Progress in Canadian Mechanical Engineering. Volume 3最新文献

{"title":"On the Prediction of Incubation Period in Water Droplet Erosion of Metals","authors":"Mohamed Ibrahim, M. Medraj","doi":"10.32393/csme.2020.72","DOIUrl":"https://doi.org/10.32393/csme.2020.72","url":null,"abstract":"Water droplet erosion (WDE) is a phenomenon of material loss caused by the repetitive impact of high speed droplets. WDE constitutes a major concern for several industries such as wind energy and efforts to understand the fundamental causes of the phenomenon and methods to combat it are necessary research directions. Essential to combating WDE phenomenon is the ability to predict its onset. This is because erosion damage begins only after an “incubation period” during which stresses are accumulated to the amount necessary to initiate erosion damages. This work presents a model that predicts the number of impacts necessary to end the incubation period. As a prior step, erosion experiments were performed on several metallic materials of known mechanical properties with the aim to identify the target mechanical properties that control materials’ resistance to erosion. Experimental data from the literature as well as from our group’s earlier studies has also been analyzed to understand the weightages with which the impact parameters (mainly impact velocity and droplet size) affect the incubation period. The model is then developed to predict the incubation period as a function of impact velocity, droplet size, and properties of the target material. So far, it has been observed that fatigue endurance limit, fracture toughness, hardness, and the elastic modulus are the target properties governing the erosion incubation resistance of metallic materials. It was also found that the resistance to the onset of erosion damage decreases as a function of impact velocity to power 4. The incubation period model has also been compared with three other models from the literature. This work is a part of an ongoing research and preliminary results obtained so far will be presented. These current findings are essential for the development of a full water droplet erosion model which is the overall objective of this work.","PeriodicalId":184087,"journal":{"name":"Progress in Canadian Mechanical Engineering. Volume 3","volume":"13 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123218301","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design of a 2D Ahmed Body Rear Surface to Optimize Drag and Downforce Using Multi-objective Genetic Algorithm","authors":"R. Aranha, Anton Alconl, Kais Abdulmawjood, Martin Angelin-Chaab","doi":"10.32393/csme.2020.1159","DOIUrl":"https://doi.org/10.32393/csme.2020.1159","url":null,"abstract":"In the design of race cars or airplanes the aerodynamics, such as its rear surface, is important to achieve the best performance possible. The objective of this paper was to optimize the rear surface design of a two-dimensional body (2D) to reduce drag and lift (to improve downforce) utilizing a metaheuristic optimization program. Drag and lift shape optimization can be solved using a multi-objective algorithm in which the primary objectives were to minimize the drag and the lift (to improve the downforce). To develop the program, the test shape used was an Ahmed Body box that was fixed without any tilt (0 degrees relative to the horizontal axis), where the rear surface was defined as five (5) equally spaced points for shape optimization. Alteration of the 5 points were constrained to change within 400mm in the positive or negative direction from the reference vertical axis. To achieve optimization, the program was designed to optimize the shape using an Evolutionary Algorithm (EA) - the Elitist Non-Dominated Sorting Genetic Algorithm (NSGA - II). The following parameters were fixed during initialization of the program: number of points for the rear surface, flow velocity, max allowed result. The program began optimization, by generating random candidate surface shapes. Then those candidate solutions were smoothed by the B-Spline function, utilizing applied CFD through the use of OpenFOAM. The program then compared the results and generated new candidate shapes to be tested until 40 generations (for each Reynolds number generated) were produced and the pareto progress was tracked for candidate solution comparison. This resulted in optimized shapes that are similar to experimentally tested and proven shapes that are shaped like a diffuser (as expected) that demonstrated the validity of the program.","PeriodicalId":184087,"journal":{"name":"Progress in Canadian Mechanical Engineering. Volume 3","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124136778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical Study of the Fluid Dynamics of a Micro Pillar Immersed in a Laminar Boundary Layer","authors":"M. Yaras, Cagri Metin","doi":"10.32393/csme.2020.59","DOIUrl":"https://doi.org/10.32393/csme.2020.59","url":null,"abstract":"— The study investigates the flow development in the vicinity and wake of a micro pillar mounted on a surface immersed in the inner region of a laminar boundary layer. The investigation is based on the numerical solution of the Navier Stokes equations for incompressible conditions. It is demonstrated that the significant wall-normal gradient of streamwise velocity of the cross flow spanning the height of the micro pillar results in suppression of time-periodic shedding of vorticity from the side surfaces of the micro pillar, resulting in a steady wake flow. A pair of streamwise-oriented tip vortices and a corresponding pair of base vortices are observed to dominate the wake development. The sources of vorticity for these vortices and their relation to the vorticity in the recirculation zone immediately downstream of the micro pillar are identified. This improved understanding of flow physics is intended to inform future studies of passive control of boundary layers.","PeriodicalId":184087,"journal":{"name":"Progress in Canadian Mechanical Engineering. Volume 3","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121416998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identifying the Impacts of Strategic Wind Farm Maintenance on its Capacity Value","authors":"David Kiefte, Lukas Swan, N. Pearre","doi":"10.32393/csme.2020.1134","DOIUrl":"https://doi.org/10.32393/csme.2020.1134","url":null,"abstract":"Wind farms in Nova Scotia create revenue based on the energy generated, independent of the time of delivery. Most wind farm operators schedule their maintenance during low wind resource periods to maximize production/revenue. These low resource periods can coincide with high electrical load periods which is disadvantageous to the utility supplying that load. A certain wind farm in Nova Scotia attempts to avoid scheduled maintenance during these high-load periods. We evaluate the output of this wind farm compared to other Nova Scotia wind farms to see if this strategy improves the “capacity value” by generating during high load periods. The wind farms span much of mainland Nova Scotia. Data was collected from Supervisory Control and Data Acquisition (SCADA) systems on wind turbines and electrical substations. We also obtained total provincial electrical load from the electricity utility. The data were first normalized by dividing time-series production by the rated capacity of each farm. To examine the reliable capacity of each wind farm, normalized production during the highest 10% of load times was characterized by its 10 th percentile, 5 th percentile, and 1 st percentile production, i.e., the production available on at least 90%, 95%, and 99% of such high-load times. This procedure was then repeated for the 5% highest load times, 1% and 0.5%, to see how the data behaved as the range shortened. Reliable capacity during high load periods is of interest to policy makers and electricity planners. We find that the reliable capacity of all of the wind farms increased dramatically as analysis focused on progressively higher and higher load times. This suggests that high winds contribute to provincial loads, which is likely related to wind increasing convection and cold air intrusion in buildings, so increasing heating loads. However, the analysis found that the specific wind farm with strategic scheduling of maintenance does not offer significantly better reliability than the other wind farms. The impact of strategic maintenance is not large enough relative to exogeneous differences between wind farms to result in better production during high load times. We conjecture that wind farm location has a higher impact than maintenance timing, and that a correlation between high wind speeds and high loads makes it an algorithmic distinction without an operational difference.","PeriodicalId":184087,"journal":{"name":"Progress in Canadian Mechanical Engineering. Volume 3","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116582862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a Control and Estimation Strategy for a Six-Link Robot Manipulator","authors":"Grant Hall, Andrew S. Lee, S. Gadsden","doi":"10.32393/csme.2020.1209","DOIUrl":"https://doi.org/10.32393/csme.2020.1209","url":null,"abstract":"— This paper covers the ongoing approach of creating new combinations of robot controllers with filtering techniques. It outlines the need for such a system and a current controller system that uses filtering techniques to improve accuracy. It also explains how the proposed approach differs from the systems in literature. This paper outlines how the system is designed and tested. It explains the approach taken to design a system, and how the performance of the system will be measured. Finally, it explains progress that has been achieved, as well as recommendations for future work.","PeriodicalId":184087,"journal":{"name":"Progress in Canadian Mechanical Engineering. Volume 3","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114320297","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Viability of using Convolutional Neural Networks for Real-Time Fescue and Sheep Sorrel Detection in Wild Blueberry Fields","authors":"Patrick Hennessy, T. Esau, Q. Zaman, K. Corscadden, A. Schumann, A. Farooque","doi":"10.32393/csme.2020.1184","DOIUrl":"https://doi.org/10.32393/csme.2020.1184","url":null,"abstract":"Wild blueberry (Vaccinium angustifolium Ait.) production is hindered by weeds such as fescue (Festuca filiformis Pourr.) and sheep sorrel (Rumex acetosella L.). Commercial sprayers provide a uniform application of herbicide regardless of the incidence of weed coverage. Traditional methods of spot-applying herbicide to target weed locations relied on colour co-occurrence matrices that were limited by long processing times in addition to green colour segmentation lacking the ability to discriminate between weeds and crop canopy of similar colour. Deep learning convolutional neural networks (CNNs) are a modern processing technique which often uses powerful graphics processing units (GPUs) to classify images or detect objects within images. This novel research study featured two object-detection CNNs, YOLOv3 and YOLOv3-Tiny, trained to detect fescue using images of wild blueberry fields captured during application timing intervals in the 2019 growing season. A custom-built desktop computer using the Ubuntu 16.04 operating system and an NVIDIA GeForce RTX 2080 Ti GPU was used to test the CNNs using 1280x720 resolution images. YOLOv3 classified fescue images with an F1-score of 0.95 and YOLOv3-Tiny classified fescue images with an F1-score of 0.97. YOLOv3 and YOLOv3-Tiny classified sheep sorrel images with F1scores of 0.93 and 0.89 respectively. A laptop running Windows 10 Pro with an NVIDIA Quadro RTX 5000 GPU was used to process video streams from four USB cameras simultaneously. YOLOv3 processed each video stream at an average framerate of 4.7 FPS using 9.2 GB of vRAM, while YOLOv3-Tiny processed each video stream at an average framerate of 20.5 FPS using 3.2 GB of vRAM. Initial results suggest that YOLOv3-Tiny can be deployed for use with a machine vision system to detect fescue and sheep sorrel in realtime for spot application of herbicide in wild blueberry fields. Using CNNs to selectively spray herbicide will appreciably reduce the volume of herbicides needed to manage wild blueberry fields, resulting in cost-savings for producers. Keywords—Deep learning; artificial intelligence; machine vision; precision agriculture; weed detection","PeriodicalId":184087,"journal":{"name":"Progress in Canadian Mechanical Engineering. Volume 3","volume":"80 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130122421","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Jordan Forms in Vehicle Dynamics","authors":"B. Minaker","doi":"10.32393/csme.2020.93","DOIUrl":"https://doi.org/10.32393/csme.2020.93","url":null,"abstract":"— In the ongoing search for mathematically efficient methods of predicting the motion of vehicle and other multibody systems, and presenting the associated results, one of the avenues of continued interest is the linearization of the equations of motion. While linearization can potentially result in reduced fidelity in the model, the benefits in computational speed often make it the pragmatic choice. When representing the governing equations of any linear system, one of the relevant problems is the determination of the mathematically equivalent formulation of the smallest size, and solving this system is the most mathematically efficient manner. This paper discusses and explores the potential of an approach based on modal identification, and the Jordan form of the system matrix. The paper includes an example where the method is applied to the classic linear bicycle model.","PeriodicalId":184087,"journal":{"name":"Progress in Canadian Mechanical Engineering. Volume 3","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131101440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"RANS Simulation of HAWT Immersed on ABL Flow under Neutral and Stratified Conditions Using OpenFOAM","authors":"M. N. Hamlaoui, H. Fellouah, A. Smaili","doi":"10.32393/csme.2020.1186","DOIUrl":"https://doi.org/10.32393/csme.2020.1186","url":null,"abstract":"This paper proposes numerical method for aerodynamic performance predictions of Horizontal Axis Wind Turbines (HAWT) immersed on Atmospheric Boundary Layer (ABL) flows under unstable, stable and neutral conditions. The flow field has been described using the three-dimensional RANS equations complemented by the k   turbulence model with modified constants corresponding to ABL flows. The density variation has been introduced into the momentum equation using the Boussinesq approximation and appropriate buoyancy term has been included. The equation of energy based on potential temperature has been implemented and solved to take into account the effect of temperature on the flow field (turbulence). The ABL profiles ( , k  , Velocity and Temperature) under neutral and stratified conditions has been implemented into OpenFOAM based on Monin-Obukhov similarity. The flow over the fetch has been calculated through an in-house solver (ABLSolversimpleFoam) developed with OpenFOAM for steady-state turbulent flows. Comparison between the solutions of the ABL proposed by the present method and the empirical relations based on Monin-Obukhov similarity theory has been carried out by giving good accuracy. The immersed HAWT has been modeled using the actuator disc approach where the swept surface of the rotor is replaced by surface forces that act upon the incoming flow according to the Blade Element theory. The Blade Element theory uses the two dimensional aerodynamic coefficients which produce under predictions of the power output at high incoming wind speeds. Du and Selig stall delay model has been implemented to take into account the effect of rotation. The obtained results have indicated that the velocity defect in the wake of a wind turbine is more significant in unstable than in stable thermal","PeriodicalId":184087,"journal":{"name":"Progress in Canadian Mechanical Engineering. Volume 3","volume":"153 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134313203","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Small-Scale Experimental Model of a Helical Steel Pile as the Heat Exchanger in Ground Source Heat Pumps","authors":"L. Kober, S. Nicholson, Sylvie Antoun, S. Dworkin","doi":"10.32393/csme.2020.1189","DOIUrl":"https://doi.org/10.32393/csme.2020.1189","url":null,"abstract":"Ground Source Heat Pump (GSHP) technologies are a way to obtain clean, renewable energy to heat and cool buildings by using the moderate year-round temperature of the ground as a heat-transfer medium. Across Canada, there is great potential to implement GSHPs due to soil conditions and an increasing demand for sustainable energy, especially in northern regions where conventional heating and cooling systems running on fuel are nearing their end-of-life. However, for these technologies to be more appealing in Canada, they need to be made more economically efficient, since high costs are a limiting factor in their implementation. As a solution, helical steel piles may be used in place of deep boreholes as the primary heat exchangers in the GSHP system, as well as for structural support for building foundations. With the dual functionality of helical steel piles, there is potential to save materials and reduce associated costs. To explore the thermodynamic capabilities of helical steel piles in GSHPs, a small-scale model of a complete single helical steel pile with a custom internal pipe layout was created with the combination of 3D printing and custom machining. The model pile was placed in a tank of soil medium and put in an insulated jacket to simulate soil conditions of the ground and minimize external interference. With sensors to measure temperatures and fluid flow, a variety of tests were run on the small-scale model to imitate field operation. Both laminar and turbulent flows were used to measure the effects of flow conditions on heat exchange performance. Alongside observing the effects of changing flow rates, the temperature distribution in the soil medium was measured radially. Currently, there is no this pile setup, so this research is essential for influencing possible design, operation, and future improvements to the equipment. The temperature gradients measured in the soil will inform spacing of the","PeriodicalId":184087,"journal":{"name":"Progress in Canadian Mechanical Engineering. Volume 3","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123820847","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Non-Linear Poisson Function for Natural Rubbers","authors":"E. Gkouti, B. Yenigun, K. Jankowski, A. Czekanski","doi":"10.32393/csme.2020.69","DOIUrl":"https://doi.org/10.32393/csme.2020.69","url":null,"abstract":"—In linear elasticity, Poisson’s ratio is one of the physical constants which characterizes an isotropic material, as it describes its lateral contractive response in infinitesimal strain. It has been proved that the use of this constant is limited, for several application where a material is subjected to large deformation. In this case, a scalar function of deformation can be defined, known as Poisson’s function, but the strain tensor must be calculated first. Due to various existing strain tensors, several Poisson’s functions are calculated to describe the negative strain tensor in the orthogonal direction, divided to the strain tensor in the axial direction, where the force is applied. Selected experimental tests are performed for elastomers under simple tension and the resulting Poisson’s functions are shown for different strain tensors.","PeriodicalId":184087,"journal":{"name":"Progress in Canadian Mechanical Engineering. Volume 3","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134471770","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}