Journal of Mechanical Engineering Research and Developments最新文献

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MODELING AND EXPERIMENTAL VALIDATION OF VALVE AND PUMPING ACTUATOR OF A PIEZO-HYDRAULIC PUMP 压电液压泵阀及泵动器的建模与实验验证
Journal of Mechanical Engineering Research and Developments Pub Date : 2019-08-29 DOI: 10.26480/jmerd.05.2019.110.114
S. Nayak, R. Muralidhara
{"title":"MODELING AND EXPERIMENTAL VALIDATION OF VALVE AND PUMPING ACTUATOR OF A PIEZO-HYDRAULIC PUMP","authors":"S. Nayak, R. Muralidhara","doi":"10.26480/jmerd.05.2019.110.114","DOIUrl":"https://doi.org/10.26480/jmerd.05.2019.110.114","url":null,"abstract":"This paper presents experimental investigations on valve actuator and pumping actuator of a piezo-hydraulic pump with active valves. Quadratic arm flexurally amplified piezoelectric actuators (QAFAPA) are designed for the pumping actuator and the valve actuator. Simulations are carried out to determine the voltage-displacement characteristics of the QAFAPA using MATLAB/Simulink software. To perform the pumping action, slotted pumping diaphragm is designed considering acrylic as the material and is analyzed for its stiffness using ANSYS analysis software. The slotted pumping diaphragm is fabricated, and the stiffness is experimentally determined which matched well with the analysis result. One pumping actuator and one actuator similar for inlet and outlet valve is developed. Voltage-displacement experiments are carried out on the valve actuator and the pumping actuator. Further, the displacement of the slotted pumping diaphragm when assembled with pumping actuator is experimentally determined. Simulation and experimental results were compared, and the results obtained were in good agreement with each other.","PeriodicalId":16153,"journal":{"name":"Journal of Mechanical Engineering Research and Developments","volume":"170 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86802071","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}
引用次数: 2
TRANSIENT RESPONSE OF ROTOR SYSTEM UNDER DIFFERENT STARTUP SPEED PROFILES 不同启动转速工况下转子系统的瞬态响应
Journal of Mechanical Engineering Research and Developments Pub Date : 2019-08-29 DOI: 10.26480/jmerd.05.2019.163.167
F. O. Hamdoon, H. Al-Bugharbee, A. S. Hameed
{"title":"TRANSIENT RESPONSE OF ROTOR SYSTEM UNDER DIFFERENT STARTUP SPEED PROFILES","authors":"F. O. Hamdoon, H. Al-Bugharbee, A. S. Hameed","doi":"10.26480/jmerd.05.2019.163.167","DOIUrl":"https://doi.org/10.26480/jmerd.05.2019.163.167","url":null,"abstract":"During startup process of rotating machinery and due to the rotor’s inherent unbalance, transient vibration is introduced as the machinery passes through critical speeds. In the present paper, time domain simulation is performed using ANSYS software to investigate the transient unbalance response of rotor – bearing system. The transient vibration response of the rotor system passing through the critical speeds is analysed under different startup speed profiles. Startup speed profile is represented by exponential formula with single parameter (δ) that indicates whether the startup speed is rapid or slow. The results show that for slow machine startup; the system will remain at the critical speeds for a long period allowing the vibration response to be increased. On the other hand, rapid machine startup passing through the critical speeds will reduce the vibration response. In addition, the numerical simulation results show that applying initial slow startup speed profile followed by instantaneous switch to rapid startup speed profile can reduce the vibration response significantly and more than for applying only rapid startup speed profile.","PeriodicalId":16153,"journal":{"name":"Journal of Mechanical Engineering Research and Developments","volume":"25 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86003747","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}
引用次数: 0
ADVANCED TECHNOLOGY SOLUTIONS FOR TREATMENT AND CONTROL NOXIOUS EMISSION OF LARGE MARINE DIESEL ENGINES: A BRIEF REVIEW 大型船用柴油机有害排放处理与控制的先进技术解决方案综述
Journal of Mechanical Engineering Research and Developments Pub Date : 2019-08-29 DOI: 10.26480/jmerd.05.2019.21.27
V. Pham
{"title":"ADVANCED TECHNOLOGY SOLUTIONS FOR TREATMENT AND CONTROL NOXIOUS EMISSION OF LARGE MARINE DIESEL ENGINES: A BRIEF REVIEW","authors":"V. Pham","doi":"10.26480/jmerd.05.2019.21.27","DOIUrl":"https://doi.org/10.26480/jmerd.05.2019.21.27","url":null,"abstract":"Large marine diesel engines use low-quality fuel, significant sulfur content, when conducting combustion with air in the combustion chamber will emit different combustion products. The main components of air pollution in diesel exhaust include NOx, SOx, CO, HC, and PM. The amount of NOx, CO, SOx, and HC in the emission from the internal combustion engine up to 50%. These pollutants directly affect human health and the environment. The World Maritime Organization (IMO) has introduced the mandatory standards in Annex VI of MARPOL 73/78, to regulate the standard of toxic substances in diesel emissions. Many technology solutions are being applied by Man B&W, Wartsila, Mitsubishi, Yanmar, Weichai, MTU, Carterpillar ... to treat and control toxic gases from marine diesel engines. The article provides an overview of environmental pollution caused by NOx, SOx and HC in exhaust emissions from marine diesel engines, and also provides advanced technology solutions by significant engine manufacturers in the world that have used to minimize noxious emissions of marine diesel engines. Moreover, the author provides and evaluates the solutions applied to Vietnam's inland waterway fleet to enhance the control of toxic emissions, ensuring the mandatory standards in Annex VI of the MARPOL Convention.","PeriodicalId":16153,"journal":{"name":"Journal of Mechanical Engineering Research and Developments","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90535399","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}
引用次数: 15
A MINI REVIEW ON THE ENGINE DEPOSITS AND ITS EFFECT ON HEAT TRANSFER 简要回顾了发动机沉积物及其对传热的影响
Journal of Mechanical Engineering Research and Developments Pub Date : 2019-08-29 DOI: 10.26480/jmerd.05.2019.158.162
Thanh H. Truong, V. V. Le
{"title":"A MINI REVIEW ON THE ENGINE DEPOSITS AND ITS EFFECT ON HEAT TRANSFER","authors":"Thanh H. Truong, V. V. Le","doi":"10.26480/jmerd.05.2019.158.162","DOIUrl":"https://doi.org/10.26480/jmerd.05.2019.158.162","url":null,"abstract":"Deposit, which is found in the combustion chamber of the internal combustion engines after operating hundred hours, causes many various issues such as reduce in the engine power and performance, reduce in ability of heat transfer, reduce in conduction rate but increase in toxic emissions content. Deposits accumulating in the end gas areas, on exhaust valves, and in cylinders with high oil consumption can be distinguished by comparison of H/C atom ratios, carbon content and inorganic compound content. Differences in deposit composition can be observed between engine families and between driving cycles with the same engine family. Besides, deposit also causes the jam between the motive mechanical parts in engine combustion chamber, even cause the abnormal combustion. The study of deposit formation and structure is necessary in order to find out the method aiming for overcoming the negative influence on the engines. The paper presents a review of deposit, the deposit formation and structure are mentioned by many researches and aggregated in this work. Findings of paper not only enrich the knowledge about the engine deposit but also are potential to carry out an experimental set up in order to estimate, calculate the ability of forming the deposit on a same condition as in the engine combustion chamber.","PeriodicalId":16153,"journal":{"name":"Journal of Mechanical Engineering Research and Developments","volume":"40 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77862935","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}
引用次数: 1
SOLUTIONS FOR THE UNSTABLE WORKING OF A TURBOCHARGER IN MARINE DIESEL ENGINES 船用柴油机涡轮增压器工作不稳定的解决方法
Journal of Mechanical Engineering Research and Developments Pub Date : 2019-08-29 DOI: 10.26480/jmerd.05.2019.42.45
V. V. Le, Thanh H. Truong
{"title":"SOLUTIONS FOR THE UNSTABLE WORKING OF A TURBOCHARGER IN MARINE DIESEL ENGINES","authors":"V. V. Le, Thanh H. Truong","doi":"10.26480/jmerd.05.2019.42.45","DOIUrl":"https://doi.org/10.26480/jmerd.05.2019.42.45","url":null,"abstract":"We know the development trend of industries in general and the shipbuilding industry, in particular, is the increase in energy efficiency to contribute to global emissions reduction, especially CO2 emissions. It is not difficult to realize that gas turbines utilize exhaust gas energy to increase the intake air pressure. Exhaust gas turbines are convenient enough to complete the shipbuilding industry in line with the norms of the world maritime organization, including EEDI (energy efficiency design index) and SEEMP (ship energy efficiency management plan). Thus, satisfying IMO's EEDI and SEEMP criteria under MARPOL Annex VI, the completion of the design and exploitation of turbocharged exhaust turbines should be a top priority. Exhaust gas turbines increase the intake air pressure to improve the performance of diesel engines, so it is almost present on most diesel engines. Mastering the structure and working principles to improve the efficiency of turbines continuously is an urgent requirement. Besides, it is necessary to follow the manufacturer's instructions and research to effectively exploit turbines that will contribute to increasing economic efficiency and contributing to reducing environmental pollution emissions. The article focuses on analyzing measures to overcome the causes of working instability of the main diesel engine's exhaust gas turbine, which will contribute a small part in completing exhaust gas turbines. Based on mastering the knowledge of exhaust gas turbine, we can choose the turbine layout to utilize exhaust gas heat suitable for diesel engines. Moreover, mastering the factors that affect the working of turbines and compressors, thereby improving the quality of turbine extraction and maintenance to ensure they always work in the best conditions.","PeriodicalId":16153,"journal":{"name":"Journal of Mechanical Engineering Research and Developments","volume":"149 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75754942","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}
引用次数: 0
REDUCTION OF PRODUCTION CYCLE TIME OF WIND TURBINE BLADES 缩短风机叶片的生产周期
Journal of Mechanical Engineering Research and Developments Pub Date : 2019-08-29 DOI: 10.26480/jmerd.05.2019.97.100
S. Karinka, Aniketan Bekal, Rakesh ., S. Acharya
{"title":"REDUCTION OF PRODUCTION CYCLE TIME OF WIND TURBINE BLADES","authors":"S. Karinka, Aniketan Bekal, Rakesh ., S. Acharya","doi":"10.26480/jmerd.05.2019.97.100","DOIUrl":"https://doi.org/10.26480/jmerd.05.2019.97.100","url":null,"abstract":"For any manufacturing industry, cycle time optimization is very important in order to maximize the production capacity with the effective use of time. The objective of this project is to calculate and analyze cycle time of main moulding process of wind turbine blade of 50 meters and above length. The time analysis was made by noting down start and end time of each event in moulding process. The time analysis data, which was taken, was transferred to excel sheets and Gap analysis and Pareto charts were drawn. Based on the data gathered, delay time was analyzed for each event in the process and also the key factors which caused the delay was found. The result obtained from the chart can be used to reduce the key factors which caused the delay in the production time. From the data collected and analyzed, it can be concluded that the major delay reasons in the main moulding process is due to layer missing from MPRP (Material preparation), repairs, x-shell induced delay. Humidity is also found to be a major contributor to delay in monsoon.","PeriodicalId":16153,"journal":{"name":"Journal of Mechanical Engineering Research and Developments","volume":"26 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76128403","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}
引用次数: 1
CLOSED-LOOP COMBUSTION CONTROL IN PPCI ENGINE ppci发动机的闭环燃烧控制
Journal of Mechanical Engineering Research and Developments Pub Date : 2019-08-29 DOI: 10.26480/jmerd.05.2019.70.73
Dao Nam Cao
{"title":"CLOSED-LOOP COMBUSTION CONTROL IN PPCI ENGINE","authors":"Dao Nam Cao","doi":"10.26480/jmerd.05.2019.70.73","DOIUrl":"https://doi.org/10.26480/jmerd.05.2019.70.73","url":null,"abstract":"Low-temperature combustion (LTC) is a method which describes extremely low NOx and soot concentrations in an internal combustion engine. Absolutely, the element that mainly affects to mixture fuel-air premixed and combustion in PPCI engines is chemical kinetics. In PPCI combustion, the pressure, and temperature of the mixture inside the cylinder influence the duration of combustion. This study describes closed-loop combustion control in PPCI engines. Initially, control variables are necessary for this method. Secondly, it considers the combustion feedback sensors and control drives burn. The final section presents the PPCI closed-loop combustion control method.","PeriodicalId":16153,"journal":{"name":"Journal of Mechanical Engineering Research and Developments","volume":"212 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76148601","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}
引用次数: 0
FLEXURAL AND QUASI-STATIC COMPRESSIVE BEHAVIOR OF INJECTION-MOLDED WALNUT SHELL (WS)/HDPE COMPOSITES 注射成型核桃壳/高密度聚乙烯复合材料的弯曲和准静态压缩性能
Journal of Mechanical Engineering Research and Developments Pub Date : 2019-08-29 DOI: 10.26480/jmerd.05.2019.93.96
Suprit Malagi, Rajesh Anawal, S. V. Gorabal, M. Doddamani
{"title":"FLEXURAL AND QUASI-STATIC COMPRESSIVE BEHAVIOR OF INJECTION-MOLDED WALNUT SHELL (WS)/HDPE COMPOSITES","authors":"Suprit Malagi, Rajesh Anawal, S. V. Gorabal, M. Doddamani","doi":"10.26480/jmerd.05.2019.93.96","DOIUrl":"https://doi.org/10.26480/jmerd.05.2019.93.96","url":null,"abstract":"The present study focuses on flexural and quasi-static compression behavior of high-density polyethylene (HDPE)/walnut shell (WS) composites. Flexural and quasi-static compression specimens by 20, 40 and 60 wt. % of WS are synthesized by polymer injection (PI) molding. The flexural modulus and strength are observed to increase with increase in the wt.% of WS. Compared to pure HDPE, the flexural modulus and strength increased in the range of 205-403% and 49-58% respectively. Further quasi-static compression tests are carried at 0.001, 0.01, 0.1 s-1 strain rates. Compressive modulus of HDPE/WS specimens is lower as compared to pure HDPE samples for all the strain rates. Compressive yield strength of HDPE/WS specimens shows increasing trend with increase in the strain rates. Scanning electron microscopy (SEM) is employed to study the fractography of the samples.","PeriodicalId":16153,"journal":{"name":"Journal of Mechanical Engineering Research and Developments","volume":"44 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79209384","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}
引用次数: 0
APPLICATION OF CFD FOR CALCULATION AND SIMULATION OF ANCHOR-CABLE TENSIONS IN MOORING SHIP CFD在系泊船舶锚索张力计算与模拟中的应用
Journal of Mechanical Engineering Research and Developments Pub Date : 2019-08-29 DOI: 10.26480/jmerd.05.2019.182.186
Nguyen Dang Khoa Pham, X. Nguyen
{"title":"APPLICATION OF CFD FOR CALCULATION AND SIMULATION OF ANCHOR-CABLE TENSIONS IN MOORING SHIP","authors":"Nguyen Dang Khoa Pham, X. Nguyen","doi":"10.26480/jmerd.05.2019.182.186","DOIUrl":"https://doi.org/10.26480/jmerd.05.2019.182.186","url":null,"abstract":"Computational Fluid Dynamics was applied to early hydrodynamics research, and the name CFD originated here. CFD has been developed, applied, and highly effective in the fields of fluid mechanics and deformation and elastic environments. CFDs are widely applied in advanced sciences and high technology as well as maritime sciences. In recent years, many scientists have effectively exploited and applied CFD and numerical methods for calculating and simulating the hydrodynamics of ocean current on ships. Simulating studies on the effect of ocean current on the tension of anchor-cable by CFD are becoming more and more popular. In this paper, from the theoretical basis related to the tension problem of mooring cables, the authors have proposed a simulation model that applies CFD to research and develop simulation model and calculate tension of cables in mooring ship. The goal of this study is to build a simulation model that is closest to reality so that we can study assumptions of different situations. Also, the achieved results will be the basis for proposing warnings to minimize marine accidents at the mooring area at the ports in Vung Tau, especially for tanker fleets. The authors have developed general implementation procedures, and specific calculations for several different input cases on a ship hull based on data of wind and flow characteristics at Vung Tau anchorage area, namely the oil tanker M/T AULAC JUPITER of Au Lac Joint Stock Company.","PeriodicalId":16153,"journal":{"name":"Journal of Mechanical Engineering Research and Developments","volume":"73 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80359485","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}
引用次数: 7
AN OVERVIEW STUDY ON THE LASER TECHNOLOGY AND APPLICATIONS IN THE MECHANICAL AND MACHINE MANUFACTURING INDUSTRY 综述了激光技术及其在机械制造业中的应用
Journal of Mechanical Engineering Research and Developments Pub Date : 2019-08-29 DOI: 10.26480/jmerd.05.2019.16.20
M. Chau
{"title":"AN OVERVIEW STUDY ON THE LASER TECHNOLOGY AND APPLICATIONS IN THE MECHANICAL AND MACHINE MANUFACTURING INDUSTRY","authors":"M. Chau","doi":"10.26480/jmerd.05.2019.16.20","DOIUrl":"https://doi.org/10.26480/jmerd.05.2019.16.20","url":null,"abstract":"Laser is considered one of the most influential inventions in the twentieth century and laser technology has been contributing in many areas of life. Today, in any field of manufacturing, laser technology also presents value and brings a range of specific benefits to the field such as machine manufacturing and mechanical tools. Thanks to the cutting edge cleaning ability, delicate welding lines, strong etching strokes, high power operation, accurate distance measurement capability, laser technology has gradually conquered and dominated the mechanical market, especially in the field of material handling, metal parts. Using lasers to cut metal creates highly detailed and continuous details, lines, shapes, patterns ... that open new avenues for the mechanical and machine-building industry. Using laser engraving machines, it will process complex and sophisticated details, saving time and manpower costs. High processing speed, smooth cutting surface and easy programming are the advantages that laser cutting technology offers to this industry. Lasers can be cut on different sheet metal or tubular surfaces at extremely fast speeds on tools, machine parts and even small-sized cutting workpieces. This paper will present an overview of laser technology and its common applications in the mechanical and machine-building industry. The analysis and evaluation in this paper will provide an update on the level of development of laser technology in the current industry age 4.0. In addition, it is a common picture and achievements of the machine manufacturing industry achieved with the support of \"Light Amplification by Stimulated Emission of Radiation\".","PeriodicalId":16153,"journal":{"name":"Journal of Mechanical Engineering Research and Developments","volume":"29 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86481258","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}
引用次数: 12
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