Energy and the Environment: Basis in Thermal Sciences

Transcription

1 Energy and the Environment: Basis in Thermal Sciences [Thermodynamics of Heat and Fluid Flow Configurations] Adrian Bejan J. A. Jones Professor of Mechanical Engineering

2 The evolution of design: Power generation increases Efficiency increases

3 Why do humans need power? For the same reason that animals and river basins need power: to move mass on the Earth s surface Constructal theory of animal locomotion: 1 Vopt ~ M1/ 6 t opt ~ M 1/ 6 F ~ 2Mg Wmin / L ~ Mg

4 Mass flows nonuniformly: - river basins - animal migration - human dynamics 2002 Example: Persistent contrail coverage 2050

5 The Constructal Law of Configuration Generation in Nature: For a finite-size flow system to persist in time (to survive) it must evolve such that it provides easier access for the currents (1996) Geophysics Biology Engineering Social dynamics

6 Globalization and Sustainability: Mass will continue to move nonuniformly, through established channels. Energy (exergy, fuel) consumption will continue to be distributed nonuniformly. The best way to bring the less advanced areas into the flow of things, is to allow the global vascularization (goods, people, energy, information) to bathe the whole earth. Freedom is good for design: freely changing vascular patterns will attach the lagging areas to the big branches.

7 Theory returns the favor to engineering The future belongs to the vascularized (Lorente, 2006). Electronics cooling Fuel cells Smart materials self healing self cooling Svelteness (compactness) Miniaturization = nanotechnology + constructal design

8 Societal relevance and impact Example: Treehugger magazine, Dec Constructal Theory: Sustainability By Tim McGee, Los Angeles on SCIENCE & TECHNOLOGY (SCIENCE) Sustainability has become a key concept to solving global resource and environmental issues. Several concepts have emerged in the past few decades. Biomimicry inspires and provides a way for us to adopt examples of evolved systems. Cradle-to-Cradle design provides a goal for enriching industrial systems. Constructal theory gives us the key for understanding the nature of sustainable technology. These ideas have come at a unique time in our history when, as a society, we are looking at all scales to determine how to better manage our impact on Earth. Read on to see how constructal theory fits into the new paradigm.

9 Invited Lecturers 2006 & 2007: A community of scholars is developing worldwide: Sylvie Lorente INSA Toulouse Heitor Reis University of Evora Antonio Miguel University of Evora Stephen Périn NeoSys, Paris Tim Birkland National Science Foundation Ralph Michaels Eduardo Brondizio Indiana University Tim Pennings Hope College Roland Minton Roanoke College Franca Morroni DEXIA Asset Management, Brussels Timothy McGee Treehugger Magazine Jean-Christophe Denaes University of Quebec, Montreal Cyrus Amoozegar John Angle Inequality Process Institute Paul Ossenbrugen University of New Hampshire Pat Longstaff Syracuse University Gloria Gonzalez-Rivera University of California, Riverside Sadanand Srivastava Bowie University William Wallace Rensselaer Polytechnic Institute Sandra Schneider National Science Foundation Rex Oleson University of Central Florida John Staddon Anthony Oberschall University of North Carolina, Chapel Hill Carter Butts University of California, Irvine Miruna Petrescu-Prahova University of California, Irvine Lorien Jasny University of California, Irvine Steve Sacco Adrian Bejan Gilbert Merkx Edward Tiryakian Ken Land

10 References 1. A. Bejan, Shape and Structure, from Engineering to Nature, Cambridge University Press, Cambridge, UK, H. Reis, Constructal theory: from engineering to physics, and how flow systems develop shape and structure. Appl. Mech. Reviews Vol. 59, 2006, pp A. Bejan and S. Lorente, Constructal theory of generation of configuration in nature and engineering, Applied Physics Reviews, Journal of Applied Physics, Vol. 100, 2006, A. Bejan and G. W. Merkx, eds., Constructal Theory of Social Dynamics, Springer-Verlag, New York,