CFD analysis of a multiplatform catamaran by means of a web-based application: Experimental data comparison for a fully automated analysis process

Annular seals are used in turbomachinery to reduce secondary flow between regions of high and low pressure. In a vibrating rotor system, the non-axisymmetric pressure field developed in the small clearance between the rotor and the seal generate reactionary forces that can affect the stability of the entire rotor system. Traditionally, two analyses have been used to study the fluid flow in seals, bulk-flow analysis and computational fluid dynamics (CFD). Bulk-flow methods are computational inexpensive, but solve simplified equations that rely on empirically derived coefficients and are moderately accurate. CFD analyses generally provide more accurate results than bulk-flow codes, but solution time can vary between days and weeks. For gas damper seals, these analyses have been developed with the assumption that the flow can be treated as isothermal. Some experimental studies show that the difference between the inlet and outlet temperature temperatures is less than 5% but initial CFD studies show that there can be a significant temperature change which can have an effect on the density field. Thus, a comprehensive analysis requires the solution of an energy equation. Recently, a new hybrid method that employs a CFD analysis for the base state, unperturbed flow and a bulk-flow analysis for the first order, perturbed flow has been developed. This method has shown to compare well with full CFD analysis and experimental data while being computationally efficient. In this study, the previously developed hybrid method is extended to include the effects of non-isothermal flow. The hybrid method with energy equation is then compared with the isothermal hybrid method and experimental data for several test cases of hole-pattern seals and the importance of the use of energy equation is studied.

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CFD Analysis of C-D Nozzle Compared with Theoretical & Experimental Data

INCAS BULLETIN ◽

10.13111/2066-8201.2018.10.2.6 ◽

2018 ◽

Vol 10 (2) ◽

pp. 53-64

Author(s):

KEIR Stewart ◽

◽

IVES Rob ◽

HAMAD Faik ◽

◽

...

Keyword(s):

Experimental Data ◽

Cfd Analysis

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KiMoSys 2.0: an upgraded database for submitting, storing and accessing experimental data for kinetic modeling

Database ◽

10.1093/database/baaa093 ◽

2020 ◽

Vol 2020 ◽

Author(s):

Hugo Mochão ◽

Pedro Barahona ◽

Rafael S Costa

Keyword(s):

Experimental Data ◽

Metabolic Networks ◽

Model Simulation ◽

Web Interface ◽

Concentration Data ◽

Web Based ◽

Share Data ◽

Visualization Tools ◽

Filter Mechanism ◽

Machine Readable

Abstract The KiMoSys (https://kimosys.org), launched in 2014, is a public repository of published experimental data, which contains concentration data of metabolites, protein abundances and flux data. It offers a web-based interface and upload facility to share data, making it accessible in structured formats, while also integrating associated kinetic models related to the data. In addition, it also supplies tools to simplify the construction process of ODE (Ordinary Differential Equations)-based models of metabolic networks. In this release, we present an update of KiMoSys with new data and several new features, including (i) an improved web interface, (ii) a new multi-filter mechanism, (iii) introduction of data visualization tools, (iv) the addition of downloadable data in machine-readable formats, (v) an improved data submission tool, (vi) the integration of a kinetic model simulation environment and (vii) the introduction of a unique persistent identifier system. We believe that this new version will improve its role as a valuable resource for the systems biology community. Database URL: www.kimosys.org

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A web-based, branching logic questionnaire for the automated classification of migraine

10.1101/369827 ◽

2018 ◽

Author(s):

Eric A. Kaiser ◽

Aleksandra Igdalova ◽

Geoffrey K. Aguirre ◽

Brett Cucchiara

Keyword(s):

Migraine Without Aura ◽

Large Scale ◽

Automated Analysis ◽

Automated Classification ◽

Online Questionnaire ◽

Demographic Differences ◽

Web Based ◽

Online Evaluation ◽

Automated Algorithm

AbstractObjectiveTo identify migraineurs and headache-free individuals with an online questionnaire and automated analysis algorithm.MethodsWe created a branching-logic, web-based questionnaire—the Penn Online Evaluation of Migraine (POEM)—to obtain standardized headache history from a previously studied cohort. Responses were analyzed with an automated algorithm to assign subjects to one of several categories based on ICHD-3 (beta) criteria. Following a pre-registered protocol, this result was compared to prior diagnostic classification by a neurologist following a direct interview.ResultsOf 118 subjects contacted, 90 (76%) completed the questionnaire; of these 31 were headache-free, 29 migraine without aura (MwoA), and 30 migraine with aura (MwA). Mean age was 41 ± 6 years and 76% were female. There were no significant demographic differences between groups. The median time to complete the questionnaire was 2.5 minutes. Sensitivity of the POEM tool was 42%, 59%, and 70%, and specificity was 100%, 84%, and 94% for headache-free, MwoA, and MwA, respectively. Sensitivity and specificity of the POEM tool for migraine overall (with or without aura), was 83% and 90%, respectively.ConclusionsThe POEM web-based questionnaire, and associated analysis routines, identifies headache-free and migraine subjects with good specificity. It may be useful for classifying subjects for large-scale research studies.Trial Registration:https://osf.io/sq9ef

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Exploring the Determinants Affecting Academics' Knowledge-Sharing Behavior in United Arab Emirates Public Universities

Contemporary Knowledge and Systems Science - Advances in Knowledge Acquisition, Transfer, and Management ◽

10.4018/978-1-5225-5655-8.ch007 ◽

2018 ◽

pp. 151-191 ◽

Cited By ~ 1

Author(s):

Huda Skaik ◽

Roslina Othman

Keyword(s):

Knowledge Sharing ◽

United Arab Emirates ◽

Structural Model ◽

Measurement Model ◽

Subjective Norms ◽

Web Based ◽

Analysis Process ◽

Knowledge Sharing Behavior ◽

The Relationship ◽

Sharing Behavior

This chapter investigates knowledge-sharing practice among academics, examines the relationship between knowledge-sharing behavior and its predictors based on theory of planned behavior, and identifies the motivators and barriers affecting these predictors. Data were collected using a web-based questionnaire. Using SPSS and PLS-SEM, the analysis process involved (1) measuring the extent of knowledge sharing practice, (2) assessing the measurement model, (3) assessing the structural model, (4) testing the hypotheses, (5) validating research model fit. Results showed (1) great extent of knowledge-sharing practice, (2) knowledge-sharing behavior is significantly affected by intention, which is affected by attitude, subjective norms, self-efficacy, but not affected by controllability, (3) attitude is positively affected by trust and reputation as motivators of knowledge sharing, while controllability is negatively affected by lack of time and poor communication as barriers of knowledge sharing. This is the first research on knowledge-sharing behavior in higher education in UAE.

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In-beam tests of a PET demonstrator (LAPD) for hadrontherapy beam ballistic control: data comparison to Geant4 Monte-Carlo predictions

EPJ Web of Conferences ◽

10.1051/epjconf/202022509005 ◽

2020 ◽

Vol 225 ◽

pp. 09005

Author(s):

Sébastien Binet ◽

Arthur Bongrand ◽

Emmanuel Busato ◽

Christophe Insa ◽

Daniel Lambert ◽

...

Keyword(s):

Experimental Data ◽

Monte Carlo ◽

Mechanical Characteristics ◽

Ion Beams ◽

Cancer Treatments ◽

Control Data ◽

Data Comparison ◽

Large Acceptance ◽

Ballistic Control

This paper describes a small prototype of an in beam PET like detector, named ”Large Acceptance Pixelized Detector” (LAPD), developed to test technical concepts for the ion range control in the context of cancer treatments using proton or ion beams. The mechanical characteristics of this detector together with the read-out electronics are first presented. Then, results of a first experiment, performed on a 65 MeV proton beamline, are reported. Finally, we discuss the ability of Geant4 Monte-Carlo to reproduce the experimental data.

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Assessment of CFD Approaches for Next-Generation Combustor Design

ASME 2014 Gas Turbine India Conference ◽

10.1115/gtindia2014-8361 ◽

2014 ◽

Cited By ~ 1

Author(s):

Kumud Ajmani ◽

Hukam C. Mongia ◽

Phil Lee

Keyword(s):

Experimental Data ◽

Direct Injection ◽

Operating Conditions ◽

Reacting Flow ◽

Cfd Analysis ◽

Next Generation ◽

Lean Direct Injection ◽

Liquid Spray ◽

Exit Temperature ◽

Computational Predictions

An effort was undertaken to perform CFD analysis of fluid flow in Lean-Direct Injection (LDI) combustors with axial swirl-venturi elements for next-generation LDI-2 design. The National Combustion Code (NCC) developed at NASA Glenn Research Center was used to perform reacting flow computations on an LDI-2 combustor configuration with thirteen injector elements arranged in four fuel stages. Reacting computations were performed with a consistent approach for mesh-optimization, liquid spray modeling and kinetics modeling. Computational predictions of Emissions Index (EINOx) and combustor exit temperature were compared with two sets of experimental data at medium and high-power operating conditions, for two different pressure-drop conditions in the combustor. The NCC simulations predicted the combustor exit temperature to within 1–2% of experimental data. The accuracy of the EINOx predictions from the NCC simulations was within 10% to 30% of experimental data.

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