1. High Performance Computing:

The main contribution from Prof. Tapan K Sengupta and HPCL, IIT Kanpur has been in the area of solving the Turbulence problem by HPC starting from first principles. The relevant references are as given in:

(a) Spatiotemporal growing wave-fronts in spatially stable boundary layers - with Kameswara Rao, A. & Venkatasubbaiah K.; Physical Review Letters vol. 96, pp 224504-1 to 4 (2006)
(b) Onset of turbulence from the receptivity stage of fluid flows - with S. Bhaumik Physical Review Letters, vol. 107, 154501 (2011)
(c) Direct numerical simulation of two-dimensional wall-bounded turbulent flows from receptivity stage - with S. Bhaumik and Y. Bhumkar, Phys. Rev. E, vol. 85(2), pp 026308, (2012)
(d) Precursor of transition to turbulence: Spatiotemporal wave front - with Swagata Bhaumik, Phys. Rev. E, 89, 043018 (2014)

Other major contributions are as follows:

(i) Global Spectral Analysis for Discrete Computing and q- waves.

Ref.: (a) Analysis of central and upwind compact schemes - with Ganerwal G., and De S.; J. Comp. Phys. vol. 192(2), pp 677-694 (2003)
(b) Spurious waves in discrete computation of wave phenomena and flow problems - with Y. Bhumkar, M. K. Rajpoot, V. K. Suman and Shakti Saurabh, Applied Math. Computation, vol. 218, pp 9035-9065 (2012)

(ii) Design of Compact Schemes in Transformed Plane Computations.

Ref.: (a) High accuracy compact schemes and Gibbs' phenomenon - with Ganeriwal, G. and Dipankar, A.; J. Scientific Comput. vol. 21(3), pp 253-268 (2004)
(b) Navier - Stokes solution by new compact scheme for incompressible flows – with Guntaka, A. and Dey, S.; J. Scientific Comput. vol. 21(3), pp 269-282 (2004)
(c) A new flux - vector splitting compact finite volume scheme – with Jain, R. & Dipankar, A.; J. Computational Physics, vol. 207, pp. 261-281 (2005)
(d) High accuracy schemes for DNS and acoustics – with Sircar, S.K. & Dipankar, A.; Jour. Scientific Comput. vol. 26(2), pp 151-193 (2006)
(e) Symmetrized compact scheme for receptivity study of 2D transitional channel flow - with Dipankar, A.; J. Comp. Physics vol. 215(1), pp 245-273 (2006)
(f) A new velocity–vorticity formulation for direct numerical simulation of 3D transitional and turbulent flows - with S. Bhaumik; J. Comp. Physics, vol. 284, pp 230-260 (2015)
(g) An explicit higher order difference scheme on a compact stencil for elliptic equations on curvilinear geometries - with Kartikey Asthana, Applied Mathematics and Computation, vol. 242, 143-158 (2014)

(iii) Replacing von Neumann's Theory of Error Dynamics for Linear & Nonlinear Equations.

Ref.: (a) Error dynamics: Beyond von neumann analysis - with A. Dipankar, P. Sagaut, J. Comp. Physics vol. 226, pp 1211-1218 (2007)
(b) Error dynamics of diffusion equation: Effects of numerical diffusion and dispersive diffusion- with A. Bhole, J. Comp. Physics, vol. 266, pp 240-251, (2014)
(c) KdV equation and computations of solitons: Nonlinear error dynamics -with V.M. Ashwin, K. Saurabh, M. Sriramkrishnan, P.M. Bagade, MK Parvathi, J. Scientific Comput., vol. 62, No. 3, pp 693-717 (2015)

(iv) Dispersion Relation Preserving (DRP) Schemes: Analysis & Design.

Ref.: (a) A comparative study of time advancement methods for solving Navier-Stokes equations – with Dipankar, A.; J. Scientific Comput. vol. 21(2), pp 225-250 (2004)
(b) Optimal time advancing dispersion relation preserving schemes - with M. K. Rajpoot, Pravir K. Dutt, J. Comput. Physics, vol. 229, pp 3623- 3651 (2010)
(c) Space-time discretizing optimal DRP schemes for flow and wave propagation Problems- with M. K. Rajpoot and Y. G. Bhumkar, Comput. Fluids, vol. 47(1), pp 144-154 (2011)

(v) Combined Compact Difference Schemes: Finding of Polygonal Core Vortex in a Shear Driven Flow.

Ref.: (a) A new combined stable and dispersion relation preserving compact scheme for non-periodic problems - with V. Lakshmanan and V.V.S.N. Vijay, J. Comput. Physics, vol. 228, pp 3048- 3071 (2009)
(b) Further improvement and analysis of CCD scheme: Dissipation dicretization and de-aliasing properties -with V.V.S.N. Vijay and Swagata Bhaumik. J. Comput. Physics, vol. 228 (17), pp 6150- 6168 (2009)

(vi) Analysis and Design of Padé Filters: Multi-Dimensional & Adaptive filters.

Ref.: (a) New explicit two-dimensional higher order filters- with Yogesh G. Bhumkar, Comput. Fluids, vol. 39, pp 1848-1863 (2010)
(b) Adaptive multi-dimensional filters, Y. G. Bhumkar and T. K. Sengupta, Comput. Fluids, vol. 49, pp 128-140 (2011)

(vii) Parallel Compact Schemes: Analysis and Design.

Ref.: (a) A new compact scheme for parallel computing using domain decomposition - with A. Dipankar and A. Kameswara Rao. J. Comp. Physics, vol. 220, pp 654-677 (2007)

(viii) Compact Schemes on Non-Uniform Grids.

Ref.: (a) A new alternating Bi-diagonal compact scheme for non-uniform grids - with Aditi Sengupta, J. Comp. Physics, vol. 310, pp 1-25 (2016)

(ix) Implicit Large Eddy Simulation (ILES) - A New Paradigm.

Ref.: (a) Upwind schemes and large eddy simulation - Sengupta T.K., and Nair M.T.; Int. J. Num. Meth. Fluids vol. 31, pp 879-889 (1999)
(b) Design and analysis of a new filter for LES and DES - with Y. Bhumkar and V. Lakshmanan Computers and Structures, vol. 87 (11-12), pp 735-750 (2009)

(x) Direct Numerical Simulation using DRP Schemes.

Ref.: (a) Vortex - induced instability of incompressible wall - bounded shear layer - with De, S., and Sarkar, S.; J. Fluid Mech. vol. 493, pp 277-286 (2003)
(b) Subcritical instability on the attachment - line of an infinite - swept wing – with Dipankar, A.; J. Fluid Mechanics, vol. 529, pp 147-171 (2005)
(c) Onset of turbulence from the receptivity stage of fluid flows - with S. Bhaumik Physical Review Letters, vol. 107, 154501 (2011)
(d) Direct numerical simulation of two-dimensional wall-bounded turbulent flows from receptivity stage - with S. Bhaumik and Y. Bhumkar, Phys. Rev. E, vol. 85(2), pp 026308, (2012)
(e) Direct numerical simulation of transition over a natural laminar flow aerofoil - with Yogesh G. Bhumkar, Frontiers in Aerospace Engineering, vol. 2(1), pp 39-52 (2013)
(f) Direct numerical simulation of 2D transonic flows around airfoils - with Ashish Bhole and N. A. Sreejith, Computers and Fluids, vol. 88, pp 19-37 (2013)
(g) Direct numerical simulation of transitional mixed convection flows: Viscous and inviscid instability mechanisms - with Swagata Bhaumik and Rikhi Bose, Physics of Fluids, vol. 25, 094102 (2013)
(h) Precursor of transition to turbulence: Spatiotemporal wave front - with Swagata Bhaumik, Phys. Rev. E, 89, 043018 (2014)

(xi) Reduced Order Model (ROM): Stuart-Landau-Ekhaus Equation Based Approach.

Ref.: (a) Enstrophy-based proper orthogonal decomposition for reduced-order modeling of flow a past cylinder - T. K. Sengupta, S. I. Haider, Parvathi M. K. and Pallavi G., Physical Review E, vol. 91(4), 043303 (2015)
(b) Enstrophy-based proper orthogonal decomposition of flow past rotating cylinder at super-critical rotating rate - Tapan K. Sengupta and Atchyut Gulapalli, Physics of Fluids, 28 (11), 114107 (2016)

2. Theoretical Fluid Mechanics:

(i) Linear Receptivity Theory for Signal Problem.

Ref.: (a) Impulse response of laminar boundary layer and receptivity – Sengupta T.K. 7th Int. Conf. on Numerical Methods In Laminar and Turbulent Flows. Pineridge Press (1991)
(b) The generation of disturbances in a boundary layer by wall perturbations: The vibrating ribbon revisited once more.- with M. Gaster. In "Instabilities and Turbulence in Engineering Flows".(Eds. D.E. Ashpis, T.B. Gatski and Hirsh R.) Kluwer Academic Publisher. 1993.

(ii) Linear Receptivity Theory of Spatio-Temporal Dynamics.

Ref.: (a) Generation of Tollmien- Schlichting waves by harmonic excitation- with M. Ballav and S. Nijhawan.; Physics of Fluids A, vol. 6, no.3, pp 1213-1222 (1994)
(b) Spatio-temporal growth of disturbances in a boundary layer and energy based receptivity analysis -with Kameswara Rao, A. & Venkatasubbaiah, K.; Phys. of Fluids, vol. 18, pp 094101-1 to 9 (2006)
(c) Spatiotemporal growing wave-fronts in spatially stable boundary layers - with Kameswara Rao, A. & Venkatasubbaiah K.; Physical Review Letters vol. 96, pp 224504-1 to 4 (2006)

(iii) Robins-Magnus Effect & Violation of Prandtl's Limit.

Ref.: (a) Magnus Effect at high speed ratio- with Nair M.T.; In Proc. of 3rd Asian CFD Conf. held at Bangalore, during 7-11 Dec. (1998).
(b) Lift generation and limiting mechanism via unsteady flow development for Magnus- Robins effect – with Gupta, K. & Nair M. T.; Proc. 8th ACFM, China (1999)
(c) Temporal flow instability for Robins - Magnus effect at high rotation rates– with Kasliwal, A., De, S. and Nair. M.; J. Fluids & Structures vol. 17, pp 941-953 (2003)
(d) Robins - Magnus effect: A continuing saga -with Srikanth B. Talla, Current Science. Vol. 86, no. 7 pp 1033-1036 (2004)

(iv) Upstream Propagating Waves and Free Stream Excitation.

Ref.: (a) A new class of waves for blasius boundary layer – with Nair M.T.; In Proc. of 7th Asian Congress of Fluid Mechanics (ACFM). Held at IIT. Madras (1997)

(v) Vortex Induced Instability and Bypass Transition.

Ref. (a) By-pass mechanism of transition to turbulence- with Chattopadhyay, M., Wang, Z.Y. and Yeo, K.S.; J. Fluids & Structures. vol. 16(1), pp 15-29 (2002)

(vi) Mechanical Energy Based Nonlinear/ Linear Instability Theory.

Ref. : (a) Vortex - induced instability of incompressible wall - bounded shear layer - with De, S., and Sarkar, S.; J. Fluid Mech. vol. 493, pp 277-286 (2003)
(b) Spatio-temporal growth of disturbances in a boundary layer and energy based receptivity analysis -with Kameswara Rao, A. & Venkatasubbaiah, K.; Phys. of Fluids, vol. 18, pp 094101-1 to 9 (2006)

(vii) Proposing Bromwich Contour Integral Method: Spatio-Temporal Wave Front from Orr-Sommerfeld Equation and Validation from Solution of Navier-Stokes Equation.

Ref.: (a) Generation of Tollmien- Schlichting waves by harmonic excitation- with M. Ballav and S. Nijhawan.; Physics of Fluids A, vol. 6, no.3, pp 1213-1222 (1994)
(b) Spatiotemporal growing wave-fronts in spatially stable boundary layers - with Kameswara Rao, A. & Venkatasubbaiah K.; Physical Review Letters vol. 96, pp 224504-1 to 4 (2006)
(c) Onset of turbulence from the receptivity stage of fluid flows - with S. Bhaumik Physical Review Letters, vol. 107, 154501 (2011)

(viii) Nonlinear Theory of Flow Instability Based on Proper Orthogonal Decomposition (POD).

Ref.: (a) Nonlinear receptivity and instability studies by POD – with S. Bhaumik & Y. G. Bhumkar. 6th AIAA Theoretical Fluid Mechanics Conf., Honululu, Hawaii, USA, 27-30 June 2011.

(ix) Enstrophy Transport Equation for Inhomogeneous Flows: Beyond Kolmogorov's Theory.

Ref.: (a) Diffusion in inhomogeneous flows: Unique equilibrium state in an internal flow- with H. Singh, S. Bhaumik and R. Roy Chowdhury, Computers and Fluids, vol. 88, pp 440-451 (2013)

(x) Dynamical System Theory and Multiple Hopf Bifurcations for Vortex Dominated Flows.

Ref.: (a) Dynamical system approach to instability of flow past a circular cylinder - Tapan K. Sengupta, Neelu Singh and V. K. Suman, J. Fluid Mechanics, vol. 656, pp 82-115 (2010)
(b) Universal instability modes in internal and external flows, Tapan K. Sengupta, V. V. S. N. Vijay and Neelu Singh, Comput. Fluids, vol. 40(1), pp 221-235 (2011)

(xi) Introducing Bulk Viscosity & Replacing Stokes Hypothesis: HPC with Non-Equilibrium Thermodynamics for Rayleigh-Taylor Instability.

Ref.: (a) Non-equilibrium thermodynamics of Rayleigh-Taylor instability- with A. Sengupta, S. Sengupta, A. Bhole and KS Shruti, Int. J. Thermophysics, vol. 37(4), pp 1-25 (2016)
(b) Roles of bulk viscosity on Rayleigh-Taylor instability: Non-equilibrium thermodynamics due to spatio-temporal pressure fronts- with Aditi Sengupta, Nidhi Sharma, Soumyo Sengupta, Ashish Bhole, and K S Shruti, Physics of Fluids, vol. 28, 094102 (2016)
(c) Non-equilibrium thermodynamics of Rayleigh-Taylor instability, Tapan K. Sengupta, Aditi Sengupta, KS Shruti, Ashish Bhole. Journal of Physics Conference Series 759(1):012079 (2016)

3. Contribution to Teaching and dissemination of HPC

Have been teaching high performance computing during the last twenty five years in IIT Kanpur, NUS Singapore and have provided special courses in different forum including IISc Bangalore, HAL Management Academy Bangalore. The major activities are:

1. Writing the following two text books on Scientific Computing, HPC and applications:

(a) "Fundamentals of CFD : Tapan K Sengupta" (2004) published by Universities Press, Hyderabad, India.
(b) "High Accuracy Computing Methods: Fluid Fows and Wave Phenomena" (Cambridge Univ. Press, USA, July, 2013) by Tapan K. Sengupta.
(c) "Theoretical and Computational Aerodynamics" (John Wiley, UK, 2015) by Tapan K. Sengupta, John Wiley & Sons, Aerospace Series Text Book

2. A course has been conducted under the auspices of NPTEL for global audience on HPC and available at:

a. Foundations of Scientific Computing (2009)

http://nptel.ac.in/courses/101104013/

3. A lecture series titled : High Accuracy Computing T.K. for one week at Dept. of Mathematics, IISc Bangalore under the auspices of IISc Mathematics Initiative (IMI) in April, 2005.

4. A summer school for one week was organized at Central Institute of Mechanical Sciences (CISM) at Udine (Italy) in June 2008 on: Instabilities of Flows: with and without Heat Transfer and Chemical Reaction with the CISM monograph co-authored with Prof. Thierry Poinsot (CNRS/ IMFT, Toulouse, France) is published by Springer-Wien New York (2010)

5. Organizing chairman of IUTAM symposium on Advances in Computation, Modeling and Control of Transitional and Turbulent Flows in Dec. 2014, an event specifically held on HPC. Symposium Proceedings: "Advances in Computation, Modeling and Control of Transitional and Turbulent Flows." (Editors: Profs. T. K. Sengupta, S. K. Lele (Stanford Univ., USA), K. R. Sreenivasan (New York Univ., USA) and P. A. Davidson (Univ. of Cambridge, UK)) World Scientific Publishing Company, Singapore (2015)

6. CISM course to be held on High Performance Computing and Reduced Order Modeling for Fluid Turbulence, organized by Prof. T. K. Sengupta and Prof. Sergio Pirozzoli, Univ. of Rome. Other teaching faculty members are: Prof. G. Iaccirino (Stanford Univ., USA), Prof. Paul Tucker (Univ. of Cambridge, UK), Prof. Mejdi Azaiez (Univ. of Bordeaux, France), Prof. Thierry Poinsot (CERFACS, France). Dates: 21st to 25th May, 2018 (36 lectures).

Tapan K. Sengupta , Ph.D. ( Georgia Tech.) has been involved in research and teaching scientific computing for fluid flow and wave phenomenon for more than two decades in India and abroad. His interest is in developing numerical techniques for high accuracy computing and HPC of transitional and turbulent flows, and high resolution schemes for compressible flows and problems of atmospheric sciences. Theoretical fluid mechanics continues to be the area of primary interest.

• Awards, Fellowships and other Recognitions of Prof. T. K. Sengupta

1) Senior Visiting Fellow: Dept. of Mechanical Engineering, National Univ. of Singapore, Singapore. During 1999-2001 and July - December 2003.
2) Senior Associate: 2005 to 2011 at of International Centre of Theoretical Physics (ICTP) at Trieste, Italy.
3) Regional Editor, Computers & Fluids (Elsevier), New York, USA (2010-2014)
4) Associate Editor: Int. J. Emerging Multidisciplinary Fluid Sciences (Multi-Science Publishing, U.K.)
5) P. R. Dwivedi Chair Professor of Aerospace Engineering, IIT Kanpur (2011-2014).
6) Certificate of outstanding contribution in reviewing: Journal of computational physics, awarded July, 2015 to Prof. Tapan K. Sengupta.
7) Visiting IdeX Professor of Excellence, 12M Laboratory of the Univ. of Bordeaux, France, Dec., 2015 to Oct. 2016
8) Visiting Fellow, Univ. of Cambridge, UK at Murray-Edwards College and Univ. Engg., Dept. July, 2016 to Oct 2016.

• Contributions to the Institute

1. P. R. Dwivedi Chair Professor of Aerospace Engineering, IIT Kanpur (2011-2014).
2. High Performance Computing Laboratory (HPCL) in Department of Aerospace Engineering, IIT Kanpur, India

• Contributions Outside the Institute

1) Senior Associate: 2005 to 2011 at of International Centre of Theoretical Physics (ICTP) at Trieste, Italy.
2) Senior Visiting Fellow, National Univ. of Singapore, 1999 -2001.
3) Visiting Fellow, Technical Univ. Munich, Germany May-June, 2001.
4) Visiting Professor, Ecole Polytechnique, Montreal, Canada June-July, 2012.
5) Visiting Professor, McGill University, Montreal, Canada May – July, 2013.
6) Visiting Professor of excellence for IdeX programme of Univ. of Bordeaux, France; Dec. 2015 – Oct. 2016.
7) Visiting Fellow, Univ. of Cambridge, UK at Murray-Edwards College and Univ. Engg., Dept. July, 2016 to Oct 2016.
8) Co-Chair of ICOMEC12, Int. Conf. on Meta-Computing,Bhubaneshwar, India (Dec., 2012).
9) Organizing Chairman of IUTAM Symposium on “Advances in Numerical Methods, Modeling and Control of Transitional and Turbulent Flows” in Goa, India, December, 2014.
10) Organizing Session in 3rd MIT Conf. Solid and Fluid Mechanics, MIT USA, 2003.
11) Organizing Session in Boundary and Interior Layers (BAIL-2006) Conf. held in Goettingen, Germany, 2006.
12) Organizing Chairman of Summer School at International Centre of Mechanical Sciences (CISM) Udine, Italy on Transition and Turbulence, June 2008
13) Expert lectures on computational acoustics (with Prof. D. V. Gaitonde, OSU (USA), Drs. Y. G. Bhumkar and A. Satyanarayana, IIT Bhubaneswar) at IIT Bhubaneswar, under GIAN programme of MHRD during June, 2016.

• Development of Technologies, Projects and Technology Transfer etc.

a) DMRC Railway project on Tunnel Aerodynamics and Sonic Boom (2007)
b) NLF wing for regional transport aircraft development for NAL (2007 -2009)
c) Antennae integration for coast guard and defense services for HAL Kanpur (2008 – 2014)
d) Analysis of pusher propeller aircraft design for NAL Bangalore (2009-2010)
e) Design and development of deployable flight data recorder unit (DFDRU) for HAL Korwa (2010-2014)
f) Aerodynamics of micro air vehicles (MAVs) for DRDO-NPMICAV project (2010 -2014)