Engineering Commons^™

Particle Size-Dependent Microstructure, Hardness And Electrochemical Corrosion Behavior Of Atmospheric Plasma Sprayed Nicrbsi Coatings, Peng Sang, Liang-Yu Chen, Cuihua Zhao, Ze-Xin Wang, Haiyang Wang, Sheng Lu, Dongpo Song, Jia-Huan Xu, Lai-Chang Zhang

Research outputs 2014 to 2021

Particle size is a critical consideration for many powder coating-related industries since it significantly influences the properties of the produced materials. However, the effect of particle size on the characteristics of plasma sprayed NiCrBSi coatings is not well understood. This work investigates the microstructures, hardness and electrochemical corrosion behavior of plasma sprayed NiCrBSi coatings synthesized using different-sized powders. All coatings mainly consist of Ni, N3B, CrB, Cr7C3 and Cr3C2 phases. The coatings produced by small particles (50–75 μm) exhibit lower porosity (2.0 ± 0.8%). Such coatings show a higher fraction (15.5 vol.%) of the amorphous phase and lower hardness (700 …

A Statistical Approach To Provide Explainable Convolutional Neural Network Parameter Optimization, Saman Akbarzadeh, Selam Ahderom, Kamal Alameh

Research outputs 2014 to 2021

Algorithms based on convolutional neural networks (CNNs) have been great attention in image processing due to their ability to find patterns and recognize objects in a wide range of scientific and industrial applications. Finding the best network and optimizing its hyperparameters for a specific application are central challenges for CNNs. Most state-of-the-art CNNs are manually designed, while techniques for automatically finding the best architecture and hyperparameters are computationally intensive, and hence, there is a need to severely limit their search space. This paper proposes a fast statistical method for CNN parameter optimization, which can be applied in many CNN applications …

Board 141: Engineering Identity As A Predictor Of Undergraduate Students' Persistence In Engineering, Debra A. Major, Seterra D. Burleson, Xiaoxiao Hu, Kristi J. Shryock

Psychology Faculty Publications

Improving graduation rates of students who have selected and been admitted to engineering majors is a pivotal strategy in supporting national initiatives to increase the number of engineering graduates. Research suggests that the degree to which a student is attached to or belongs to engineering as a discipline better explains persistence-related outcomes than lack of interest and ability. As a result, identity frameworks have proven useful for furthering the understanding of engineering persistence. In this paper, we examine the relationship between undergraduate students’ engineering identity and persistence as an engineering major.

As part of an ongoing NSF IUSE project, a …

A Novel Solar-Driven Direct Contact Membrane-Based Water Desalination System, Abdellah Sharifian, Mehdi Khiadani

Research outputs 2014 to 2021

This study proposes a novel integrated solar membrane-based desalination system. The system includes vacuum glass tubes to increase absorbed solar energy and to decrease heat loss, heat pipes to transfer the absorbed energy efficiently, and a tubular direct contact membrane distillation module to use the absorbed energy more effectively. To improve the freshwater production rate and overall efficiency of the proposed system, a cooling unit was also added to the permeate loop of the desalination unit. The performance of the system was experimentally investigated without (Case I) and with (Case II) the cooling unit in summer and without the cooling …

Effect Of Al Alloying On Cavitation Erosion Behavior Of Tasi2 Nanocrystalline Coatings, Jiang Xu, Shuai Kang Zhang, Xiao Lin Lu, Shuyun Jiang, Paul Munroe, Zong-Han Xie

Research outputs 2014 to 2021

To broaden the scope of non-aerospace applications for titanium-based alloys, both hexagonal C40 binary TaSi₂ and ternary Al alloyed TaSi₂ nanocrystalline coatings were exploited to enhance the cavitation erosion resistance of Ti-6Al-4V alloy in acidic environments. To begin with, the roles of Al addition in influencing the structural stability and mechanical properties of hexagonal C40 Ta(Si_1-xAl_x)₂ compounds were modelled using first-principles calculations. The calculated key parameters, such as Pugh's index (B/G ratio), Poisson's ratio, and Cauchy pressures, indicated that there was a threshold value for Al addition, below which the increase of Al …

Co 2 -Wettability Of Sandstones Exposed To Traces Of Organic Acids: Implications For Co 2 Geo-Storage, Muhammad Ali, Muhammad Arif, Muhammad Faraz Sahito, Sarmad Al-Anssari, Alireza Keshavarz, Ahmed Barifcani, Linda Stalker, Mohammad Sarmadivaleh, Stefan Iglauer

Research outputs 2014 to 2021

Wettability of CO 2 -brine-mineral systems plays a vital role during geological CO 2 -storage. Residual trapping is lower in deep saline aquifers where the CO 2 is migrating through quartz rich reservoirs but CO 2 accumulation within a three-way structural closure would have a high storage volume due to higher CO 2 saturation in hydrophobic quartz rich reservoir rock. However, such wettability is only poorly understood at realistic subsurface conditions, which are anoxic or reducing. As a consequence of the reducing environment, the geological formations (i.e. deep saline aquifers) contain appreciable concentrations of various organic acids. We thus demonstrate …

An Experimental Study On The Flow Characteristics During The Leakage Of High Pressure Co 2 Pipelines, Shuaiwei Gu, Yuxing Li, Lin Teng, Cailin Wang, Qihui Hu, Datong Zhang, Xiao Ye, Jinghan Wang, Stefan Iglauer

Research outputs 2014 to 2021

High pressure pipeline transportation is dominant mode for economically transporting large amounts of CO 2 . However, potential leakage is one of the main risks associated with pressurized CO 2 pipeline transportation. Thus, to investigate the leakage behavior of high pressure CO 2 and to de-risk such transportations, a new laboratory scale experimental setup (total length of 14.85 m and the inner diameter of 15 mm) was constructed. Leakage experiments for pure CO 2 and CO 2 mixtures containing various N 2 concentrations were carried out for different initial phase states (supercritical, liquid and gaseous respectively). The pressure and temperature …

Strategies To Improve The Thermal Performance Of Heat Pipe Solar Collectors In Solar Systems: A Review, Abdellah Sharifian, Mehdi Khiadani, Ataollah Nosrati

Research outputs 2014 to 2021

Invention of evacuated tube heat pipe solar collectors (HPSCs) was a huge step forward towards resolving the challenges of conventional solar systems due to their unique features and advantages. This has led to their utilization in a wide range of solar applications surpassing other conventional collectors. However, relatively low thermal efficiency of heat pipe solar (HPS) systems is still the major challenge of solar industry evidenced by numerous studies conducted mainly during the last decade to improve their efficiency. To date, several review papers have been published summarizing studies relevant to utilization of HPSCs in various thermal applications. However, to …

Calculation Of Critical Water Flow Rates For Wildfire Suppression, Greg Penney, Daryoush Habibi, Marcus Cattani, Murray Carter

Research outputs 2014 to 2021

Predicting water suppression requirements and its impacts on firefighting strategies and logistics within the urban environment has been the subject of many previous studies, however the same level of research has yet to be applied in the realm of wildfire suppression. To work towards addressing this knowledge gap, this paper provides guidance for Incident Controllers in relation to critical water flow rates required to extinguish large wildfire across a wide range of forest fuel loads, fire weather and active fire front depths. This is achieved through mathematical empirical analysis of water flow rates required for head fire suppression during 540 …

Effective Plant Discrimination Based On The Combination Of Local Binary Pattern Operators And Multiclass Support Vector Machine Methods, Vi N T Le, Beniamin Apopei, Kamal Alameh

Research outputs 2014 to 2021

Accurate crop and weed discrimination plays a critical role in addressing the challenges of weed management in agriculture. The use of herbicides is currently the most common approach to weed control. However, herbicide resistant plants have long been recognised as a major concern due to the excessive use of herbicides. Effective weed detection techniques can reduce the cost of weed management and improve crop quality and yield. A computationally efficient and robust plant classification algorithm is developed and applied to the classification of three crops: Brassica napus (canola), Zea mays (maize/corn), and radish. The developed algorithm is based on the …

Taylor's Slope Stability Chart For Combined Effects Of Horizontal And Vertical Seismic Coefficients, Pragyan Sahoo, Sanjay Kumar Shukla

Research outputs 2014 to 2021

Design standards and codes of practice on earth slope stability often recommend the pseudo-static method of analysis for determining the factor of safety of a slope subjected to seismic forces. In most pseudo-static methods of analysis, the horizontal seismic force is considered without due weightage to vertical seismic force. In the past, Taylor's stability chart for a homogeneous cohesive-frictional soil slope has been extended to consider the effect of horizontal seismic force only. In this paper, an attempt is made to develop an analytical formulation considering both horizontal and vertical seismic forces in order to estimate the factor of safety …

Deformation And Strength Characteristics Of Laves Phases In Titanium Alloys, Chirag D. Rabadia, Y. J. Liu, Liang-Yu Chen, Syed F. Jawed, L. Q. Wang, Hongqi Sun, Laichang Zhang

Research outputs 2014 to 2021

The superior reinforcement nature of Laves phases make them suitable for high-strength applications. Therefore, investigations on the deformation and strength characteristics of Laves phases are useful in development of an improved Laves phase-reinforced alloy. In this work, the Vickers micro-indentation method is used to evaluate and compare the deformation and strength characteristics of a hexagonal close-packed Laves phase (C14-type) in Ti-35Zr-5Fe-6Mn (wt%) and a face-centered cubic Laves phase (C15-type) in Ti-33Zr-7Fe-4Cr (wt%), considering the same volume fraction of Laves phase (~7.0%) in these alloys. Moreover, the effects of higher volume fraction of Laves phase (19.4%) on indentation-based deformation features are …

Real-Time Classification Of Multivariate Olfaction Data Using Spiking Neural Networks, Arnup Vanarse, Adam Osseiran, Alexander Rassau, Therese O'Sullivan, Jonny Lo, Amanda Devine

Research outputs 2014 to 2021

Recent studies in bioinspired artificial olfaction, especially those detailing the application of spike-based neuromorphic methods, have led to promising developments towards overcoming the limitations of traditional approaches, such as complexity in handling multivariate data, computational and power requirements, poor accuracy, and substantial delay for processing and classification of odors. Rank-order-based olfactory systems provide an interesting approach for detection of target gases by encoding multi-variate data generated by artificial olfactory systems into temporal signatures. However, the utilization of traditional pattern-matching methods and unpredictable shuffling of spikes in the rank-order impedes the performance of the system. In this paper, we present an …

Thermal Performance Of An Evacuated Tube Heat Pipe Solar Water Heating System In Cold Season, Abdellah Sharifian, Mehdi Khiadani, Ataollah Nosrati

Research outputs 2014 to 2021

This study evaluates the performance of a heat pipe solar water heating system to meet a real residential hot water consumption pattern theoretically and experimentally under non-ideal climatic conditions during a cold day in Perth, Western Australia. A mathematical model was developed and used to calculate the optimum number of glass tubes of the heat pipe solar collector. Based on the obtained data, an experimental rig with 25 glass tubes was designed, built, and tested as the temperature changes after 25 tubes reached the insignificant value of 0.6%. The results showed that hot water extraction had significant impact on the …

Phase Interaction Induced Texture In A Plasma Sprayed-Remelted Nicrbsi Coating During Solidification: An Electron Backscatter Diffraction Study, Liang-Yu Chen, Tianxiang Xu, Haiyang Wang, Peng Sang, Sheng Lu, Ze-Xin Wang, Shujin Chen, Lai-Chang Zhang

Research outputs 2014 to 2021

Although considerable endeavors have been dedicated to investigate the microstructures of the remelting-enhanced NiCrBSi coatings, the textures in the remelted coatings, which may result in property anisotropy, are rarely studied. In this work, the recrystallized fractions, grain orientations and interphase boundaries for Ni, Ni₃B and CrB in a plasma sprayed-remelted NiCrBSi coating were investigated by electron backscatter diffraction. The results demonstrate that the texture is induced by phase interaction during solidification. Cooling from the liquid, the firstly formed Ni grains possess a cube fiber texture of {001}〈001〉. The successively formed Ni₃B colonies are randomly oriented and …

Degradation And Hydrate Phase Equilibria Measurement Methods Of Monoethylene Glycol, Khalid Alef, Stefan Iglauer, Ahmed Barifcani

Research outputs 2014 to 2021

Monoethylene glycol (MEG), a common chemical used for the inhibition of gas hydrate formation may undergo degradation in the regeneration/reclamation process. Limited research exists on the effect of degradation of MEG on hydrate formation, production facilities and equipment especially in the presence of other chemical additives. The proposed method allows for streamlining the process of preparing, degrading and analysis of MEG solutions for hydrate testing and degradation products.

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Procedure to prepare accurate MEG solutions avoiding oxidative degradation of MEG (i.e., controlling oxygen ingress).

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Two methods are suggested to mimic field-like degradation of MEG solutions (i.e., degradation by reclamation …

Effect Of Direct Current Electric Field Intensity And Electrolyte Layer Thickness On Oxygen Reduction In Simulated Atmospheric Environment, Xin Zhang, Junxi Zhang, Qimeng Chen, Nianwei Dai, Qingzhao Ni, Lai-Chang Zhang, Fahe Cao, Jianqing Zhang

Research outputs 2014 to 2021

The effect of direct current (DC) electric field and electrolyte layer thickness on oxygen reduction in simulated atmospheric environment were investigated using electrochemical measurements. The results show that the limiting diffusion current density (i_lim) decreases with increasing the thin electrolyte layers (TELs) thickness but it increases with increasing the DC electric field intensity. The potential shifts negatively with the DC electric field. It is found that the DC electric field enables OH⁻ ions to quickly migrate from the solution/electrode interface to the electrolyte layer. All these features promote the cathodic reduction process thereby enhancing the metal …

Chemically Dealloyed Fe-Based Metallic Glass With Void Channels-Like Architecture For Highly Enhanced Peroxymonosulfate Activation In Catalysis, J.C. Wang, S.X. Liang, Z. Jia, W.C. Zhang, W.M. Wang, Y.J. Lui, J. Lu, L.C Zhang

Research outputs 2014 to 2021

Metallic glasses (MGs) with their intrinsic disordered atomic structure and widely controllable atomic components have recently emerged as fascinating functional materials in wastewater treatment. Compared to crystalline alloys, the less-noble atomic components in monolithic metallic glass are more efficient to be selectively dissolved during dealloying process. This work reported a facile chemical dealloying approach to fabricate a void channels-like structured MG with the elemental components of Fe73.5Si13.5B9Cu1Nb3 for methylene blue (MB) degradation. Results indicated that the dealloyed Fe73.5Si13.5B9Cu1Nb3 MGs with the void channels-like morphology presented a significant improvement of catalytic efficiency and reusability. The dye degradation reaction rate (kobs) of …

Noninvasive Diagnosis Of Irritable Bowel Syndrome Via Bowel Sound Features: Proof Of Concept, Xuhao Du, Gary Allwood, K. Mary Webberley, Andrisha-Jade Inderjeeth, Adam Osseiran, Barry James Marshall

Research outputs 2014 to 2021

INTRODUCTION: Irritable bowel syndrome (IBS) is a common and debilitating disorder estimated to affect approximately 11% of the world's population. Typically, IBS is a diagnosis of exclusion after patients undergo a costly and invasive colonoscopy to exclude organic disease. Clinician's and researchers have identified a need for a new cost-effective, accurate, and noninvasive diagnostic test for IBS.

METHODS: Using a diagnostic case-control study, we explored the use of bowel sounds to characterize IBS with a view to diagnostic use. We recruited participants with an existing clinical diagnosis of IBS or healthy (asymptomatic) digestive systems. We recorded bowel sounds for 2 …

Assesment Of Electricity Excess In An Isolated Hybrid Energy System: A Case Study Of A Dangiwada Village In Rural Nepal, Ashish Shrestha, Lalit Bickram Rana, Ajay Singh, Sudip Phuyal, Anil Ghimire, Roshan Giri, Roshan Kattel, Kedar Karki, Shailendra Kumar Jha

Research outputs 2014 to 2021

The increasing demand of power can be fulfilled through different architectures and electricity supply models by utilizing the available local resources. But most of the isolated energy system suffers from high energy cost and unreliable energy supply. This study identifies different electricity supply models to fulfill the dynamic demand of power in a remote area, which is analyzed in terms of cost of energy and causes for the high cost of energy. Among different factors, the presence of unusable energy (Electricity Excess) produced by the energy system during fulfillment of the demand is found to be major one cause for …

Natural Source Zone Depletion Of Lnapl: A Critical Review Supporting Modelling Approaches, Kaveh Sookhak Lari, Greg B. Davis, John L. Rayner, Trevor P. Bastow, Geoffrey J. Puzon

Research outputs 2014 to 2021

Natural source zone depletion (NSZD) of light non-aqueous phase liquids (LNAPLs) includes partitioning, transport and degradation of LNAPL components. NSZD is being considered as a site closure option during later stages of active remediation of LNAPL contaminated sites, and where LNAPL mass removal is limiting. To ensure NSZD meets compliance criteria and to design enhanced NSZD actions if required, residual risks posed by LNAPL and its long term behaviour require estimation. Prediction of long-term NSZD trends requires linking physicochemical partitioning and transport processes with bioprocesses at multiple scales within a modelling framework. Here we expand and build on the knowledge …

Recent Developments In Solar Energy-Harvesting Technologies For Building Integration And Distributed Energy Generation, Mikhail Vasiliev, Mohammad Nur-E-Alam, Kamal Alameh

Research outputs 2014 to 2021

We present a review of the current state of the field for a rapidly evolving group of technologies related to solar energy harvesting in built environments. In particular, we focus on recent achievements in enabling the widespread distributed generation of electric energy assisted by energy capture in semi-transparent or even optically clear glazing systems and building wall areas. Whilst concentrating on recent cutting-edge results achieved in the integration of traditional photovoltaic device types into novel concentrator-type windows and glazings, we compare the main performance characteristics reported with these using more conventional (opaque or semi-transparent) solar cell technologies. A critical overview …

Enhancing Heat Pipe Solar Water Heating Systems Performance Using A Novel Variable Mass Flow Rate Technique And Different Solar Working Fluids, Abdellah Shafieian, Junaid Jaffer Osman, Mehdi Khiadani, Ataollah Nosrati

Research outputs 2014 to 2021

This paper aims to improve the overall efficiency of heat pipe solar water heating (HPSWH) systems by implementing a novel variable mass flow rate technique which regulates the solar working fluid mass flow rate of the system with the solar radiation intensity. To analyse the system under real operational conditions, the residential hot water consumption pattern of Perth residents in Western Australia was used in the experiments. In addition, a nanofluid (Al₂O₃/DI) was fabricated and its performance as the solar working fluid was investigated to find the optimum concentration and to confirm its stability and thermo-physical …

Performance Analysis Of A Thermal-Driven Tubular Direct Contact Membrane Distillation System, Abdellah Sharifian, Mehdi Khiadani, Ataollah Nosrati

Research outputs 2014 to 2021

This paper examines the performance of a thermal-driven tubular direct contact membrane distillation (DCMD) system theoretically and experimentally. A multi-step mathematical model was developed to predict the freshwater productivity of the tubular DCMD module applicable for both small and large-scale applications by considering the changes in the operational variables along the membrane’s length. The proposed model was verified by building an experimental rig which was tested under different operational conditions. The results showed that keeping the mass flow rates in the hot and cold channels either near the end or beyond the transition range of the flows results in higher …

Design And Synthesis Of A New Mannitol Stearate Ester-Based Aluminum Alkoxide As A Novel Tri-Functional Additive For Poly(Vinyl Chloride) And Its Synergistic Effect With Zinc Stearate, Wenyuan Han, Manqi Zhang, Degang Li, Tianbao Dong, Bing Ai, Jianping Dou, Hongqi Sun

Research outputs 2014 to 2021

Thermal stabilizers, lubricant, and plasticizers are three crucial additives for processing poly(vinyl chloride) (PVC). In this study, a new mannitol stearate ester-based aluminum alkoxide (MSE-Al) was designed and synthesized as a novel additive for PVC. The thermal stability and processing performance of PVC stabilized by MSE-Al were evaluated by the Congo red test, conductivity measurement, thermal aging test, ultravioletevisible (UV–Vis) spectroscopy test, and torque rheometer test. Results showed that the addition of MSE-Al could not only markedly improve the long-term thermal stability of PVC, but also greatly accelerate the plasticizing and decrease the balance torque, which demonstrated that MSE-Al possessed …

Optimization Of Well Pad Design And Drilling - Well Clustering, Aleksandr Abramov

Research outputs 2014 to 2021

A model accounting for more than 30 parameters of drilling projects, and a computer program to enumerate groupings of the wells of a pad with consequent calculations of technical-economic characteristics, are developed and tested. Seven drilling scenarios for a 24-well pad with different starting oil flow rates for the wells are studied. Optimal well groupings in terms of Net Present Value (NPV) for three discount rates and five oil production decline rates have been found. The results show that: NPV-maximizing well pad designs with unequal (varying) numbers of wells in groups (clusters) may require only slight alterations …

Facile Synthesis Of Di-Mannitol Adipate Ester-Based Zinc Metal Alkoxide As A Bi-Functional Additive For Poly(Vinyl Chloride), Yuepeng Li, Degang Li, Wenyuan Han, Manqi Zhang, Bing Ai, Lipeng Zhang, Hongqi Sun, Zhen Cui

Research outputs 2014 to 2021

A new di-mannitol adipate ester-based zinc metal alkoxide (DMAE-Zn) was synthesized as a bi-functional poly(vinyl chloride) (PVC) thermal stabilizer for the first time. The materials were characterized with Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA). Characterization results confirmed the formation of Zn–O bonds in DMAE-Zn, and confirmed that DMAE-Zn had a high decomposition temperature and a low melting point. The thermal stability of DMAE-Zn on PVC also was tested by a conductivity test, a thermal aging test, and a UV-visible spectroscopy (UV-VIS) test. PVC stabilized by DMAE-Zn had a good initial color and excellent long-term stability. UV-VIS also …

Phase Separation And Enhanced Wear Resistance Of Cu88fe12 Immiscible Coating Prepared By Laser Cladding, Shuzhen Zhao, Shengfeng Zhou, Min Xie, Xiaoqin Dai, Dongchu Chen, Laichang Zhang

Research outputs 2014 to 2021

In order to eliminate the microstructure segregation of Cu–Fe immiscible alloys which characterized with a liquid miscible gap, the Cu88Fe12 (wt.%) immiscible coating was prepared by laser cladding. The phase separation characteristic and wear resistance of the Cu88Fe12 (wt.%) immiscible coating were also investigated. The results show that the size of the milled Cu88Fe12 composite powder is reduced comparing to that of the un-milled powder due to fracturing during mechanical milling. Moreover, the demixing or delamination disappears in the Cu88Fe12 immiscible coating and a large amount of face-centered-cubic (fcc) γ-Fe and body-centered-cubic (bcc) α-Fe particles are dispersed in the face-centered-cubic …

Nanoindentation Characterization On Local Plastic Response Of Ti-6al-4v Under High-Load Spherical Indentation, Yan Wen, Lechun Xie, Zhou Wang, Liqiang Wang, Weijie Lu, Laichang Zhang

Research outputs 2014 to 2021

After high-load spherical indentation treatment, the variations of hardness on the plastic zone of Ti-6Al-4V were investigated via nanoindentation method. The hardness within the center of plastic zone was measured by nanoindenter, and the magnitude decreased gradually along the depth, which were caused by the different extent of plastic deformation under the residual imprint. The microstructure of indentation were observed using scanning electron microscope (SEM) before and after surface etching, and the results showed that the microhardness revealed the average hardness of α and β phases of Ti-6Al-4V. The maximum hardness reached 6.438 GPa in the depth of 132 μm. …

Fire Performance Of Heavyweight Self-Compacting Concrete And Heavyweight High Strength Concrete, Farhad Aslani, Fatemeh Hamidi, Qilong Ma

Research outputs 2014 to 2021

In this study, the fresh and hardened state properties of heavyweight self-compacting concrete (HWSCC) and heavyweight high strength concrete (HWHSC) containing heavyweight magnetite aggregate with 50, 75, and 100% replacement ratio, and their performance at elevated temperatures were explored experimentally. For fresh-state properties, the flowability and passing ability of HWSCCs were assessed by using slump flow, T500 mm, and J-ring tests. Hardened-state properties including hardened density, compressive strength, and modulus of elasticity were evaluated after 28 days of mixing. High-temperature tests were also performed to study the mass loss, spalling of HWSCC and HWHSC, and residual mechanical properties at 100, …