A NOTE ON THE EXPERIMENTALLY DETERMINED ELASTODYNAMIC RESPONSE OF A SLIDER–CRANK MECHANISM FEATURING A MACROSCOPICALLY SMART CONNECTING ROD WITH CERAMIC PIEZOELECTRIC ACTUATORS AND STRAIN GAUGE SENSORS

1995 ◽  
Vol 187 (4) ◽  
pp. 718-723 ◽  
Author(s):  
B.S. Thompson ◽  
X. Tao
Keyword(s):  
Strain Gauge ◽  
Piezoelectric Actuators ◽  
Connecting Rod ◽  
Elastodynamic Response ◽  
Crank Mechanism

A Note on the Experimentally-Determined Elastodynamic Response of a Slider-Crank Mechanism Featuring a Macroscopically-Smart Connecting-Rod With Ceramic Piezoelectric Actuators and Strain Gage Sensors

1994 ◽  
Author(s):  
B. S. Thompson ◽  
X. Tao
Keyword(s):  
Strain Gage ◽  
Smart Materials ◽  
Piezoelectric Plate ◽  
Preliminary Investigation ◽  
Theoretical Studies ◽  
Connecting Rod ◽  
Flexural Response ◽  
Elastodynamic Response ◽  
New Generation ◽  
Crank Mechanism

Abstract An experimental investigation is presented into the elastodynamic flexural response of a smart flexible connecting-rod of a planar slider-crank mechanism which features both macroscopic actuators and sensors. This connecting-rod was synthesized with two thin PZT ceramic piezoelectric plate actuators bonded to the flanks of the beam-like member at the mid-span of the link, which were employed to reduce the magnitude of the flexural response when they were activated by amplified signals emulating from two strain gage sensors bonded to the surfaces of the piezoceramic actuators. The authors believe that this is the first paper to present experimental results for a linkage featuring this class of smart materials, and these results will hopefully motivate more theoretical studies on mechanism systems fabricated from this class of biomimetic materials. The results from this preliminary investigation add credibility to the proposition that this new generation of macroscopically smart materials will have a significant role to play in the design of the next generation of machines and mechanisms.

Vibration Analysis of the Flexible Connecting Rod With the Breathing Crack in a Slider-Crank Mechanism

2013 ◽  
Vol 135 (6) ◽  
Author(s):  
Yan-Shin Shih ◽  
Chen-Yuan Chung
Keyword(s):  
Governing Equation ◽  
Moving Boundary ◽  
Beam Theory ◽  
Crack Model ◽  
Breathing Crack ◽  
Connecting Rod ◽  
Bernoulli Beam ◽  
The Galerkin Method ◽  
Euler Bernoulli Beam ◽  
Crank Mechanism

This paper investigates the dynamic response of the cracked and flexible connecting rod in a slider-crank mechanism. Using Euler–Bernoulli beam theory to model the connecting rod without a crack, the governing equation and boundary conditions of the rod's transverse vibration are derived through Hamilton's principle. The moving boundary constraint of the joint between the connecting rod and the slider is considered. After transforming variables and applying the Galerkin method, the governing equation without a crack is reduced to a time-dependent differential equation. After this, the stiffness without a crack is replaced by the stiffness with a crack in the equation. Then, the Runge–Kutta numerical method is applied to solve the transient amplitude of the cracked connecting rod. In addition, the breathing crack model is applied to discuss the behavior of vibration. The influence of cracks with different crack depths on natural frequencies and amplitudes is also discussed. The results of the proposed method agree with the experimental and numerical results available in the literature.

scholarly journals Design of a prototype of an engine mechanism with rotating cylinders

2020 ◽  
Vol 318 ◽  
pp. 01004
Author(s):  
Miroslav Blatnický ◽  
Ján Dižo
Keyword(s):  
High Speed ◽  
Cooling System ◽  
Ambient Air ◽  
Combustion Engines ◽  
Connecting Rod ◽  
Rotating Cylinders ◽  
Liquid Cooling ◽  
Working Cycle ◽  
Liquid Cooling System ◽  
Crank Mechanism

In this article, authors focus on the design and construction of a real prototype of an engine mechanism with rotating cylinders and its using mainly in piston combustion engines. It is assumed, that the normal force of a piston will be completely eliminated, because the swing angle of a connecting rod will equal to zero during the whole working cycle, since the connecting arm of the piston moves just the cylinder axis. It will by allowed by the conceptual design of the mechanism presented in this article. As rotating blocks of cylinders concurrently act as a flywheel, it is proposed, that in this way there is possible to save the mass of additional flywheels. Moreover, liquid cooling system is not necessary, because the rotating cylinders sufficiently transfer heat to ambient air. In addition, the output of torque will be reached without necessity of gear transmission, which results to decreasing of needs of mechanism lubrication. Other advance of the designed mechanism are two outputs. The first output is low-speed and it goes out from rotating cylinders, i. e. from the slider-crank mechanism with revolutions n1. The other output is high-speed, from the crankshaft with revolutions n2. Because of more favourable properties of the mechanism, authors have decided to create a real device to confirm all mentioned advantages of the mechanism by the suitable way.

Vibrations of Elastic Connecting Rod of a High-Speed Slider-Crank Mechanism

1971 ◽  
Vol 93 (2) ◽  
pp. 636-644 ◽  
Author(s):  
Peter W. Jasinski ◽  
Ho Chong Lee ◽  
George N. Sandor
Keyword(s):  
Small Parameter ◽  
High Speed ◽  
Elastic Stability ◽  
Method Of Averaging ◽  
Connecting Rod ◽  
Transverse Vibrations ◽  
Elastic Bar ◽  
The Moment ◽  
Steady State Solutions ◽  
Crank Mechanism

The research involved in this paper falls into the area of analytical vibrations applied to planar mechanical linkages. Specifically, a study of the vibrations, associated with an elastic connecting-bar for a high-speed slider-crank mechanism, is made. To simplify the mathematical analysis, the vibrations of an externally viscously damped uniform elastic connecting bar is taken to be hinged at each end (i.e., the moment and displacement are assumed to vanish at each end). The equations governing the vibrations of the elastic bar are derived, a small parameter is found, and the solution is developed as an asymptotic expansion in terms of this small parameter with the aid of the Krylov-Bogoliubov method of averaging. The elastic stability is studied and the steady-state solutions for both the longitudinal and transverse vibrations are found.

Balancing the Moments of a VR5 Engine Taking into Account a Desaxial Crank Mechanism and Cylinder Camber Angle

2020 ◽  
pp. 41-49
Author(s):  
N.D. Chainov ◽  
P.R. Vallejo Maldonado
Keyword(s):  
Relative Displacement ◽  
Working Fluid ◽  
Inertial Forces ◽  
Structural Elements ◽  
Connecting Rod ◽  
Cylinder Axis ◽  
Acoustic Characteristics ◽  
Camber Angle ◽  
Inertia Forces ◽  
Crank Mechanism

Automobile piston engines with a desaxial crank mechanism are characterized by increased vibration activity associated with a cyclic change in the pressure of the working fluid in the cylinders and inertial forces associated with the reciprocating and rotational movement of the crank mechanism moving masses. Properties reflecting the consumer properties of the engine, including acoustic characteristics, are largely determined by the level of vibration of the structural elements of the desaxial crank mechanism and, first of all, by the balance of inertial forces during operation. The article discusses balancing of five-cylinder four-stroke VR type engines with a desaxial crank mechanism and uniform flash alternation. The authors introduce formulas that can be used to determine and analyze moments of the inertia forces of the reciprocating and rotating masses arising in VR5 engines at the set values of the cylinder camber angle, the ratio of the crank radius to the connecting rod length and the relative displacement of the cylinder axis. A method of balancing the moments of inertia forces of the reciprocating and rotating masses is proposed.

Member Initial Curvature Effects on the Elastic Slider-Crank Mechanism Response

1982 ◽  
Vol 104 (1) ◽  
pp. 159-167 ◽  
Author(s):  
M. Badlani ◽  
A. Midha
Keyword(s):  
Steady State ◽  
Natural Frequency ◽  
Equations Of Motion ◽  
Excitation Frequency ◽  
Beam Theory ◽  
Connecting Rod ◽  
Initial Curvature ◽  
Curvature Effects ◽  
Transient Solutions ◽  
Crank Mechanism

Parametric vibration of initially curved columns loaded by axial-periodic loads has received considerable attention, concluding that regions of instability exist and that excitation frequencies less than the natural frequency of the principal resonance may occur. Recent publications have cautioned against the use of curved members in machines designed for precise operation, suggesting a detrimental coupling of the longitudinal and transverse deformations. In this work, the dynamic behavior of a slider-crank mechanism with an initially curved connecting rod is investigated. Governing equations of motion are developed using the Euler-Bernoulli beam theory. Both steady-state and transient solutions are determined, and compared with those obtained for the mechanism possessing a geometrically perfect (straight) connecting rod. A very small initial curvature is shown to cause a significantly greater steady-state response. The magnification in its transient response is shown to be even greater than that due to a straight connecting rod. Additionally, an excitation frequency less than the natural frequency is also shown to occur.

scholarly journals Large bore engine connecting rod fretting analysis

2017 ◽  
Vol 50 (3) ◽  
pp. 239-243 ◽  
Author(s):  
Antti Mäntylä ◽  
Jussi Göös ◽  
Anton Leppänen ◽  
Tero Frondelius
Keyword(s):  
Friction Coefficient ◽  
Strain Gauge ◽  
Contact Analysis ◽  
Connecting Rod ◽  
Coefficient Distribution ◽  
Strain Gauge Measurements

A detailed contact analysis of a large connecting rod was performed to evaluatethe fretting risk in the big end. Simulation was carried out in Abaqus considering all relevantboundary conditions, such as assembly loads, housing machining and dynamics from a exiblemultibody simulation with elastohydrodynamic bearings. Being one of the most importantvariables, the local coeffcient of friction (COF) and its evolution is calculated during the solutionby using a subroutine in Abaqus. The model is validated by strain gauge measurements in arunning engine. The resulted friction coefficient distribution matches well with the ndings froma laboratory engine. The described methodology increases the accuracy of the fretting damageprediction by using a more realistic friction coefficient denition.

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