456 research outputs found

    Three-Dimensional Modelling and Simulation of the Ice Accretion Process on Aircraft Wings

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    © 2018 Chang S, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.In this article, a new computational method for the three-dimensional (3D) ice accretion analysis on an aircraft wing is formulated and validated. The two-phase flow field is calculated based on Eulerian-Eulerian approach using standard dispersed turbulence model and second order upwind differencing with the aid of commercial software Fluent, and the corresponding local droplet collection efficiency, convective heat transfer coefficient, freezing fraction and surface temperature are obtained. The classical Messinger model is modified to be capable of describing 3D thermodynamic characteristics of ice accretion. Considering effects of runback water, which is along chordwise and spanwise direction, an extended Messinger method is employed for the prediction of the 3D ice accretion rates. Validation of the newly developed model is carried out through comparisons with available experimental ice shape and LEWICE codes over a GLC-305 wing under both rime and glaze icing conditions. Results show that good agreement is achieved between the current computational ice shapes and the compared results. Further calculations based on the proposed method over a M6 wing under different test conditions are numerically demonstrated.Peer reviewedFinal Published versio

    Combustion and Exhaust Emission Characteristics of Low Swirl Injector

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    This document is the Accepted Manuscript version of the following article: Yangbo Deng, Hongwei Wu, and Fengmin Su, ‘Combustion and exhaust emission characteristics of low swirl injector’, Applied Thermal Engineering, Vol. 110, pp. 171-180, first published online 28 August 2016. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/ The version of record is available online at doi: http://dx.doi.org/10.1016/j.applthermaleng.2016.08.169 © 2016 Elsevier Ltd. All rights reserved.The present experimental study aims to investigate the combustion and emission characteristics of the flow through a low swirl injector (LSI). An experimental study was carried out on the flame structure, the temperature distribution and the exhaust emission of low swirl pre-mixed combustion under the condition of different swirl number and different fuel composition. In order to qualitatively analyze the flame structure, the velocity distribution of the non-reacting flow through the LSI was measured using the particle image velocimetry (PIV) technique. Experimental results indicated that: (i) the LSI can generate a blue lift-off “W” type flame which consists of four clusters of flames connected together and holds up a long yellow pulsating flame, (ii) the blue flame structure converts the “W” type flame into the “broom” type flame and the distance between the front of the flame and the nozzle shortens with increasing swirl number, (iii) there exist high temperature region flanked by two peaks on the temperature profiles in the blue flame while uniform higher temperature in yellow pulsating flame, (iv) the NOx and CO emission level of the LSI mainly depends on the gas composition and thermal load.Peer reviewe

    Collaboratively Assessing Information Quality on the Web

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    The Web has become a large repository of information with varying qualities. Many users often consume information without knowing its quality. Although automatic methods can be used to obtain measurements of certain aspects of quality, they are not reliable and cannot measure all aspects of quality. Users can detect errors and reliably assess aspects of quality that cannot be measured by automatic methods. However, there is a lack of technology support for users to record and share their feedback. This research aims to develop technologies to allow users to collaboratively assess information quality on the Web. The solution combines the capabilities of machines and humans to obtain comprehensive, reliable, and scalable measurements of information quality. In this paper, the crucial user interaction component of the solution is presented. It uses a browser plug-in to allow users to rate and annotate any Web page and share ratings and annotations with other users

    Global Software Development Project

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    Global software development has become a common reality with the advent of off-shore development and the need to be close to markets. This type of development has posed some challenges faced by software development personals. In this research, we report a software development project that involves the collaboration of students from USA and China
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