This behavior could be explained, because, as the travel speed increases, the torque produced in the driving wheels decreases and consequently, so does the slip, thereby increasing the traction force to a certain limit, reaching the
critical speed. The mean rolling resistance value obtained in the field was 4.70kN (483kgf), which represents 8.40% (k = 0.08) of the total mass of the tractor.
In this study, the floating
critical speed of an aircraft wing in a subsonic fan was determined using dynamic experimental tests and numerical simulations.
When the ramping or the third method is used, it always yields the
critical speed of about 300~350 km/h, even 400 km/h.
A
critical speed analysis assuming rigid bearings with a stiffness of [10.sup.8] lb/in predicted shaft stresses at the first bending mode of 2,371 psi (Figure 28), an increase of 39% when compared to the original rotor.
Above the
critical speed, [[omega].sub.b], the voltage limit ellipse is totally included in the current limit circle [15], as illustrated in Fig.
Dr Rabi Mehta, branch chief at the US space agency's (NASA) Ames Research Center in California, outlined roughness as a factor that dictates what the
critical speed is going to be at which one gets maximum 'knuckling' of the ball when the ball is not spinning or spins very little.
Critical speed is defined as the agitator rotational speed (rpm) which coincides with its first natural frequency.
In order to explore the dynamics process with varied parameters, we put the observations in our model and then further study the influence of the competition coefficient ([[sigma].sub.12] and [[sigma].sub.21]) in case of messages propagation with low (or high)
critical speed ([alpha] and [beta]).