Analysis for Strain on Torsional Damper Rubber and Torsional Vibration on Crankshaft for a Diesel Engine

2004 ◽  
Author(s):  
Jouji Kimura ◽  
Katsukimi Takayama
Keyword(s):  
Diesel Engine ◽  
Torsional Vibration ◽  
Engine Speed ◽  
Significant Degree ◽  
Torsional Vibrations ◽  
Torsional Strain ◽  
The Relationship

A torsional damper is attached to a crankshaft pulley to control torsional vibration. Torsional strain is produced on the rubber when it is placed between the damper plate and the damper ring. The authors know from our experience that, in some engines, especially in turbo-charged engines, such a significant degree of strain is produced on the damper rubber at a resonant engine speed that the rubber is torn off in two pieces. This paper presents a method of estimating strain caused by torsional vibrations and discusses the relationship between the crankshaft torsional vibration and the strain.

Crankshaft Torsional Vibration Characteristics in a Vee-Type Six-Cylinder Diesel Engine

2002 ◽  
Author(s):  
Jouji Kimura ◽  
Shinichirou Kobayashi ◽  
Kazuhiro Shiono
Keyword(s):  
Diesel Engine ◽  
Torsional Vibration ◽  
Engine Speed ◽  
Significant Degree ◽  
Vibration Characteristics ◽  
Resonant Vibration ◽  
Harmonic Order ◽  
Engine Speed Range ◽  
Speed Range

Engines have been designed to avoid low-harmonic-order resonant torsional vibration in a commonly-used engine speed range, but the authors have found that, in some engines, especially turbo-charged engines, a significant degree of a low-harmonic-order exciting torque acts on the crankshaft. In these engines, the amplitude of non-resonant low-harmonic-order torsional vibration is almost as large as that of the resonant one and the amplitude of non-resonant vibration can not be controlled by a damper. Accordingly, to investigate the characteristics of non-resonant low-harmonic-order torsional vibration is important. This paper describes the characteristics of non-resonant and resonant torsional vibration for a vee-type six-cylinder diesel engine.

Transient and Unstable Torsional Vibrations on a 4-Stroke Marine Diesel Engine

2003 ◽  
Author(s):  
D. C. Lee ◽  
J. D. Yu
Keyword(s):  
Diesel Engine ◽  
Torsional Vibration ◽  
Marine Diesel Engine ◽  
Torsional Vibrations ◽  
Steady State Condition ◽  
Marine Propulsion ◽  
Friction Clutch ◽  
Marine Diesel ◽  
Noise Measurements ◽  
Unstable Vibration

Under steady state condition, unstable torsional vibration normally does not occur in shafting systems using 4stroke diesel engine due to hysteresis damping of shafting system and relative damping of standard fitted damper. However, the unstable torsional vibration occurs on marine propulsion shafting systems due to slippage of a multi-friction clutch installed between increasing gear box and shaft generator. To identify this unstable vibration and make proper counter measure, the simulation for transient torsional vibration using the Newmark method is introduced in this paper. The mechanism of this unstable vibration is verified by vibration and noise measurements of the shafting system.

Research on the Method of Circumferential Spring Dual Mass Flywheel Damper Matching with Diesel Engine

2009 ◽  
Vol 419-420 ◽  
pp. 65-68
Author(s):  
Zheng Feng Jiang ◽  
Lei Chen
Keyword(s):  
Diesel Engine ◽  
Torsional Vibration ◽  
Torsional Stiffness ◽  
Vibration Damper ◽  
Passenger Car ◽  
Inertia Coefficient ◽  
New Type ◽  
Working Principle ◽  
Relationship Of ◽  
The Relationship

As a new type of torsional vibration damper, a Dual Mass Flywheel (DMF) has different configuration and working principle from the traditional clutch. Focusing on the problem of matching DMF with a diesel engine, the relationship of circumferential spring dual mass flywheel (CS-DMF) and gearbox is analyzed based on a multi-freedom model, and then the methods of gearbox selection, rotary inertia coefficient ascertain and optimization of torsional stiffness are proposed in this paper. The methods have been applied to a CS-DMF matching with a passenger car with diesel engine. Modal simulation and torque fluctuating experiment show the CS-DMF has excellent damping performance.

scholarly journals Analysis of torsional vibration effect on the diesel engine block vibration

2020 ◽  
Vol 21 (5) ◽  
pp. 522
Author(s):  
Shiwei Ni ◽  
Yibin Guo ◽  
Binglin Lv ◽  
Donghua Wang ◽  
Wanyou Li ◽  
...  
Keyword(s):  
Finite Element Method ◽  
Diesel Engine ◽  
Torsional Vibration ◽  
Coupling Effect ◽  
Fem Simulation ◽  
Vibration Response ◽  
Engine Block ◽  
Torsional Vibrations ◽  
Low Speed ◽  
Vibration Effect

In this paper, the coupling effect between the crankshaft torsional vibration and the low speed diesel engine block vibration is investigated. Using finite element method (FEM), a model of low speed diesel engine is established to study the vibration response. The mode results of FEM agree very well with the test. The additional torques acting on the low-speed diesel engine caused by torsional vibration are discussed in detail. The vibration response of the low-speed diesel engine considering the effect of torsional vibration is studied using FEM simulation. By analyzing the effect of torsional vibration, the results demonstrate that the crankshaft torsional vibrations have important effects on the engine block vibration. The results from this study can provide useful theoretical guidance to predict vibration of low-speed diesel engine.

scholarly journals Computer Modelling For 4-Stroke Direct Injection Diesel Engine

2008 ◽  
Vol 33-37 ◽  
pp. 801-806
Author(s):  
Abdul Rahim Ismail ◽  
Rosli Abu Bakar ◽  
Semin Ali ◽  
Ismail Ali
Keyword(s):  
Diesel Engine ◽  
Simulation Study ◽  
Engine Speed ◽  
Computer Modelling ◽  
Direct Injection ◽  
One Dimension ◽  
Effective Pressure ◽  
Operational Parameters ◽  
Direct Injection Diesel Engine ◽  
Theoretical Results

Study on computational modeling of 4-stroke single cylinder direct injection diesel engine is presented. The engine with known specification is being modeled using one dimension CFD GT-Power software. The operational parameters of the engine such as power, torque, specific fuel consumption and mean effective pressure which are dependent to engine speed are being discussed. The results from the simulation study are compared with the theoretical results to get the true trend of the results.

Study on Electro-Pneumatic Clutch for Automatic Mechanical Transmission

2011 ◽  
Vol 148-149 ◽  
pp. 1149-1153
Author(s):  
Wu Chao Zhang ◽  
Yong Zhai
Keyword(s):  
Diesel Engine ◽  
Field Experiment ◽  
Control Strategy ◽  
Engine Speed ◽  
Mechanical Transmission ◽  
Control Law ◽  
Clutch Engagement ◽  
Automotive Powertrain ◽  
System Requirements ◽  
Clutch Control

The clutch control is one of the cores and most difficult issues in the development of an AMT system. In this paper the pneumatic clutch engagement characteristic is analyzed. Thereto, a simulation model of an automotive powertrain comprises a diesel engine, drivetrain and wheels driving a vehicle through tire-road adhesion are built using Matlab/Simulink. In the simulation, a refined control law of constant engine speed in part process is proposed and tested. The engaging speed and displacement of the clutch vary with the accelerate paddle opening, engine speed, clutch driven plate speed and gears according the control law. Field experiment results show that the control strategy fulfills the system requirements.

A Spray-Droplet Model for Diesel Combustion

1969 ◽  
Vol 184 (10) ◽  
pp. 28-35 ◽  
Author(s):  
J. Shipinski ◽  
P. S. Myers ◽  
O. A. Uyehara
Keyword(s):  
Experimental Data ◽  
Diesel Engine ◽  
Heat Release ◽  
Engine Speed ◽  
Chamber Pressure ◽  
Gas Temperature ◽  
Single Droplet ◽  
Burning Rates ◽  
Burning Model ◽  
The One

A spray-burning model (based on single-droplet theory) for heat release in a diesel engine is presented. Comparison of computations using this model and experimental data from an operating diesel engine indicate that heat release rates are not adequately represented by single-droplet burning rates. A new concept is proposed, i.e. a burning coefficient for a fuel spray. Comparisons between computations and experimental data indicate that the numerical value of this coefficient is nearly independent of engine speed and combustion-chamber pressure. However, the instantaneous value of the spray burning coefficient is approximately proportional to the instantaneous mass-averaged cylinder gas temperature to the one-third power.

Effect of Vibration on Rapeseed Header Loss and Optimization of Header Frame

2021 ◽  
Vol 64 (4) ◽  
pp. 1247-1258
Author(s):  
Yang Li ◽  
Lizhang Xu ◽  
Zhipeng Gao ◽  
En Lu ◽  
Yaoming Li
Keyword(s):  
Modal Analysis ◽  
Engine Speed ◽  
Vibration Measurement ◽  
List Type ◽  
Positive Correlation ◽  
Combine Harvester ◽  
Analysis System ◽  
Combine Harvesters ◽  
Relationship Of ◽  
The Relationship

HighlightsThe relationship of vibration and header loss was studied by multi-point vibration measurement and loss collection test.There was an approximately linear positive correlation between total header vibration and total rapeseed header loss.The header frame was analyzed and optimized through modal simulation and testing.The total rapeseed header loss of the improved header was reduced by 33.2% to 46.9%.Abstract. In view of the current large rapeseed header losses of rape combine harvesters, the effects of the header on rapeseed header loss were studied from the perspective of vibration. First, the vibrations at various measuring points on the header during rape harvest were studied using a data acquisition and analysis system while performing collection tests of rapeseed header loss with the sample slot method. The relationships between total header vibration and total rapeseed header loss and between vertical cutter vibration and rapeseed vertical cutter loss were shown to have a positive correlation, and they all increased with the increase in engine speed. Vertical cutter loss accounted for 31.2% to 42.4% of the total rapeseed header loss. Modal analysis and optimization of the header frame were then performed by simulation and test. The natural frequencies of the first-order and second-order modes of the optimized header were increased, and the possibility of resonance with other working parts was eliminated. Finally, the improved header was tested during rape harvest. The results showed that the total vibration of the improved header was reduced by 19.9% to 43.9%, and the total rapeseed header loss was reduced by 33.2% to 46.9%. The vertical cutter vibration was reduced by 30.5% to 49.8%, and the rapeseed vertical cutter loss was reduced by 20.8% to 34.7%. In addition, the vibration and rapeseed loss of the improved header had relatively slow rates of increase with the increase in engine speed. The method of reducing rapeseed loss by reducing the header vibration achieved an obvious and positive effect. Keywords: Frame optimization, Modal analysis, Rape combine harvester, Rapeseed header loss, Vibration.

Mathematics Grade as Correlate to Performance in the National Achievement Test

2020 ◽  
Vol 8 (1) ◽  
pp. 31-41
Author(s):  
Daryl T. Paredes ◽  
Ronalyn G. Albopera ◽  
Gladys T. Balog ◽  
Vincent A. Buladas ◽  
Mary Grace D. Hoyle ◽  
...  
Keyword(s):  
Academic Performance ◽  
Significant Degree ◽  
Achievement Test ◽  
Department Of Education ◽  
Test Results ◽  
Achievement Level ◽  
School Year ◽  
Documentary Analysis ◽  
Student’S Performance ◽  
The Relationship

Tests in schools can be informative. However, the Department of Education administered a set of examinations like the National Achievement Test which is designed to determine the learner's achievement level, strengths, and weaknesses in five curricular subject areas at the end of the school year. The study intended to look into the relationship between academic performance in Mathematics and NAT results. There has been a purposive universal sampling design. It is purposive because the research is only studying the academic performance in Mathematics, and universal because the subjects of the study are all the grade six pupils of Victoriano D. Tirol Advanced Learning Center for four consecutive school years. Documentary analysis was used as to the data of existing records on the academic performance and National Achievement Test results in Mathematics. The association between academic achievement and NAT outcomes in Mathematics was investigated using correlation analysis and one-way analysis of variance (ANOVA). The analyses revealed that there is a significant correlation between the pupil's academic performance and NAT results. Also, there is a significant degree of variance in the student's performance as to National Achievement Test Results in four consecutive school years.

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