Dynamic Synthesis of Cams Using Finite Trigonometric Series

1975 ◽  
Vol 97 (1) ◽  
pp. 287-293 ◽  
Author(s):  
J. L. Wiederrich ◽  
B. Roth
Keyword(s):  
Mathematical Model ◽  
Trigonometric Series ◽  
High Speed ◽  
Dynamic Performance ◽  
Design Rules ◽  
New Methods ◽  
Dynamic Synthesis ◽  
High Speeds ◽  
Rules Of Thumb ◽  
Empirical Design

New methods are presented for the design of high-speed cam profiles. These methods have the advantage of assuring the accuracy of the assumed mathematical model while at the same time providing for good dynamic performance. These methods do not rely on rules of thumb. In fact, it is shown that at high speeds low vibration motions exist which violate heretofore commonly accepted empirical design rules.

scholarly journals Suspending force modeling based on nonlinear acoustics and high-speed running experiments for an ultrasonic journal bearing

2020 ◽  
Vol 12 (7) ◽  
pp. 168781402094047
Author(s):  
He Li ◽  
Yu Wang ◽  
Deen Bai ◽  
Fuyan Lyu ◽  
Kuidong Gao ◽  
...  
Keyword(s):  
Lead Zirconate Titanate ◽  
Smart Materials ◽  
High Speed ◽  
Acoustic Radiation ◽  
Dynamic Performance ◽  
Force Model ◽  
Trajectory Data ◽  
Running Performance ◽  
High Speeds ◽  
Radiation Theory

As a kind of promising noncontact bearings, ultrasonic bearings actuated by smart materials such as lead zirconate titanate ceramics show a good application prospect in high-speed machines and precision-measuring devices. The suspending force is one of the most important parameters that play a dominated role on the bearing’s static and dynamic performance. A suspending force model based on acoustic radiation theory for cylindrical object near sound source is built to predict the radial carrying capacity of an ultrasonic bearing actuated by three piezoelectric transducers. To validate the model, an ultrasonic bearing prototype is developed and a testing system is established. For observing the bearing’s dynamic running performance at high speeds, the bearing’s running experiment is carried out and the rotor center’s trajectory data and frequency spectrum are acquired to analyze the bearing’s dynamic characteristics at high speeds. The suspending force model and running performance experiments will contribute to the design, detection, and test of this type of bearings.

An Integrated Approach to the Design and Analysis of an Ultra-High Speed Air-Bearing Spindle

2012 ◽  
Vol 723 ◽  
pp. 227-232 ◽  
Author(s):  
Si Yu Gao ◽  
Hui Ding ◽  
Kai Cheng
Keyword(s):  
High Speed ◽  
Dynamic Performance ◽  
Integrated Approach ◽  
System Optimization ◽  
Air Bearing ◽  
Design Environment ◽  
Virtual Design ◽  
High Speeds ◽  
Ultra High Speed ◽  
Structural Behaviors

This paper presents an integrated approach to the design and analysis of an ultra-high speed air bearing spindle, by integrating the structural design, performance analysis and system optimization in a virtual design environment. Firstly, the ultra-high speed air bearing spindle is designed, including grooved hybrid air bearing, helical water cooling channel and built-in motor, etc; Subsequently, pneumatic hammer instability and whirl instability of air bearing are studied; The thermal-structural behaviors of the spindle system at ultra-high speeds are investigated by using structural FEA coupled CFD; Static and dynamic performance of spindle is studied to predict the stiffness, modes and natural frequencies of the spindle; Lastly, system optimizations are conducted to obtain optimal performance and dynamic behaviors of the spindle. The proposed integrated approach can be used to design an optimal ultra-high speed air bearing spindle.

An Efficient Finite Element Procedure for Analysis of High-Speed Spiral Groove Gas Face Seals

2000 ◽  
Vol 123 (1) ◽  
pp. 205-210 ◽  
Author(s):  
Marco Tulio C. Faria
Keyword(s):  
Finite Element ◽  
High Speed ◽  
Dynamic Performance ◽  
Dynamic Force ◽  
Spiral Groove ◽  
Weighted Residual Method ◽  
New Class ◽  
High Speeds ◽  
Face Seals ◽  
Finite Element Procedure

An efficient and accurate finite element procedure is specially devised to analyze the performance of gas-lubricated spiral groove face seals operating at high speeds. The procedure is based on the Galerkin weighted residual method with a new class of high-order shape functions, which are derived from an approximate solution to the nonlinear Reynolds equation within an element. Static and dynamic performance characteristics, such as seal opening force, flow leakage and frequency-dependent dynamic force coefficients, are determined to study the effects of high speeds on the behavior of spiral groove gas face seals.

Simulation and Experimental Investigations of a Digital High Speed Close Loop Proportional Directional Valve Using a Solenoid Technology

2016 ◽  
Author(s):  
Dario Buono ◽  
Adolfo Senatore ◽  
Emma Frosina ◽  
Wade Gehlhoff ◽  
Ina I. Costin
Keyword(s):  
Mathematical Model ◽  
Systems Engineering ◽  
Digital Control ◽  
High Speed ◽  
Dynamic Performance ◽  
Simulation Models ◽  
Experimental Tests ◽  
Experimental Investigations ◽  
Proportional Valve ◽  
Modeling Technology

This paper describes the design, simulation and testing of a high response servo-proportional valve. The purpose of this work is to study the possibilities, using a modeling technology, to increase the dynamic performance of a servo-proportional directional developing new algorithms for the digital control system. The development of digital technology, introduced also in the control of proportional valves, have led to the reduction of the differences between the overall characteristics of proportional and servo valves so that the proportional ones can be a suitable solution in many applications, where servo-valves are traditionally used. The mathematical model of the servo-proportional valve has been developed by using the commercial software AMESim® (Advanced Modeling and Simulation Environment for Systems Engineering). The model includes the proportional solenoid and the linear transducer. Digital control of the proportional valve proposed in this paper, is a key part of this research. Its mathematical model and the control algorithm have been built using Matlab®. Both models have been run in co-simulation to improve the overall valve performance. The experimental tests have been performed in the labs of Duplomatic Oleodinamica SpA and Continental Hydraulic Inc. The data have been used to validate the simulation models.

A COMPARATIVE STUDY OF CAM MOTIONS FOR HIGH-SPEED SEMI-RIGID FOLLOWER CAM SYSTEMS

1988 ◽  
Vol 12 (3) ◽  
pp. 121-128 ◽  
Author(s):  
P.S. GREWAL ◽  
W.R. NEWCOMBE
Keyword(s):  
High Speed ◽  
Dynamic Performance ◽  
Poor Performance ◽  
Performance Criteria ◽  
Vibrational Response ◽  
High Speeds ◽  
Speed Performance ◽  
Cam Profile ◽  
Torque Values ◽  
Profile Errors

A study is presented on the comparison of all the popular cam motions based on a refined dynamic model which takes into account the effects of cam profile errors and most of the important factors that influence the dynamic performance for a semi-rigid follower cam system. A stochastic model is developed to simulate the input signal resulting from the cam motion, including the deviations due to profile errors. The performance criteria comprise the vibrational response at the follower and the dynamic characteristics at the cam. It has been established that, at high speeds, it is not the vibrational behaviour, but the follower tendency to jump and the maximum contact force and cam torque values which determine the dynamic performance. The Modified-Sine, Simple Harmonic and 3-4-5 Polynomial motions have been shown to exhibit superior high speed performance compared to that of the popular Cycloidal and Modified Trapezoidal motions. Higher-order Polynomial motions give very poor performance at high speeds.

Design for Boost DC-DC Converter Controller Based on State-Space Average Method

2014 ◽  
Vol 945-949 ◽  
pp. 2867-2870
Author(s):  
Shi Su ◽  
Jia Quan Yang ◽  
Jing Xi Zou ◽  
Wen Bin Zhang
Keyword(s):  
Mathematical Model ◽  
State Space ◽  
Average Method ◽  
High Performance ◽  
Closed Loop ◽  
Dynamic Performance ◽  
Boost Converter ◽  
Closed Loop System ◽  
New Methods ◽  
The Mathematical Model

In the process of designing high performance switch power, need to establish the accurate mathematical model of converter. The DC/DC converter generally has the characteristics of nonlinear, multimodal, time-varying, so need to use new methods to study it. The work of this paper aimed at non isolated DC / DC converter, established the mathematical model of Boost converter circuit by using the state space average method. Then design the closed-loop PI controller based on the Boost converter model, the closed-loop system has good static and dynamic performance, to meet the requirements of use.

scholarly journals Theoretical and Experimental Analysis of Dynamic Characteristics for a Valve Train System

Sensors ◽  
2021 ◽  
Vol 21 (19) ◽  
pp. 6328
Author(s):  
Bo Hu ◽  
Yunzhe Li ◽  
Lairong Yin
Keyword(s):  
High Speed ◽  
Dynamic Performance ◽  
Industrial Applications ◽  
Valve Train ◽  
Dynamic Responses ◽  
Engine Vibration ◽  
High Speeds ◽  
Proposed Model ◽  
Gyroscopic Effects ◽  
Train System

The valve train is one of the main sources of engine vibration, and its dynamic performance is crucial for output power and fuel consumption. The flexibilities of slender bars and beams should be emphasised in the design of valve trains to develop high-power and high-speed engines with industrial applications. A flexible dynamic model of a valve train system is proposed. In the proposed model, the components, except the cam and gear bodies, are modelled as flexible bodies with multidirectional deformations. The gyroscopic effects of the camshaft, cams and gear discs are also considered to predict dynamic responses at high speeds accurately. Gear meshing, the friction of the cam–tappet pair, the centrifugal force of the cams and valve clearance are also considered. Experiments on housing vibration and pushrod stress are conducted to validate the proposed model. Results show that the proposed model can predict the dynamic stress of the flexible components well and predict the trend shown by the housing vibration. The proposed model shows that excessive cam rotation speed and valve clearance will cause intense bounce and jump phenomena. The proposed model can be an important reference for designing engine work speed, adjusting valve clearance and improving component durability.

Optimizing Dynamic Performance of High-Speed Road Vehicles Using Aerodynamic Aids

2016 ◽  
Author(s):  
Tushita Sikder ◽  
Saurabh Kapoor ◽  
Yuping He
Keyword(s):  
High Speed ◽  
Dynamic Performance ◽  
Lateral Stability ◽  
Road Vehicles ◽  
Ansys Fluent ◽  
The Road ◽  
High Speeds ◽  
Air Stream ◽  
High Dependency ◽  
Drag And Lift

This paper focuses on the effects of aerodynamic aids on the lateral and longitudinal dynamics of high-speed road vehicles. Aerodynamic aids, such as spoilers, can reduce drag to improve vehicle’s fuel economy and acceleration performance. On the other hand, aerodynamic aids can be utilized to enhance the lateral stability of the vehicle at high speeds by generating downforce or negative lift. However, the co-existence of drag and lift creates a paradox, that is, the downforce generated to improve car’s high-speed stability acts as a parasitic force on the car-body and slows down the vehicle forward speed. This paper will illustrate the juxtaposed effects of the aerodynamic forces on the lateral stability of the vehicle. Airfoils in the role of external aerodynamic aids will be examined based on their shapes, geometrical configurations, and at varying relative positions using the CFD technique. Moreover, the effects of attack angles, change in Reynold’s numbers (air stream velocities), and varying ground clearance on the lateral dynamics of the vehicle will be analyzed using numerical simulations with ANSYS FLUENT software package. The results and reliability of CFD simulations has a high dependency on the size of the grid, thus the aim of this paper will be to ensure that the results are independent of the grid size. Selection of the optimum design will be based on performance parameters like drag and lift coefficients. The challenge posed here is to ensure the lateral stability of the vehicle while achieving high average speed. Therefore, the main goal of the study is to enhance handling capabilities of the road vehicles at high speeds while minimizing the drag.

A Statistical Study of Process Variables to Optimize a High Speed Curtain Coater: Part I

TAPPI Journal ◽  
2009 ◽  
Vol 8 (1) ◽  
pp. 20-26 ◽  
Author(s):  
PEEYUSH TRIPATHI ◽  
MARGARET JOYCE ◽  
PAUL D. FLEMING ◽  
MASAHIRO SUGIHARA
Keyword(s):  
Boundary Layer ◽  
Experimental Design ◽  
High Speed ◽  
Statistical Study ◽  
Process Variables ◽  
High Speeds ◽  
The Stability ◽  
Air Removal ◽  
Removal System

Using an experimental design approach, researchers altered process parameters and material prop-erties to stabilize the curtain of a pilot curtain coater at high speeds. Part I of this paper identifies the four significant variables that influence curtain stability. The boundary layer air removal system was critical to the stability of the curtain and base sheet roughness was found to be very important. A shear thinning coating rheology and higher curtain heights improved the curtain stability at high speeds. The sizing of the base sheet affected coverage and cur-tain stability because of its effect on base sheet wettability. The role of surfactant was inconclusive. Part II of this paper will report on further optimization of curtain stability with these four variables using a D-optimal partial-facto-rial design.

RED CUT COBALT

Alloy Digest ◽  
1980 ◽  
Vol 29 (8) ◽  
Keyword(s):  
Fracture Toughness ◽  
Cast Iron ◽  
High Speed ◽  
Elevated Temperatures ◽  
High Speed Steel ◽  
Heat Treating ◽  
High Speeds ◽  
Red Hardness ◽  
Nonferrous Alloys ◽  
Cutting Point

Abstract RED CUT COBALT steel is made by adding 5% cobalt to the conventional 18% tungsten -4% chromium-1% vanadium high-speed steel. Cobalt increases hot or red hardness and thus enables the tool to maintain a higher hardness at elevated temperatures. This steel is best adapted for hogging cuts or where the temperature of the cutting point of the tool in increased greatly. It is well adapted for tools to be used for reaming cast-iron engine cylinders, turning alloy steel or cast iron and cutting nonferrous alloys at high speeds. This datasheet provides information on composition, physical properties, and hardness as well as fracture toughness. It also includes information on forming, heat treating, and machining. Filing Code: TS-367. Producer or source: Teledyne Vasco.

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