Presented in International Conference on Mathematical Fluid Mechanics a Tribute to Giovanni Paolo Galdi, on the Occasion of Professor Galdi’s 60th Birthday, IST/UTL, Estoril, May 21-25, 2007.RELATED PUBLICATION: L. CONSIGLIERI, The (p-q) coupled fluid-energy systems, in Advances in mathematical fluid mechanics. Dedicated to Giovanni Paolo Galdi on the Occasion of his 60th Birthday. (Lisbon, 2007). Eds. R. Rannacher and A. Sequeira, Springer-Verlag, Berlin Heidelberg 2010, 177--190.