Dear researchers
As the matter of fact, when we use dynamic model while simulating the quasi-static problem, inertial forces are there which are not (or negligible) present in quasi-static. I want to know what is the criteria or extent to which we are confident that process is still quasi-static?
I will be thankful if proper reference be cited.
Thanks
As I know,we can't use "dynamic analysis" option while performing quasi-static analysis,because mass and time are important in dynamic analysis. you should do several nonlinear static analysis consecutively.
Hope it helped
From the question it is not cleared that which system you are analyzing?
Basically dynamical systems are governed by the position dependent restoring forces, acceleration dependent inertia forces, velocity dependent dissipative forces, dry friction forces (magnitude independent of velocity but direction depends on velocity or displacement), displacement dependent dissipative forces (due to material or hysteretic damping).
It is appropriate to perform the quasi–static analysis with cyclic input (usually harmonic excitation) and primarily it is used for identification of system parameters. When the system is excited by very low frequency and small amplitude, the position, velocity and acceleration dependent components are absent or negligible and only friction and static forces are present. Then if amplitude is increased by maintaining the low frequency, the position dependent component appears.
But how one can be sure that the process is near quasi–static? The answer is partially given by my conference paper (Analysis of Heat Transfer Effects on Spring Characteristic of Hydro-Pneumatic Struts) which you can find on RG.
First you find the lowest and highest time constants (tau1 and tau2) of the system. As a starting point use excitation frequency w(rad/s) < 1/tau2 , also tau2 helps to decide the total simulation time T > 2*tau2. The tau1 helps to determine the sampling frequency or time step for simulation, ts(sec) < tau1/5.
Hope this helps.
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