-
A Study on Linear Generator Characteristics in Free Piston Engine
Ly Vinh Dat
,
Nguyen Thai Hoc
Issue: Volume 7, Issue 3, September 2021
Pages: 78-84
Received: Aug. 21, 2021
Accepted: Aug. 25, 2021
Published: Aug. 31, 2021
DOI:
10.11648/j.ijtet.20210703.13
Downloads:
Views:
Abstract: The linear generator (LG) is integrated into a system that called the free piston linear generator (FPLG). In recent year, free piston engine that is studied by many researchers, has some advantages. Therefore, the application of the line generator in free piston for converting the chemical energy to electrical energy that can be used for plug-in hybrids to extend the range of operations as an alternative energy converter. Therefore, the optimizing of linear generator performance be able to significantly reduce the vehicle's fuel consumption. The parameters in permanent magnet linear electric machine (PMLEM) are designed by Maxwell software and the optimal parameters is carried out via the flux density. To achieve this goal, a linear generator in free piston engine with a flat structure and quasi-Halbach array flux structure was proposed. The simulation of linear generator is performed based on the speed ranges in the New European Driving Cycle (NEDC) for a mid-size car. In the study, a linear electrical machine (LEM) is designed by Maxwell software with translator that has various diameters. The results show that the suitable parameters for stator and rotor about 7.7 mm and 14 mm, respectively. Because the flux density for this design’s stator and rotor yoke avoids saturation state and generates the highest electrical output compared to the other states. Besides, the paper also examined the power output at different frequencies from 15 Hz to 50 Hz, corresponds to a velocity amplitude of 3.6 m/s to 12 m/s. The simulation result shows that the frequencies from 15Hz to 30 Hz with 4.8 m/s to 7.2 m/s (1200 rpm to 2100 rpm), respectively meets engine speed operation ranges in hybrid vehicle and these frequencies produce the power output that increases considerably about 7.5 kW at 30 Hz.
Abstract: The linear generator (LG) is integrated into a system that called the free piston linear generator (FPLG). In recent year, free piston engine that is studied by many researchers, has some advantages. Therefore, the application of the line generator in free piston for converting the chemical energy to electrical energy that can be used for plug-in h...
Show More
-
Review on Urban Transportation System and Its Adverse Impacts to Public Health of the Cities
Vo Minh Phuc
,
Vo Trong Cang
Issue: Volume 7, Issue 1, March 2021
Pages: 24-28
Received: Sep. 26, 2020
Accepted: Nov. 21, 2020
Published: Mar. 26, 2021
DOI:
10.11648/j.ijtet.20210701.14
Downloads:
Views:
Abstract: The main research objective is creating the knowledgebase on transport and urban development and their adverse impacts to public health of big cities’ citizen. This research is a flatform from which future studies could be conducted with the purposes to improve urbanization and health-related issues toward healthy cities and sustainable urban development. The literature review research method is applied throughout the study process to review and summarize on: (1) the legal documents on urban planning and development, including transportation, environmental related-aspects; (2) scientific studies on urban planning and development, urban planning - transport - public health relationship, public health contribution to sustainable development, and (3) news and articles from media, newspaper about the current situation of urban planning, traffic, health issues and changes in related policies, etc. Main findings of the study: (1) listing out the major negative health effects related to transport and urban planning, such as: injuries and accidents are main causes leading to urban mortality (especially in Asia) and illness realated to pollutants releasing from traffic activities; and (2) introduction some public health improvement applying planning-related measures: Healthy Cities Program (HCP) and Healthy Urban Planning (HUP) by WHO, KonSULT’s policy measures analysis in term of Health effects.
Abstract: The main research objective is creating the knowledgebase on transport and urban development and their adverse impacts to public health of big cities’ citizen. This research is a flatform from which future studies could be conducted with the purposes to improve urbanization and health-related issues toward healthy cities and sustainable urban devel...
Show More
-
Evaluation of Applying Various High Voltage Levels to Improve Fuel Injector Response Time on Gasoline Engines
Phan Nguyen Qui Tam
,
Do Van Dung
,
Dinh Cao Tri
Issue: Volume 7, Issue 1, March 2021
Pages: 19-23
Received: Nov. 07, 2020
Accepted: Feb. 27, 2021
Published: Mar. 26, 2021
DOI:
10.11648/j.ijtet.20210701.13
Downloads:
Views:
Abstract: This paper presents the effect of various high applied voltage levels on the responsiveness of fuel injectors on gasoline engines. During operation, the inductance in the injector changes at a certain value because of the change of magnetic permeability, which is the result of the needle lifting process, directly affects the curve of the current in the needle. On the other side, the amperage in the injector is hampered by another amperage produced by the phenomenon of self-inductance, leading the current in the injector increase slowly resulting in the needle lifting will be delayed. Normally, there are two ways to increase the response time that including the improvement of fuel injector shape and injection control method. But in this paper, to improve the response time without changing either the structure or the control method of the injector, the authors conduct research on increasing the operating voltage level in order to reduce the dead time of the needle. In particular, a mathematical description of the fuel injector amperage will be built based on two different inductance values, then some experiments are practiced to evaluate the response time of the fuel injector. Experimental results in the range of 12V to 30V indicated that the sensitivity of the injector was significantly improved.
Abstract: This paper presents the effect of various high applied voltage levels on the responsiveness of fuel injectors on gasoline engines. During operation, the inductance in the injector changes at a certain value because of the change of magnetic permeability, which is the result of the needle lifting process, directly affects the curve of the current in...
Show More
-
Analysis of Oscillation of Propulsion System on Hovercraft - Theoretical Framework and Review
Issue: Volume 6, Issue 4, December 2020
Pages: 128-132
Received: Aug. 02, 2020
Accepted: Sep. 09, 2020
Published: Dec. 22, 2020
DOI:
10.11648/j.ijtet.20200604.14
Downloads:
Views:
Abstract: With flexible usability, able to operate both on water and land, hovercraft has a long history of development and is widely used in many countries around the world. In this research, we focus on solving the problem of isolation oscillates when a machine - placed on an isolator - operates the pinwheel to create thrust momentum for hovercraft movements. The main content of the author’s master degree research is to study the oscillator system integrated in the engine structure to significantly reduce the vibration from the main engine and the propeller of the air cushion ship. The study focused on building a calculation model to find the main vibration characteristics of the propulsion system - motor - motor support structure integrated with damping system. Main objective is finding out the parameter values: transmission characteristics, specific frequencies of the air-cushion engine structure and damping system of supporting structure which are able to withstand the best vibration isolation. Based on reviewed literature, simulations and real-world tests (using CALFEM and following simulation models) are being performed to determine the optimal technology parameters. The findings and results continue to contribute to the improvement of engine technology in particular and seaplane engineering technology in general as required by standards and regulations.
Abstract: With flexible usability, able to operate both on water and land, hovercraft has a long history of development and is widely used in many countries around the world. In this research, we focus on solving the problem of isolation oscillates when a machine - placed on an isolator - operates the pinwheel to create thrust momentum for hovercraft movemen...
Show More
-
Combined Teaching Methods of Technical Drawing in Shipbuilding Engineering
Tran Van Tao
,
Vo Trong Cang
Issue: Volume 6, Issue 4, December 2020
Pages: 123-127
Received: Nov. 12, 2020
Accepted: Dec. 05, 2020
Published: Dec. 11, 2020
DOI:
10.11648/j.ijtet.20200604.13
Downloads:
Views:
Abstract: Combining the teaching practice and academic analysis, we explored and studied various teaching methods of "Technical Drawing" to stimulate students' interest in learning and to improve the quality of teaching. It mainly includes a good teacher-student relationship, a combination of various teaching methods, good first-lesson, intensive teaching and process evaluation. According to the characteristics of students and the teaching content, the teaching methods can be scientifically set up to achieve good teaching quality and training results. The initial application results are: use in combination with audio-visual equipment such as 3D images on a computer; perform physical models with a miniature scale from on-paper drawings and especially experience group activities during student practice hours. Through this study, at the Ho Chi Minh city University of Technology, VNU-HCM, faculty of Transportation Engineering, we have tried to find ways to alleviate the difficulties, stimulate students' interest in learning in two directions: 1) enrich the imagination of 3D space and 2) increase the introduction of the production knowledge in the most condensed way. The ultimate goal is to improve teaching efficiency in this subject. On the other hand, the products, models, created by students from the subject are also the good models for the next courses.
Abstract: Combining the teaching practice and academic analysis, we explored and studied various teaching methods of "Technical Drawing" to stimulate students' interest in learning and to improve the quality of teaching. It mainly includes a good teacher-student relationship, a combination of various teaching methods, good first-lesson, intensive teaching an...
Show More
-
The Effect of the Change in the Position of Load on the Inclination Angle of Floating Crane
Tran Van Tao
,
Nguyen Chien Luy
Issue: Volume 6, Issue 4, December 2020
Pages: 118-122
Received: Nov. 06, 2020
Accepted: Dec. 05, 2020
Published: Dec. 11, 2020
DOI:
10.11648/j.ijtet.20200604.12
Downloads:
Views:
Abstract: Floating cranes are equipment used for the transport of goods in the ports of Viet Nam. Some of the floating cranes such as the equipment to renovate river cages are also widely used in Vietnam. During operation, the balance of the floating cranes differs from that of the land cranes because of changes in the volume displacement. Besides, the center of the entire structure will vary depending on the location of the goods. For floating cranes the research document is often interested in statically and dynamically stabilizing. Static stability in idle or under load condition is no longer considered by checking whether the stabilization moment is greater than the overturning moment. The dynamic stability was the static balance of the crane is disturbed and behave like certain periodic or unexpected movements on the way to a different balancing position. However, this article refers to the effect of the lifting process on the static equilibrium of floating cranes. The stability of the floating crane is differ from normal ship especially when it is lifting cargo or goods, when the hangging cargo changes its position that will effect to the position of the gavity center of the total weight. In this paper we would like to show the way to calculate hydrostatic and stability of floating crane, especially the changing of inclination angle (heeling and pitching angle) as the hangging goods change its position.
Abstract: Floating cranes are equipment used for the transport of goods in the ports of Viet Nam. Some of the floating cranes such as the equipment to renovate river cages are also widely used in Vietnam. During operation, the balance of the floating cranes differs from that of the land cranes because of changes in the volume displacement. Besides, the cente...
Show More