Editorial

Citation

Voller, V. (1999), "Editorial", International Journal of Numerical Methods for Heat & Fluid Flow, Vol. 9 No. 3. https://doi.org/10.1108/hff.1999.13409caa.001

Editorial

Vaughan R. Voller is Professor of Civil Engineering at the University of Minnesota and also associated with the St Anthony Falls Laboratory, also at the University of Minnesota. All of Professor Voller's degrees are in applied mathematics and the general area of his research is the development of numerical methods for heat and mass transfer problems. A central theme in his research is the formulation and solution of free and moving boundary problems. He has developed many numerical solution techniques for this class of problems. These techniques have found application across a wide range of problems, including, melting and solidification of metals, filling of molds, and geo-morphology. He has published over 100 papers in the literature, principally in material engineering, mathematics and numerical journals. Professor Voller is a fellow of the Institute of Mathematics and its Application (UK) and a member of the TMS and ASEE. ÉÅKumar K. Tamma is a Professor of Mechanical Engineering at the University of Minnesota in Minneapolis. His research interests encompass the development and applicability of computational methods for multi-disciplinary thermal-structural and fluid-thermal-structural problems in the general areas of computational mechanics; finite element methods; computational structural dynamics and contact-impact; computational thermal sciences encompassing non-classical/classical models and microscale heat transfer; manufacturing applications in materials processing and prediction of residual stresses in composites manufacturing and solidification problems; and development of transient algorithms and modeling/analysis approaches for applications to large-scale computational problems and high performance computing environments. He has authored/co-authored over 150 research articles in various journals and refereed proceedings, and book chapters. Dr Tamma is a member of ASME, AIAA, the International Association for Computational Mechanics, and the US Association for Computational Mechanics.

In 1979 Professors Roland Lewis and Ken Morgan organized a conference at the University of Wales, Swansea on "Numerical Methods in Thermal Problems." This conference was the first in a successful biannual series that has done much to define and promote the use of numerical methods to solve thermal problems. This issue of the journal is devoted to a selection of works based on papers that were presented at the 10th International Conference on Numerical Methods in Thermal Problems, held in Swansea in July 1997.

A common theme of previous conferences in the series-dating back to the first conference has been the development of numerical techniques for convection problems. The first two papers in this special issue continue this tradition. P.H. Oosthuizen presents a transient study of natural convection in an enclosure driven by a stepwise periodic heat flux, and the paper by C. Nonino, G. Comini and G. Croce studies "three-dimensional flows over backward facing steps".

The early conferences of the series focussed on heat conduction issues with extensions to fluid flow and convection. Over the years as numerical solution approaches have become more refined, there has been a movement to solve problems which include all modes of heat transfer, namely, conduction, convection and radiation. This is the topic of the third paper in the issue, from I. Rupp and C. P Niguel. Numerical methods for radiation problems is also the concern of the fourth paper from J.-V. Daurelle, R. Occelli and M. Jaeger. The special point of interest in this work is the investigation of radiation problems in domains with moving boundaries.

Another common theme of previous conferences has been phase change problems. In early editions of the series the focus was on the development of numerical techniques to solve Stefan type problems. Over the years, however, this has been extended to the numerical modeling of practical problems of casting simulations. These efforts are reflected in the next three papers in this special issue. B. Sžarler and J. Mencinger present an extension of the "dual reciprocity boundary element method" in the modeling of a direct chill aluminium casting. M. M'Hamdi, H. Combeau and G. Lesoult model the continuous casting of steel and present the current state of the art in the combined heat and mass transfer modeling of solidification problems. Modeling of this nature really comes into its own when practical results are realized. The last paper, relevant to the phase change topic, by R.S. Ransing, R.W. Lewis and D.T. Gethin, shows how numerical heat transfer techniques can be used to avoid casting defects, and is an excellent example of a practical result.

The Numerical Methods in Thermal Problems Conferences have always been at the cutting edge. The last two papers in this special issue fit into this mold. J.T. Cross, I. Masters and R.W. Lewis discuss how object-oriented finite element codes can be effective in heat transfer modeling. In the final paper, due to K.K. Tamma, X. Zhou and D. Sha, a formal theory of development/evolution and characterization of generalized time discretized operators for a wide class of computational algorithms is described. Theory, that could have important consequences in continued developments towards general heat transfer transient analysis computations is presented.