G Rajesh

Associate Professor

Department of Aerospace Engineering

IIT Madras

Email : rajesh@ae.iitm.ac.in

Ph No : +91 44 2257 4032

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Research Interests : Experimental Aerodynamics - High Speed Flows & Shockwave Dynamics

If I have seen further, it is by standing on the shoulders of Giants

Isaac Newton

Current Research

Future Plans

Funded Projects

Important publications


14. Shobhan Roy and G Rajesh, 2018, "An Analytical Model for Asymmetric Mach Reflection Configuration in Steady Flows," J. Fluid Mechanics (Accepted for Publication).
13. R Arun Kumar and G Rajesh, 2018, "Physics of Vacuum Generation in Zero-Secondary Flow Ejectors," Physics of Fluids, 30, 066102. (Selected as Editor's Pick.) DOI
12. R Arun Kumar and G Rajesh, 2017, "Shock Transformation and Hysteresis in Underexpanded Confined Jets," J. Fluid Mechanics, 823, 538-561. DOI
11. R Arun Kumar and G Rajesh, 2016, "Flow Transients in Un-started and Started Modes of Vacuum Ejector Operation," Physics of Fluids, 28, 056105. DOI
10. Ankit Mittal, G Rajesh, V. Lijo, and H. D. Kim, 2014, "Starting Transients in a Vacuum Ejector-Diffuser System,” J. Propulsion and Power, 30(6), 1213-1223.DOI
9. C. K. Muthukumaran, G Rajesh, and H. D. Kim, 2013, “Launch Dynamics of Supersonic Projectiles,” J. of Spacecraft and Rockets, 50 (6), 1150-1161.DOI
8. V. Lijo, H. D. Kim, G Rajesh, and T. Setoguchi, 2010, “Numerical Simulation of Transient Flows in a Vacuum Ejector-Diffuser System,” J. Aerospace Engineering, IMechE, 224(7), pp.777-786.
7. G Rajesh, H. D. Kim, and T. Setoguchi, 2008, “The Projectile Aerodynamics Overtaking a Shock Wave,” J. Spacecraft and Rockets, 45(6) pp.1251-1261.
6. G Rajesh, R. Mishra, H. G. Kang, and H. D. Kim, 2007, “Computational Study of the Compressible Flow Driven by a Piston in a Ballistic Range,” J. Thermal Sciences, Springer, 16(4), pp.360-369.
5. G Rajesh, H. D. Kim, T. Setoguchi, and S. Raghunathan, 2007, “Performance Analysis and Enhancement of the Ballistic Range,” J. Aerospace Engineering, IMechE, 221(5), pp.649-659.
4. G Rajesh, H. D. Kim, S. Matsuo, and T. Setoguchi, 2007, “A Study of the Unsteady Projectile Aerodynamics Using a Moving Coordinate Method,” J. Aerospace Engineering, IMechE, 221(5), pp.691-706.
3. Rajesh Gopalapillai, Heuy-Dong Kim, Toshiaki Setoguchi and Shigeru Matsuo, 2007, “On the Near-Field Aerodynamics of a Projectile Launched from a Ballistic Range,” J. Mechanical Science and Technology, 21(7), pp.1129-1138.
2. G Rajesh, J. M. Lee, S.C. Back, and H. D. Kim, 2006, “Theoretical Study for the Design of a New Ballistic Range,” J. Mechanical Science and Technology, 20(7), pp.1019-1029.
1. H. D. Kim, G Rajesh, T. Setoguchi, and S. Matsuo, 2006, “Optimization Study of a Coanda Ejector,” J. Thermal Sciences, Springer, 15(4), pp.331-336.

National and International Conferences


40. Sreelal M R and G Rajesh, 2018, "Performance Analysis of Rapid Separation Sabot on an FSAPDS Projectile ," 7th Asian Joint Workshop on Thermal and Fluid Sciences, November, Thiruvananthapuram, Kerala.
39. Sivaprasad G, Arun Kumar R, G Rajesh and Kim H D, 2018, "A Comparitive Study on the Start-up Process in Single Stage and Two Stage Vacuum Ejectors," 7th Asian Joint Workshop on Thermal and Fluid Sciences, November, Thiruvananthapuram, Kerala..
38. Thara Reshma, Rohit Jejani, and G Rajesh, 2018, "Some Interesting Shockwave Transitions in Weak Shock Reflection Domain," 32nd National Convention of Aerospace Engineers, BIT Mersa, Ranchi, India.
37. Sreelal M R and G Rajesh, 2018, "A Study on Shock Interactions in A Sabot Separation Process," 25th International Symposium on Military Aspects of Blast and Shock, September, The Hague, The Netherlands.
36. Yousaf Saidalavi, G Rajesh and Gabi Ben-Dor, 2018, "A Study of Shock Interactions Inside A Helmet Under Blast Loading," 25th International Symposium on Military Aspects of Blast and Shock, September, The Hague, The Netherlands.
35. Arun Kumar R and G Rajesh, 2018, "Shock Wave Diffraction Over Under Water Bodies," 25th International Symposium on Military Aspects of Blast and Shock, September, The Hague, The Netherlands.
34. Shobhan Roy and G Rajesh, 2018, "An Analytical Model for Asymmetric Mach Reflection Confguration in 2-D Steady Flows," 23rd International Shock Interaction Symposium, July, Kruger National Park, South Africa.
33. Vinoth P, Sushmitha J and G Rajesh, 2018, "Analytical and Numerical Predictions of Mach Stem height in Overexpanded and Underexpanded 2-D Jets," 23rd International Shock Interaction Symposium, July, Kruger National Park, South Africa.
32. Sivaprasad G, Arun Kumar R and G Rajesh, 2018, "Flow Visualization of 3-D shock Transformations in Cylindrical Vacuum Ejectors," 23rd International Shock Interaction Symposium, July, Kruger National Park, South Africa.
31. Arun Kumar R and G Rajesh, 2018, "A Study on the Reflection and Refraction of Blast Wave Sliding Over an Air-Water Interface," 23rd International Shock Interaction Symposium, July, Kruger National Park, South Africa.
30. Vinoth P and G Rajesh, 2018, "Prediction of Mach Stem Height in Overexpanded Jets," 5th National Symposium on Shockwaves," 5th National Symposium on Shockwaves, February 26-28, TBRL Chandigarh. (Best Poster Award)
29. Anilkumar Pasam and G Rajesh, 2018, "A Simpler Criterion for Detachment Condition in Double Wedge Shock Reflections," 5th National Symposium on Shockwaves, February 26-28, TBRL Chandigarh.
28. Arun Kumar R and G Rajesh, 2018, "An Experimental Study on the Blastwave Propagation over an Air-Water Interface," 5th National Symposium on Shockwaves, February 26-28, TBRL Chandigarh.
27. Arun Kumar R and G Rajesh, 2017, "Upstream Pressure Induced MR-RR Shock Transitions," 31st International Symposium on Shockwaves, July 9-14, Nagoya University, Japan.
26. Athira C M and G Rajesh, 2017, "Experimental study on Configuration Effects of Supersonic Projectiles in Transitional Ballistic Regimes," 31st International Symposium on Shockwaves, July 9-14, Nagoya University, Japan.
25. Shobhan Roy and G Rajesh, 2017, "Analytical Prediction of Mach Stem Height for Asymmetric Wedge Reflection in 2-D Steady Flows," 31st International Symposium on Shockwaves, July 9-14, Nagoya University, Japan.
24. K M M Rafi, B A H Fahd, M Deepu, and G Rajesh, 2017, "Experimental and Numerical Studies on Plume Structures of Micro-Nozzles Operating at High Vacuum Conditions," 31st International Symposium on Shockwaves, July 9-14, Nagoya University, Japan.
23. Ijaz Mohamed and G Rajesh, 2017, "Shock interactions in Thrust Optimized Parabolic (TOP) Nozzles during Start-Up and Shut Down," 31st International Symposium on Shockwaves, July 9-14, Nagoya University, Japan.
22. Athira C M and G Rajesh, 2016, "Experimental Study of Projectile -Blast Flow Field Interactions in Transitional Ballistic Regime," 24th International Symposium on Military Aspects of Blast and Shock, September, Halifax, Canada.
21. Badrinarayanan A S and G Rajesh, 2016, "Computational Simulation of Shock Interactions in Supersonic Projectile Launch," 22nd International Shock Interaction Symposium, July, University of Glasgow, United Kingdom.
20. Dheepak N Khatri, Pasam Anil Kumar, G Rajesh, and Santanu Ghosh, 2016, "Hysteresis Phenomenon in reflection of Asymmetric Shock Waves," 22nd International Shock Interaction Symposium, July, University of Glasgow, United Kingdom.
19. Arun Kumar R and G Rajesh, 2016, "Shock Transformations in Vacuum Ejectors," 22nd International Shock Interaction Symposium, July, University of Glasgow, United Kingdom.
18. Arun S, Arun Kumar R, Sameen A, G Rajesh, and Balaji Srinivasan, 2016, "Numerical Investigation of Initial Transients on The Flow Field In A Vacuum Ejector," 4th National Symposium of Shockwaves, February, Karunya Institute of Technology, Coimbatore, India.
17. Arun Kumar R and G Rajesh, 2016, "Diffuser Flow Characteristics During Vacuum Ejector-Diffuser Start-Up," 4th National Symposium of Shockwaves, February, Karunya Institute of Technology, Coimbatore, India.
16. Arun Kumar R and G Rajesh, 2015, "A Study on unsteady shear layer-shock Interaction in a vacuum ejector-diffuser system ," 30th International Symposium on Shockwaves, July, Ben-Gurion, Israel.
15. Vinod Yeldho Baby, and G Rajesh, 2015, "Experimental Study on the Interaction of Under Expanded Jets in Rarefied Flow Regimes," 30th International Symposium on Shockwaves, July, Ben-Gurion, Israel.
14. Arun Kumar R, G Rajesh, and Kim H D, 2015, "Flow characteristics of vacuum ejectors during start-up," 12th International Symposium on Experimental and Computational Aerothermodynamics of Internal Flows, July, Lerici, Italy.
13. G Rajesh, T. Hashimoto, and H. D. Kim, 2012, " CFD Analysis of the Compressible Flow in a Vortex Cup," Proceedings of 4th Asian Joint Workshop on Thermophysics and Fluid Science, October, Busan, Korea.
12. C. K. Muthukumaran, G Rajesh, H. D. Kim, 2012 , “A study on the unsteady aerodynamics of projectiles in overtaking blast flow fields,” 9th International Conference on Heat transfer, Fluid Mechanics and Thermodynamics, Italy, Malta.
11. Anand Raj Hariharan, S. Anil lal, Z. A. Samitha, G Rajesh, and P. Balachandran, 2010, “Thermal Mixing Analysis Of Three Lobed Clover Nozzle” 1st International Symposium on Mechanics, Materials and Management, January, College of Engg., Trivandrum, Kerala, India.
10. Fazil Mohammed, S. Anil lal, Z. A. Samitha, G Rajesh, and P. Balachandran, 2009, “A Parametric Study for the Optimization of a Supersonic Ejector,” The 20th International Symposium on Transport Phenomena, July, Canada
9. Anand Raj Hariharan, Z. A. Samitha, S. Anil lal, G Rajesh, and P. Balachandran, 2009 ,“Numerical Analysis of Thermal Mixing with Clover nozzle,” The 20th International Symposium on Transport Phenomena, July, Canada
8. G Rajesh, and H. D. Kim, “A Study on the Interior Ballistics of a Two-Stage Light-Gas Gun,” 2008, 2nd Asian Joint Workshop on Thermophysics and Fluid Science, May, Luoyang, China
7. G Rajesh, Suryakant Nagdewe, H. D. Kim, and T. Setoguchi, 2008, “Supersonic and Subsonic Projectile Overtaking Problems in Muzzle Gun Applications,” 4th Asian Joint Conference on Propulsion and Power, March, Daejon, Korea
6. G Rajesh, H. D. Kim, S. Matsuo, T. Setoguchi, and M. Deepu, 2008, “Computational Analysis of the Transient Flows in an Ejector-Diffuser System,” 12th Asian Congress on Fluid Mechanics, August, Daejon, Korea
5. G Rajesh, H. D. Kim, and Y. K. Lee, “Computational Study of the Operating Processes of a Ballistic Range,” 2008, 12th Asian Congress on Fluid Mechanics, August, Daejon, Korea
4. Rajesh, G. Pillai, H. G. Kang, H. D. Kim, and Suryakant Nagdewe, 2007 “Computational Study of the Unsteady Aerodynamics of the Projectile Overtaking a Moving Shockwave,” 7th Asian Computational Fluid Dynamics, November, Bangalore, India.
3. G Rajesh, R. Mishra, H. G. Kang, and H. D. Kim, 2007, “Computational Study of the Compressible Flow Driven by a Piston in the Ballistic Range,” 8th International Symposium on Experimental and Computational Aerothermodynamics of Internal Flows, July, Lyon, France
2. G Rajesh, H. D. Kim, T. Setoguchi, and S. Matsuo, 2006, “Optimization Study of a Coanda Ejector,” 1st Asian Joint workshop on Thermophysics and Fluid Sciences, June, Qufu, China
1. G Rajesh, H. G. Kang, H. D. Kim, and T. Setoguchi, 2006, “Theoretical and Computational Studies on Ballistic Range Performance,” 1st Asian Joint workshop on Thermophysics and Fluid Sciences, June, Qufu, China

Invited Talks


Shock Propagation and Transition on Air And Air-Water Interfaces , 7th Asian Joint Workshop on Thermal and Fluid Sciences, Thiruvananthapuram, Kerala, November 2018
Shock Reflections in Compressible Open jets, Vellore Institute of Technology, Vellore, March 2018
Shock Wave Technology: Future Prospects in Agri-Food sector, International Conference on Food Processing and Agribusiness-“Emerging Trends,” Indian Institute of Plantation Management, Bangalore, January 2018
Time resolved schlieren and shadowgraph techniques for high-speed flows, Rajalekshmi Engineering College, July 2017
High-Speed Imaging Techniques, College of Engineering Adoor, KUSAT, March 2017
Transitional Ballistics of Supersonic Projectiles, International Conference on Recent Advances in Aerospace Engineering, Karunya University, March 2017
Flow Visualization Techniques, Rajalekshmi Engineering College, August 2016
Mach Reflection Phenomenon in Open Jets, College of Engineering Adoor, KUSAT, January 2016
Transitional Ballistics, NIT Suratkal, September 2015

Courses Offered


IIT Madras
Fluid Mecahnics (Undergraduate)
Aerodynamics and Aircraft Performance (Graduate)
Gas Dynamics (Undergraduate)
Compressible Fluid Flow (Graduate)
Experimental Aerodynamics (Undergraduate)
Aerodynamic Design of Aircrafts (Graduate & Undergraduate)
Shockwave Dynamics (Graduate & Undergraduate)
Experimental Methods in Aero/Gas Dynamics (Graduate)
AeroLab I & II (Undergraduate)
Laboratory I (Graduate)
Keimyung University, South Korea
Fluid Mechanics
Thermodynamics
Introduction to Automotive Engineering
IIST, Thiruvananthapuram
Gas Dynamics
Aerodynamics
Thermodynamics
Engineering Mechanics
Aerodynamics Lab

People



Arun S

PhD Scholar (Jointly with Dr. A Sameen)
Research Topic: Computations of High-Speed Mixing layers

Sreelal M R

PhD Scholar
Research Topic: Blast Disturbances and Sabot Discard Process in Transitional Ballistics

Athira C M

PhD Scholar
Research Topic: Exansion Fan Diffraction over bodies of Various Configurations

Vinoth P

PhD Scholar
Research Topic: Shock Reflections in open jets and short wedges

Divia Harshavardini S

PhD Scholar (Jointly with Dr. Arul Prakash K)
Research Topic: Hypersonic Boundary Layer Transition

Sivaprasad G

PhD Scholar
Research Topic: Bistability in Suddenly Expanding High-Speed Confined Jets

Thara Reshma

PhD Scholar
Research Topic: Weak Shock Reflections in Pseudo-steady and unsteady flows

Shubham K Vyas

PhD Scholar
Research Topic:

Ijaz Ahamed

MS Scholar (Presently with LPSC, ISRO)
Research Topic: Flow Separation in Nozzles

Shobhan Roy

MS Scholar (Jointly with Dr. Santanu Ghosh)
Research Topic: Shock-Boundary Layer Interaction on Porous Surafces

Nitesh Sinha

MS Scholar (SCL, ISRO)
Research Topic: Micro-Nozzle Flows

Yousaf Saidalavi

Project Officer
OFC-ODC Project: CFD simulations of the flow through Muzzle brakes and Bore Evacuator Projectiles

Sushmitha J

Project Officer
OFC-ODC Project: CFD simulations of the flow through Muzzle brakes and Bore Evacuator Projectiles

Past



Dr. Arun Kumar R

INSPIRE faculty at Dept. of Aerospace Engineering, IISc

2005 - 2008
Ph.D
Mechanical Engineering
School of Mechanical Engineering
Andong National University
South Korea
1997 - 1999
Master of Technology
Mechanical Engineering
College of Engineering Trivandrum
University of Kerala
1990 - 1994
Bachelor of Technology
Mechanical Engineering
TKM College of Engineering
University of Kerela

2013 - present
Associate Professor
Dept. of Aerospace Engineering
IIT Madras
Chennai
2012 - 2013
Assistant Professor
Dept. of Mechanical and Automotive Engineering
Keimyung University
South Korea
2008 - 2012
Assistant Professor
Dept. of Aerospace Engineering
IIST, Valiamala
Thiruvananthapuram
2003 - 2008
Lecturer
Mechanical Engineering
Govt. Engineering College
Kerala
2001 - 2003
Scientist/Engineer
LPSC, ISRO
Valiamala
Thiruvananthapuram

Kerala

Aero-ballistic Range


The aero-ballistic range is used to accelerate projectiles of various configurations accelerated upto supersonic Mach numbers. The aero-ballictis range consists of a high pressure tube (HPT), a pump tube(PT) and a launch tube (LT). The HPT and PT are separated by thin plastic diaphragms (OHP sheet), and the PT and the LT are separated by a scored aluminium diaphrgam of thickness 0.9mm to 1.2mm. When the high pressure tube is given a pressure of 10 - 20 bar, the plastic diaphragm breaks which pushes the piston in the PT and the piston develops very high pressures (~200-300 bar) in the pump tube, and the aluminum diphragm is broken. LT flow is initiated and the projectile kept in the LT is accelerated to very high velocities. When the projectile comes out of the tube, the flow field is captured using time resolved schlieren or shadowgraph techniques.

Typical tests that are conducted in the aero-ballistic range are studies on shock-shock interactions, projectile-flow field interactions, unsteady aerodynamics of supersonic and transonic projectiles in transitional ballistic regimes, blast impact of steel and aluminium structures, etc.

gun1 gun1

Open Jet Facility


The open jet facility is fed from a 36 cubic meter, 10 bar reservoir. The stagnation chamber pressure is controlled by two pressure regulating valves (PRV) connected parallelly to acheive a maximum flow rate of 2kg/s. Typical tests that are conducted in this facility include, open jet studies in nozzle flow, ejector studies, etc.

openjet prv

High-speed imaging facilities


Schlieren system


The schlieren system consists of two no.s of 300mm diameter, 2000 mm focal length parabolic mirrors, a Newport 100W halogen light source, 150mm diameter, 450 mm focal length bi-convex lens and two high-speed cameras (IX-726 and Photron SA-4) with 3600 FPS at 1 MP, and a minimum exposure time of 259 ns, (Max. FPS: 1 Million) and 1 micro sec (Max. FPS: 0.6 million)

Some results


slide1