Knowles Lecture

Friday, January 27, 2012
Beckman Institute Auditorium

The 3rd annual James K. Knowles Lecture and Caltech Solid Mechanics Symposium was held on Friday, January 27, 2012, in the Beckman Institute Auditorium. The James K. Knowles Lecture by Richard D. James, University of Minnesota, will be followed by the Solid Mechanics Symposium with presentations by current Caltech graduate students and postdocs.

The Lecture and Symposium are in memory of James K. Knowles, William J. Keenan, Jr. Professor of Applied Mechanics, Emeritus, who passed away on November 1, 2009. He is well known for his research contributions to the theory of nonlinear elasticity and the mathematical theories of materials and structures. Dr. Knowles inspired and influenced generations of students and scholars and authored over one hundred journal publications, as well as a textbook for graduate students entitled Linear Vector Spaces and Cartesian Tensors (Oxford University Press).

The Lecture and Symposium will be held annually and are made possible by the Division of Engineering and Applied Science and the support of family, friends and colleagues through donations to the James K. Knowles Memorial Fund.

James K. Knowles Lecture

Richard D. James, University of Minnesota

Materials for the Direct Conversion of Head to Electricity

There are enormous reservoirs of energy stored on Earth at small temperature differences, including natural sources such as the temperature difference between ocean (~0°C) and ambient (-40° to -20° C for most of the year) in the arctic, and man-made sources like the waste heat from power plants and computers. The conversion of these to useable forms of energy challenges basic thermodynamic reasoning. Any such conversion device is of low efficiency, but is efficiency relevant when one is not paying for the heat? Some heat engines are highly efficient, but their ability to absorb significant amounts of heat in a reasonable period of time is limited. We present a new concept for the direct conversion of heat to electricity using phase transformations in multiferroic materials. Even though the concept involves neither significant applied stress nor significant shape change, mechanics plays the key role, as the reversibility of these phase transformations apparently rests on an issue of elastic compatibility.

Messor and Russell J. Penrose Professor at the University of Minnesota. He has a Sc.B. in Engineering from Brown University and a Ph.D. in Mechanical Engineering from the Johns Hopkins University. He has authored or co-authored some 100 articles, has given 35 plenary and named lectureships, and was awarded the Humboldt Senior Research Award (2006/7), the Warner T. Koiter Medal from ASME (2008), the William Prager Medal from the Society of Engineering Science, and the Brown Engineering Alumni Medal (2009). James' current research concerns the study of "Objective Structures," a mathematical way of looking at the structure of matter, and the direct conversion of heat to electricity using phase transformations in multiferroic materials.