Analysis of torsional vibration effect on the diesel engine block vibration

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.

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

Design, Application, Performance and Emissions of Modern Internal Combustion Engine Systems and Components ◽

10.1115/ices2003-0578 ◽

2003 ◽

Cited By ~ 2

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.

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Numerical Analysis of Coupled Lateral and Torsional Vibrations of a Vertical Unbalanced Rotor

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.20-23.352 ◽

2010 ◽

Vol 20-23 ◽

pp. 352-357

Author(s):

Xue Li An ◽

Dong Xiang Jiang ◽

Ming Hao Zhao ◽

Chao Liu

Keyword(s):

Torsional Vibration ◽

Coupling Effect ◽

Torsional Vibrations ◽

Lateral Vibration ◽

Transient Vibration ◽

Coupled Vibrations ◽

Lateral Vibrations ◽

Vertical Rotor ◽

Unbalanced Rotor ◽

Mass Eccentricity

A model for the coupled lateral and torsional vibrations of a vertical unbalanced rotor is developed. The equation of motion is obtained using Lagrangian dynamics without considering the external actuating forces and torque. The equation showed coupling and nonlinear interaction between the rotor lateral and torsional vibrations. Most of the earlier work on coupled vibrations has been done for the horizontal rotor model. The coupled vibrations for a vertical rotor have not been reported in the past. An attempt is made to reveal dynamic characteristics of vertical rotor. The results of the simulation showed the coupled between torsional and lateral vibrations is induced by mass eccentricity. Coupled vibrations have appeared in the start period of the vibration. After a transient vibration process, the vibrations are not coupling. The lateral vibration becomes equal amplitude with shafting speed. And the torsional vibration keeps on attenuating until it stops. When the vibration is coupled, the coupling effect on which torsional vibration to lateral vibration is evident. But there’s no coupling effect on the lateral to the torsional. It is also shown that for some operational parameters, the controlling action may excite large lateral vibrations due to coupling with the torsional motion.

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

ASME 2004 Internal Combustion Engine Division Fall Technical Conference ◽

10.1115/icef2004-0808 ◽

2004 ◽

Cited By ~ 1

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.

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Study of Two Stroke Low Speed Diesel Engine Crankshaft Crack Phenomenon by Torsional Vibration Calculation & Measurement

Transactions of the Korean Society for Noise and Vibration Engineering ◽

10.5050/ksnve.2014.24.6.452 ◽

2014 ◽

Vol 24 (6) ◽

pp. 452-461

Author(s):

Joung-Ha Moon ◽

Jeong-Ryul Kim

Keyword(s):

Diesel Engine ◽

Torsional Vibration ◽

Low Speed ◽

Engine Crankshaft

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Low Speed Diesel Engine Block Finite Element Analysis

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.562-564.548 ◽

2012 ◽

Vol 562-564 ◽

pp. 548-551

Author(s):

Zhong Min Liu ◽

Han Yan

Keyword(s):

Diesel Engine ◽

Engine Block ◽

Tetrahedral Mesh ◽

Inertia Force ◽

Main Bearing ◽

Low Speed ◽

Tightening Force ◽

Explosion Pressure ◽

Force Condition ◽

Stress And Deformation

In the analysis of the low speed diesel engine under bolts pre-tightening force, maximum explosion pressure, and piston group of reciprocating inertia force condition, the block main bearing hole values of stress and deformation, for the Mechanical stress analysis of the low speed diesel engine block. First, in the Hypermesh, use the hexahedral mesh near the main bearing hole, use the tetrahedral mesh in other parts. By setting up the grid unit density, control the mesh quality, densify the grid of key parts. And then calculated the stress and deformation of the block by use Abaqus. According the engine performance test data to set the boundary conditions. In the calculation of stress field, analyze the stress distribution and deformation of block under the bolt pre-tightening force, explosion pressure and reciprocating inertia force condition.

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