International Journal of Mechanical Engineering and Applications最新文献

{"title":"Applicability of Source Water Source Heat Pump System in Hot Summer and Warm Winter Area","authors":"W. Hu","doi":"10.11648/j.ijmea.20190705.11","DOIUrl":"https://doi.org/10.11648/j.ijmea.20190705.11","url":null,"abstract":"Water source heat pump with relatively stable surface water as heat transfer medium is a new type of energy-saving and temperature-regulating equipment. Its refrigeration and heating coefficients are 3.5-4.5 high. Water source heat pump has been widely used in refrigeration and heating of buildings in many foreign countries as an important energy-saving equipment. The number of water source heat pump energy stations has increased by 10% annually. The traditional coal pans used in large greenhouses in China often have some problems, such as low thermal efficiency, high energy consumption, high pollution and difficult cooling in summer. It is very helpful to use water source heat pump technology reasonably to solve these problems. In this paper, the water source heat pump air conditioning system is used in public places for experimental testing and research. The operation performance of the water source heat pump energy station is studied through experimental tests, which can provide reference for the popularization and application of the technology in hot summer and warm winter areas. The research contents of this subject are as follows: Under the rated operating conditions of the water source heat pump air conditioning system; the operation performance of the heating system is analyzed; Understanding and mastering the operation performance of water source heat pump air conditioning system, and comprehensively analyzing the stability and energy efficiency ratio of the system; The main problem to be solved is that it can not only ensure the operation cost unchanged or even reduce, but also improve the heating efficiency of water source heat pump air conditioning system.","PeriodicalId":398842,"journal":{"name":"International Journal of Mechanical Engineering and Applications","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129714170","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 and Application of Insulator Detection Robot System for UHVDC Transmission Line","authors":"Xueneng Huang, Xie Yuwen, Ma Chongjie, Tan Jinpeng, D. Qiu, Youneng Wu, Fang Su, Lu Yitao, YongJiang Lin, Liu Xianning","doi":"10.11648/J.IJMEA.20190704.13","DOIUrl":"https://doi.org/10.11648/J.IJMEA.20190704.13","url":null,"abstract":"In recent years, with the vigorous construction of the ultra-high voltage grid, the line operating voltage level has become higher and higher. In order to ensure the safe operation of the transmission line, the line insulator string has a length of several tens of meters, and traditional manual testing has been unable to meet the requirements. With the continuous maturity of wireless communication technology, electromagnetic compatibility technology, sensor technology and other comprehensive technologies, it is necessary to develop an insulator string detection robot to replace artificial insulator detection work on UHV transmission lines. By means of wireless sensor communication technology, electromagnetic compatibility technology, video image technology and many other technologies, the insulator detection robot designed in this paper has realized automatic detection of zero resistance value of insulator of UHV transmission line. In addition, the real-time monitoring of insulator resistance value can be carried out through wireless communication to achieve the purpose of timely alarm. In addition, the robot's motion status and the insulator's field status can be observed in real time through video image acquisition. The insulator detection robot designed in this paper realizes the automatic detection of the zero value of insulator of the UHV DC transmission line. It can adapt to the UHV AC DC transmission line with different voltage levels by changing the length of the climbing arm, and at the same time adapt to the climbing detection of the string insulator of tension tower and the vertical insulator of the straight tower. The problem that the insulator string of the UHVDC transmission line can not be automatically detected by electric charge has been solved. It greatly improves the efficiency of insulator detection and the automation level of power transportation maintenance, reduces the cost of human transportation, and creates higher economic and social benefits.","PeriodicalId":398842,"journal":{"name":"International Journal of Mechanical Engineering and Applications","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115159396","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":"Influence of Different Heat Input on Submerged Arc Welded Joints of High Strength Low Alloy Steel SX780CF","authors":"H. Li, Xian-long Hu, Zhixian Peng, Youlong Zhou","doi":"10.11648/J.IJMEA.20190704.12","DOIUrl":"https://doi.org/10.11648/J.IJMEA.20190704.12","url":null,"abstract":"SX780CF is a new type domestic high strength low alloy (HSLA) steel with tensile strength of 800 MPa, which was used firstly for pressure pipes in the hydropower unit. In order to improve the efficiency, SX780CF is generally welded by submerged arc welding (SAW), and a kind of special intelligent welding machine for large-scale pressure steel pipe was adopted, which can realize intelligent mechanized grouping and automatic welding in tunnel. In this paper, two different levels of heat input were used to weld SX780CF. The weldability of two joints was analyzed, the mechanical properties of the joints were measured, and the hardness distribution of the joints was tested. Meanwhile, the microstructure was observed. The results show that the properties of these joints welded by two different levels of heat input could satisfy the demand of the GB 50766 -2012 standard. The mechanical properties of the weld joint with larger heat input were slightly higher than those with smaller heat input. The hardened tendency of SX780CF is small, however, the steel with the thickness of 60 mm needs to be preheated at more than 112°C. Comprehensive comparison shows that the submerged arc welding method with larger heat input has better efficiency and cost advantage, and it is worthy of promotion in hydropower project.","PeriodicalId":398842,"journal":{"name":"International Journal of Mechanical Engineering and Applications","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123410760","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":"A Friction Control Strategy for Shock Isolation","authors":"Mohd. Ismail, N. Ferguson","doi":"10.11648/J.IJMEA.20190703.12","DOIUrl":"https://doi.org/10.11648/J.IJMEA.20190703.12","url":null,"abstract":"A control strategy is presented incorporating friction which can be adapted within a cycle of vibration. During base shock input, the friction is switched on and off based on specified response parameters. The predicted response of a semi active system is compared with that of a passive isolation system. The strategy is shown to produce an improved displacement reduction and a smaller maximum displacement compared to the base input; a result which cannot be obtained with a typical passive system. The models are then validated using an experimental rig, representing a two degree of freedom system, having an electromagnet to switch on and off friction via the control logic. Good agreement is obtained in addition to identifying optimum parameter choices.","PeriodicalId":398842,"journal":{"name":"International Journal of Mechanical Engineering and Applications","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114757638","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":"Parametric Study of Drivetrain Dynamics of a Wind Turbine Using the Multibody Dynamics","authors":"W. Shi, D. Ning, Zhe Ma, Nian-xin Ren, Hyunchul Park","doi":"10.11648/J.IJMEA.20190703.11","DOIUrl":"https://doi.org/10.11648/J.IJMEA.20190703.11","url":null,"abstract":"Wind energy has become one of the most cost-effective and environmental friendly renewable energy resources among all exploited renewable energy. However, the failure of gearbox contributes most of the downtime for wind turbine system. Dynamic properties of drivetrain, including gearbox should be investigated in detail further. In present paper, a mathematical model for a horizontal axis wind turbine drivetrain was developed using the torsional multibody dynamic model. The drivetrain in this study consisted of a low-speed planetary gear stage (three identical planets with spur teeth, sun and fixed ring gears) and two high-speed spur gear stages. This typical arrangement has been commonly used in the wind turbine industry. Based on this model, this paper aims to investigate the influence of drivetrain parameters on the dynamic response of the wind turbine. The dynamic responses of the turbine with different rotor inertia and generator inertia are compared. Then the difference due to changing of the shaft stiffness is also investigated during and after the transient condition. This parametric study shows that lower rotor inertia and generator inertia could lead to more oscillations.","PeriodicalId":398842,"journal":{"name":"International Journal of Mechanical Engineering and Applications","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131539805","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 Solar Powered and Fatigue Durable Quadcopter","authors":"Yingbo Xu, Qianfeng Wan, Mwanza Taipa Raymond, Gang Lu, Xianghu Zeng","doi":"10.11648/J.IJMEA.20190702.14","DOIUrl":"https://doi.org/10.11648/J.IJMEA.20190702.14","url":null,"abstract":"This paper features a new concept design of mini-quadcopter consisting of two types of power source systems. The solar type of power source and rechargeable lithium battery type of power source systems. The quadcopter design introduced showcases the extensive usefulness of solar cells on aircrafts. The title is “SPFD quadcopter”, the SPFD stand for “solar powered fatigue durable” quadcopter. the quadcopter in question is designed to be powered by 40 solar thin film cells rated at 1.5v per panel. A fatigue analysis is conducted in its arm structures that offer support to the four mounted brushless motors responsible for driving the propellers that produce sufficient thrust to provide lift. By use of the “ANSYS” designing and simulating program, the carried out analysis shows the level of deformation in the arms due to the weight of the entire craft which tends to rest on the arms when the quadcopter is in flight. A fatigue structure analysis was considered necessary, to take appropriate precautions in both early stages of design and choice of material, to prevent premature structure failure in the field. Our objective of this paper is generally to show case the use of flexible solar cells as the source of power for providing power to the motors with the capability of charging the lithium battery during flight when being operated in battery mode. this new type of UAV can be used for military and civilian needs, surveillance and even space operations such as being set as a satellite to provide signal for internet back to earth.","PeriodicalId":398842,"journal":{"name":"International Journal of Mechanical Engineering and Applications","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131947470","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":"Fracture Toughness Testing and Prediction for Ceramic Materials Using in Large-Flow-Rate Emulsion Pumps","authors":"Ran Li, Wenshu Wei, Shoubin Li, Yinshui Liu, Hao Liu, Huigang Wu, Wen Wang, Jian-Ding Ye, Chenjin Tian, Da-lin Wang, M. Wu, Jiankai Zhang","doi":"10.11648/j.ijmea.20190702.12","DOIUrl":"https://doi.org/10.11648/j.ijmea.20190702.12","url":null,"abstract":"Fracture toughness (KIC) tests have been carried out on single edge precracked beam specimens with dimensions in accordance with ISO15732 requirements for two types of zirconia and one type of alumina, i.e. ZrO2 -1, ZrO2 -2 and Al2O3. Experimental determinations of KIC for the two zirconia and one alumina materials are 12.18 MPa•m1/2, 16.35 MPa•m1/2 and 4.99 MPa•m1/2, respectively. The median rank method is used to calculate the probability of fracture, F(KIC) of the three cermaic materials for representing the experimental results. The SEM analysis on fracture surfaces of ZrO2-1 materials is carried out, which indicates the fracture in ZrO2 -1 material occurred at the interior of the grain associated with interior stress distribution with principal components of ZrO2 and SiO2. Th extended finite element method (XFEM), based on the linear elastic fracture mechanics in conjuciton with a bilinear traction-separation damage law, is used to simulate the progressive crack growth process in the SEPB specimens. The XFEM predicted KIC results are compared with the corresponding experimental data. The XFEM approach overpredicts the KIC values, from 10.4% to 25.6%, for the three ceramic materials. The possible reasons, in the aspect of loading conditions and contact assumptions, for the difference between the predicted and tested results are also discussed.","PeriodicalId":398842,"journal":{"name":"International Journal of Mechanical Engineering and Applications","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116167136","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 the Hydrostatic Thrust Spherical Bearing with Restrictors (Fitted Type)","authors":"Ahmad Waguih Elescandarany","doi":"10.11648/J.IJMEA.20190702.11","DOIUrl":"https://doi.org/10.11648/J.IJMEA.20190702.11","url":null,"abstract":"The hydrostatic bearings are broadly observed in industrial applications owing to their potential characteristics of low running friction, high load-carrying capacity, high stiffness and small viscous dissipation. Spherical bearings have advantages over other configurations of bearings because of their self-aligning property and also their capacity to accept both radial and thrust loads. Operation of the spherical bearings is unaffected by angular miss-alignment. They are mainly used in machine tools, precision measuring instruments, hydraulic piston pumps and motors, gyroscope gimbals, telescopes, radar tracking units, air craft engines and rotary drum of centrifugal separator for enriched uranium. The main objective of this part of study is to handle the fitted bearing design taking into consideration the combined effects of rotational inertia, surface roughness and the fluid film viscosity variability. The mathematical expressions derived in part 2 for this type of bearings with its different configurations (with and without recess; hemispherical and partial hemispherical seats) have been used in the detailed bearing design. Improving the previous design through developing some mathematical expressions, a new conception is adopted to reveal the bearing consistency showing how the fluid flow rate pulsation or intermittent could be prevented. The detailed design procedures show the advantages of this method to get the central pressure ratio mathematically through maximizing the flow rate with minimizing the supply pressure which means minimum pump power to get maximum discharge. This design showed very high mean static stiffness of all the bearing configurations and an acceptable temperature rise for a heavy duty bearing without the need to a use a cooling system.","PeriodicalId":398842,"journal":{"name":"International Journal of Mechanical Engineering and Applications","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126866569","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":"Modelling of the Nnormobaric and Hyperbaric Facilities Ventilation","authors":"R. Kłos","doi":"10.11648/J.IJMEA.20190701.14","DOIUrl":"https://doi.org/10.11648/J.IJMEA.20190701.14","url":null,"abstract":"This paper is the result of many work and research programs. During the execution of the projects, it was proposed a new mathematical model of the process of ventilation of a semi-closed rebreather. Its validation required making a special simulator of gas exchange in the breathing process. Use of the device made experimental validation of the proposed model possible. This model has been adjusted to the process of ventilation in hyperbaric chambers. The validation process required developing a new type of carbon dioxide emission simulator. The generalization of the adopted method for the submarine ventilation process was only an obvious consequence of earlier considerations. However, the validation process required to undertake extensive research on a real object, which confirmed the validity of the modelling method adopted. The research on ventilation of the mining excavation constituted the validation of the adopted research approach. In typical residential and public buildings, similar methods have been used relatively recently. In general, they involve air-conditioning of the sealed buildings. This entails the need to regenerate the respiratory atmosphere inside, making them similar to military facilities. Methods of protection against contamination can be used with regard to atmospheric pollution, especially in the work environment. As in the case of military facilities, the methods of modelling ventilation in standard and hyperbaric objects described here would allow developing more accurate methods to design and use ventilation and air-conditioning systems in buildings.","PeriodicalId":398842,"journal":{"name":"International Journal of Mechanical Engineering and Applications","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116977690","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":"Magnetically Levitated Linear Drive with Repulsive Magnetic Guidance","authors":"Markus Raab, Bernd Gundelsweiler, W. Schinköthe","doi":"10.11648/J.IJMEA.20190701.13","DOIUrl":"https://doi.org/10.11648/J.IJMEA.20190701.13","url":null,"abstract":"Linear direct drives are often used when high performance is required, because of their high dynamic and their good position accuracy. Usually direct drives are used with linear rolling guidance. In clean room and vacuum applications linear rolling guidance cannot be used as particles can be cause problems. In this paper a magnetically levitated linear direct drive with a combination of repulsive permanent magnet stabilization and Lorentz force based stabilization is presented. With the joint use of magnet fields high dynamic can be achieved in combination with a cost efficient hardware. Due to the use of repulsive permanent magnet forces, it is possible to levitate an armature with nearly no power dissipation. An ad-hoc control reduces the power dissipation to a value less than 10 mW.","PeriodicalId":398842,"journal":{"name":"International Journal of Mechanical Engineering and Applications","volume":"286 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131911633","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}