Pub Date : 2019-11-14DOI: 10.34257/gjrefvol19is5pg1
L. Deng, Yongan Wang, Xudong Zhao, S. Li
The problem of conducted electromagnetic interference generated by high-power transformer cabinets is analyzed. Firstly, the equivalent model of the high-frequency circuit of conduction noise is established. The calculation method of noise current and voltage is described. Then the joint mode and differential mode conduction noise are analyzed. I am modeling as a theoretical basis for subsequent conduction noise extraction and separation. The method of suppressing conducted noise is studied, and the suppression effect of the filter on the noise of the AC output of the high-power transformer cabinet is analyzed, which provides a theoretical basis for the actual engineering rectification.
{"title":"Research on Conducted Electromagnetic Interference Mechanism Based on High Power Transformer Cabinet","authors":"L. Deng, Yongan Wang, Xudong Zhao, S. Li","doi":"10.34257/gjrefvol19is5pg1","DOIUrl":"https://doi.org/10.34257/gjrefvol19is5pg1","url":null,"abstract":"The problem of conducted electromagnetic interference generated by high-power transformer cabinets is analyzed. Firstly, the equivalent model of the high-frequency circuit of conduction noise is established. The calculation method of noise current and voltage is described. Then the joint mode and differential mode conduction noise are analyzed. I am modeling as a theoretical basis for subsequent conduction noise extraction and separation. The method of suppressing conducted noise is studied, and the suppression effect of the filter on the noise of the AC output of the high-power transformer cabinet is analyzed, which provides a theoretical basis for the actual engineering rectification.","PeriodicalId":342934,"journal":{"name":"Global Journal of Researches in Engineering","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124139493","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}
Pub Date : 2019-11-13DOI: 10.34257/gjreavol19is4pg25
E. Adiutori
This article describes alternate methodology for determining heat transfer correlations from experimental programs. In conventional methodology, the form of heat transfer correlations is determined before the experiment by deduction, and the experiment is performed in order to quantify constants in the deduced correlation form. In the proposed alternate methodology, the form of heat transfer correlations is determined after the experiment by induction. Three examples in the text apply the alternate methodology to data in the literature, and compare the resultant correlations to widely accepted correlations based on conventional methodology and the same data. The correlations that result from the alternate methodology agree with the underlying data much more accurately than correlations that result from conventional methodology. The difference in accuracy reflects the fact that deduction is much more difficult than induction, and therefore much more likely to include errors, and less likely to accurately describe the underlying data.
{"title":"A Critical Appraisal of Conventional Methodology used to Determine Heat Transfer Correlations, and Alternate Methodology","authors":"E. Adiutori","doi":"10.34257/gjreavol19is4pg25","DOIUrl":"https://doi.org/10.34257/gjreavol19is4pg25","url":null,"abstract":"This article describes alternate methodology for determining heat transfer correlations from experimental programs. In conventional methodology, the form of heat transfer correlations is determined before the experiment by deduction, and the experiment is performed in order to quantify constants in the deduced correlation form. In the proposed alternate methodology, the form of heat transfer correlations is determined after the experiment by induction. \u0000Three examples in the text apply the alternate methodology to data in the literature, and compare the resultant correlations to widely accepted correlations based on conventional methodology and the same data. The correlations that result from the alternate methodology agree with the underlying data much more accurately than correlations that result from conventional methodology. The difference in accuracy reflects the fact that deduction is much more difficult than induction, and therefore much more likely to include errors, and less likely to accurately describe the underlying data.","PeriodicalId":342934,"journal":{"name":"Global Journal of Researches in Engineering","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114539805","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}
Pub Date : 2019-11-13DOI: 10.34257/gjreavol19is4pg1
Shunichi Sakuragi, D. Torii
In recent years, in the cooling technology for high-power electronic devices such as power transistors used for drive motor control of electric vehicles and hybrid vehicles, a method of flowing a cooling fluid to a cooling substrate having a fin structure has become the main technology. The structure of the cooling fluid flow path is a channel flow through multiple narrow plate gaps to secure a heat transfer area. In this study, the heat transfer characteristics when the aspect ratio of the channel having a flat rectangular cross-section was changed were investigated in detail by experiments. Moreover, the difference in the heat transfer characteristic at the time of making a rectangular flow path into vertical installation and horizontal installation was also investigated.
{"title":"Effect of Aspect Ratio and Installation Direction on Channel Flow Heat Transfer Performance under a Wide Range of Reynolds Number","authors":"Shunichi Sakuragi, D. Torii","doi":"10.34257/gjreavol19is4pg1","DOIUrl":"https://doi.org/10.34257/gjreavol19is4pg1","url":null,"abstract":"In recent years, in the cooling technology for high-power electronic devices such as power transistors used for drive motor control of electric vehicles and hybrid vehicles, a method of flowing a cooling fluid to a cooling substrate having a fin structure has become the main technology. The structure of the cooling fluid flow path is a channel flow through multiple narrow plate gaps to secure a heat transfer area. In this study, the heat transfer characteristics when the aspect ratio of the channel having a flat rectangular cross-section was changed were investigated in detail by experiments. Moreover, the difference in the heat transfer characteristic at the time of making a rectangular flow path into vertical installation and horizontal installation was also investigated.","PeriodicalId":342934,"journal":{"name":"Global Journal of Researches in Engineering","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121272213","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}
Pub Date : 2019-11-05DOI: 10.34257/gjreevol19is4pg19
Prof. D. M. Dewaikar, Prof.V. B. Deshmukh
In this paper a detailed analysis of breakout resistance of a horizontally laid anchor plate in sandy soil is presented. To compute the distribution of soil reactive pressure on the failure surface, Kötter’s equation is employed. The failure surface is assumed to be in the form of a cone. An analytical expression for the breakout resistance is derived. Results are reported in terms of the breakout factors and net breakout resistance. A comparison is made with the available experimental data and theoretical solutions.
{"title":"Estimation of Uplift Capacity of Horizontal Plate Anchor in Sand","authors":"Prof. D. M. Dewaikar, Prof.V. B. Deshmukh","doi":"10.34257/gjreevol19is4pg19","DOIUrl":"https://doi.org/10.34257/gjreevol19is4pg19","url":null,"abstract":"In this paper a detailed analysis of breakout resistance of a horizontally laid anchor plate in sandy soil is presented. To compute the distribution of soil reactive pressure on the failure surface, Kötter’s equation is employed. The failure surface is assumed to be in the form of a cone. An analytical expression for the breakout resistance is derived. Results are reported in terms of the breakout factors and net breakout resistance. A comparison is made with the available experimental data and theoretical solutions.","PeriodicalId":342934,"journal":{"name":"Global Journal of Researches in Engineering","volume":"13 1-4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134265137","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}
Pub Date : 2019-11-04DOI: 10.34257/gjrejvol19is5pg31
R. R. Dias, I. Pereira, B. G. Soares
This article presents a review of the split Hopkinson pressure bar uses on evaluation of polymer composites ballistic material’s dynamic mechanical properties A small introduction concerning the equipment is given, followed by a summarization of the most recent published studies relating to dynamic compressive tests used to study dynamic properties of ballistic polymeric composites such as Young's modulus, maximum stress, strain at maximum stress, tenacity and maximum strain, as well as the sensitivity of these properties to changes in the applied strain rate.
{"title":"Use of the Split Hopkinson Pressure Bar on Performance Evaluation of Polymer Composites for Ballistic Protection Purposes","authors":"R. R. Dias, I. Pereira, B. G. Soares","doi":"10.34257/gjrejvol19is5pg31","DOIUrl":"https://doi.org/10.34257/gjrejvol19is5pg31","url":null,"abstract":"This article presents a review of the split Hopkinson pressure bar uses on evaluation of polymer composites ballistic material’s dynamic mechanical properties A small introduction concerning the equipment is given, followed by a summarization of the most recent published studies relating to dynamic compressive tests used to study dynamic properties of ballistic polymeric composites such as Young's modulus, maximum stress, strain at maximum stress, tenacity and maximum strain, as well as the sensitivity of these properties to changes in the applied strain rate.","PeriodicalId":342934,"journal":{"name":"Global Journal of Researches in Engineering","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125148677","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}
Pub Date : 2019-11-04DOI: 10.34257/gjrejvol19is5pg23
Bashar Khayrul, I. Nazmul, A. Saeed
Securing the modern lifestyle and embedding with the amenity and composure requires intelligent safety systems, that will be cognizant enough to sense and act on the anomaly of ambiance. Fire, undoubtedly, holds the most life-threatening risk when dispersing in an uncontrolled manner. This work represents the design and test of an intelligent fire control system for securing building or home, also fire control linkage system design, at the same time, it describes the following: the idea of the system designing, the system components, selecting equipment, the linkage of sensor and water extinguishing. This system uses different types of sensors and micro controlling devices that use the reservoir tank, pump, and piping system to deliver water and alarm systems to alert people. The result was taken at different temperatures, smoke levels, and flame existence levels. This will inspire the designing of intelligent systems with little investments and humanoid firefighters capable of extinguishing large fires.
{"title":"Design, Construction and Performance Test of an Automatic Fire Fighting System","authors":"Bashar Khayrul, I. Nazmul, A. Saeed","doi":"10.34257/gjrejvol19is5pg23","DOIUrl":"https://doi.org/10.34257/gjrejvol19is5pg23","url":null,"abstract":"Securing the modern lifestyle and embedding with the amenity and composure requires intelligent safety systems, that will be cognizant enough to sense and act on the anomaly of ambiance. Fire, undoubtedly, holds the most life-threatening risk when dispersing in an uncontrolled manner. This work represents the design and test of an intelligent fire control system for securing building or home, also fire control linkage system design, at the same time, it describes the following: the idea of the system designing, the system components, selecting equipment, the linkage of sensor and water extinguishing. This system uses different types of sensors and micro controlling devices that use the reservoir tank, pump, and piping system to deliver water and alarm systems to alert people. The result was taken at different temperatures, smoke levels, and flame existence levels. This will inspire the designing of intelligent systems with little investments and humanoid firefighters capable of extinguishing large fires.","PeriodicalId":342934,"journal":{"name":"Global Journal of Researches in Engineering","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126747342","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}
Pub Date : 2019-10-09DOI: 10.34257/gjrecvol19is2pg1
S. Dantas, F. Vittorino, K. Loh
The objective of this study was evaluation of the photocatalytic performance of the addition of n-TiO2 in white cement mortars in terms of the light reflection (evaluated by CIE L*a*b* scale) and reflectance of the mortar surfaces exposed to solar radiation in an urban environment. Are produced specimens of 1.2m × 1.2m with n-TiO2 additions of 1%, 5%, and 10% concerning to the total dry powder mass.The performances of the specimens were then compared with two sets without n-TiO2,painted and unpainted, and these were used as references. To conduct an in-situ experiment, the mortars were mixed and applied by a mason. After 41 months of exposure and washing of the specimens, the painted mortars and the mortars with the addition of different n-TiO2 contents exhibited a statistically equivalent reflectance under exposure to solar radiation. All specimens exhibited color differences resulting from: (i)the accumulation of dirt on the surface; (ii) an increase in the surface roughness of the specimens; and (iii)a decrease in rainfall over the duration of exposure.
{"title":"Photocatalytic Performance of White Cement Mortars Exposed in Urban Atmosphere","authors":"S. Dantas, F. Vittorino, K. Loh","doi":"10.34257/gjrecvol19is2pg1","DOIUrl":"https://doi.org/10.34257/gjrecvol19is2pg1","url":null,"abstract":"The objective of this study was evaluation of the photocatalytic performance of the addition of n-TiO2 in white cement mortars in terms of the light reflection (evaluated by CIE L*a*b* scale) and reflectance of the mortar surfaces exposed to solar radiation in an urban environment. Are produced specimens of 1.2m × 1.2m with n-TiO2 additions of 1%, 5%, and 10% concerning to the total dry powder mass.The performances of the specimens were then compared with two sets without n-TiO2,painted and unpainted, and these were used as references. To conduct an in-situ experiment, the mortars were mixed and applied by a mason. After 41 months of exposure and washing of the specimens, the painted mortars and the mortars with the addition of different n-TiO2 contents exhibited a statistically equivalent reflectance under exposure to solar radiation. All specimens exhibited color differences resulting from: (i)the accumulation of dirt on the surface; (ii) an increase in the surface roughness of the specimens; and (iii)a decrease in rainfall over the duration of exposure.","PeriodicalId":342934,"journal":{"name":"Global Journal of Researches in Engineering","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130066394","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}
Pub Date : 2019-09-25DOI: 10.34257/gjreavol19is3pg27
Marcus Vinícius Flores Soares, É. Nogueira
One of a major objective is to analyze the effect of internal and external convection coefficients in the heat transfer generated by electric motors and characterize intervals of feasible values, in practical terms, for these coefficients. Another objective is to determine the motor core temperature, considering the environmental and operational conditions of the motor installation and the heat flux Q0 (fixed) in the fins. To achieve the objectives were developed analytical solutions for determining the temperature variations in the fins, performance and electric motor efficiency, considering heat flow constant at the base of the fins and the possible variations in temperature of surround media. The heat flux at the base of the fins, in this case, is the minimum necessary for satisfactory electric motor performance and the core temperature is within the safety range stipulated by the manufacturer. The obtained results characterize a range of possible values for the inner and outer heat transfer coefficients.
{"title":"Finned Electric Motor with Prescribed Heat Flux and Influence of the Internal and External Heat Convection Coefficients on the Temperature of the Core","authors":"Marcus Vinícius Flores Soares, É. Nogueira","doi":"10.34257/gjreavol19is3pg27","DOIUrl":"https://doi.org/10.34257/gjreavol19is3pg27","url":null,"abstract":"One of a major objective is to analyze the effect of internal and external convection coefficients in the heat transfer generated by electric motors and characterize intervals of feasible values, in practical terms, for these coefficients. Another objective is to determine the motor core temperature, considering the environmental and operational conditions of the motor installation and the heat flux Q0 (fixed) in the fins. To achieve the objectives were developed analytical solutions for determining the temperature variations in the fins, performance and electric motor efficiency, considering heat flow constant at the base of the fins and the possible variations in temperature of surround media. The heat flux at the base of the fins, in this case, is the minimum necessary for satisfactory electric motor performance and the core temperature is within the safety range stipulated by the manufacturer. The obtained results characterize a range of possible values for the inner and outer heat transfer coefficients.","PeriodicalId":342934,"journal":{"name":"Global Journal of Researches in Engineering","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124466652","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}
Pub Date : 2019-09-25DOI: 10.34257/gjreavol19is3pg17
Muse Degefe Chewaka Liban, P. Paramasivam
This paper addressed that graphene is a regular monolayer of carbon atoms settled in a 2 D-hexagonal lattice; which is listed among the strongest material ever measured with strength exceeding more than hundred times of steel. However, the strength of graphene is critically influenced by temperature, geometric & vacancy defects (VD). Defects are at all believed to worsen the mechanical toughness and reduce the strength of graphene sheet. They are revealed that stiffness and strength are the key factors in determining solidity and life span of any technological devices. Molecular dynamics-based atomistic modeling was performed to predict and quantify the effect of non-bonded interactions on the failure morphology of vacancy affected sheets of graphene. The defective sheet of graphene containing vacancy defect was simulated in conjunction with the non-bonded interactions experienced due to the presence of a pristine sheet of graphene.
{"title":"Influence of Temperature with its Geometric and Failure Morphology Defects on the Mechanical Properties of Graphene: Molecular Dynamics Simulation (MDs)","authors":"Muse Degefe Chewaka Liban, P. Paramasivam","doi":"10.34257/gjreavol19is3pg17","DOIUrl":"https://doi.org/10.34257/gjreavol19is3pg17","url":null,"abstract":"This paper addressed that graphene is a regular monolayer of carbon atoms settled in a 2 D-hexagonal lattice; which is listed among the strongest material ever measured with strength exceeding more than hundred times of steel. However, the strength of graphene is critically influenced by temperature, geometric & vacancy defects (VD). Defects are at all believed to worsen the mechanical toughness and reduce the strength of graphene sheet. They are revealed that stiffness and strength are the key factors in determining solidity and life span of any technological devices. Molecular dynamics-based atomistic modeling was performed to predict and quantify the effect of non-bonded interactions on the failure morphology of vacancy affected sheets of graphene. The defective sheet of graphene containing vacancy defect was simulated in conjunction with the non-bonded interactions experienced due to the presence of a pristine sheet of graphene.","PeriodicalId":342934,"journal":{"name":"Global Journal of Researches in Engineering","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130909899","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}
Pub Date : 2019-09-20DOI: 10.34257/gjrefvol19is4pg35
Daniel L. Stevens
Digital intercept receivers are currently moving away from Fourier-based analysis and towards classical time frequency analysis techniques for the purpose of analyzing low probability of intercept radar signals. This paper presents the novel approach of characterizing low probability of intercept triangular modulated frequency modulated continuous wave radar signals through utilization and direct comparison of the Wigner Ville Distribution versus the Choi Williams Distribution. The following metrics were used for evaluation: percent error of: carrier frequency, modulation bandwidth, modulation period, chirp rate, and time-frequency localization (x and y direction). Also used were: percent detection, lowest signal-to noise ratio for signal detection, and plot (processing) time. Experimental results demonstrate that overall, the Wigner Ville Distribution produced more accurate characterization metrics than the Choi Williams Distribution. An improvement in performance may well translate into an increase in personnel safety.
{"title":"Low Probability of Intercept Triangular Modulated Frequency Modulated Continuous Wave Signal Characterization Comparison Using the Wigner Ville Distribution and the Choi Williams Distribution","authors":"Daniel L. Stevens","doi":"10.34257/gjrefvol19is4pg35","DOIUrl":"https://doi.org/10.34257/gjrefvol19is4pg35","url":null,"abstract":"Digital intercept receivers are currently moving away from Fourier-based analysis and towards classical time frequency analysis techniques for the purpose of analyzing low probability of intercept radar signals. This paper presents the novel approach of characterizing low probability of intercept triangular modulated frequency modulated continuous wave radar signals through utilization and direct comparison of the Wigner Ville Distribution versus the Choi Williams Distribution. The following metrics were used for evaluation: percent error of: carrier frequency, modulation bandwidth, modulation period, chirp rate, and time-frequency localization (x and y direction). Also used were: percent detection, lowest signal-to noise ratio for signal detection, and plot (processing) time. Experimental results demonstrate that overall, the Wigner Ville Distribution produced more accurate characterization metrics than the Choi Williams Distribution. An improvement in performance may well translate into an increase in personnel safety.","PeriodicalId":342934,"journal":{"name":"Global Journal of Researches in Engineering","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134365497","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}
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