68th Conference of the Indian Society of Theoretical and Applied Mechanics
(ISTAM - 2023)

(An International Conference)

December 07-09, 2023

Memorial Lectures

Professor BR Seth (Professor Bhoj Raj Seth)

(27-08-1907 - 12-12-1979)

Specialization : Elasticity , Plasticity, Fluid Mechanics.

Summary : Bhoj Raj Seth obtained PhD (1934) and DSc (1937) degrees from University of London, UK and DSc (hc) from Indian Institute of Technology (IIT), Kharagpur. He was Reader, University of Delhi (1939-35); Visiting Professor, Iowa State University, USA (1949-50); Professor and Head, Department of Mathematics, IIT Kharagpur (1951-66); Visiting Professor, Mathematics Research Centre, University of Wisconsin, USA (1961-62) and Oregon State University, USA (1967-68); Vice-Chancellor, Dibrugarh University (1966-71); Visiting Fellow, IIT Delhi (1971); and Director, Birla Institute of Technology and Sciences, Pilani (1971-77).

Academic and Research Achievements: Seth's work on the theory of elasticity and plasticity and fluid mechanics is well known. His work on finite strain in elastic problems gave a second-order treatment of simple torsion, pure flexure and torsion, based on a quasi-linear stress-strain relation. He gave the first complete solution for a right-angled isosceles triangle. He described the complete solution for an eccentric hollow shaft and worked on problems of bending, vibration and stability of membranes and plates with triangular boundaries and the application of finite strain theory to these problems. Standard books like Mathematical Theory of Elasticity by Sokolnikoff and Elasticity and Plasticity by Goodier and Hodge give ample references to his work.

Other Contributions: Seth was largely responsible for the formation of Delhi University Teachers' Association. He served as Editor of the Indian Mathematical Society's publications. The extension lectures he delivered at the University of Lucknow were published as the monograph 'Two Dimensional Boundary Value Problems'.

Awards and Honours: Professor Seth won the Euler Medal by USSR Academy of Sciences (1958) and Dr BC Roy National Award (1977). He was elected Fellow of the Calcutta Mathematical Society and Indian Mathematical Society; and also President, Mathematics Section, Indian Science Congress (1955).


Prabhu Lal Bhatnagar (P.L Bhatnagar)

(8 August 1912- 5 October 1976)

Prabhu Lal Bhatnagar (8 August 1912 - 5 October 1976), commonly addressed as P. L. Bhatnagar, was an Indian mathematician known for his contribution to the Bhatnagar-Gross-Krook operator used in Lattice Boltzmann methods (LBM).

His research career started at the Allahabad University under the supervision of Prof. B. N. Prasad on summability theory but soon he joined Prof. Amiya Charan Banerjee to work in differential equations. The results of his work (with Prof. Banerji, published in Proceeding of National Academy of Sciences, 1938) are included in the book of Erich Kamke. He became interested in the area of astrophysics after coming in contact with Meghnad Saha. In 1939 he obtained DPhil degree in mathematics for his thesis titled On the Origin of the Solar System.

In 1939 he joined St. Stephen's College, Delhi on the invitation of S. N. Mukherjee and spent the next 16 years there. There he worked on the theory of white dwarfs, independently and together with Daulat Singh Kothari.

In 1952 he was invited to Harvard University as a Fulbright scholar. There he worked together with Donald Howard Menzel and Hari Kesab Singh in the field of non-linear gases. His work with the Boltzmann equation led to his well-known BGK collision model in 1954 together with Eugene P. Gross and Max Krook. It was at first extensively developed for ionized gases with many applications. These days, the BGK collision operator is essential for the recent development of lattice Boltzmann automata methods.

In 1950 he was elected fellow of Indian National Science Academy and in 1955 the fellow of Indian Academy of Sciences. In 1956 he was invited to join Indian Institute of Science as the founding Professor of the Department of Applied Mathematics. There he expanded his research area into the field of non-Newtonian fluid mechanics. Alongside to his research work he also laid down the foundation stone of the Indian National Mathematics Olympiad. For his contributions to the nation, on 26 January 1968 he was awarded the Padma Bhushan.

During the early 1960s he developed complications in the lower spinal region and was operated on in the United States. In 1969 he moved to Rajasthan University in Jaipur as Vice-Chancellor and in 1971 joined Himachal Pradesh University in Shimla as Head of the Mathematics Department. He was also member of the Union Public Service Commission and the first Director of the Mehta Research Institute (now renamed as the Harish-Chandra Research Institute).

Honors and awards: He was awarded the Padma Bhushan by the President of India on 26 January 1968. After he died on 5 October 1976 at Allahabad, the Illustrated Weekly of India paid a tribute to him through an article on him by the well-known science writer Jagajit Singh. He moved to Delhi in October as member of the Union Public Service Commission. In 1975 he accepted the post of Director of the newly created Mehta Research Institute in Allahabad. He died of a heart attack on 5 October 1976.


Professor B. KARUNES

(29 January 1925-29 June 1978)

Professor B. Karunes was born at Ghatshila in Bihar where he received his early education. He took his B.Sc, (Honours) in Civil Engineering at Glasgow University (1949) and his D.Phil. at Calcutta University (1954). In 1957-58 he went to Brown University as a Senior Fellow, and in 1968 he was on the visiting faculty of the Imperial College, London. He was elected President of the Indian Society of Theoretical and Applied Mechanics in 1971. He joined the department of Physics of Calcutta University in 1950 as a Lecturer in Classical Mechanics and moved to IIT Kanpur in 1963 as an Assistant Professor in Mechanical Engineering, where in 1964 he was promoted to a full professorship, In 1966, he joined IIT Delhi as Professor of Applied Mechanics and held important positions such as Dean of Post-Graduate Studies, Chairman of the Admissions Committee, Head of Department, and Senate nominee on the Board of Governors, IIT Delhi. He was also nominated to the Board of Governors of G.B. Pant University for two terms. He served in these positions with distinction. Professor Karunes had earned a high reputation for himself as a researcher and scholar, both within and outside the country. His diverse academic interests included areas such as Elasticity, Plasticity, Fatigue, Dynamic Deformations, Bio-Mechanics, Metal-cutting and Metal-forming. For his eminence in these fields his services as a consultant were sought by many public and private industrial concerns in the country. He published extensively in Indian and foreign professional journals and he was for a long time an advisor, referee and member of the Editorial Advisory Board for this Journal. During his career as a teacher he supervised many Ph.D. and a number of M.Tech. dissertations and today his students occupy important positions in industry and the academic world. Besides teaching and research, his interests ranged from big game hunting to classical music to theology and philosophy. He was admired and respected by his colleagues and friends also for his qualities as a human being - for his generosity, warmth of heart and compassion.


Anadi Sankar Gupta (A.S. Gupta)

(1 November 1932 - 14 June 2012)

Anadi Sankar Gupta earned his BSc (Hons) in Mathematics and MSc in Applied Mathematics from Calcutta University. In 1957 he joined the Department of Mathematics of Indian Institute of Technology (IIT), Kharagpur as Assistant Lecturer and became Professor (1968) and continued in this capacity till 1993. He received PhD (1958) as well as DSc (1966) degree in Mathematics both from IIT, Kharagpur. As a Colombo Plan Scholar, he was a Senior Visitor (1961-62) at the Department of Applied Mathematics and Theoretical Physics, University of Cambridge, England and worked with LN Howard on problems of hydrodynamic and hydro magnetic stability. He was a Visiting Professor in the Department of Mechanical Engineering and Applied Mechanics at the University of Michigan, Ann Arbor, USA (1979-81) and worked with CS Yih on the theory of laminar and turbulent buoyant plumes. Gupta is currently INSA Honorary Scientist in the Mathematics Department of IIT, Kharagpur. He became a Life Fellow of IIT, Kharagpur in 2003 for outstanding contributions and services to the Institute.

Academic and Research Achievements: At IIT, Kharagpur, Gupta taught Mathematics and Mechanics to engineering students at both undergraduate and postgraduate levels. He also taught several advanced topics in mathematics, mechanics and fluid dynamics at MSc and post-MSc levels. He initiated research programme in fluid dynamics, hydrodynamic and hydro magnetic stability, heat and mass transfer in fluid flows and made significant contributions in all these areas. His analysis on steady and transient free convection in an electrically conducting fluid past a hot surface permeated by a transverse magnetic field reveals that the field causes a reduction in surface heat flux. This result has important bearing on cooling of nuclear reactors. His studies on flow over a stretching surface have applications to polymer and metal working process. Gupta showed that homogeneous and heterogeneous chemical reaction result in a reduction of the longitudinal (Taylor) diffusion coefficient of a solute dispersed in laminar flow in a channel. While studying the stability of the free surface of a layer of a viscoelastic fluid, he found that the viscoelasticity has a destabilizing effect on the flow. He has published about 150 research articles and a book entitled Calculus of Variations with Applications (Prentice Hall, 1997). He has mentored about twelve PhD students.

Other Contributions: Gupta's research results have been cited in a large number of books and research monographs. He was President of the Annual Congress of Indian Society of Theoretical and Applied Mechanics (1985) and Annual Congress of Indian Mathematical Society (1999), and has become its Council Member (2007-09). He was on the Editorial Board of the journal Stability and Applied Analysis of Continuous Media (Italy) and Indian Journal of Pure and Applied Mathematics. Dr Gupta served as an INSA Council Member (2000-02).

Awards and Honours: Dr Gupta won SS Bhatnagar Prize (1972) and FICCI Award (1978). He received PL Bhatnagar Memorial Lecture Award of Indian Mathematical Society (1995) and Professor Vishnu Vasudeva Narlikar Memorial Lecture Award (2003) of INSA. He was elected a Fellow of National Academy of Sciences (India), Allahabad (1990).


G. I. Taylor

(7 March 1886 - 27 June 1975)

To students of physics, Taylor is best known for his very first paper, published while he was still an undergraduate, in which he showed that interference of visible light produced fringes even with extremely weak light sources. The interference effects were produced with light from a gas light, attenuated through a series of dark glass plates, diffracting around a sewing needle. Three months were required to produce a sufficient exposure of the photographic plate. The paper does not mention quanta of light (photons) and does not reference Einstein's 1905 paper on the photoelectric effect, but today the result can be interpreted by saying that less than one photon on average was present at a time. Once it became widely accepted ca. 1927 that the electromagnetic field was quantized, Taylor's experiment began to be presented in pedagogical treatments as evidence that interference effects with light cannot be interpreted in terms of one photon interfering with another photon—that, in fact, a single photon must travel through both slits of a double-slit apparatus. Modern understanding of the subject has shown that the conditions in Taylor's experiment were not in fact sufficient to demonstrate this, because the light source was not in fact a single-photon source, but the experiment was reproduced in 1986 using a single-photon source, and the same result was obtained.

He followed this up with work on shock waves, winning a Smith's Prize. In 1910 he was elected to a Fellowship at Trinity College, and the following year he was appointed to a meteorology post, becoming Reader in Dynamical Meteorology. His work on turbulence in the atmosphere led to the publication of "Turbulent motion in fluids", which won him the Adams Prize in 1915. In 1913 Taylor served as a meteorologist aboard the Ice Patrol vessel Scotia, where his observations formed the basis of his later work on a theoretical model of mixing of the air.

At the outbreak of World War I, Taylor was sent to the Royal Aircraft Factory at Farnborough to apply his knowledge to aircraft design, working, amongst other things, on the stress on propeller shafts. Not content just to sit back and do the science, he also learned to fly aeroplanes and studied the stability of parachutes.

After the war Taylor returned to Trinity and worked on an application of turbulent flow to oceanography. He also worked on the problem of bodies passing through a rotating fluid. In 1923 he was appointed to a Royal Society research professorship as a Yarrow Research Professor. This enabled him to stop teaching, which he had been doing for the previous four years, and which he both disliked and had no great aptitude for. It was in this period that he did his most wide-ranging work on fluid mechanics and solid mechanics, including research on the deformation of crystalline materials which followed from his war work at Farnborough. He also produced another major contribution to turbulent flow, where he introduced a new approach through a statistical study of velocity fluctuations.

In 1934, Taylor, roughly contemporarily with Michael Polanyi and Egon Orowan, realised that the plastic deformation of ductile materials could be explained in terms of the theory of dislocations developed by Vito Volterra in 1905. The insight was critical in developing the modern science of solid mechanics.

In 1936 he presented the Royal Institution Christmas Lectures, on "Ships". One of these, on "why ships roll in a rough sea", was the first RI Christmas Lecture to be televised, by the BBC.

Manhattan Project
During World War II, Taylor again applied his expertise to military problems such as the propagation of blast waves, studying both waves in air and underwater explosions.

Taylor was sent to the United States in 1944-1945 as part of the British delegation to the Manhattan Project. At Los Alamos, Taylor helped solve implosion instability problems in the development of atomic weapons, particularly the plutonium bomb used at Nagasaki on 9 August 1945.

In 1944 he also received his knighthood and the Copley Medal from the Royal Society. He was elected to the United States National Academy of Sciences the following year

Taylor was present at the Trinity nuclear test, July 16, 1945, as part of General Leslie Groves' "VIP List" of just 10 people who observed the test from Compania Hill, about 20 miles (32 km) northwest of the shot tower. By coincidence, Joan Hinton, another direct descendant of the mathematician George Boole, had been working on the same project and witnessed the event in an unofficial capacity. They met at the time but later followed different paths. Joan, strongly opposed to nuclear weapons, defected to Mao's China, while Taylor maintained that political policy was not within the remit of the scientist.

In 1950, he published two papers estimating the yield of the explosion using the Buckingham Pi theorem, and high speed photography stills from that test, bearing timestamps and physical scale of the blast radius, which had been published in Life magazine. He gave two estimates of 16.8 and 23.7 kt, close to the accepted value of 20 kt, which was still highly classified at that time.

Later life
Taylor continued his research after the war, serving on the Aeronautical Research Committee and working on the development of supersonic aircraft. Though he officially retired in 1952, he continued research for the next twenty years, concentrating on problems that could be attacked using simple equipment. This led to such advances as a method for measuring the second coefficient of viscosity. Taylor devised an incompressible liquid with separated gas bubbles suspended in it. The dissipation of the gas in the liquid during expansion was a consequence of the shear viscosity of the liquid. Thus the bulk viscosity could easily be calculated. His other late work included the longitudinal dispersion in flow in tubes, movement through porous surfaces, and the dynamics of thin sheets of liquids.

Between the ages of 78 and 83, Taylor wrote six papers on electrohydrodynamics. In this work he returned to his interest in electrical activity in thunderstorms, as jets of conducting liquid motivated by electrical fields. The cone from which such jets are observed is called the Taylor cone, after him. He went on to publish two more papers, on additional topics, in 1971 and 1973. In 1972 D. H. MIchael read Taylor's paper, on making holes in a thin sheet of liquid, at the 13th International Conferences for Theoretical and Applied Mechanics in Moscow. Taylor had suffered a stroke and could not attend. He had presented at every one of the previous conferences.

Aspects of Taylor's life often found expression in his work. His over-riding interest in the movement of air and water, and by extension his studies of the movement of unicellular marine creatures and of weather, were related to his lifelong love of sailing. In the 1930s he invented the 'CQR' anchor, which was both stronger and more manageable than any in use, and which was used for all sorts of small craft including seaplanes.