scholarly journals Comparative evaluation of dynamics and fuel efficiency indicators of the car with robotic stepped transmission under condition of different diameters of engine cylinders

2021 ◽  
pp. 35-40
Author(s):  
Hustav Hudz ◽  
Mykhailo Нlobchak ◽  
Roman Pelo ◽  
Oleg Kotsjumbas
Keyword(s):  
Comparative Evaluation ◽  
Fuel Efficiency ◽  
Work Conditions ◽  
Matlab Simulink ◽  
Automotive Vehicle ◽  
Working Volume ◽  
Vehicle Category ◽  
Different Diameters ◽  
Cylinder Liners ◽  
Efficiency Indicators

Problem. Repair dimensions method regulates increment of cylinders by the means of mechanical treatment, which leads to increasing of working volume of the engine. This will cause a change of dynamics and fuel-efficiensy indicators of the car with the certain type of transmission. Goal. The goal is to comparatively evaluate dynamism and fuel-efficiency of automotive vehicle category N2 with two options of engines, which have nominal and repair cylinder sizes. The riding cycle of the cars with robotic stepped gearbox was researched, that is without breaking of force stream while switching gears. Methology. Imitative simulation of cars riding cycle, according to standard, was conducted with the help of Matlab Simulink software. Because of the fact that mathematical model of cars movement during mentioned cycle is based on elementary dependencies, for its realization the only basics avialable blocks of the sofware package were used. The flowchart is given in the paper. Results. Simulation of riding cycle of N2 – category automotive vehicle with robotic gearbox was conducted at full engine’s capacity while running-up. Obtained results have shown that engines with repairment sizes have advantage in dynamism indicators, engines with nominal cylinder sizes have advantages in fuel-efficiency. Originality. For obtaining of comparative evaluation of dynamics and fuel-efficiency indicators of the car with robotic gearbox with different engines, the imitation simulation of riding cycle, according to standarts, was used with the help of Matlab Simulink software. Practical value. Application of the repairment sizes method upon the engine’s cylinder liners has shown improvement of dynamics indicators of car with robotic transmission, which will improve its productivity under excessive engines work conditions.

scholarly journals Comparative Evaluation of Fracture Resistance and Mode of Failure of Zirconia and Titanium Abutments with Different Diameters

2015 ◽  
Vol 16 (8) ◽  
pp. 613-618 ◽  
Author(s):  
Safoura Ghodsi ◽  
Reza Shabanpour ◽  
Niloufar Mousavi ◽  
Marzieh Alikhasi
Keyword(s):  
Fracture Resistance ◽  
Comparative Evaluation ◽  
Failure Modes ◽  
Statistical Significance ◽  
Testing Machine ◽  
Modes Of Failure ◽  
Body Fracture ◽  
Mode Of Failure ◽  
Different Diameters ◽  
Abutment Screw

ABSTRACT Aim The purpose of the current study was to compare the fracture resistance and mode of failure of zirconia and titanium abutments with different diameters. Materials and methods Fourteen groups of abutments including prefabricated zirconia, copy-milled zirconia and titanium abutments of an implant system (XiVE, Dentsply) were prepared in different diameters. An increasing vertical load was applied to each specimen until failure occurred. Fracture resistance was measured in each group using the universal testing machine. Moreover, the failure modes were studied and categorized as abutment screw fracture, connection area fracture, abutment body fracture, abutment body distortion, screw distortion and connection area distortion. Groups were statistically compared using univariate and post-hoc tests. The level of statistical significance was set at 5%. Results Fabrication method (p = 0.03) and diameter (p < 0.001) had significant effect on the fracture resistance of abutments. Fracture resistance of abutments with 5.5 mm diameter was higher than other diameters (p < 0.001). The observed modes of failure were dependent on the abutment material as well. All of the prefabricated titanium abutments fractured within the abutment screw. Abutment screw distortion, connection area fracture, and abutment body fracture were the common failure type in other groups. Conclusion Diameter had a significant effect on fracture resistance of implant abutments, as abutments with greater diameters were more resistant to static loads. Copy-milled abutments showed lower fracture resistance as compared to other experimental groups. Clinical significance Although zirconia abutments have received great popularity among clinicians and even patients selecting them for narrow implants should be with caution. How to cite this article Shabanpour R, Mousavi N, Ghodsi S, Alikhasi M. Comparative Evaluation of Fracture Resistance and Mode of Failure of Zirconia and Titanium Abutments with Different Diameters. J Contemp Dent Pract 2015;16(8):613-618.

Optimisation of Diesel Engine for Hybrid Military Tracked Vehicles using Matlab-Simulink

2017 ◽  
Vol 67 (4) ◽  
pp. 360
Author(s):  
Hari Viswanath ◽  
A. Kumaraswamy ◽  
P. Sivakumar
Keyword(s):  
Diesel Engine ◽  
Dynamic Performance ◽  
Fuel Efficiency ◽  
Negative Power ◽  
Matlab Simulink ◽  
Performance Requirements ◽  
In Series ◽  
And Performance ◽  
High Power Batteries ◽  
Operating Points

<p class="Abstract">The demand in the technology requirements for diesel engines is growing keeping hybrid vehicles in mind. In future the diesel engine no longer drives the wheels directly; as a result the engine can be engaged at a limited number of operating points, thus, offering an opportunity to optimise the fuel efficiency and performance at those operating points. The extent to which this optimisation is possible is limited by practical considerations. Also if the positive and negative power peaks in vehicle during mobility (e.g. acceleration and regenerative braking respectively) can be accommodated by high-power batteries, then the size of the engine can be considerably reduced. The engine’s operating points depend on the power-control strategy. The consequences of modifications to these operating points will have an effect on performance and efficiency. As in series hybrid only a limited number of operating points are involved and dynamic performance requirements are not imposed on the diesel engine, significant improvements can be achieved by the optimisation of the diesel engine at these operating points. The feasibility of optimisation of the engine at these operating points can be done by modification on the injection systems, the valve timings and other such parameters. This kind of approach requires the use of complex and repeated experimental analysis of the engine which is costly, cumbersome and time consuming. An alternative to this kind of experimental approach is to develop a simulation model of the engine with the generator in Matlab- Simulink.</p>

A comparative assessment of cancer-related mortality among workers employed at the various stages of pyrometallurgical production of copper

2019 ◽  
pp. 24-31
Author(s):  
Vadim I. Adrianovskiy ◽  
Georgiy Ya. Lipatov ◽  
Yelena A. Kuz’mina ◽  
Natalya V. Zlygosteva ◽  
Tatyana S. Ustyugova ◽  
...  
Keyword(s):  
Occupational Exposure ◽  
Comparative Evaluation ◽  
Work Conditions ◽  
Comparative Assessment ◽  
Blister Copper ◽  
Copper Recovery ◽  
Furnace Melting ◽  
Study Results ◽  
Related Mortality

The authors present comparative evaluation of influence caused by complex of carcinogenic work conditions of main stages of copper pyrometallic production on cancer-related mortality of the workers. Findings are that raw copper enrichment, blister copper recovery through reverberative furnace melting and f re refining of blister copper are carcinogenic danger for the workers. Malignancies frequency in the workers appeared to directly depend on occupational exposure to arsenic. The results of the workers’ cancer-related mortality correspond to data of carcinogenic risks evaluation at all stages of metallurgic production of copper. Given the study results, reasonable suggestion is to include raw copper enrichment into official list of occupational processes with carcinogenic danger.

Gas Turbine Power Augmentation Technologies: A Systematic Comparative Evaluation Approach

2010 ◽  
Author(s):  
M. Bianchi ◽  
L. Branchini ◽  
A. De Pascale ◽  
F. Melino ◽  
A. Peretto ◽  
...  
Keyword(s):  
Ambient Temperature ◽  
Gas Turbine ◽  
Gas Turbines ◽  
Comparative Evaluation ◽  
Fuel Efficiency ◽  
Heat Rate ◽  
Steam Injection ◽  
Significant Loss ◽  
Evaluation Approach ◽  
Auxiliary Power

Increasing electric rates in peak demand period, especially during summer months, are forcing power producers to look for gas turbine power augmentation technologies (PATs). One of the major undesirable features of all the gas turbines is that their power output and fuel efficiency decreases with increase in the ambient temperature resulting in significant loss in revenues particularly during peak hours. This paper presents a systematic comparative evaluation approach for various gas turbine power augmentation technologies (PATs) available in the market. The application of the discussed approach has been demonstrated by considering two commonly used gas turbine designs, namely, heavy-duty industrial and aeroderivative. The following PATs have been evaluated: inlet evaporative, inlet chilling, high pressure fogging, overspray, humid air injection and steam injection. The main emphasis of this paper is to provide a detailed comparative thermodynamic analysis of the considered PATs including the main variables, such as ambient temperature and relative humidity, which influence their performance in terms of power boost, heat rate reduction and auxiliary power consumption.

scholarly journals Improvement evaluation methodology of vehicle load and energy efficiency

2021 ◽  
pp. 36-44
Author(s):  
Mikhail Podrigalo ◽  
Dmytro Abramov ◽  
Yurii Tarasov ◽  
Mykhailo Kholodov ◽  
Ruslan Kaydalov ◽  
...  
Keyword(s):  
Energy Efficiency ◽  
Power Plants ◽  
Dynamic Properties ◽  
Fuel Efficiency ◽  
Evaluation Methodology ◽  
Design Stage ◽  
Design Production ◽  
Alternative Power ◽  
The Relationship ◽  
Efficiency Indicators

Problem. There was a need to expand the well-known concept of vehicle operational properties – fuel efficiency arose in connection with the advent of new alternative power plants (electric motors, flywheel engines, hybrid power plants, etc.), which requires the inclusion of not only the thermal energy of the fuel, but also other types of energy (electrical and mechanical). In the paper the research of choice and justification of the vehicle energy efficiency indicators by assessing the energy costs of the engine for its movement was made. The analysis of the relationship between energy characteristics of dynamics and vehicle efficiency was made. Goal. The aim of the study is to analyze methods for assessing the vehicle energy efficiency. To achieve this goal, it is necessary to determine indicators that will allow a comparative analysis of energy efficiency indicators of various vehicles. Methodology. The approaches taken in the work to solve this goal are based on substantiating the indicators of the energy efficiency of the car by assessing the energy consumption of the engine for its movement. Results. In our opinion, in projecting and evaluating the dynamic properties of vehicles, it is rational to use the energy indicators of the vehicle, for which it is necessary to develop appropriate assessment criteria. Analysis of the results of indicators calculation and, in table 1, has shown that the indicator in comparison with has less dispersion. Originality. The obtained results of the influence of the parameters of vehicles on the level of their energy load shows that the indicator has less dispersion than. In addition, the value does not correlate with the year of manufacture of the vehicle, which allows the use of this indicator at the design stage of vehicles. It is only necessary to set the rational normative value of this indicator. Practical value. The results obtained can be recommended to specialists for use in the design, production, certification and operation of automotive vehicles, vehicle energy efficiency, combined power plant.

scholarly journals TO THE COMPARATIVE EVALUATION OF FUEL ECONOMY OF THE BTR-70 CAR WITH DIFFERENT TRANSMISSION

2021 ◽  
Vol 1 (50) ◽  
pp. 198-209
Author(s):  
Sakhno V ◽  
◽  
Dykich O ◽  
Keyword(s):  
Fuel Consumption ◽  
Fuel Economy ◽  
Comparative Evaluation ◽  
Gasoline Engine ◽  
Fuel Efficiency ◽  
Steady Motion ◽  
Gear Ratio ◽  
Operating Conditions ◽  
Engine Fuel ◽  
Gasoline Engines

The article considers the issue of choosing a gearbox for the modernization of the BTR-70 by replacing two gasoline engines with two diesels. The object of research is the fuel economy of the BTR-70 car with different gearboxes when replacing two gasoline engines with two diesels. The purpose of the work – to determine the type and gear ratio of the transmission, which provides the best fuel efficiency of the car. Research method - mathematical modeling. When replacing a gasoline engine with a diesel of a different power and a different speed range, it is necessary to determine the gear ratio so as to provide the car with the required level of speed properties in the specified operating conditions with minimal fuel consumption. Due to the fact that the modernization of the BTR-70 involves the replacement of the engine and transmission, the further search for the gearbox was carried out on the basis of analysis of existing structures by the maximum torque of the engine. A five-speed and eight-speed MAZ gearbox and a six-speed Mercedes-Benz G 85-6 / 6.7 gearbox were used for analysis. Taking into account the fact that at a given coefficient of drag  = 0.03 the car can move only in direct gear, then for all gearboxes the fuel characteristics of steady motion will be the same as the control fuel consumption, which was 30 l / 100 km. In terms of fuel consumption during the acceleration of the car and the average kilometer fuel consumption when driving on paved roads, preference should be given to a car with a Mercedes-Benz G 85-6 / 6,7 transmission and only when driving in difficult road conditions, preference should be given to the car with 8-speed MAZ-5335 transmission. KEY WORDS: CAR, ENGINE, FUEL ECONOMY, TRANSMISSION, GEAR RATING, SPEED, COMPARATIVE EVALUATION

scholarly journals Ergonomics & Vibration in Powered Hand Tools Used in Meat Processing

2000 ◽  
Vol 19 (1) ◽  
pp. 1-15 ◽  
Author(s):  
John E. Johnson ◽  
Donald E. Wasserman
Keyword(s):  
Work Conditions ◽  
Time Frame ◽  
Maximum Efficiency ◽  
Meat Processing ◽  
Vibration Acceleration ◽  
Hand Tools ◽  
Vibration Data ◽  
Study Results ◽  
Different Diameters ◽  
Vibration Standards

The purpose of this study was to determine the triaxial acceleration levels of a group of powered circular knives extensively used in the meat processing industry. These tools were tested in real time under actual work conditions while the operators used the tools in 23 different applications. The length of the study was 11 months, encompassing 685 tools, at 13 plant sites using 5 different diameters of circular tools. All vibration tool measurements were recorded from three triaxially mounted individually calibrated, PCB accelerometers. Customized software programs allowed a Gateway 2000 SOLO computer to cycle, collect, and record vibration data for a minimum of a one minute time frame. The study results showed that neither the ANSI S3.34 nor the ACGIH hand-arm vibration standards were exceeded for an 8–hour workday. The median acceleration levels for the five different sized diameter tools did not significantly differ. The operating levels increased only slightly from a new tool that has been determined to be operating at maximum efficiency. Examining the different tool applications, operators, plant locations and tool conditions resulted in concluding that for this type of tool the most important factor contributing to the acceleration intensity levels was tool maintenance and the conditions of its parts. Tools with higher vibration acceleration levels were disassembled and found to have at least one part severely worn or damaged. After the part(s) were replaced, the tool was re-tested under the same work conditions, the vibration acceleration levels on average decreased by 16%. As part of an overall effort, operator exposure to vibration generated by these powered circular knives can be significantly reduced and controlled by proper tool care and maintenance.

Calculating Study of the Diesel Engine Working Process

2020 ◽  
Keyword(s):  
Diesel Engine ◽  
Compression Ratio ◽  
Fuel Injection ◽  
Combustion Engine ◽  
Fuel Efficiency ◽  
Engine Fuel ◽  
Gas Distribution ◽  
Working Process ◽  
Optimal Values ◽  
Efficiency Indicators

A calculating study of the working process of the D-245 diesel engine (4 ChN 11/12,5) produced by the Minsk motor plant is carried out. The influence of compression ratio, fuel injection advance angle and gas distribution phases on the fuel efficiency indicators of the diesel engine under consideration is studied. The optimal values of the diesel engine parameters in various modes of operation are determined. Keywords internal combustion engine, diesel engine, fuel efficiency, compression ratio, fuel injection advance angle, gas distribution phases

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