文摘
We investigate a two-dimensional parameter-space of the Baier–Sahle flow, which is a mathematical model consisting of a set of n autonomous, four-parameter, first-order nonlinear ordinary differential equations. By using the Lyapunov exponents spectrum to numerically characterize the dynamics of the model in the chosen parameter-space, we show that for class="mathmlsrc">class="formulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0960077915004026&_mathId=si9.gif&_user=111111111&_pii=S0960077915004026&_rdoc=1&_issn=09600779&md5=e98a5b9e1f544bab49b0c7bd1b4f0fcc" title="Click to view the MathML source">n=3class="mathContainer hidden">class="mathCode"> it presents typical periodic structures embedded in a chaotic region, forming a spiral structure that coils up around a focal point while period-adding bifurcations take place. We also show that these structures are destroyed as n is increased, as well as we delimit hyperchaotic regions with two or more positive Lyapunov exponents in the investigated parameter-space, for n greater than 3.