scholarly journals Kinematic and Dynamic Response of a Novel Engine Mechanism Design Driven by an Oscillation Arm

2020 ◽  
Vol 10 (8) ◽  
pp. 2733
Author(s):  
Călin Itu ◽  
Maria-Luminiţa Scutaru ◽  
Cătălin Iulian Pruncu ◽  
Radu Muntean
Keyword(s):  
Stroke Volume ◽  
Dynamic Response ◽  
Mechanism Design ◽  
Compression Ratio ◽  
Power Parameter ◽  
Higher Power ◽  
Additional Improvement ◽  
Piston Stroke ◽  
Rate Of Success ◽  
Engine Power

The goal of this paper is to highlight the advantage fulfilled by a novel engine mechanism, the concept of which is based on an oscillating arm relative to the classical engine mechanism. Further, the results of this paper demonstrate the benefits of a novel type of mechanism and the major advantages in terms of functioning parameters of an engine. Their performances highly depend on the joint positions of the oscillating arm. The increases in the functional performances rate of success (i.e., piston stroke, volume of the combustion chamber or compression ratio) enable a superior engine power parameter (higher power, torque) and bring some additional improvement on the eco parameters of the engine related to consumption, emission, etc.

Design and Preliminary Testing of a Prototype Thermophotovoltaic System

2003 ◽  
Author(s):  
Chris J. Astle ◽  
Gary J. Kovacik ◽  
Ted R. Heidrick
Keyword(s):  
The Sun ◽  
Solar Pv ◽  
Pv System ◽  
Solar Photovoltaics ◽  
Compact Size ◽  
Higher Power ◽  
Close Proximity ◽  
Solar Pv System ◽  
Additional Improvement ◽  
Power Densities

Thermophotovoltaics (TPV) is technology similar to conventional solar photovoltaics, which have been in existence for over 50 years. The main difference between traditional solar photovoltaics and TPV is that, instead of the sun, an “emitter” is used to produce light, which is then converted into electricity by the TPV system. This emitter is heated via combustion or some other method until photons are ejected. Although the light utilized in the TPV system is not as energetic as that from the sun, the fact that the TPV cells can be placed in close proximity to the source (compared with the distance to the sun) increases the intensity of the light received by the cells. This results in a higher power production density than is possible with traditional solar photovoltaic systems. One estimate of maximum achievable output power density for TPV systems is 5W/cm2, approximately 500 times that of a traditional solar PV system. Researchers in this field have already demonstrated power densities of 1.5W/cm2. Other attractions of TPV systems include fuel versatility, compact size, silent sun-independent operation, and low maintenance costs. A TPV test station has been assembled at the Alberta Research Council in Canada. A general overview of the background technology and system components will be presented, as well as preliminary experimental results. Areas that require additional improvement in order to increase system efficiency will also be addressed.

scholarly journals Influence of combustion chamber geometry on performance and emissions of diesel engine Vikyno RV125-2

2015 ◽  
Vol 18 (1) ◽  
pp. 102-111
Author(s):  
Khai Le Duy Nguyen ◽  
Hung Dac Khanh Nguyen
Keyword(s):  
Diesel Engine ◽  
Combustion Chamber ◽  
Compression Ratio ◽  
Direct Injection ◽  
Soot Concentration ◽  
Research Results ◽  
Direct Injection Diesel Engine ◽  
Piston Bowl ◽  
Performance And Emissions ◽  
Engine Power

This paper presents a research on the influence of combustion chamber geometry on performance and emissions of direct injection diesel engine VIKYNO RV125-2 using threedimensional CFD code KIVA-3V. In this study, the piston bowl depth (pip-height), bottom bowl diameter and bowl diameter are changed while the engine compression ratio is still kept. Research results indicate that increased bowl diameter works best. Specifically, when the bowl diameter changes from 3.98cm to 4.7cm, the engine power is increased 22.6%, while the concentration of NOx is reduced 0.85%. However soot concentration will increase 45.83%.

scholarly journals A predictive control method for reducing power backflow in DC/AC matrix converter

2021 ◽  
Vol 2087 (1) ◽  
pp. 012041
Author(s):  
Zhipeng Xia ◽  
Ping Jin ◽  
Ling Chang
Keyword(s):  
Dynamic Response ◽  
Predictive Control ◽  
Control Method ◽  
Reducing Power ◽  
Matrix Converter ◽  
Voltage Source ◽  
Attractive Alternative ◽  
Loosely Coupled ◽  
Higher Power ◽  
Optimal Function

Abstract In recent years, DC/AC matrix converter with higher power density have become an attractive alternative to traditional voltage source converters. The traditional PI control has been employed to achieve accurate control, but its dynamic response and stability need to be improved. In this paper, a model predictive control (MPC) with reducing power backflow is introduced in an isolated DC/AC matrix converter with a loosely coupled high-frequency transformer (LCHFT). Prediction model and optimal function model are established to improve the dynamic response of the system and reduce the power backflow.

Experimental Research on Dynamic Response for RC Column Subjected to Impact Loading

2010 ◽  
Vol 168-170 ◽  
pp. 319-322
Author(s):  
He Su ◽  
Yu Min Zhang ◽  
You Po Su
Keyword(s):  
Dynamic Response ◽  
Axial Compression ◽  
Compression Ratio ◽  
Shear Failure ◽  
Shear Mode ◽  
Reinforced Concrete Column ◽  
Axial Compression Ratio ◽  
Flexural Failure ◽  
Axial Forces ◽  
Peak Value

In order to analyze the influences of axial compression ratio and loading speed to the dynamic response and failure mode of RC columns subjected to blast loading, the collapse test for 6 reinforced concrete column models were conducted. Results show that there are three kinds of failure types: shear failure, flexural failure, flexural-shear failure. It tends to failure in shear mode when compression ratio is 0, and tends to failure in flexural or in flexural-shear mode when compression ratio is 0.5 and 0.25 respectively. The peak value of the exerted load and end moment will increase with the increasing of axial compression ratio in the first stage (approximately when compression ratio is less than 0.25) and then will decrease. The peak value of extra axial forces will decrease with the increasing of axial compression ratio.

scholarly journals Study on cold starting performance of a low compression ratio diesel engine by using intake flame preheating

2020 ◽  
Vol 24 (1 Part A) ◽  
pp. 51-62 ◽  
Author(s):  
Chao Zhang ◽  
Bolan Liu ◽  
Jingchao Hu ◽  
Xiyang Yu ◽  
Xiaogang Wang
Keyword(s):  
Diesel Engine ◽  
Power Density ◽  
Compression Ratio ◽  
Fuel Injection ◽  
Heating System ◽  
Turbocharged Diesel Engine ◽  
Cold Starting ◽  
Basic Performance ◽  
Safety Consideration ◽  
Engine Power

Power density improvement is one the main techniques for engine thermal efficiency promotion. For turbocharged Diesel engine, low compression ratio in normally adopted for safety consideration under high power density operation. However, low compression ratio tends to lead cold starting problem. In this study, the influences factors and performances of a 10-cylinder turbocharged Diesel engine was investigated. An intake flame preheating model was built and validated by series of bench tests. The optimization of starting parameters and flame heating was conducted eventually. Based on the study, the basic performance flame pre-heating system under different conditions was disclosed. The cold starting boundary parameters of the Diesel engine was found. Moreover, the best starting fuel injection parameters were acquired. The research is beneficial for Diesel engine power density promotion based on cold starting ability

Key Parameters Simulation and Design of Natural Gas Engine Based on Diesel

2013 ◽  
Vol 318 ◽  
pp. 584-587
Author(s):  
Meng Xiang Liu ◽  
Xiang Ling Liu ◽  
Jin Ke Gong ◽  
Fei Yang ◽  
Jian Bin Chen
Keyword(s):  
Natural Gas ◽  
Compression Ratio ◽  
Valve Timing ◽  
Gas Engine ◽  
Natural Gas Engine ◽  
Exhaust Temperature ◽  
Rise Rate ◽  
Research Achievement ◽  
Maximum Rise ◽  
Engine Power

In the paper, the natural gas engine (NGE)model based on AVL BOOST software is built and simulated. The simulation value and experiment value coincide, showing that the NGE model is correct and reasonable. On this basis, the model has been used to analyze the effect of the key parameters, such as compression ratio, ignition advance angle, valve timing, supercharging ratio on the engine power, maximum combustion pressure, exhaust temperature, the maximum rise rate of pressure. Combined with the relevant theories of engine, the value ranges of the key parameters can be designed. The research achievement is valuable in the development and optimization matching of the NGE.

A Computational Study on Performance, Combustion and Emissions Characteristics of a Hydrogen-Fueled Internal Combustion Engine

2009 ◽  
Author(s):  
Shravan K. Vudumu ◽  
Umit O. Koylu
Keyword(s):  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Computational Study ◽  
Internal Combustion ◽  
Nox Emissions ◽  
Combustion Engines ◽  
Hydrogen Fuel ◽  
Operational Conditions ◽  
Higher Power ◽  
Engine Power

Hydrogen is an alternative fuel that is considered to be one of the viable solutions to the increasing demands of clean and secure energy. Internal combustion engines fueled by hydrogen have the potential for higher power and efficiency with lower emissions when compared to gasoline. In the present study, advanced engine simulations were used to study the performance, combustion and emission characteristics of a hydrogen-fueled engine. Hydrogen fuel-specific combustion models were used to account for the distinctive characteristics of hydrogen combustion when compared to that of gasoline. The simulation results matched well with the already-published experimental data under similar engine operational conditions. NOx emissions were found to increase drastically after an equivalence ratio of 0.5 due to high combustion temperatures. EGR was found to be an effective way to reduce NOx emissions but compromised engine power and efficiency.

Physical Fitness and Resting EEG in Children With Attention Deficit Hyperactivity Disorder

2015 ◽  
Vol 29 (1) ◽  
pp. 26-32 ◽  
Author(s):  
Ching-Wen Huang ◽  
Chung-Ju Huang ◽  
Chiao-Ling Hung ◽  
Chia-Hao Shih ◽  
Tsung-Min Hung
Keyword(s):  
Attention Deficit Hyperactivity Disorder ◽  
Physical Fitness ◽  
Attention Deficit ◽  
Resting State ◽  
Self Control ◽  
Children With Adhd ◽  
Hyperactivity Disorder ◽  
Higher Power ◽  
Eyes Open ◽  
The Relationship

Children with attention deficit hyperactivity disorder (ADHD) are characterized by a deviant pattern of brain oscillations during resting state, particularly elevated theta power and increased theta/alpha and theta/beta ratios that are related to cognitive functioning. Physical fitness has been found beneficial to cognitive performance in a wide age population. The purpose of the present study was to investigate the relationship between physical fitness and resting-state electroencephalographic (EEG) oscillations in children with ADHD. EEG was recorded during eyes-open resting for 28 children (23 boys and 5 girls, 8.66 ± 1.10 years) with ADHD, and a battery of physical fitness assessments including flexibility, muscular endurance, power, and agility tests were administered. The results indicated that ADHD children with higher power fitness exhibited a smaller theta/alpha ratio than those with lower power fitness. These findings suggest that power fitness may be associated with improved attentional self-control in children with ADHD.

Human pilot dynamic response in flight and simulator.

1958 ◽  
Author(s):  
Edward Seckel ◽  
Ian A. M. Hall ◽  
Duane T. McRuer ◽  
David H. Weir
Keyword(s):  
Dynamic Response
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