CSME Conference Proceedings (May 27-30, 2018)

Permanent URI for this collection

https://hdl.handle.net/10315/35192

Browse

Now showing 1 - 20 of 216

Open Access
Modeling Viscoelastomers With Nonlinear Viscosity
(CSME-SCGM, Jun-18) Zhou, Jianyou; Jiang, Liying; Khayat, Roger
Consisting of highly mobile and flexible polymer chains, elastomers are known to exhibit viscoelastic behavior. Adopting concepts from the theory of polymer dynamics and finite-deformation viscoelasticity, this work presents a micromacro constitutive model to investigate the viscoelastic behavior of elastomers, in which the material viscosity varies with the macroscopic deformation. The developed model is then applied to study the stress response of elastomers. From the simulation results, it is observed that the developed model exhibits strong capability of capturing the typical response behaviors of elastomers (e.g., strain-softening behavior). A comparison of the stress responses between linear and nonlinear viscosity is also considered in this work. The modeling framework in this paper is expected to provide a general approach and a platform to analyze the viscoelastic behavior of rubber-like materials with nonlinear viscosity.
Open Access
Energy Benefits Of Integrating Transportation Energy With A Net Zero Energy Solar Building Using Captured Waste Hydrogen From Electrochemical Plants And Bio-Gas From Various Bio-Gasification Processes
(CSME-SCGM, May-18) Garmsiri, Shahryar; Rosen, Marc A.
When considering a net zero energy building, the transportation energy sector is often viewed as a separate entity. Currently, hydrocarbons are the main source of energy used in the transportation sector. In an effort to reduce greenhouse gas emissions, more automotive manufacturers are moving towards alternatively fueled vehicles that are electric or fuel cell powered. Electrochemical and other process industries frequently vent or flare hydrogen into the atmosphere and most community municipal waste is buried underground (landfill) or burned to generate electricity resulting in greenhouse gas emissions. Energy benefits and the methods of achieving net zero energy status for a solar building and reduction of greenhouse gas emissions through the integration of these waste streams and transportation energy are discussed.
Open Access
New Experimental Setup Design For Applying Physical Blowing Agent In Rapid Rotational Foam Molding Technology
(CSME-SCGM, May-18) Raktim, Isha; Pop-Iliev, Remon
This paper presents a manufacturing process for extrusion assisted foam production with a physical blowing agent (PBA) for Rapid Rotational Foam Molding. A completely new experimental setup was designed to identify, conceive, establish, and develop, the necessary processing concepts and conditions for fabricating a new class of rotationally molded integral-skin cellular composite having low-density foamed core. The new design incorporates a helical static mixer that can operate at 31 MPa in 200°C environment. Supercritical CO2 will be injected into the pressurized static mixer to thoroughly disassociate into the polymer melt to create a single-phase solution. The process temperature is maintained by PID controlled band heaters and an integral liquid cooling jacket. The system can facilitate rapid pressure drop as high as 30 MPa to produce polyolefin foam.
Open Access
Evaluation Of Energy Efficient Propulsion Technologies For Unmanned Aerial Vehicles
(CSME-SCGM, May-18) Matlock, Jay; Sharikov, Philipp; Warwick, Stephen; Richards, Jenner; Suleman, Afzal
The transition to cleaner, more efficient and longer-endurance aircraft is at the forefront of current research and development in air transportation systems. The focus of this research is to experimentally evaluate Hybrid Propulsion and Energy Harvesting Systems in Unmanned Aerial Vehicles (UAV). Hybrid systems offer several potential benefits over more conventional gasoline and electric systems including lower environmental impacts, reduced fuel consumption, longer endurance, redundancy and distributed propulsion. Additional energy efficiency can be achieved by harvesting some of the thermal energy of the exhaust gases. By using the Seebeck effect, the temperature gradient between ambient air and the exhaust can be used to generate electric power, making it possible to eliminate costly mechanical systems such as alternators and reduce fuel consumption. The development and experimental evaluation of a hybrid-propulsion UAV was carried out at the University of Victoria Center for Aerospace Research (UVIC-CfAR) in the framework of the Green Aviation Research & Development Network (GARDN) grant. The work involved the development of a framework to evaluate UAV hybrid propulsion efficiency, as well as to predict the amount of power harvestable from thermoelectric generators (TEG). The hybrid propulsion framework was used to investigate the trade-offs between different hybrid architectures against conventional electric and internal combustion propulsion systems. The energy harvesting module was designed to evaluate the trade-off between energy harvested, implementation costs and weight. In order to validate the computational results, experimental testing was performed. First, an apparatus was designed to collect performance data of a triple-TEG system connected to a 4-stroke Saito internal combustion engine. Thermal performance of the system was evaluated at eleven different test points, and a number of variables were modified to simulate real flight profiles. Next, another apparatus was designed to characterize the performance of a parallel hybrid-electric propulsion system in a UAV. This apparatus allows for different mission profiles that closely match the flight test data from other propulsion types.
Open Access
Meso-Scale Computational Modeling Of Hypervelocity Impact Damage In Advanced Materials
(CSME-SCGM, May-18) Cherniaev, Aleksandr; Telichev, Igor
Modeling of hypervelocity impact (HVI) on materials and structures is often associated with high computational expenses, especially when inhomogeneous materials are involved. To reduce computational cost, complex materials are often represented in modeling as homogeneous substances with the effective properties similar to those of the real materials. Although this approach has been successfully used in modeling of HVI on different materials with complex architecture, there are applications where it may not be applicable due to significant influence of materials’ mesoscale features on resulting HVI damage. Two of such applications are considered in this study, and include simulation of HVI on sandwich panels with metallic foamcores, and composites fabricated by filament winding. In the former case, adequate modeling of the multi-shock action of the foam ligaments on hypervelocity fragment cloud propagating through the foam core requires an explicit representation of the foam geometry in numerical model. In the latter case, the meso-scale modeling is required due to experimentally observed dependence of HVI damage of the composite on the particular filament winding pattern used in its fabrication. The study presents numerical models developed for both of these applications and compares numerical results with obtained experimental data.
Open Access
Preparation and Properties of Nanoparticle-enhanced Composite Phase Change Material with Ceramic Porous Media
(CSME-SCGM, May-18) Li, Runfeng; Zhou, Yang; Duan, Xili
Nanoparticle-enhanced tailing-paraffin composite phase change material (NCPCM) is fabricated by spontaneous melt infiltration. Industrial waste-iron tailing is used as raw material to prepare ceramic porous carrier with a foam-gel casting method. By adjusting the fabrication parameters, optimal NCPCM properties are obtained with paraffin content of 70%~88% and thermal conductivity of 0.351~0.490 W/(m·K), which is nearly 200% the thermal conductivity of paraffin wax. After 25 melting/solidification cycles, the nanoparticles remain well dispersion with overall stability in the composite phase change material, and the thermal conductivity slightly decreased from 0.349 to 0.317 W/ m·K. With multiple melting and solidification cycles, a low weight loss of 2.3~7.8 wt.% is demonstrated. The strength of ceramic frame is found to have a direct effect on the weight loss. Compared with exisiting nanoparticle-enhanced phase change material, the new NCPCM shows significantly improved thermal conductivity and better nanoparticle stability due to its ability to prevent nanoparticles from disposition.
Open Access
Vortex-Induced Vibrations Of A Low-Tension Cable-Sheave System Modeled Using Nonlinear Finite Elements
(CSME-SCGM, May-18) Westin, Cassidy; Irani, Rishad A.
This work presents a finite element model of a cablesheave system constructed to model cable vibrations due to vortex shedding in low-tension cases. The study assesses the potential for vortex shedding to lead to detachment of the cable from the sheave. The absolute nodal coordinate formulation is utilized to define the cable structural dynamics. Vortex shedding forces are incorporated by coupling the cable’s equations of motion to a Van der Pol equation, also known as a wakeoscillator and the cable-sheave interaction is described using a contact penalty method. The study examines the contribution of vortex shedding occurring at the cable’s natural frequency to the cable motion. For the cases studied the model demonstrates that vortex shedding alone results in very small vibration amplitudes and thus is unlikely to result in cable detachment.
Open Access
Adaptive Yaw Control Of Three-Axle Road Vehicles Based On Mass, Yaw Inertia And Cg Position Identification
(CSME-SCGM, May-18) Zhang, Yubiao; Woo, Ami; Khajepour, Amir
This paper introduces an adaptive yaw control scheme based on the estimation of the vehicle mass, yaw inertia and center of gravity (CG) position. The control deigns for three-axle road vehicles, which can be trucks, buses, or even three-axle passenger cars. System parameters of these vehicles vary significantly due to varying conditions, such as unloading and fully-loading of payloads. As a result, control references and fixed-model-based controller lose efficacy. The proposed adaptive yaw control compensates these issues, utilizing the integration of a least-square based parameter identification algorithm and a Model Reference Adaptive Control (MRAC) law. Simulation test results verify the effectiveness of the proposed adaptive control scheme.
Open Access
Effect of Dispersing Copper Oxide Nanoparticles to RT-35 filled a Circular Thermal Energy Storage System
(CSME-SCGM, May-18) Ebadi, Soroush; Hajiyan, Mohammadhossein; Tasnim, Syeda; Aliabadi, Amir Abbas; Mahmud, Shohel
Phase Change Materials (PCMs) have been widely used in Latent Heat Thermal Energy Storage Systems (LHTES) to store and release thermal energy. However, PCMs suffer from their low thermal conductivities, which leads to longer melting (charging) or solidification (discharging) time. Dispersing highly conductive nanoparticles into PCM is one of the methods to improve the thermal conductivity of the PCM. In this paper, we have experimentally and numerically investigated the effect of dispersing Copper Oxide nanoparticles into RT-35 filled a vertical cylindrical Thermal Energy Storage (TES) system. The TES system is consisted of two vertical cylindrical enclosures, which are attached to a thick acrylic plate. One of the enclosures is filled with pure PCM and the other one is filled with nano-PCM. The setup is insulated from the bottom and isothermally heated from its sides by using a constant temperature bath. To study more about the thermal and velocity fields, melting fraction and stored energy, a numerical simulation is conducted by using COMSOL Multiphysics software. It is concluded that although adding nanoparticles to PCM improves the melting rate, it is lowering the amount of energy stored inside the TES system.
Open Access
Coupled Orbital-Attitude Dynamics Of Flexible Electric Solar Wind Sail
(CSME-SCGM, May-18) Li, Gangqiang; Zhu, Zhenghong
This paper studies the dynamic characteristics of an electric solar wind propulsion system. To study the coupled interaction of the orbital and self-spinning motions of an electric solar wind propulsion system, a high-fidelity model is built up by using the nodal position finite element method, where the axial elastic and transverse dynamic motions of tether with the electric effects are considered. The coupling effects between the orbital and self-spinning motions are identified and explained, its results show that they have a significant impact on the system dynamics.
Open Access
Thermal management of PQ transformer for a passively cooled power module
(CSME-SCGM, May-18) Dey, Anshuman; Shafiei, Navid; Khandekar, Rahul; Lau, Kevin; Eberle, Wilson; Li, Ri
In this paper we study the thermal performance of a 5 kW rectifier module experimentally and numerically, with the aim of changing the cooling methodology from an active cooled (fan cooled) to a passively cooled system. Numerical model of the rectifier for fan cooled operation is developed and experimentally validated, following which the critical components in the system are identified. In this system, magnetic components like transformers were observed to have the poorest thermal performance. Given the lack of attention thermal management of magnetic components has received compared to switching components, we numerically study the thermal performance of a PQ 40/40 transformer in a passive (natural convection) scenario. Modifications to the transformer structure were studied and the heat transfer from the transformer was observed to be convection limited (large convection thermal resistance). Providing a minimum resistance conduction path from effective hot spot to ambient was observed to be the best practice. Further, providing a heat transfer path between the coil and core was observed to be crucial to transformer thermal performance.
Open Access
Influence Of Porosity And Alloy Addition On The Wear Behaviour Of A Sinter-Forged C45 Steel Using Taguchi Method
(CSME-SCGM, May-18) Easwaran, Naveen; Narasimha, Sripada Raghavendra Kesava
Elemental powders of Atomized Iron (Fe), Carbon (C) and Molybdenum (Mo) were weighed and mixed in a pot mill to yield the composition of C45, C45-1%Mo and C45-2%Mo Steels, then compacted and sintered. The Sintered preforms had a density- 75% of the Theoretical Density. Then the Sintered preforms were subjected to densification to get two densities- 80% and 85% of the theoretical density through Forging. The sintered and densified preforms of alloy steels are subsequently machined to get the required test specimens. The experiments were conducted on a pin-on-disc Tribometer, conforming to ASTM G99 standards, on a rotating EN32 disc. Using Minitab 16 software, the Dry Sliding wear experiments were planned using L27 Orthogonal Array. The % Theoretical Density of the Specimens, % Mo Addition, Load and Sliding Speed were taken as input parameters, mass loss was the output parameter. It was observed that the increasing density of alloy steels adversely affects the wear resistance of the alloy steels and mass loss is increased. It was found that the addition of Mo significantly improves the wear resistance of the alloy steels irrespective of the densities due to hard phase carbides present in the microstructure. Empirical correlations for mass loss with respect to input parameters had been developed using Regression Analysis. In the case of Mo added alloy, Mo particulates embedded between the ferrite-pearlite grains are observed from the microstructure.
Open Access
Computational Modelling Of Radiofrequency Cardiac Ablation To Study The Effect Of Cooling On Lesion Parameters
(CSME-SCGM, May-18) Berkmortel, Carolyn; Avari, Hamed; Savory, Eric
Radiofrequency ablation (RFA) is a technique used to treat cardiac arrhythmias. It creates lesions in the heart by creating thermal damage. Due to limitations associated with in vivo as well as in vitro studies, computational methods assist in further analysis of the problem by allowing for quicker and more diverse parametric studies and hence, a more thorough understanding of the physics involved. These computational models have been proven to be good representations of the process by accurately modelling the catheter with simplified geometry and boundary conditions. Although these studies have inconsistencies in material properties (due to the variation of thermal and mechanical properties in biological tissue) as well as different methods of creating the geometry and applying the boundary conditions, overall they are quite similar. The effects of esophageal cooling were investigated to understand its effect on the process. It was determined that using the standard model found within the literature, the esophageal cooling changed the lesion depth by less than 18%, while changing the maximum tissue temperature by as much as 13.4%.
Open Access
Improved Modal Contribution Factors As Response Tracking Mechanisms For Dynamic Systems During Design Optimization
(CSME-SCGM, May-18) Nieto, Michelle; Elsayed, Mostafa; Walch, Denis
As an industrial practice, complex structures are analyzed under a large set of dynamic operating conditions from which design load cases are selected. During design optimization, response tracking mechanisms based on modal participation factors could lead to large computational savings. In this paper we review the use of static modal participation factors as an inexpensive method to approximate the modal response of a dynamic system and extend the analysis to estimate the peak modal response when the structure is subject to a shock or pulse disturbances. A case study is presented as a proof of concept where the derived approximate peak loads are also estimated.
Open Access
The Influence of Powder Size and Packing Density on the Temperature Distribution in Selective Laser Melting
(CSME-SCGM, May-18) Moraes, Diego Augusto de; Czekanski, Aleksander
Metal powder properties in Selective Laser Melting (SLM) is among one of the most important factors when implementing new alloy developments for the equipment. In fact, not all commercially available metal powder alloys are ready to be implemented without a comprehensive set of tests. Besides the powder properties, we have a large number of building and environmental parameters that demands extensively research prior implementation. Although selected alloys are commercially available and documented to be used in SLM, including Ti6Al4V, SS316L and In718, the majority of it still not ready to be utilized in this system. The focus of this study is to use a thermal model in order to predict the thermal distribution of the process regarding different aspects of the powder properties, especially the thermal conductivity, when different powder packing densities and diameters are used. A Stainless Steel 304L will be utilized in this work, since it is not yet available to be commercially used. The main goal is to show the capabilities of the Finite Element Method in the pre-definition of optimal parameters for the process using a new alloy development. Our findings can be used as a pre-evaluation guideline when printing SS304L, since the comparison with similar experimental work in the field showed significant resemblance and outcomes. The temperature distributions show that the packing density has greater sensibility on the final temperature distributions, compared to the powder diameter variance. Two different power inputs are compiled and the temperature outcomes demonstrate that a power input of 100 Watts is recommended to use when printing SS304L, rather than 400 Watts that brings high temperature into the powder bed.
Open Access
Gust Response Of A Two-Dimensional Nonlinear Wing
(CSME-SCGM, May-18) Zhang, Xiaoyang; Kheiri, Mojtaba
In this paper, the equations of motion for a twodimensional (2-D) wing encountering a gust are presented. The wing has two degrees of freedom, i.e. pitch and plunge, and its motion is restrained by nonlinear translational and rotational springs. Two different stiffness nonlinearities are examined: (i) cubic and (ii) free play. For given system parameters, the responses of the nonlinear system to the sharp-edged and 1- cosine gust profiles are obtained at different flow velocities and compared to the time response of the system with no gust input.
Open Access
Direct Switching Position Control Algorithms For Pneumatic Actuators Using On/Off Solenoid Valves
(CSME-SCGM, May-18) Zhang, Yile; Bone, Gary M.
Pneumatic actuators are advantageous in terms of cost, power to weight ratio and inherent safety. However, their dynamics makes precise closed-loop position control very difficult in practice. Two sliding-mode control algorithms for controlling the position of a pneumatic cylinder by directly switching four on/off solenoid valves are proposed in this paper. The solenoid valves are much less expensive than the commonly used servo or proportional valves. The proposed algorithms are compared to two state of the art position control algorithms. Based on experiments on a high friction cylinder with various payloads, the proposed controllers provide superior performance in terms of valve switches per second, steady state error, settling time and overshoot. The achieved number of valve switches per second is also about one tenth of the number required by the pulse-width modulation method that is commonly used with on/off valves. This should result in prolonged valve lifetimes and reduced maintenance costs.
Open Access
A New Mechanical Band Pass Filter Design For Energy Harvesting
(CSME-SCGM, May-18) Keshmiri, Alireza; Wu, Nan
This work presents an analytical methodology for development of a mechanical band pass filter for energy scavenging. The model is based on Adomian decomposition method to derive the dynamic response of the non-uniform smart structure with strain rate damping to external environmental excitations and efficiently harvest the subsequent vibrational energy. The steady state response of the nonlinearly tapered cantilever beam subjected to a harmonic base motion is obtained and electromechanical outputs in open circuit condition are analytically derived. In other to design a band pass filter, an array of cantilever beams with nonlinear geometry and surface bonded piezoelectric layers are considered. Therefore, the filter can choose one harvester to resonate at one particular ambient vibration frequency and reach the maximum electromechanical output. Compared with uniform beam design, it is also demonstrated that the proposed non-uniform configuration can generate higher electrical output over a wide frequency range.
Open Access
Development Of Raw And Treated Flax Straw For Oil Spill Cleanup
(CSME-SCGM, May-18) Ghasemi, Pooya; Cree, Duncan; Ulrich, Alvin
An oil spill is a critical problem and appears to have increased in the number of incidence over the past decade. There are several methods for oil spill cleanups. One method is called sorption using either synthetic or natural sorbents. Synthetic sorbents are harmful to the environment as they create another form of waste for nature. This gives rise to evaluate a more environmentally friendly natural sorbent. This research represents the results of study carried out to evaluate the effect of chemical treatment (acetylation) on properties of flax straw as a natural fiber. Sorption capacity of untreated and chemically treated flax straw was examined. It was found that performing the acetylation treatment on flax straw, significantly increases oil sorption capacity in both light and heavy oil by 41% and 22% respectively and also decreases their water uptake by 5%. Moreover, by decreasing the particle size (to 0.6 mm) of the chopped flax straw, the oil sorption capacity increases. This research contributes to a greater understanding of flax straw properties for potential remediation and reclamation applications, representing the possibility of turning the available waste material into a valuable oil sorbent.
Open Access
Effect Of Photoacoustic Radar Chirp Parameters On Profilometric Information
(CSME-SCGM, May-18) Zuwen, Sun; Baddour, Natalie;
Continuous wave photoacoustics has been under investigation for more than a decade. Matched-filtering and pulse compression techniques, which use a chirp waveform as input light source, have been implemented into this imaging modality to improve signal to noise ratio (SNR) and resolution. However, the chirp parameters’ effects on SNR are still not clear. The theory behind chirp parameters’ effects on SNR is discussed in this paper. It is found that in order to get a higher SNR, chirp duration T should be maximized, chirp center frequency 0 f should be controlled to make the chirp spectrum overlap with absorber spectrum, and chirp bandwidth  should be smaller or equal to the absorber bandwidth.