURES, PROSPECTS AND BARRIERS

2020 ◽  
Vol 13 (4) ◽  
pp. 199-206
Author(s):  
M.V. Chernyaev ◽  
◽  
D.F. Kudriakov ◽  
Keyword(s):  
Natural Gas ◽  
Russian Federation ◽  
Global Market ◽  
Liquefied Natural Gas ◽  
Energy Resources ◽  
Market Development ◽  
Current Trends ◽  
Current State ◽  
The World ◽  
The Russian Federation

The present scientific research examines the current state of the Liquefied Natural Gas (LNG) market, as well as the role and place of the Russian energy resources on the world stage. The article highlights the features of the Russian LNG market development, the existing barriers and prospects. The work includes a dynamic analysis of the global market conditions, current trends and emerging risks caused by modern political and economic realities. In conclusion, the authors suggested a set of measures for increasing competitiveness of the Russian Federation in the global LNG market.

Behavioral Genetics: Concepts for Research and Practice in Language Development and Disorders

1995 ◽  
Vol 38 (5) ◽  
pp. 1126-1142 ◽  
Author(s):  
Jeffrey W. Gilger
Keyword(s):  
Language Development ◽  
Behavioral Genetics ◽  
State Of The Art ◽  
Genetic Research ◽  
Great Promise ◽  
Behavioral Genetic ◽  
Fine Grained ◽  
Future Goals ◽  
Current State ◽  
Research Designs

This paper is an introduction to behavioral genetics for researchers and practioners in language development and disorders. The specific aims are to illustrate some essential concepts and to show how behavioral genetic research can be applied to the language sciences. Past genetic research on language-related traits has tended to focus on simple etiology (i.e., the heritability or familiality of language skills). The current state of the art, however, suggests that great promise lies in addressing more complex questions through behavioral genetic paradigms. In terms of future goals it is suggested that: (a) more behavioral genetic work of all types should be done—including replications and expansions of preliminary studies already in print; (b) work should focus on fine-grained, theory-based phenotypes with research designs that can address complex questions in language development; and (c) work in this area should utilize a variety of samples and methods (e.g., twin and family samples, heritability and segregation analyses, linkage and association tests, etc.).

Schizophrenia Research: Current State of the Art

1976 ◽  
Vol 21 (7) ◽  
pp. 497-498
Author(s):  
STANLEY GRAND
Keyword(s):  
State Of The Art ◽  
Current State
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