970 research outputs found
Combustion and Exhaust Emission Characteristics of Low Swirl Injector
This document is the Accepted Manuscript version of the following article: Yangbo Deng, Hongwei Wu, and Fengmin Su, âCombustion and exhaust emission characteristics of low swirl injectorâ, 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 âWâ 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 âWâ type flame into the âbroomâ 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
A Review on House Design with Energy Saving System in the UK
This document is the Accepted Manuscript version of the following article: Y. Xie, M. S. Gilmour, Y. Yuan, H. Jin, and H. Wu, âA review on house design with energy saving system in the UKâ, Renewable and Sustainable Energy Reviews, Vol. 71, pp. 29-52, first published online 10 January 2017. Under embargo. Embargo end date: 10 January 2018. 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.app/thermaleng.2017.01.003 © 2017 Elsevier Ltd. All rights reserved.As part of EU incentives, the UK government have set ambitious environmental targets relating to energy consumption including a reduction of carbon emissions of 80% by 2050. The use of various technologies can help meet these targets as well as providing a secure energy source for the UK in the future. This research took the UK as a case study and investigated where reduction measures are most suited to reduce energy consumption. This paper presents a review on the current state-of-the-art on the domestic technology available, in particular solar energy, heat pumps, phase changing materials (PCMs) and micro combined heat and power (micro-CHP) systems, aiming at identifying research and development opportunities for energy saving in these fields. Furthermore, the financial as well as environmental aspects are assessed as these are the two key considerations of typical household. A typical UK house design, including the floor plan, is created through the use of computer aided design (CAD) software. The house design gives a payback period between 8.7 years at best and 11.6 years at worst.Peer reviewe
Modeling Solubility of Nitrogen in Clean Fire Extinguishing Agent by Peng-Robinson Equation of State and a Correlation of Henryâs Law Constants
This document is the Accepted Manuscript version of the following article: Mengdong Chen, Yongqi Xie, Hongwei Wu, Shang Shi, and Jianzu Yu, âModelling solubility of Nitrogen in clean fire extinguishing agent by Peng-Robinson equation of state and a correlation of Henryâs law constantsâ, Applied Thermal Engineering, Vol. 110, pp. 457-468, first published online 29 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.2016.08.179 © 2016 Elsevier Ltd. All rights reserved.Nitrogen is usually used to increase the total pressure of the fluid in aircraft fire suppression bottle. The amount of nitrogen required in the bottle is a significant factor to assure complete and effective discharge into the protected area and it depends on the solubility of the nitrogen in the fire extinguishing agent. In this article, the Peng-Robinson equation of state (PR EOS) including both the classical van der Waals mixing rule and the Wong-Sandler mixing rule is utilized to correlate the Gas-Liquid Equilibrium (GLE) data from available open published literature and to analyze the solubility of nitrogen in halon alternatives such as HFC227ea (C3HF7), CF3I, FC218 (C3F8), and HFC125 (C2HF5) with Halon1301 (CF3Br) as a reference. A new method is proposed to compute the adjustable interaction parameters in the van der Waals mixing rule and in the Wong-Sandler mixing rule based on the measurements of nitrogen required to pressurize the fire suppression bottle to a specified equilibrium pressure at room temperature. Results show that the PR EOS reproduces the GLE data very well with both van der Waals mixing rule and the Wong-Sandler mixing rule and it is then utilized to predict the temperature dependence of the Henryâs law constants of nitrogen dissolved in the fire extinguishing agents. The PR EOS with van der Waals mixing rule is much more appropriate for determining the Henryâs constants than that with the Wong-Sandler mixing rule and the results calculated by the current model are used to establish a new correlation for the Henryâs law constants. This correlation will be very helpful for fire extinguishing bottle designers to acquire the pressure-temperature relationships for the mixture of nitrogen and agents.Peer reviewe
Non-steady experimental investigation on an integrated thermal management system for power battery with phase change materials
This document is the Accepted Manuscript version of the following article: Shang Shi, Yongqi Xie, Ming Li, Yanping Yuan, Jianzu Yu, Hongwei Wu, Bin Liu, Nan Liu, âNon-steady experimental investigation on an integrated thermal management system for power battery with phase change materialsâ, Energy Conversion and Management, Vol. 138, pp. 84-96, first published online 10 February 2017. Under embargo. Embargo end date: 10 February 2018. 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.enconman.2017.01.069 © 2017 Elsevier Ltd. All rights reserved.A large amount of heat inside the power battery must be dissipated to maintain the temperature in a safe range for the hybrid power train during high-current charging/discharging processes. In this article, a combined experimental and theoretical study has been conducted to investigate a newly designed thermal management system integrating phase change material with air cooling. An unsteady mathematical model was developed for the battery with the integrated thermal management system. Meanwhile, the heat generation power, thermal resistance, and time constant were calculated. The effect of several control parameters, such as thermal resistance, initial temperature, melting temperature and ambient temperature, on the performance of the integrated thermal management system were analyzed. The results indicated that: (1) the calculated temperature rise of the battery was in good agreement with the experimental data. The appropriate operation temperature of the battery was attained by the action of the phase change storage energy unit which is composed of copper foam and n-Eicosane, (2) the remarkable decrease of the battery temperature can be achieved by reducing the convection thermal resistance or increasing the conductivity of the phase change storage energy unit, where the latter could be the better option due to no additional energy consumption. When convective resistance and thermal resistance between the battery surface and the phase change storage energy unit are less than 2.03 K/W and 1.85 K/W, respectively, the battery will not exceed the safety temperature under extreme condition, (3) the temperature rise declines with the decrease of the melting temperature or with the increase of the ambient temperature. It could be possible that the battery temperature exceeds the safety temperature for the high ambient temperature, (4) even if the phase change material is completely melted, the integrated thermal management system can still maintain the battery temperature within the safe range because of the air cooling.Peer reviewe
A Curriculum for a Master of Science in Information Quality
The first Master of Science in Information Quality (IQ) degree is designed and being offered to prepare students for careers in industry and government as well as advanced graduate studies. The curriculum is guided by the Model Curriculum and Guidelines for Graduate Degree Programs in Information Systems, which are endorsed by the Association for Computing Machinery and the Association for Information Systems. The curriculum integrates two key educational innovations: (1) an interdisciplinary approach to curriculum design, and (2) a balance between theoretical rigor and practical relevance. In response to the demand from industry, the curriculum aims to educate students who can lead the effort to solve current and future information quality problems. As such, problem-based learning is balanced with foundation-building learning to effectively deliver the intellectual contents of the curriculum. Much of the individual course content is based on cumulated research results and practices developed over the last two decades. The curriculum is designed to balance information quality theory with industry best practices using modern tools and technology. It includes the skill sets that are critical to succeed as IQ professionals. Since IQ is an inter-disciplinary field, the curriculum draws upon total quality management, database, core knowledge of IQ, change management, project management, and IQ policy and strategy. The courses are delivered using case studies, hands-on laboratories, theory building, and team projects to enhance the student\u27s learning experience. Upon completing the program, students will be equipped with sufficient breadth and depth in the IQ field to solve real world problems and pursue further studies
Statistical Properties of Interacting Bose Gases in Quasi-2D Harmonic Traps
The analytical probability distribution of the quasi-2D (and purely 2D) ideal
and interacting Bose gas are investigated by using a canonical ensemble
approach. Using the analytical probability distribution of the condensate, the
statistical properties such as the mean occupation number and particle number
fluctuations of the condensate are calculated. Researches show that there is a
continuous crossover of the statistical properties from a quasi-2D to a purely
2D ideal or interacting gases. Different from the case of a 3D Bose gas, the
interaction between atoms changes in a deep way the nature of the particle
number fluctuations.Comment: RevTex, 10pages, 4 figures, E-mail: [email protected]
Search for via the transition at LHCb and factory
It is interesting to study the characteristics of the whole family of
which contains two different heavy flavors. LHC and the proposed factory
provide an opportunity because a large database on the family will be
achieved. and its excited states can be identified via their decay modes.
As suggested by experimentalists, is not easy to be
clearly measured, instead, the trajectories of and occurring in
the decay of () can be unambiguously
identified, thus the measurement seems easier and more reliable, therefore this
mode is more favorable at early running stage of LHCb and the proposed
factory. In this work, we calculate the rate of
in terms of the QCD multipole-expansion and the numerical results indicate that
the experimental measurements with the luminosity of LHC and factory are
feasible.Comment: 12 pages, 1 figures and 4 tables, acceptted by SCIENCE CHINA Physics,
Mechanics & Astronomy (Science in China Series G
Probing the course of cosmic expansion with a combination of observational data
We study the cosmic expansion history by reconstructing the deceleration
parameter from the SDSS-II type Ia supernova sample (SNIa) with two
different light curve fits (MLCS2k2 and SALT-II), the baryon acoustic
oscillation (BAO) distance ratio, the cosmic microwave background (CMB) shift
parameter, and the lookback time-redshift (LT) from the age of old passive
galaxies. Three parametrization forms for the equation of state of dark energy
(CPL, JBP, and UIS) are considered. Our results show that, for the CPL and the
UIS forms, MLCS2k2 SDSS-II SNIa+BAO+CMB and MLCS2k2 SDSS-II SNIa+BAO+CMB+LT
favor a currently slowing-down cosmic acceleration, but this does not occur for
all other cases, where an increasing cosmic acceleration is still favored.
Thus, the reconstructed evolutionary behaviors of dark energy and the course of
the cosmic acceleration are highly dependent both on the light curve fitting
method for the SNIa and the parametrization form for the equation of state of
dark energy.Comment: 19 pages, 6 figures, accepted for publication in JCA
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