My involvemcnt with Pijush Kundu’s FluidMechunics first began in April 1991 with a letter from him asking mc to consider his book for adoption in the first year graduatc courSe 1 had been teaching for 25 ycars. That started a correspondence and, in fact, I did adopt the book lor the following acadcmic ycar. The correspondence related to improving the book by enhancing or clarifying various points. T would not have
taken the time to do that iT I hadn’t thought this was thc best book at the first-year graduate level. .By the end of that ycar we werc alrcady discussing a swond edition and whether 1 would have a role in it. By early 1992, howcvcr, it was clcar that T had a crushing administrative burden at the University or Pennsylvania and could not undertake any time-consuming projects for the next several years. My wile and 1 met Pijush and Shikha for the first time in December 1992. They were a charming, erudite, sophisticated couple with two brilliant children. We immediately relt a bond orwarmth and €riendship with them. Shikha was a Leacher like my wife so the four of us had a great deal in common. A couple or years later we were shocked to hear that Pijush had died suddenly and unexpectedly. It saddened me gcatly bccause I M been looking forward to working with Yijush on the second edition after my term as department chainnan ended in mid-1997. For the next year and a half, howcvcr, scrious family health problems detoured any plans. Discussions on this cdition resumed in July ol 1999 and wcrc concludcd in the Spring or 2000 when my work really started. Thishook remains thc principal work product of Pijush K. Kundu, especially the lengthy chapters on Gravity Waves, Instability, and Geophysical Fluid Dynamics, his areas or expertise. I have addcd ncw material to all of the other chapters, often providing an alternative point of view. Specifically, vcctor field derivatives have been generalized, as have been streamfunctions. Additional material has been added to thc chaptcrs on
laminar flows and boundary layers. The trcatmcnt of one-dimensional gasdynamics has been extended. Morc problems have been added to most chapters. ProIessor Howard H. Hu, a recognized expert in computational fluid dynamics, graciously provided an cntircly new chapter, Chapter 1 1, thcrchy providing the student with an entree into this cxploding new field. Both finite diffcrcncc and Gnite element methods arc introduced and a delailed worked-out cxamplc of each is provided. 1 have becn a studcnt 01 fluid mechanics since 1954 when I entered college to study aeronautical engineering. I have been teaching fluid mechanics sincc 1963 when
I joincd thc Brown University faculty, and I have been teaching a course corresponding to this book since moving to thc University orPennsylvania in 1966. I am most grdtCfUl 10 two of my own tcahers, Prolessor Wallace D. Hayes (191 8-2001), who expressed fluid mechanics in the clearest way I have ever seen, and Professor Martin D. Kruskal, whose use of mathematics to solve difficult physical problcms was developed to a high art form and reminds me of a Vivaldi trumpet concerto. His codification of rules of applied limit processes into the principles of “Asymptotology” remajns with me today as a way to view problems. T am grateful also to countless students who asked questions, forcing me to rethink many points.
The editors at Academic Press, Gregory Franklin and Marsha Filion (assistant) have been very supportive of my efforls and have tied to light a fire under me. Since this edition was completed, I found that thcrc is even more new and original material I would like to add. But, alas, that will have to wait for the next edition. The new figures and modifications of old figures were donc by Maryeileen Ranford with occasional assistance from the school’s software expert, Paul W. Shaffer. I greatly appreciate their job well done.
Ira M. Cohen