**George Batchelor** was the son of George Conybere Batchelor and Ivy Constance Berneye. He attended Essendon and Melbourne high schools. He completed his secondary school education in 1937 after exceptional achievements. He the entered the University of Melbourne to study mathematics and physics.

Batchelor graduated from Melbourne University in 1940, continuing to obtain a Master's Degree in 1941. Due to World War II, he then undertook work for the war effort at the Australian Aeronautical Research Laboratory. His work there was on fluid flow problems in aircraft engines. The work he undertook at this time gave him an interest in fluid dynamics which would become the topic on which he did research for the rest of his life. In fact it was more specific than that, for the applications he studied in the Aeronautical Research Laboratory convinced him that turbulence was the most important problem to attack in aerodynamics.

At this time Batchelor wrote his first paper, which appeared in 1944, *Interference in a wind tunnel of octagonal section* which gave a mathematical deduction of the interference on a model of small wing span suspended at the centre of a tunnel of octagonal section. The actual octagonal shape of the rectangular wind tunnel was, not surprisingly, that of the Australian Council's Division of Aeronautics, Melbourne. Also in 1944 his paper *On the hydrodynamic resistance* was published.

The leading British expert on turbulence was Geoffrey Taylor, and Batchelor wrote to him at the Cavendish Laboratory in Cambridge offering to work for him. Batchelor and his colleague Alan Townsend arranged funding to allow them to undertake research with Geoffrey Taylor. Then [3]:-

... in January1945, together with his wife, Wilma, also of Melbourne, Batchelor embarked on a marathon ten-week voyage via New Zealand, the Panama Canal and New York, and thence in a convoy of80ships across the Atlantic to reach Cambridge.

Arriving in Cambridge Batchelor and Townsend discovered that Geoffrey Taylor was no longer interested in undertaking his own turbulence research, but he was happy to supervise them. Batchelor began to examine Kolmogorov's approach to turbulence and in 1946 he presented his interpretation of Kolmogorov's work to the Sixth International Congress for Applied Mechanics in Paris.

Batchelor was elected a Fellow of Trinity College, Cambridge in 1947 and in the following year he was awarded his doctorate and became a Cambridge University lecturer. He continued to produce work of great importance in fluid dynamics. For example he wrote a paper in 1946 developing the theory of homogeneous axisymmetric turbulence following the methods of von Kármán. He addressed the Seventh International Congress for Applied Mechanics in 1948, speaking on *Recent developments in turbulence research*. He wrote a joint paper with Geoffrey Taylor in 1949 *The effect of wire gauze on small disturbances in a uniform stream*.

Batchelor was awarded the Adams Prize by the University of Cambridge in 1951. He wrote a research monograph *Homogeneous Turbulence* in 1953 which proved definitive. Then, in 1956 with Townsend as a joint author, he wrote *Turbulent diffusion*. Lin, reviewing this joint paper of Batchelor and Townsend wrote:-

As is well-known in this difficult subject of turbulent diffusion, most of the theoretical developments merely help to provide a framework for the interpretation of measurements, and do not provide definite deductions. The authors, however, have managed to collect a number of cases where a definite contact has been established between theory and experiment.

Certainly Batchelor stamped his personality on the Cambridge Department. Hunt writes [2]:-

At the formidable seminars held at4.30on Fridays, which Batchelor instituted in1948, many crucial theoretical developments were first presented, including his own. He managed these lively occasions like a circus lion tamer, with a turn of his head and a stare at any stupidity or excessive harassment of visiting speakers.

In 1957 Batchelor was elected to a fellowship of the Royal Society of London and then in 1959 he became a Reader in Fluid Dynamics at Cambridge. At the same time he became Head of the Department of Applied Mathematics and Theoretical Physics becoming a professor of applied mathematics in 1964.

In May 1956 Batchelor founded the *Journal of Fluid Mechanics* and he edited the journal until January 1999. The paper [1] was written as a tribute to Batchelor when ended his 43 years as editor. Crighton, in [1], ascribes to Batchelor the high standing of the *Journal of Fluid Mechanics* due to his:-

... insistence not only on the highest standards of scientific work but on the highest standards of clarity and presentation in Journal of Fluid Mechanics papers.[Batchelor's]concerns over clarity of exposition are evidenced also by his own papers in Journal of Fluid Mechanics, by his celebrated textbook(still regularly reprinted), and by his trenchantly critical Journal of Fluid Mechanics book reviews(for example "This is slipshod writing and it is sheer irresponsibility to put it into print").

The "celebrated textbook" referred to in this quotation is *An Introduction to Fluid Dynamics* (1967). We should also mention his major task in editing the papers of Geoffrey Taylor which appeared in four volumes, 1958, 1960, 1963, and 1971. He also wrote *The Life and Legacy of G I Taylor* which was published in 1996.

Pedley, in [4] gives this insight into Batchelor's character:-

As a scientist, George was admired for the depth and precision of his thinking. To students and colleagues, he was a rock on which they could rely for clear guidance, given with warmth and humour. As an administrator, he kept his clear vision while attending meticulously to detail.

Among the many honours which Batchelor received was election to the American Academy of Arts and Sciences (1959), to the Polish Academy of Sciences (1974), to the French Academy of Sciences (1984), and to the Royal Society of London in 1959 and a Fellow of the Australian Academy of Sciences (1989). He was awarded honorary doctorates by Grenoble (1959), Technical University of Denmark (1974), McGill (1986), Michigan (1990), Melbourne (1994), and Stockholm (1995). In addition he won numerous prizes and medals for his outstanding work. He was awarded the Agostinelli Prize by the Accademia Nazionale de Lincei in Rome in 1986, the Royal Medal from the Royal Society of London in 1988, the Timoshenko Medal from the American Society of Mechanical Engineers in 1988, and the Taylor Medal from the Society of Engineering Science in 1997.

**Article by:** *J J O'Connor* and *E F Robertson*