Dr. Sergei Aleksandrovich Ivanenko has tragically died 24 September 2003 at the age of 49.

He graduated from Moscow Institute of Physics and Technology in 1977. His scientific carrier started in the Computing Center of Russian Academy of Sciences 25 years ago in the famous group of academician N.N. Moiseev. During last years Ivanenko was a head of division for modeling of environmental flows in Computing Center. Ivanenko was one of the most prominent figures in Russian grid generation community. In 1988 at the time of domination of finite difference mapped grid generation methods he introduced the pioneering concept of barrier variational grid generations methods guaranteeing construction of nondegenerate grids. At that time he also introduced the concept of grid untangling, i.e. construction of valid grid from bad initial guess via node movement. Both these notions now became quite common and entered engineering practice. In mid-nineties he made pioneering work on shape optimization and untangling of hexahedral grids.

He made deep contributions to theory and practice of adaptive numerical simulation methods, in particular related to robust moving adaptive grid methods for gas dynamics and environmental flows. One of his major goals was to attract attention of pure mathematicians to grid generation problems. One of the results was his work on the theory of globally invertible spatial maps jointly with geometer and topologist N.A. Bobylev, who tragically died in December 2002. During last years Ivanenko enjoyed international recognition and was lecturing in Russia and around the globe. His new book on grid generation methods was practically finished. Sergei Ivanenko was always full of life and energy, with fine sense of humour, brilliant story teller. He has amazing ability to attract and unify quite different people.

His sudden death came as a real shock to his friends and colleagues. We will miss him.

Robert Schneiders