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An Adaptive Feed-Forward Phase Locked Loop For Grid Synchronization Of Renewable Energy Systems Under Wide Frequency Deviations, Aravind Chellachi Kathiresan, Jeyaraj Pandiarajan, Asokan Sivaprakash, Thanikanti Sudhakar Babu, Md Rabiul Islam Jan 2020

An Adaptive Feed-Forward Phase Locked Loop For Grid Synchronization Of Renewable Energy Systems Under Wide Frequency Deviations, Aravind Chellachi Kathiresan, Jeyaraj Pandiarajan, Asokan Sivaprakash, Thanikanti Sudhakar Babu, Md Rabiul Islam

Faculty of Engineering and Information Sciences - Papers: Part B

Synchronization is a crucial problem in the grid-connected inverter’s control and operation. A phase-locked loop (PLL) is a typical grid synchronization strategy, which ought to have a high resistance to power system uncertainties since its sensitivity influences the generated reference signal. The traditional PLL catches the phase and frequency of the input signal via the feedback loop filter (LF). In general, to enhance the steady-state capability during distorted grid conditions generally, a filter tuned for nominal frequency is used. This PLL corrects large frequency deviations around the nominal frequency, which increases the PLL’s locking time. Therefore, this paper presents an …


A Novel Empirical Heat Transfer Model For A Solar Thermal Storage Process Using Phase Change Materials, Yu Bie, Ming Li, Fei Chen, Grzegorz Krolczyk, Lin Yang, Zhixiong Li, Weihua Li Jan 2019

A Novel Empirical Heat Transfer Model For A Solar Thermal Storage Process Using Phase Change Materials, Yu Bie, Ming Li, Fei Chen, Grzegorz Krolczyk, Lin Yang, Zhixiong Li, Weihua Li

Faculty of Engineering and Information Sciences - Papers: Part B

Numerical and experimental analyses are often used to evaluate the solar thermal system with latent heat thermal energy storage (LHTES). However, the relationship between the numerical simulation and actual heat transfer process is still unclear. This work compares the simulated average temperature of two different phase change materials (PCMs) with experimental result at different operation conditions for the purpose of developing a temperature correction model. A novel empirical heat transfer model is then established to improve the simulation accuracy of PCM-based solar thermal systems. The contributions of this work include that (1) the system performance could be evaluated by the …


Mixed Convection Of Non-Newtonian Nanofluid In An H-Shaped Cavity With Cooler And Heater Cylinders Filled By A Porous Material: Two Phase Approach, Zhixiong Li, Pouya Barnoon, Davood Toghraie, Reza Balali Dehkordi, Masoud Afrand Jan 2019

Mixed Convection Of Non-Newtonian Nanofluid In An H-Shaped Cavity With Cooler And Heater Cylinders Filled By A Porous Material: Two Phase Approach, Zhixiong Li, Pouya Barnoon, Davood Toghraie, Reza Balali Dehkordi, Masoud Afrand

Faculty of Engineering and Information Sciences - Papers: Part B

In the present problem, two-phase mixed convection of a non-Newtonian nanofluid in a porous H-shaped cavity is studied. Inside the enclosure there are four rotating cylinders, using the Boussinesq approximation, mixed convection is created. Nanofluid includes H2O + 0.5% CMC and copper oxide nanoparticles. The mixture model was used to model physical phenomena. Different aspect ratios were used in order to achieve the best heat transfer rate. The Darcy and Richardson numbers ranges are 10−4 ≤ Da ≤ 10−2 and 1 ≤ Ri ≤ 100 respectively. Also, the aspect ratio and dimensionless angular velocities of cylinders ranges are 1.4 ≤ …


Solar-Assisted Hvac Systems With Integrated Phase Change Materials, Zhenjun Ma, Haoshan Ren, Wenye Lin, Shugang Wang Jan 2018

Solar-Assisted Hvac Systems With Integrated Phase Change Materials, Zhenjun Ma, Haoshan Ren, Wenye Lin, Shugang Wang

Faculty of Engineering and Information Sciences - Papers: Part B

Solar-assisted heating, ventilation and air-conditioning (HVAC) systems are receiving increasing attention. This chapter presents the development of HVAC systems with integrated solar photovoltaic-thermal (PVT) collectors and phase change materials (PCMs) to reduce building energy consumption while providing satisfactory indoor thermal comfort. PVT collectors, which can generate both thermal energy and electricity simultaneously, are a promising technology for developing high-performance buildings. As solar energy is intermittent, the integration of phase change materials (PCMs) with PVTdriven HVAC systems can provide an opportunity to effectively utilise solar energy and maximise the performance of HVAC systems. The results showed that the coefficient of performance …


Development Of Microencapsulated Phase Change Material For Solar Thermal Energy Storage, Weiguang Su, Jo Darkwa, Georgios Kokogiannakis Jan 2017

Development Of Microencapsulated Phase Change Material For Solar Thermal Energy Storage, Weiguang Su, Jo Darkwa, Georgios Kokogiannakis

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper a novel microencapsulated phase change material (MF-3) has been developed and tested for solar assisted hot water storage systems. Even though the morphology of the sample was affected by the type of emulsifier used for fabrication it recorded the highest energy storage capacity of 126 kJ/kg with encapsulation efficiency of 97.4% as compared with other developed samples. For the purpose of assessing its thermal effectiveness it was theoretically evaluated in a compacted fixed bed TES unit and found to be capable of achieving a higher energy storage density as well as relatively smaller physical storage size than …


Strain-Induced Ferrite Formation And Its Effect On Mechanical Properties Of A Dual Phase Steel Produced Using Laboratory Simulated Strip Casting, Zhiping Xiong, Ahmed A. Saleh, Andrii Kostryzhev, Elena V. Pereloma Jan 2017

Strain-Induced Ferrite Formation And Its Effect On Mechanical Properties Of A Dual Phase Steel Produced Using Laboratory Simulated Strip Casting, Zhiping Xiong, Ahmed A. Saleh, Andrii Kostryzhev, Elena V. Pereloma

Faculty of Engineering and Information Sciences - Papers: Part B

Thermo-mechanical processing of a strip cast dual phase (DP) steel was carried out using a Gleeble thermo-mechanical simulator. The effect of deformation temperatures in the range from 1050 to 700 °C on the microstructure evolution was investigated using optical, scanning and transmission electron microscopy along with electron backscattering diffraction (EBSD). Strain-induced ferrite (SIF) formation was observed following austenite deformation (∼0.41 reduction) in the 800–700 °C temperature range, leading to a ferrite grain refinement down to 3.1 ± 2.3 μm. A novel segmentation procedure was applied to separate selected EBSD maps into polygonal ferrite, SIF and second phase regions (bainite/martensite). Following …


Heat Transfer Analysis Of An Integrated Double Skin Facade And Phase Change Material Blind System, Yilin Li, Jo Darkwa, Georgios Kokogiannakis Jan 2017

Heat Transfer Analysis Of An Integrated Double Skin Facade And Phase Change Material Blind System, Yilin Li, Jo Darkwa, Georgios Kokogiannakis

Faculty of Engineering and Information Sciences - Papers: Part B

In this study, the heat transfer in an integrated double skin facade (DSF) and phase change material (PCM) blind system has been theoretically analysed. Both heat transfer and airflow models with CFD methods have been developed for the integrated DSF and PCM blind system. Data from an existing typical DSF building have been obtained in order to define input parameters for the simulation exercise and validate the numerical models. The temperature and velocity fields in DSF with the PCM blind system has been predicted under overheating scenario using the ANSYS Workbench FLUENT software and been compared with case of conventional …


Performance Evaluation Of A Novel Frost-Free Air-Source Heat Pump Integrated With Phase Change Materials (Pcms) And Dehumidification, Zhihua Wang, Fenghao Wang, Zhenjun Ma, Chun Li, Yibo Xu Jan 2017

Performance Evaluation Of A Novel Frost-Free Air-Source Heat Pump Integrated With Phase Change Materials (Pcms) And Dehumidification, Zhihua Wang, Fenghao Wang, Zhenjun Ma, Chun Li, Yibo Xu

Faculty of Engineering and Information Sciences - Papers: Part B

Air-source heat pump (ASHP) has been widely used in domestic and commercial buildings because of its energy savings, high efficiency and environmental friendliness. However, the heating capacity of an ASHP system is greatly influenced by the frost accumulation on the surface of the outdoor exchanger. To solve this problem, a novel frost-free ASHP system, integrating with Phase Change Materials (PCMs) and dehumidification, has been developed. In this paper, the schematic design of this system is first presented. The effect of the match relationship between the desiccant materials and PCM thermal energy storage on the performance of the novel system is …


Preparation Of Microencapsulated Phase Change Materials (Mepcm) For Thermal Energy Storage, Weiguang Su, Jo Darkwa, Georgios Kokogiannakis, Tongyu Zhou, Yilin Li Jan 2017

Preparation Of Microencapsulated Phase Change Materials (Mepcm) For Thermal Energy Storage, Weiguang Su, Jo Darkwa, Georgios Kokogiannakis, Tongyu Zhou, Yilin Li

Faculty of Engineering and Information Sciences - Papers: Part B

Microencapsulated phase change materials (MEPCM) could be used for energy saving applications in buildings due to their relatively high energy storage capacities at constant temperature, which could passively reduce peak cooling loads in summer. In this study, poly(methyl methacrylate-co-methacrylic acid) (PMMA-MAA) was used as a shell material to fabricate MEPCM by crosslinking methyl methacrylate (MMA) and methacrylic acid (MAA) through in-situ suspension-like polymerization method. The effects of initiator weight percentage and the ratio of shell monomers for the preparation of MEPCM were also investigated. The experimental results showed that the best MEPCM sample was achieved with a shell monomer weight …


Effect Of Deformation On Microstructure And Mechanical Properties Of Dual Phase Steel Produced Via Strip Casting Simulation, Zhiping Xiong, Andrii Kostryzhev, Nicole Stanford, Elena V. Pereloma Jan 2016

Effect Of Deformation On Microstructure And Mechanical Properties Of Dual Phase Steel Produced Via Strip Casting Simulation, Zhiping Xiong, Andrii Kostryzhev, Nicole Stanford, Elena V. Pereloma

Faculty of Engineering and Information Sciences - Papers: Part A

The strip casting is a recently appeared technology with a potential to significantly reduce energy consumption in steel production, compared to hot rolling and cold rolling. However, the quantitative dependences of the steel microstructure and mechanical properties on strip casting parameters are unknown and require investigation. In the present work we studied the effects of strain and interrupted cooling temperature on microstructure and mechanical properties in conventional dual phase steel (0.08C-0.81Si-1.47Mn-0.03Al wt%). The strip casting process was simulated using a Gleeble 3500 thermo-mechanical simulator. The steel microstructures were studied using optical, scanning and transmission electron microscopy. Mechanical properties were measured …


Nano-Enhanced Phase Change Materials For Improved Building Performance, Zhenjun Ma, Wenye Lin, Mohammed I. Sohel Jan 2016

Nano-Enhanced Phase Change Materials For Improved Building Performance, Zhenjun Ma, Wenye Lin, Mohammed I. Sohel

Faculty of Engineering and Information Sciences - Papers: Part A

Nano-enhanced phase change materials (PCMs) have attracted increasing attention to address one of the key barriers (i.e. low thermal conductivity) to the wide adoption of PCMs in many industrial applications. This paper discusses the generic problem and key issues associated with appropriately using this new class of materials in buildings for effective thermal management and improved energy performance. An overview on major recent development and application of nano-enhanced PCMs as thermal energy storage media is provided. A case study based on a PCM ceiling ventilation system integrated with solar photovoltaic thermal (PVT) collectors is then performed to evaluate the potential …


Mineral Phase Formation And Zinc Removal During Sintering Of Filter Cake Wastes, Zhe Wang, David J. Pinson, Sheng Chew, Brian J. Monaghan, Harold P. Rogers, Guangqing Zhang Jan 2016

Mineral Phase Formation And Zinc Removal During Sintering Of Filter Cake Wastes, Zhe Wang, David J. Pinson, Sheng Chew, Brian J. Monaghan, Harold P. Rogers, Guangqing Zhang

Faculty of Engineering and Information Sciences - Papers: Part A

A large amount of filter cake wastes are produced from the gas cleaning systems of blast furnace (BF) ironmaking and basic oxygen furnace (BOF) steelmaking processes. The filter cake wastes cannot be directly recycled through the ironmaking process due to the high zinc contents and are therefore, predominantly, stockpiled. The storage of filter cake wastes presents a long- Term environmental issue but also an opportunity to extract or recover the iron content, motivating a search for processes or technologies to allow their cost-effective recycling. In this study, two filter cake wastes from BlueScope Ltd. were sintered at 1 100-1 300°C …


Hydrostatic Compression Behavior And High-Pressure Stabilized Β-Phase In Γ-Based Titanium Aluminide Intermetallics, Klaus-Dieter Liss, Ken-Ichi Funakoshi, Rian J. Dippenaar, Yuji Higo, Ayumi Shiro, Mark H. Reid, Hiroshi Suzuki, Takahisa Shobu, Koichi Akita Jan 2016

Hydrostatic Compression Behavior And High-Pressure Stabilized Β-Phase In Γ-Based Titanium Aluminide Intermetallics, Klaus-Dieter Liss, Ken-Ichi Funakoshi, Rian J. Dippenaar, Yuji Higo, Ayumi Shiro, Mark H. Reid, Hiroshi Suzuki, Takahisa Shobu, Koichi Akita

Faculty of Engineering and Information Sciences - Papers: Part A

Titanium aluminides find application in modern light-weight, high-temperature turbines, such as aircraft engines, but suffer from poor plasticity during manufacturing and processing. Huge forging presses enable materials processing in the 10-GPa range, and hence, it is necessary to investigate the phase diagrams of candidate materials under these extreme conditions. Here, we report on an in situ synchrotron X-ray diffraction study in a large-volume press of a modern (α2 + γ) two-phase material, Ti-45Al-7.5Nb-0.25C, under pressures up to 9.6 GPa and temperatures up to 1686 K. At room temperature, the volume response to pressure is accommodated by the transformation γ → …


Correlation Between Zn-Rich Phase And Corrosion/Oxidation Behavior Of Sn-8zn-3bi Alloy, Xin Zhang, Chong Li, Zhiming Gao, Yongchang Liu, Zongqing Ma, Liming Yu, Hui Jun Li Jan 2016

Correlation Between Zn-Rich Phase And Corrosion/Oxidation Behavior Of Sn-8zn-3bi Alloy, Xin Zhang, Chong Li, Zhiming Gao, Yongchang Liu, Zongqing Ma, Liming Yu, Hui Jun Li

Faculty of Engineering and Information Sciences - Papers: Part A

The microstructure of Sn-8Zn-3Bi alloy was refined by increasing the solidification rate and the correlation between Zn-rich phase and the corrosion/oxidation behavior of the alloy was investigated. The Zn-rich phase transforms from coarse flakes to fine needles dispersed in the β-Sn matrix with the increase of the cooling rate. The transformation of Zn-rich precipitates enhances the anticorrosive ability of Sn-8Zn-3Bi alloy in 3.5 wt.% NaCl solution. On the contrary, Sn-8Zn-3Bi alloy with a fine needle-like Zn-rich phase shows poor oxidation resistance under air atmosphere, due to the fast diffusion of Zn atoms in Sn matrix.


Optimization Of A Ceiling Ventilation System With Integrated Photovoltaic Thermal Collectors And Phase Change Materials, Zhenjun Ma, Wenye Lin, Mohammed I. Sohel Jan 2016

Optimization Of A Ceiling Ventilation System With Integrated Photovoltaic Thermal Collectors And Phase Change Materials, Zhenjun Ma, Wenye Lin, Mohammed I. Sohel

Faculty of Engineering and Information Sciences - Papers: Part A

This paper presents the performance evaluation and design optimization of a ceiling ventilation system with integrated solar photovoltaic thermal (PVT) collectors and phase change materials (PCMs) by using a hybrid Particle Swarm Optimization and Hooke-Jeeves Pattern search (PSO-HJ) algorithm. In this novel ceiling ventilation system, the PVT collectors are used to generate electricity and provide the low-grade heating energy for buildings by using the winter daytime solar radiation, while the PCM is integrated into the building ceiling as part of the ceiling insulation and at the same time, as a centralized thermal energy storage unit to temporally store the low-grade …


Thermal Performance Evaluation And Optimal Design Of Buildings With Integrated Air-Based Photovoltaic Thermal Collectors And Phase Change Materials Using The Hooke-Jeeves Pattern Search Method, Wenye Lin, Zhenjun Ma, Paul Cooper Jan 2016

Thermal Performance Evaluation And Optimal Design Of Buildings With Integrated Air-Based Photovoltaic Thermal Collectors And Phase Change Materials Using The Hooke-Jeeves Pattern Search Method, Wenye Lin, Zhenjun Ma, Paul Cooper

Faculty of Engineering and Information Sciences - Papers: Part A

Over the last several decades, many low energy technologies have been developed and deployed to reduce building energy consumption. Among various solutions, solar photovoltaic thermal (PVT) collectors and phase change materials (PCMs) are among the most promising methods receiving increasing attention. This paper presents a thermal performance evaluation and optimal design of buildings integrated with air-based solar PVT collectors and PCMs embedded in the building envelope by using The Hooke-Jeeves pattern search method. The Hooke-Jeeves generalized pattern search is used to search for optimal solutions of the optimization problem. The variables optimized include the PVT air flow rate, additional wall …


Development Of A Novel Phase Change Material Emulsion For Cooling Systems, Jingjing Shao, Jo Darkwa, Georgios Kokogiannakis Jan 2016

Development Of A Novel Phase Change Material Emulsion For Cooling Systems, Jingjing Shao, Jo Darkwa, Georgios Kokogiannakis

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper, a novel phase change material emulsion (PCE-10) consisting of an organic PCM (RT10) and water has been developed. Its thermophysical properties such as heat of fusion, viscosity and sub-cooling temperature have been established. The chemical stability during both storage and discharge periods have also been evaluated. The results indicate low sub-cooling temperature and relatively long period of stability without any sign of segregation but the viscosity was found to be much higher than that of water.Further improvement and experimental studies into its flow characteristics are therefore being encouraged.


Novel Experimental Setup For Time-Of-Flight Mass Spectrometry Ion Detection In Collisions Of Anionic Species With Neutral Gas-Phase Molecular Targets, J C. Oller, L Ellis-Gibbings, F Ferreira Da Silva, Paulo Limao-Vieira, Gustavo Garcia Jan 2015

Novel Experimental Setup For Time-Of-Flight Mass Spectrometry Ion Detection In Collisions Of Anionic Species With Neutral Gas-Phase Molecular Targets, J C. Oller, L Ellis-Gibbings, F Ferreira Da Silva, Paulo Limao-Vieira, Gustavo Garcia

Faculty of Engineering and Information Sciences - Papers: Part A

We report a novel experimental setup for studying collision induced products resulting from the interaction of anionic beams with a neutral gas-phase molecular target. The precursor projectile was admitted into vacuum through a commercial pulsed valve, with the anionic beam produced in a hollow cathode discharge-induced plasma, and guided to the interaction region by a set of deflecting plates where it was made to interact with the target beam. Depending on the collision energy regime, negative and positive species can be formed in the collision region and ions were time-of-flight (TOF) mass-analysed. Here, we present data on O-2 precursor projectile, …


Using Solar Photovoltaic Thermal Collectors In Phase Change Materials Enhanced Buildings For Thermal Performance Management, Zhenjun Ma, Wenye Lin, Mohammed I. Sohel Jan 2015

Using Solar Photovoltaic Thermal Collectors In Phase Change Materials Enhanced Buildings For Thermal Performance Management, Zhenjun Ma, Wenye Lin, Mohammed I. Sohel

Faculty of Engineering and Information Sciences - Papers: Part A

This paper presents the investigation of using air-based solar photovoltaic thermal (PVT) collectors in phase change materials (PCMs) enhanced buildings for effective thermal management. PVT collectors are used to generate electricity and provide low grade heating energy to buildings for winter space heating. PCMs are either integrated into building walls to increase the local thermal mass or used as a temporary centralized thermal storage to store the low grade thermal energy derived from the PVT collectors. The thermal performance of buildings due to the integration of the PVT collectors and PCMs is tested and evaluated through computer simulations. It is …


Multiplicative Modelling Of Four-Phase Microbial Growth, María Jesús Munoz-Lopez, Maureen P. Edwards, Ulrike Schumann, Robert S. Anderssen Jan 2015

Multiplicative Modelling Of Four-Phase Microbial Growth, María Jesús Munoz-Lopez, Maureen P. Edwards, Ulrike Schumann, Robert S. Anderssen

Faculty of Engineering and Information Sciences - Papers: Part A

Microbial growth curves, recording the four-phases (lag, growth, stationary, decay) of the dynamics of the surviving microbes, are regularly used to support decision-making in a wide variety of health related activities including food safety and pharmaceutical manufacture. Often, the decision-making reduces to a simple comparison of some particular feature of the four-phases, such as the time at which the number of surviving microbes reaches a maximum. Consequently, in order to obtain accurate estimates of such features, the first step is the determination, from experimental measurements, of a quantitative characterization (model) of the four-phases of the growth-decay dynamics involved, which is …


Absolute Phase Recovery Of Three Fringe Patterns With Selected Spatial Frequencies, Yi Ding, Jiangtao Xi, Yanguang Yu, Fuqin Deng Jan 2015

Absolute Phase Recovery Of Three Fringe Patterns With Selected Spatial Frequencies, Yi Ding, Jiangtao Xi, Yanguang Yu, Fuqin Deng

Faculty of Engineering and Information Sciences - Papers: Part A

A new temporal approach is presented for the recovery of the absolute phase maps from their wrapped versions based on the use of fringe patterns of three different spatial frequencies. In contrast to the two-frequency method recently published, the method proposed is characterized by better anti-error capability as measured by phase error tolerance bound. A general rule for the selection of the three frequencies is presented, and its relationship to the phase error tolerance bound is derived. Theoretical analysis and experimental results are also presented to validate the effectiveness of the proposed three frequency technique.


An In-Situ Neutron Diffraction Study Of A Multi-Phase Transformation And Twinning-Induced Plasticity Steel During Cyclic Loading, Ahmed A. Saleh, Donald W. Brown, Elena V. Pereloma, Bjorn Clausen, Christopher H. J Davies, Carlos N. Tome, Azdiar A. Gazder Jan 2015

An In-Situ Neutron Diffraction Study Of A Multi-Phase Transformation And Twinning-Induced Plasticity Steel During Cyclic Loading, Ahmed A. Saleh, Donald W. Brown, Elena V. Pereloma, Bjorn Clausen, Christopher H. J Davies, Carlos N. Tome, Azdiar A. Gazder

Faculty of Engineering and Information Sciences - Papers: Part A

In-situ neutron diffraction during cyclic tension-compression loading (þ3.5% to 2.8%) of a 17Mn-3Al-2Si-1Ni-0.06C steel that exhibits concurrent transformation and twinning -induced plasticity effects indicated a significant contribution of intragranular back stresses to the observed Bauschinger effect. Rietveld analysis revealed a higher rate of martensitic transformation during tension compared to compression. Throughout cycling, a0-martensite exhibited the highest phase strains such that it bears an increasing portion of the macroscopic load as its weight fraction evolves. On the other hand, the e-martensite strain remained compressive as it accommodated most of the internal strains caused by the shape misfit associated with the c!e …


Modeling Minimum Transport Boundary For Fluidized Dense-Phase Pneumatic Conveying Systems, G Setia, Soumya Suddha Mallick, Renhu Pan, Peter W. Wypych Jan 2015

Modeling Minimum Transport Boundary For Fluidized Dense-Phase Pneumatic Conveying Systems, G Setia, Soumya Suddha Mallick, Renhu Pan, Peter W. Wypych

Faculty of Engineering and Information Sciences - Papers: Part A

For the reliable design of fluidized dense-phase pneumatic conveying systems, it is of paramount importance to accurately estimate blockage conditions or the minimum transport boundary. Existing empirical models for the fluidized dense-phase conveying of fine powders are either based on a limited number of products and pipelines or have not been tested for their accuracy and stability over a wide range of scale-up conditions. In this paper, based on the test results of 22 different powders conveyed through 38 pipelines, a unified model for the minimum transport boundary has been developed that represents gas Froude number as a function of …


Review Of Solid-Liquid Phase Change Materials And Their Encapsulation Technologies, Weiguang Su, Jo Darkwa, Georgios Kokogiannakis Jan 2015

Review Of Solid-Liquid Phase Change Materials And Their Encapsulation Technologies, Weiguang Su, Jo Darkwa, Georgios Kokogiannakis

Faculty of Engineering and Information Sciences - Papers: Part A

Various types of solid-liquid phase change materials (PCMs) have been reviewed for thermal energy storage applications. The review has shown that organic solid-liquid PCMs have much more advantages and capabilities than inorganic PCMs but do possess low thermal conductivity and density as well as being flammable. Inorganic PCMs possess higher heat storage capacities and conductivities, cheaper and readily available as well as being non-flammable, but do experience supercooling and phase segregation problems during phase change process. The review has also shown that eutectic PCMs have unique advantage since their melting points can be adjusted. In addition, they have relatively high …


Multi-Phase Variety Trials Using Both Composite And Individual Replicate Samples: A Model-Based Design Approach, Alison B. Smith, David G. Butler, C R. Cavanagh, Brian R. Cullis Jan 2015

Multi-Phase Variety Trials Using Both Composite And Individual Replicate Samples: A Model-Based Design Approach, Alison B. Smith, David G. Butler, C R. Cavanagh, Brian R. Cullis

Faculty of Engineering and Information Sciences - Papers: Part A

The present paper provides an approach for the design and analysis of variety trials that are used to obtain quality trait data. These trials are multi-phase in nature, comprising a field phase followed by one or more laboratory phases. Typically the laboratory phases are costly relative to the field phase and this imposes a limit on the number of samples that can be tested. Historically, this has been achieved by sacrificing field replication, either by testing a single replicate plot for each variety or a single composite sample, obtained by combining material from several field replicates. An efficient statistical analysis …


Phase Unwrapping Method Based On Multiple Fringe Patterns Without Use Of Equivalent Wavelengths, Limei Song, Yulan Chang, Jiangtao Xi, Qinghua Guo, Xin-Jun Zhu, Xiaojie Li Jan 2015

Phase Unwrapping Method Based On Multiple Fringe Patterns Without Use Of Equivalent Wavelengths, Limei Song, Yulan Chang, Jiangtao Xi, Qinghua Guo, Xin-Jun Zhu, Xiaojie Li

Faculty of Engineering and Information Sciences - Papers: Part A

In order to decrease the noise enhancement in the process of phase unwrapping, we present a new phase unwrapping approach for multiple wavelength phase shift profilometry. In this approach, a series of fringe images with only three wavelengths are captured by the 3D measurement system, and it does not need to calculate the equivalent wavelengths and the equivalent phases. As a result, the noise enhancement is avoided, leading to improved precision in the absolute phase map recovery. Experiment results demonstrate that the proposed method is more robust and effective compared to the existing TWPSP method.


Shadow Removal Method For Phase-Shifting Profilometry, Lei Lu, Jiangtao Xi, Yanguang Yu, Qinghua Guo, Yongkai Yin, Limei Song Jan 2015

Shadow Removal Method For Phase-Shifting Profilometry, Lei Lu, Jiangtao Xi, Yanguang Yu, Qinghua Guo, Yongkai Yin, Limei Song

Faculty of Engineering and Information Sciences - Papers: Part A

In a typical phase-shifting profilometry system for the three-dimensional (3D) shape measurement, shadows often exist in the captured images as the camera and projector probe the object from different directions. The shadow areas do not reflect the fringe patterns which will cause errors in the measurement results. This paper proposed a new method to remove the shadow areas from taking part in the 3D measurement. With the system calibrated and the object reconstructed, the 3D results are mapped on a point-by-point basis into the corresponding positions on the digital micro-mirror device (DMD) of the projector. A set of roles are …


Improving Fault Ride-Through Of Three Phase Voltage Source Inverter During Symmetrical Fault Using Dc Link Fault Current Limiter, Mehrdad Tarafdar Hagh, Amin Jalilian, Seyed Behzad Naderi, Michael Negnevitsky, Kashem M. Muttaqi Jan 2015

Improving Fault Ride-Through Of Three Phase Voltage Source Inverter During Symmetrical Fault Using Dc Link Fault Current Limiter, Mehrdad Tarafdar Hagh, Amin Jalilian, Seyed Behzad Naderi, Michael Negnevitsky, Kashem M. Muttaqi

Faculty of Engineering and Information Sciences - Papers: Part A

The majority of distributed generation (DG) units utilize three phase voltage source inverter (VSI) to exchange electric power with the utility grid. The VSI employs semiconductor devices (SDs) with limited current withstand capabilities which are very vulnerable during grid faults. However, to ensure a secure and reliable operation of power systems at high penetration level of the DGs, most of the new grid codes worldwide require that the VSIs must have fault ride-Through (FRT) capability. This paper presents a DC link fault current limiter (DLFCL) based VSI FRT scheme to improve its FRT capability. In the proposed scheme, the DLFCL …


Development Of High Melting Temperature Microencapsulated Phase Change Material For Compacted Thermal Energy Storage Bed, Weiguang Su, Jo Darkwa, Georgios Kokogiannakis Jan 2014

Development Of High Melting Temperature Microencapsulated Phase Change Material For Compacted Thermal Energy Storage Bed, Weiguang Su, Jo Darkwa, Georgios Kokogiannakis

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper a novel high temperature microencapsulated phase change material (MEPCM) based on paraffin as the core material and MF resin as the shell material has been developed with the in-situ polymerization method for solar hot water storage application. The results showed that the type of emulsifier could influence core material content, the encapsulation efficiency as well as the latent heat capacity. Based on the results and analysis the study has shown that energy storage density could be increased by as much as 59% if 60wt% of MEPCM 1 was to be used in the proposed compacted MEPCM-water bed …


Multi-Phase Ant Colony System For Multi-Party Data-Intensive Service Provision, Lijuan Wang, Jun Shen Jan 2014

Multi-Phase Ant Colony System For Multi-Party Data-Intensive Service Provision, Lijuan Wang, Jun Shen

Faculty of Engineering and Information Sciences - Papers: Part A

The rapid proliferation of enormous sources of digital data has led to greater dependence on data-intensive services. Each service may actually request or create a large amount of data sets. To compose these services will be more challenging. Issues such as autonomy, scalability, adaptability, and robustness, become difficult to resolve. In order to automate the process of reaching an agreement among service composers, service providers, and data providers, an ant-inspired negotiation mechanism is considered in this paper. We exploit a group of agents automatically negotiating to establish agreeable service contracts. Twostage negotiation procedures are used in our data-intensive service provision …