Global dynamics examples

For the global dynamics governing the rubbery/terminal relaxation, the thermorheological complexity of the components is one of the most prominent features. In PI/PVE blends associated with just a moderate dynamic asymmetry of the components, respective components exhibit very minor complexity and behave similarly to the components in chemically uniform blends such as PI/PI blends, as revealed from rheo-optical and dielectric studies. (PI chains have the type-A dipole so that their global motion is dielectrically detected.) The entanglement relaxation in the PI/PVE blends appears to occur through the mechanisms known for the chemically uniform blends, for example, through the reptation and constraint release (CR)/ dynamic tube dilation (DTD) mechanisms. 

Figure 1,8, for example, plots the probability that a cell has value 1 at time t4-l - labeled Pt+i - versus the probability that a cell had value 1 at time t -labeled Pt - for a particular four dimensional cellular automaton rule. The rule itself is unimportant, as there are many rules that display essentially the same kind of behavior. The point is that while the behavior of this rule is locally featureless - its space-time diagram would look like noise on a television screen - the global density of cells with value 1 jumps around in quasi-periodic fashion. We emphasize that this quasi-periodicity is a global property of the system, and that no evidence for this kind of behavior is apparent in the local dynamics. 

It is also interesting to examine the global gas dynamic structure of upward propagating flames. Figure 3.1.6 gives an example of the global velocity field for the lean limit methane flame in the flame coordinates. The velocity distributions for all near limit flames studied share certain features. The central part of the bubble-shaped flame is... 

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