IISc Bangalore

Sourabh Suhas Diwan

Associate Professor

Email: sdiwan[at]iisc.ac.in
Office Phone Number: +91-80-22932423
Lab Phone Number: +91-80-22933045
Office Room Number: AE213



B.E. (Mechanical Engg.): Walchand College of Engineering Sangli, 2002.
MSc Engg. (Aerospace Engg.): Indian Institute of Science Bangalore, 2005.
PhD (Aerospace Engg.): Indian Institute of Science Bangalore, 2009.


Postdoctoral Research Associate, Jawaharlal Nehru Centre for Advanced Scientific Research Bangalore, (2009-2012).
Postdoctoral Research Associate, Imperial College London, (2012-2016).

Research Interests

  • Experimental aerodynamics
  • Bypass transition in boundary layers
  • Turbulent flows
  • Hydrodynamic stability
  • Atmospheric flows


Post-doctoral Research Fellow:

Date: 21/11/2020

Opening for a post-doc position to work on DNS of COVID-19 related flows

Applications are invited for the position of a post-doctoral research fellow, to work on a project entitled “Direct numerical simulation of cough/sneeze/speech flows for understanding transmission dynamics of COVID-19-type infections”. This is a multi-institutional project involving researchers from IISc-Bengaluru, ICTS-TIFR-Bengaluru, JNCASR-Bengaluru and Nordita (KTH)- Stockholm. For more details, see https://link.springer.com/article/10.1007/s41403-020-00106-w

The project involves

  • To carry out direct numerical simulations (DNS) for cough/sneeze/speech flows using an available code, on a supercomputer housed at one of these institutes.
  • To modify the existing code to include the dynamics of individual liquid droplets, including gravitational settling and phase change, and to parallelize the modified code.
  • To carry out a study on the computed results to improve our understanding of these flows, and to develop physics-based models.

Required qualifications/skills are as follows:

  • PhD in Mechanical/Aerospace/Chemical Engineering or in Physics with the PhD topic being in computational and theoretical fluid dynamics.
  • Strong understanding of fluid dynamics, turbulence and moist thermodynamics.
  • Good expertise in numerical programming, code parallelization and running codes on a supercomputer.
  • Strong publication record.
  • Excellent writing and communication skills.

The Postdoctoral Fellow will be expected to make independent and rapid progress.

Those interested are encouraged to apply to the Raman Post-doc program at IISc (https://iisc.ac.in/post-docs/) or the ICTS post-doctoral fellowship program (https://www.icts.res.in/academic/postdoctoral-fellowships). These fellowships are highly competitive and only outstanding candidates will be considered.

For informal queries on the position and the project, contact Dr. Sourabh S. Diwan (sdiwan@iisc.ac.in) / Prof Rama Govindarajan (rama@icts.res.in).

Research Statement

This will be updated soon.



Current Projects

  • ARDB project on “Development of probes for highly-resolved measurement of pressure fluctuations in transitional and turbulent flows”. (Jan 2019 – Jan 2021).
  • SERB Early Career Research Award for the project entitled “Manipulation of wall turbulence by external forcing for investigating mechanisms causing surface friction drag on transport vehicles”. (March 2019- March 2022).
  • ISRO-IISc Space Technology Cell project on “Wall pressure spectrum beneath a turbulent boundary layer: measurement and semi-empirical modelling”. (April 2019 – March 2021).
  • DST project as part of the National Centre for Clean-coal Research and Development at the ICER, IISc, Bangalore (PI: Prof Pradeep Datta, Department of Mechanical Engineering, IISc). Co-investigator in Work Package 2 “Heat Exchange Relevant to Supercritical Fluid Power Plants”  (November 2018 – November 2023).
  1. Diwan SS, Morrison JF. Spectral structure and linear mechanisms in a rapidly distorted boundary layer. Int. J. Heat Fluid Flow. 67. 63-73. 2017
  2. Morrison JF, Diwan SS. Inner-outer interaction in a rapidly sheared boundary layer. In 10th International Symposium on Turbulence and Shear Flow Phenomena (TSFP10). Chicago, USA. 2017
  3. Diwan SS. “Necessary conditions for spatial inviscid instability”. Proceedings of Royal Society London A. 2015;471. 2015
  4. Diwan SS, Prasanth P, Sreenivas KR, Deshpande SM, Narasimha R. “Cumulus-type flows in the laboratory and on the computer: simulating cloud form, evolution and large-scale structure”. Bulletin of American Meteorological Society. 2014;95. 2014
  5. Diwan SS, Morrison JF. Pressure measurements in a rapidly sheared turbulent wall layer. In American Physical Society-Division of Fluid Dynamics 67th Annual Meeting. San Francisco, California, USA. 23-25. 2014
  6. Diwan SS, Ramesh ON. Relevance of local parallel theory to the linear stability of laminar separation bubbles. Journal of Fluid Mechanics. 2012;698. 2012
  7. Rao VG, Diwan SS, Sreenivas KR, Narasimha R, Venkatakrishnan L, Suriyanarayanan P. Laboratory simulation of the life-cycle of a cumulus congestus cloud. In Opportunities and Challenges in Monsoon Prediction in a Changing Climate. Pune, India. 2012
  8. Narasimha R, Diwan SS, Duvvuri S, Sreenivas KR, Bhat GS. Laboratory simulations show diabatic heating drives cumulus-cloud evolution and entrainment. Proceedings of National Academy of Sciences of the USA. 2011;108. 2011
  9. Diwan SS, Narasimha R, Bhat GS, Sreenivas KR. Laboratory studies of anomalous entrainment in cumulus cloud flows. Journal of Physics: Conference Series.. 2011. 2011
  10. Narasimha R, Diwan SS, Subrahamanyam D, Sreenivas KR, Bhat GS. Entrainment in Laboratory Simulations of Cumulus Cloud Flows. In American Geophysical Union, Fall Meeting. 2010
  11. Diwan SS, Ramesh ON. On the origin of the inflectional instability of a laminar separation bubble. Journal of Fluid Mechanics. 2009;629. 2009
  12. Diwan SS, Ramesh ON. Laminar separation bubbles: Dynamics and control. Sadhana (Proceedings of Indian Academy of Sciences). 2007;32. 2007
  13. Diwan SS, Ramesh ON. On the Late Stages of Transition in Laminar Separation Bubbles. In 11th Asian Congress of Fluid Mechanics. Kuala Lumpur, Malaysia. 22-25. 2006
  14. Diwan SS, Chetan SJ, Ramesh ON. On the bursting criterion for laminar separation bubbles. In Sixth IUTAM Symposium on Laminar-Turbulent Transition. Bangalore, India. 2004
  15. Diwan SS, Chetan SJ, Ramesh ON. On the Origin of Three-Dimensionality in a Two-Dimensional Laminar Boundary Layer Separation. In American Physical Society-Division of Fluid Dynamics 57th Annual Meeting. Seattle, Washington, USA. 2004
  16. Morrison J, Septham K, Diwan SS, Sanmiguel-Vila C. Effects of shear and blocking in a rapidly distorted boundary layer. In Wall Turbulence: A colloquium under the midnight sun. Throndheim, Norway. 2004
  17. Subramanyam D, Sreenivas KR, Bhat GS, Diwan SS, Narasimha R. “Experimental study of starting plumes simulating cumulus cloud flows in the atmosphere”. In American Physical Society-Division of Fluid Dynamics 62nd Annual Meeting. Minneapolis, Minnesota, USA. 2004

PhD students: 

Abhishek Tyagi

Aditya Anand

Amey Agharkar (jointly with Prof Pramod Kumar, ME)

Robin Joseph

Rohit Singhal

Satyajit DE

Srinivas Kirthy K (jointly with Prof. O. N. Ramesh, AE)



Project Associates:

I. Sai Eswar (ARDB project)

Chandan Kumar A. (SERB project)

B K Suhas (ISRO-STC project)

Post-doc Associates:


Dr Samson Annapu Reddy


Dr P Phani Kumar