Online Monitoring ICE Powers Based on the Crankshaft Angular Vibration

2011 ◽  
Vol 48-49 ◽  
pp. 773-778 ◽  
Author(s):  
Chun Rong Hua ◽  
Da Wei Dong ◽  
Bing Yan ◽  
Ming Heng Xu
Keyword(s):  
Reference Point ◽  
Online Monitoring ◽  
Vibration Mode ◽  
Vibration Displacement ◽  
Rotating Speed ◽  
Rigid Body Model ◽  
Angular Vibration ◽  
Cubic Polynomial ◽  
Experimental Researches ◽  
Online Monitor

A new method of online monitoring ICE powers based on the crankshaft angular vibration is proposed. It has deduced that when each cylinder works uniformly at a certain rotating speed, and the vth order angular vibration mode of crankshaft nears plane vibration mode such as “quasi-rigid body model” or “quasi-trapeziform model”, so a cubic polynomial can represent the relationship between the vth order angular vibration displacement amplitude of the crankshaft reference point and the engine powers, thereby the angular vibration of reference point could be used to online monitor engine powers. Through the simulation and experimental researches on a 6240 and a 4100 diesel engine, it shows that the engine powers fitted with the angular vibration displacement amplitudes of reference point are close to the measured or theoretical powers comparatively, and the maximum errors is only 2.95%, which verifies the feasibility and practicability of the method consequently.

Vibration of Lifting Rope when Cage Is Locking

2012 ◽  
Vol 472-475 ◽  
pp. 1559-1562
Author(s):  
Juan Wu
Keyword(s):  
Fundamental Frequency ◽  
Vibration Mode ◽  
Step Function ◽  
Wire Rope ◽  
Vibration Characteristics ◽  
Vibration Displacement ◽  
Mode Function ◽  
Vibration Model

Analysis of vibration characteristics when the cage is locking. Deduce vibration model by elastic lifting rope, interaction of sheave and rope. Based on step function, a wire rope vibration mode function, vibration displacement and tension solution are given. Results show that the cage locking device reduces impact and avoids the slippery rope and the security hidden danger. The vibration model of locking cage process is applied to the cage jammed situation. If the frequency during sudden jam is greater than or equal to the fundamental frequency, hoisting wire rope fracture does not occur.

Design and Research of a New Ultrasonic Atomizing Vibrator

2013 ◽  
Vol 328 ◽  
pp. 468-472
Author(s):  
Hua Li ◽  
Jiang Jiang Zhao ◽  
Zhen Yin ◽  
Kun Ren
Keyword(s):  
Finite Element Analysis ◽  
Steel Sheet ◽  
Vibration Mode ◽  
Simulation Analysis ◽  
Design Method ◽  
Analysis Software ◽  
Element Analysis ◽  
Vibration Displacement ◽  
The Finite Element Analysis ◽  
New Type

Based on the theory of ultrasonic vibration, a new type of ultrasonic atomizing vibrator (UAV) with a vibrating steel sheet was proposed. By using the finite element analysis software to simulation analysis and research for the new type of vibrator, the frequency and vibration mode of atomizing steel sheet was obtained and the prototype of vibrator was fabricated. The impedance and vibration displacement of the vibrator was tested and the experiment of the new type of vibrator was carried out, which verified the feasibility of the new type of vibrator design method.

Controllable Squeeze Film Damper: An Application of Electro-Rheological Fluid

1991 ◽  
Author(s):  
Shin Morishita ◽  
Jun’ichi Mitsui
Keyword(s):  
Apparent Viscosity ◽  
Vibration Mode ◽  
Squeeze Film ◽  
Damping Capacity ◽  
Flexible Rotor ◽  
Rotor Vibration ◽  
Squeeze Film Damper ◽  
Rotating Speed ◽  
Wide Range ◽  
Er Fluid

Abstract A notable characteristic of Electro-Rheological (ER) fluid is the variation of its apparent viscosity with the application of an electric field. The application of this characteristic to the performance of squeeze film damper of a flexible rotor is investigated in this paper. It is shown experimentally that by controlling the supporting damping capacity continuously, rotor vibration can be reduced remarkably in a wide range of rotating speed. Moreover, the study indicates experimentally that there exists an optimum supporting damping for every vibration mode.

scholarly journals Study on the Nonlinear Characteristics of a Rotating Flexible Blade with Dovetail Interface Feature

2018 ◽  
Vol 2018 ◽  
pp. 1-13 ◽  
Author(s):  
Chaofeng Li ◽  
Zengchuang Shen ◽  
Bingfu Zhong ◽  
Bangchun Wen
Keyword(s):  
Dry Friction ◽  
Piecewise Linear ◽  
Vibration Reduction ◽  
External Excitation ◽  
Stick Slip ◽  
Nonlinear Characteristics ◽  
Rotating Speed ◽  
Rotating Blade ◽  
Reduction Characteristics ◽  
Experimental Researches

A dynamic model is proposed in this paper for analyzing the nonlinear characteristics of a flexible blade. The dynamical equation of motion for a rotational flexible blade in a centrifugal force field is established based on the finite element method. A macro-stick-slip mechanical model of dry friction is established to simulate the constraint condition of the flexible blade. The combined motion of the external excitation and friction produces a piecewise linear vibration which is actually nonlinear. The numerical integration method is employed to calculate the vibration reduction characteristics of the nonlinear constrained rotating blade. The results show that the nonlinear dry friction force produced by the dovetail interface plays an important role in vibration reduction. And the effect of dry friction vibration reduction is significant when the rotating speed is slow or the friction coefficient is small. Besides, the magnitude of external excitation also has a great impact on the state of the friction. Therefore, some relevant experimental researches should be done in the future.

Dynamics Study and Damping Optimization of Circular Saw Based on Numerical Simulation and Experimental Analysis

2012 ◽  
Vol 201-202 ◽  
pp. 364-369 ◽  
Author(s):  
Ming Hong Yuan ◽  
Shui Guang Tong ◽  
Qin Cai ◽  
Ning Tang
Keyword(s):  
Numerical Simulation ◽  
Finite Element ◽  
Numerical Calculation ◽  
Experimental Analysis ◽  
Vibration Mode ◽  
Damping Ratio ◽  
Modal Testing ◽  
Vibration Displacement ◽  
Circular Saw ◽  
Cutting Vibration

Serious vibration and noise exists in the circular saw cutting process. In order to reduce the cutting vibration and noise, this paper uses the finite element numerical calculation and modal testing analysis to study the dynamic characteristics of the circular saw blades, obtain the circular saw’s kinetic parameters, such as each order natural frequency, the main vibration mode and damping ratio, evaluate the circular saw system’s dynamic response. Through the optimization of slotted design and experimental analysis, a circular saw with reasonable structure reduces the maximum vibration displacement of 11.1% which increases the circular saw blades cutting quality, prolongs the service life and reduces the cutting noise.

Online monitoring experiments of turbo-shaft engine based on electrostatic sensor

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Jiachen Guo ◽  
Heng Jiang ◽  
Zhirong Zhong ◽  
Hongfu Zuo ◽  
Huan Zhang
Keyword(s):  
Online Monitoring ◽  
Health Management ◽  
Charged Particles ◽  
Content Type ◽  
Rotating Speed ◽  
Short Timescale ◽  
Frequency Domain Methods ◽  
Aero Engine ◽  
Component Faults ◽  
Practical Implications

Purpose Electrostatic monitoring technology is a useful tool for monitoring and detecting component faults and degradation, which is necessary for engine health management. This paper aims to carry out online monitoring experiments of turbo-shaft engine to contribute to the practical application of electrostatic sensor in aero-engine. Design/methodology/approach Combined with the time and frequency domain methods of signal processing, the authors analyze the electrostatic signal from the short timescale and the long timescale. Findings The short timescale analysis verifies that electrostatic sensor is sensitive to the additional increased charged particles caused by abnormal conditions, which makes this technology to monitor typical failures in aero-engine gas path. The long scale analysis verifies the electrostatic sensor has the ability to monitor the degradation of the engine gas path performance, and water washing has a great impact on the electrostatic signal. The spectrum of the electrostatic signal contains not only the motion information of the charged particles but also the rotating speed information of the free turbine. Practical implications The findings in this article prove the effectiveness of electrostatic monitoring and contribute to the application of this technology to aero-engine. Originality/value The research in this paper would be the foundation to achieve the application of the technology in aero-engine.

Study on Weld Shaping and Mechanical Properties for Three Movement Types of Arc Welding Robot Torch

2011 ◽  
Vol 127 ◽  
pp. 187-191 ◽  
Author(s):  
Jian Ping Jia ◽  
Jian Ping Chen ◽  
Yun Long Liu ◽  
Ya Qin Zhang
Keyword(s):  
Mechanical Properties ◽  
Arc Welding ◽  
High Speed ◽  
Weld Seam ◽  
Welding Robot ◽  
Fillet Weld ◽  
Rotating Speed ◽  
Arc Sensor ◽  
Experimental Researches ◽  
Better Than

Compared with the existing arc sensors, high speed rotating scanning arc sensor has up to 50 HZ rotating speed, and it can be much more compact, cheaper and more sensitive. The arc welding robot can weld for three movement types using the high speed rotating scanning arc sensor. Weld shaping and mechanical properties for three movement styles of arc welding robot torch are studied. The macrostructure appearance characteristics of mild steel bead-on-plate weld seam section and fillet weld seam section are analyzed. Experimental researches are undertaken in tension and bending test.The results show that the weld shaping of rotating arc weld for bead-on-plate weld and fillet weld is better than that of linear motion arc welding and oscillating arc welding. This investigation will provide the theoretical basis for the advantage and choice of three arc movement styles in the practical production.

Machining force observer considering angular vibration mode for multi-axis machine tool

2018 ◽  
Vol 2018 (0) ◽  
pp. S1350103
Author(s):  
Hayato YOSHIOKA ◽  
Sou FUKASAWA ◽  
Norikazu SUZUKI ◽  
Yasuhiro KAKINUMA
Keyword(s):  
Machine Tool ◽  
Vibration Mode ◽  
Machining Force ◽  
Angular Vibration

Study on Optimization Design of VSR Parameter for Large Welded Components

2015 ◽  
Vol 1120-1121 ◽  
pp. 1281-1286
Author(s):  
Xi Zhang ◽  
Xue Wu Dong ◽  
Dai Ren ◽  
Yan Ting Wang ◽  
Jian Hui Han ◽  
...  
Keyword(s):  
Residual Stress ◽  
Stress Distribution ◽  
Optimization Design ◽  
Vibration Mode ◽  
Excitation Frequency ◽  
Vibration Displacement ◽  
Technical Parameters ◽  
Natural Modes ◽  
Key Factor ◽  
Excitation Force

This article studies optimization design of Vibratory stress relief (VSR) technology parameter for large welded components. The test is carried through a large welded truss. It first analysis key factor of the influence on VSR technology effect. And then by modal analysis, we’ve got the natural frequency and natural modes of the specimen , The optimization design is based on residual stress distribution and natural modes of component for VSR process parameters. Test pieces are treated by vibration. before and after vibration, residual stress of the specimens is measured by the method of blind hole.The results showed that vibration mode is a key factor in determining the effect of VSR. Stress distribution is more complex for large welded components.As accordance by selecting a few of vibration modes, for VSR main technical parameters design, it can get enough vibration displacement in the areas and directions of component with residual stress. Thus we can have a good effects to relief welding residual stress.Three major parameters (Excitation frequency, excitation point, support points) are related with vibration mode. They are decided by selecting vibration mode. Excitation force is decided based excitation frequency as well as the size of the exciter eccentric , to get the right excitation force by adjusting the size of the exciter eccentric under the condition of the selected excitation frequency.

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