Parametric Excitation of Collapsible Latex Tubes
In 1985, Liu and Ding (1989) made an experiment of collapsible tubes containing a pulsatile flow. A latex tube is sealed up in a plexiglass chamber. If the transmural pressure (TP) of...
Dynamic Behavior of a Non-Linear Cable Truss
The equations of motion of a geometrically non-linear cable truss are presented. The behavior of the truss subject to harmonic excitation is studied....
Cumulants of the Nonlinear Combination of Independent Random Variables
A random variable of interest is often the sum of linear or nonlinear combinations of many independent random variables. In calculating the statistics of this random sum, advantages of...
Response of Nonclassically Damped MDOF Systems to Nonstationary Random Excitation
A procedure for calculating the dynamic response of a nonclassically damped multi-degree-of-freedom (MDOF) system to nonstationary non-white vector-valued random excitation is developed...
Voltage Regulator Influence on Generator System Stability
During initial startup of a generator system, it is not uncommon to witness generator voltage instability. Most of the time, the solution is reduced to returning the stability control...
Varying Generator Excitation to Control Draft Tube Surge
The Bureau of Reclamation recently experimented with varying the excitation applied to a hydroelectric generator to control power swings caused by draft tube surging in a Francis turbine....
Accuracies of Lysimeter Data Acquisition Systems
Electronic dataloggers are integral parts of most weighing lysimeter systems. Dataloggers supply excitation voltages to lysimeter load cells and measure resulting voltage signals. Resolution...
A New Approximate Solution Technique for Random Vibration of Hysteretic Systems
Approximate probability densities are obtained for the response of hysteretic systems under Gaussian white-noise excitations. The method of analysis is applicable to either bilinear or...
Response and Reliability Analysis of Duffing Oscillators Subject to Narrow Band Stationary Gaussian Excitations
Methods are developed for estimating the probability of oscillations on the lower and upper stable branches of the input-output amplitude relationship for a Duffing oscillator subject...
Mean Square Stability of Linear Gyroscopic Systems Under Combined Harmonic and Stochastic Excitations
This paper examines the mean square stability of linear gyroscopic systems under both harmonic and stochastic parametric excitations. The intensities of both excitations and correlation...
Analysis of Nonstationary Random Vibrations
Nonstationary random vibrations occur in structural mechanics as well as in vehicle dynamics. Very often the nonstationary excitation process can be modelled as stationary white or colored...
Active Control of Structures Under Stochastic Base Excitation with a Predominant Frequency
Active control of structures under stochastic base excitation is investigated. The synthesis of an active control system discussed in the study is based on the use of stochastic control...
Aerodynamic Methods for Mitigating Wind-Induced Building Motions
Excessive wind-induced motions of tall buildings most frequently result from vortex shedding induced across-wind oscillations. This form of excitation is most pronounced for relatively...
Bonneville I Powerhouse Station Service Unit Rehabilitation
This paper presents the work being done towards the rehabilitation of the Bonneville I station service unit. The rehabilitation of this unit includes a generator rewind, excitation system...
Retrofitting of Hydro Electric Generators with Bus Fed Solid State Excitation Systems
The Northern Hydro Division has completed retrofitting the excitation systems on 22 generating units ranging in output from 1 to 95 MWatts. The Big Creek Hydro Project upgraded these systems...
Understanding Generator Static Excitation System
This paper explains some of the basic terms and features associated with a static excitation system (SES) to enable non-specialists to specify it according to their requirements. A simple...
Characteristics of Nonstationary Response of Linear Systems
A new formulation for the statistics of the response of linear systems to nonstationary excitation is developed. Both the process and its envelope are examined and exact statistics are...
One Solution for Different Stochastic Systems
It is shown that different dynamic systems under different sets of random excitations can share an identical probabilistic solution. Such systems are said to be stochastically equivalent,...
A Probabilistic Comparative Study of Various Base Isolation Systems?Nonstationary Earthquake Excitation
A probabilistic comparative study of various base isolation systems is carried out. The laminated rubber bearing with and without lead plug, the resilient-friction, and the EDF base isolation...
Performance Consideration for Selecting a Static Excitation System
Many hydropower plants today are being upgraded with new static exciter/regulator systems to replace the old existing rotary exciters. One type of system is the semi-inverting system where...
Return to search