Resumen
Thermoyphons, in the engineering literature, is a device composed of a closed loop containing a
fluid who motion is driven by several actions such as gravity and natural convection. In this work we consider a viscoelastic
fluid described by the Maxwell constitutive equation. Their dynamics are governing for a coupled
dfferential nonlinear systems, and in several previous work we show chaos in the fluid. This work is, a generalization of Proposition 2 in A. Jiménez-Casas 2018], and also in some sense, a generalization of some previous results on standard (Newtonian) fluids obtained by
A. Rodrguez-Bernal and E.S. Van Vleck [21,22], when we consider a viscoelastic fluid.
