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PERSONAL NEWS

invented an ingenious method of di- the gist of what had been taught in the NAL – a facility that now may well be
rectly measuring the friction drag on a classroom. the most well-equipped blowdown tun-
surface by letting a small strip of it – To anyone who walked into the labo- nel in the world. Simultaneously his
about a millimeter wide – float, and ratory that he set up at the Institute, one research in fluid dynamics continued:
measuring its effective deflection thing that caught immediate attention he and his students made pioneering
against the resistance of a spring by was that every thing looked different, investigations in the intriguing phe-
electronic methods, using a null tech- and worked well. The laboratory man- nomenon of boundary layer transition,
1
nique . These results appeared in vari- aged to convey an impression of both as the flow goes from a smooth, laminar
ous books of the time, including the science and engineering; it had 100 hp state to the more common eddying,
first edition of the English translation compressors running wind tunnels, as irregular, turbulent state; they also stud-
(from German, published in 1955) of well as lenses and galvanometers meas- ied reverse transition or relaminiariza-
Schlichting’s book Boundary Layer uring what was going on in those tun- tion, as the flow (under certain
Theory, the first on the subject. They nels. In a very real sense I think conditions) reverts (to everybody’s
have been faithfully reproduced in the Dhawan established, at IISc and – by amazement at the time) to the laminar
many editions the book has gone example – elsewhere in the country, a state. Also studied were wall jets, axi-
through over the last fifty years, includ- tradition of scientific research on engi- symmetric bodies, three-dimensional
ing the eighth published in 1999 (ref. neering problems. His laboratory also boundary layers, base flows, separation
2). had a variety of little devices, rigged up bubbles, transonic flows and so on. It
At IISc, which he joined as a Senior by him with great and obvious pleasure, was almost as if Dhawan wanted to set
Scientific Officer in 1951 (he became to make things a bit easier for the ex- up a base from which any worthwhile or
Professor and Head of the Department perimenter. Among these ‘gizmos’, as important topic in aeronautical fluid
of Aeronautical Engineering in 1955, he loved to call them, I remember a dynamics could or would be studied.
and Director in 1962), he built the first pretty little thing for electroplating 5 He was the father of experimental
supersonic tunnels in the country. (The micron tungsten wires with copper, so fluid dynamics research in India, and
very first was a tiny tunnel with a test that they could later be soldered for indeed was in many ways the first engi-
section of 1 cm · 1 cm or so, running making hot wire probes – I started my neering scientist of the country.
on compressed air stored in two war- life in the laboratory, like so many stu- He summarized all of this research in
surplus oxygen tanks from a Dakota.) I dents of fluid dynamics everywhere in a lecture which he gave at the First
first met him when I joined the Institute the world at that time, struggling to Asian Congress of Fluid Mechanics,
as a student in 1953. That is now nearly make these fragile probes for wind tun- held in Bangalore during 8–13 Decem-
fifty years ago, but my recollections of nel measurements of fluctuating veloci- ber 1980 (ref. 3). And these Asian Con-
early encounters with him are still ties in turbulent flows. I still recall gresses, growing stronger with each
vivid. I recall a tall, handsome, young Dhawan teaching me to make these meeting, were again something that
man who would jump out of his sporty probes, telling me about the ritual one would not have prospered without his
little MG car, wearing a red shirt and a had to follow – ‘like doing pooja’, he moral and material support.
broad smile, racing across the stair-case would say. The fine wires we needed There were two outstanding features
in the Department and cheerfully saying for these probes were not easily avail- of Dhawan’s philosophy in research.
‘Good morning’ as he stepped into the able, and Dhawan had obtained from his First, it was carried out at low cost, with
class room. Dhawan brought to the In- friends in the United States various bits ingenious development or adaptation of
stitute an element of youth, freshness, of platinum and tungsten wire which whatever materials, skills and instru-
modernity, earnestness and Californian came stuck on the back of letters written mentation were available at the time;
informality that captivated the students to him: we used to hoard them like mi- second, the basic research areas investi-
and many colleagues. In short, he was a sers. gated in his laboratories were all in-
I vividly recall how the 1 inch ·
star on the campus. spired in some way by the problems
Students liked his classes very much 3 inch wind tunnel in the High Speed faced by the newly-born aircraft indus-
indeed, and for a variety of reasons; the Aerodynamics Laboratory was cali- try of the country (which he had known
first of these was, as I have already brated, with the help of all hands that from the year he had spent on the work-
remarked, Dhawan’s general cheerful- could be mustered at any given time, to shop floors before he went to the US).
ness in his approach to the subject as open valves, ring bells, take readings, In later years he constantly sought to
well as to the students. He took his click cameras, etc.: it was all very dra- promote the development of this indus-
teaching very seriously, and supplied matic to me at the time. (Not that the try at the higher levels of policy and
his classes with plenty of notes, data number of people so mustered was very management, and persuaded HAL to
sheets, diagrams and so on. He worked large: the Department was still small start a division for space projects.
hard on all these – one would often see then.) He also led a pilot project for the In 1972 Dhawan was appointed
him in his office late at night – and he huge facilities that later came up at the Chairman of the Space Commission and
expected the students to work just as National Aeronautical Laboratory (now of the Indian Space Research Organiza-
hard – which many of them cheerfully the National Aerospace Laboratories, tion (ISRO), and Secretary to the Gov-
did. Another reason for the great popu- NAL) in Bangalore. The students and ernment of India in the Department of
larity of his classes – last but not least, colleagues he worked with at IISc went Space. It was an inspired appointment.
as they say! – was that he was generous on to establish and run the National The Indian space programme owes its
with his grades if the student had got Trisonic Aerodynamic Facility at birth to the vision of Vikram Sarabhai,
CURRENT SCIENCE, VOL. 82, NO. 2, 25 JANUARY 2002 223