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Announcements related to HPCL

Transition to turbulence-- the physical mechanism explained in:
Precursor of Transition to Turbulence: spatiotemporal wave front
by: Swagata Bhaumik and Tapan K Sengupta; In: Physical Review E.
PREVIEW LINK: http://spectral.iitk.ac.in/hpcl/LH13761E_25April2014.pdf
Journal link: http://journals.aps.org/pre/accepted/b307fY87Ub91fc3bd7776bb1d6fd45e9cb1...
Newer Developments to be announced in the IUTAM symposium listed just below
Invitation to attend the symposium: Please contact Prof. Tapan K Sengupta at tksen@iitk.ac.in
Please see details at SYMPOSIUM WEBSITE URL: http://spectral.iitk.ac.in/hpcl/IUTAM2014

IUTAM Symposium:
Advances in Computation, Modeling and Control of Transitional and Turbulent Flows
DATES: 15-18 December, 2014; VENUE: Hotel MARRIOTT, Goa.
HOST INSTITUTE: IIT Kanpur (with support of Stanford University, USA)
CONFERENCE CHAIRS: Profs. S K Lele (Stanford U.) & T K Sengupta (IIT Kanpur)
SYMPOSIUM WEBSITE URL: http://spectral.iitk.ac.in/hpcl/IUTAM2014

Third International Conference on Meta Computing 2012, held in Bhubaneswar. Conference Co-Chair: Prof. Tapan K Sengupta
Best papers: Drs. V. Mudkavi/ K. Venkatesh (NAL Bangalore) and Pramod Bagade/ B. Satish (IIT Kanpur)


DNS of Transition and Turbulence in Physical Review Letters - see link (1) below.
Also the paper: "Direct numerical simulation of two-dimensional wall-bounded turbulent flows
from receptivity stage" February 2012, Physical Review E (Vol.85, No.2):
URL: http://link.aps.org/doi/10.1103/PhysRevE.85.026308
Related links :
(1) http://prl.aps.org/abstract/PRL/v107/i15/e154501
(2) http://prl.aps.org/abstract/PRL/v96/i22/e224504
(3) http://www.sciencedirect.com/science/article/pii/S0021999107002537

The IIT Kanpur, HPCL group has provided definitive answers to CAUSALITY of turbulence
in wall bounded boundary layers. Through the work on Bromwich contour integral method
(developed in IITK since 1990) spatio-temporal wave-front (STWF) have been shown as the main
precursor to transition and turbulence (PRL, 2006, 2011, PRE 2014 and the CRC text book, see the side-bar).
High accuracy computing of Navier-Stokes equation also attest to formation of STWF leading to fully-developed
turbulence via deterministic excitation of laminar flow in RECEPTIVITY framework.

News

    IUTAM symposium on Advances in Computation, Modeling and Control of Transitional and Turbulent Flows will be held in Hotel Marriott Goa, India during 15-18 December, 2014. Visit the web-site: http://spectral.iitk.ac.in/hpcl/IUTAM2014

    Paper titled Precursor of transition to turbulence: Spatio-temporal wave front by Dr. Swagata Bhaumik and Tapan Sengupta has appeared in Phys. Rev. E. Click here for paper

    Article Usage for: "Direct Numerical Simulation of 2D Transonic Flows around Airfoils," Sengupta T.K., Bhole A., Sreejith N.A., Click here

    HPCL news: " KdV equation and computation of Solitons: Nonlinear error dynamics," Ashwin Vishnu M, Kumar Saurabh, M Sriramkrishnan, PM Bagade, MK Parvathi and Sengupta T.K., This is an outcome of a term paper by the listed students in Advanced Scientific Computing course (AE605).

    Article Usage for: "Diffusion in inhomogeneous flows: Unique equilibrium state in an internal flow," Tapan K. Sengupta, Himanshu Singh, Swagata Bhaumik, Rajarshi Roy Chowdhury, Click here

    The book : "Theoretical and Computational Aerodynamics" has been published by Wiley, UK. This contains chapters on (i) computational aerodynamics, (ii) NLF and transitional flow related to aerodynamics, (iii) transonic aerodynamics and (iv) low Reynolds number unsteady aerodynamics.

    The book: "High Accuracy Computing Methods: Fluid Flows and Wave Phenomena" is published by Cambridge University Press (2013) with an Indian edition available. This supersedes the book from Universities Press, India (2004). Foreword written by Prof. Michel Deville. See:
http://www.cambridge.org/9781107023635

    Swagata Bhaumik defended his Ph.D. thesis on 2D and 3D flow receptivity and transition. He is currently now in OSU working with Prof. D. V. Gaitonde. His work on transition and turbulence is culmination of contributions by HPCL over the past two decades, starting with the work on Bromwich contour integral methods.

    Our work on rectangular lid driven cavity is published in Computers and Fluids, highlighting the enstrophy cascade mechanism for inhomogeneous flow and is a significant improvement over existing ideas on energy cascade based on homogeneous isotropic turbulence. This unlike Kolmogorov's theory is equally true for 2D and 3D flows for the cascade of scales.

    A 40 parts lecture series on Foundations of Scientific Computing taught to IIT Kanpur undergraduate students (2009) as a science elective is available in you tube and in:
http://nptel.iitm.ac.in/courses/101104013/1

    TKS visited in 2012: (i) Ecole Polytechnique, Montreal (June-July, 2012); (ii) Center for Advanced Studies in Theoretical Sciences (CASTS) and Taida Institute of Mathematical Sciences (TIMS) at National Taiwan Univ., Taipei, Taiwan for Progress in Mathematical and Computational Studies on Science and Engineering Problems conference, 5 - 7 November, 2012. Photo

    Dr. Yogesh Bhumkar left HPCL on 6th August 2012, after his Ph.D. on bypass transition (2006-2012). After a short stint at NTU, Taipei, he is currently a faculty member in IIT Bhubhaneswar.

    The book: "Instabilities of Flows and Transition to Turbulence" published by CRC Press, Taylor & Francis Group, USA is available. Details of the book are in:
http://www.crcpress.com/product/isbn/9781439879443

    Prof. T. K. Sengupta has helped Tata McGraw-Hill for the Indian edition of Fundamentals of Aerodynamics by Prof. J. D. Anderson, augmented with SI Metrication and a chapter on Aerodynamic Research Activities in India written by him.

    Prof. Michel Deville's visit to HPCL in 2010: Prof. Michel Deville ( Ecole Polytechnique Federale de Lausanne, Switzerland) visited HPCL and delivered lectures on Spectral Element Method . Photo

    Recent trends in HPC at HPCL, IIT Kanpur, Sep 2009: Account of work done in HPCL, IIT Kanpur, on methods for DNS/ LES was displayed in the Workshop on "High Performance Computing in India" in conjunction with "Supercomputing 2009" (SC09), Nov. 14-20, 2009 (USA).

    Issues related to DNS / LES were the central themes of the plenary talk given at the Fifth M.I.T. conference at Boston, June 2009

1. Three-time level methods like second order Adam-Bashforth schemes are incorrectly used for "DNS". Following papers show that numerical/ spurious modes remove large fraction of initial condition at higher frequencies. Details in HIGH ACCURACY COMPUTING METHOD (CUP, 2013) and the following papers:

a) A Comparative Study of Time Advancement Methods for Solving Navier-Stokes Equations

Dowload comparative study.. paper from springerlink

b) High Accuracy Schemes for DNS and Acoustics

Download the DNS and acoustics paper from springerlink

2. The von Neumann analysis for PDEs has been corrected, with the help of 1D convection equation. See the CUP book and the following from J. Computational Physics:

a) Error Dynamics: Beyond von Neumann Analysis -- T.K. Sengupta, A. Dipankar and P. Sagaut, 226, 1211-1218 (2007)
Dowload Error dynamics: Beyond von Neumann analysis paper from Science Direct