INSPIRE INSpiring Pressure gain combustion Integration, Research, and Education

ESR 15

Introduction and contact info:

Name: Gokkul Raj Varatharajulu Purgunan

Work address: TU Berlin, Straße des 17. Juni 135, 

10623 Berlin.


PhD project:

Title: Full gas dynamics and exergetic analysis of PGC cycles with rotating detonations

The PhD topic for ESR 15 is “Full Gas dynamics and exergetic analysis of PGC cycles with Rotating Detonations”.  The final expected result is the full cycle simulation of rotating detonation combustor (RDC) with the turbomachinery upstream and downstream of the combustor. The first task is to integrate the Turbine to the exhaust of the RDC using 1D unsteady Euler model. For the 1D Euler model, the source terms are calculated using mean-line analysis of turbine. Once, the turbine integration is done successfully, the compressor integration to RDC will be done. The procedure for compressor designing is similar to that of the turbine, that is, the compressor is modelled with unsteady 1D Euler model, and the source term for the 1D Euler, will be evaluated from mean-line analysis of compressor. The in-built code for RDC is 2D unsteady Euler model, and during the PhD, the reduced order model for the combustor will be derived from existing 2D unsteady Euler RDC model and CERFACS detailed 3D simulations. This reduced order model is aimed to develop in CERFACS during one of the secondments. This reduced order model will be integrated to the whole cycle model. Then, the secondary compressor will be modelled. The main role for the secondary compressor is to compress the air to the outlet pressure same as the RDC outlet pressure. The exhaust of the secondary compressor will be sent to the exhaust of the RDC in order to dampen the fluctuation before the burnt gas entering the turbine. The part of compressed air from secondary compressor will be used as bleed flow for the turbine blade cooling. Then, the second secondment (UNIGE) will be carried out to broaden the understanding on transient and time-dependent gas turbine simulation. Finally, having all the component modelled, a full cycle simulation will be carried out.

Supervisor:  Prof. Panagiotis Stathopoulos

Mentor: Prof. Alessandro Sorce

Planned secondments: 

  • CERFACS (M18 – M20) – Aim to develop the reduced order model for the rotating detonation combustor that will be integrated to the whole model.
  • UNIGE (M27 – M29) – To broaden the understanding on transient and time-dependent gas turbine simulations and assist the collegeaus there for the development of their own reduced order model for rotating detonation combustor.


  • Born in Chennai, India
  • Bachelors in AERONAUTICAL Engineering from Madras Institute of Technology, India (07/2014–04/2018).
  • Master in AERONAUTIQUE et ESPACE with specialization in Energetics and Propulsion from ISAE-ENSMA, France (09/2018 – 01/2021).

Personal interests: 

Sports (Cricket, squash, tennis), Cooking.

LinkedIn profile.

Research highlights: 

Results Obtained:

  • Meanline analysis of axial turbine to provide source terms for the unsteady 1D Euler turbine model.
  • The integration of unsteady 1D Euler model with the downstream of Rotating Detonation Combustor and validation with 3D CFD
  • Reduced order model for Optimization of Turbine to reduce the entropy generations and comparison with 3D CFD results.
  • Integration of film cooling in the unsteady 1D Euler turbine model using two new source terms and comparison with 3D CFD results (in collaboration with POLITO).
  • Quasi 1D and 0D modelling of Rotating Detonation Combustor (RDC) and comparison with high fidelity simulations and experimental results.
  • 0D ejector model downstream to RDC.
  • Steady state design point approach of TurboJet and TurboFan configuration with RDC.
  • Exergy analysis of all aircraft components
  • Incorporating film cooling into the in-house 2D RDC Euler solver
  • Part Load analysis of RDC-Turbojet configuration using the maps of NASA E3 High Pressure Compressor and High Pressure Turbine.
ESR1 – Choomanee Runnoo: Experimental investigation of Constant Volume Combustion and its reduced order model – ENSMA (FR), Supervisors: Prof. Marc Bellenoue and Bastien Boust
ESR2 Gregory Uhl: Numerical analysis of the interaction between a Rotating Detonation Combustor and an axial turbine – SAFRAN Tech (FR), Dr. Said Taileb, Prof. Marc Bellenoue, Prof. Thierry Poinsot,
ESR3 Nicola Detomaso: Simulation of CVC combustor – CERFACS (FR), Supervisors: Prof. Thierry Poinsot, , Dr. Davide Laera, Dr. Florent Duchaine
ESR4 Maria Clara de Jesus Vieira: Experimental characterization of ignition events in CVC like conditions – ENSMA (FR), Supervisors: Prof. Julien Sotton, Prof. Marc Bellenoue and Prof. Camille Strozzi
ESR5 Provence Barnouin: Control and impact of RDC wave direction – TUB (DE), Supervisors: Prof. Myles Bohon and Prof. Christian O. Paschereit
ESR6 – Patrick Strempfl: LES of flow and combustion in a rotating detonation engine coupled to a turbine – CERFACS (FR), Supervisor: Prof. Thierry Poinsot
ESR7 – Hongyi Wei: Experimental investigation of rotating detonation combustors including ignition processes and turbine-integration effects – TUB (DE), Supervisors: Prof. Myles Bohon and Prof. Christian O. Paschereit
ESR8Thomas Golliard: Computational aeroacoustics of the exhaust flow for noise assessment and control – KTH (SE), Supervisors: Prof. Mihai Mihaescu, Prof. Anders Dahlkild
ESR9 – Roseline Ngozi Ezekwesili: Deflagration-Autoignition-Detonation transition – TUB (DE), Supervisor: Prof. Myles Bohon and Prof. Marc Bellenoue
ESR10 – Shreyas Ramanagar Sridhara: Numerical modelling and optimization of cooling solutions for PGC concepts – UNIFI (IT), Supervisors: Prof. Antonio Andreini
ESR11- Umberto Sandri: Experimental study of cooling solutions for PGC concepts – UNIFI (IT), Supervisor: Prof. Bruno Facchini, Prof. Antonio Andreini, Dr. Alessio Picchi
ESR12 – Panagiotis Gallis: Unsteady numerical simulation of the interaction between pressure-gain combustors and high-pressure turbine stages – POLITO (IT), Supervisor: Dr. Simone Salvadori
ESR13 – Abhishek Dubey: power plant analysis and cycle thermo-economic optimization – UNIGE (IT), Supervisor: Prof. Alessandro Sorce
ESR14 – Sreenath Purushothaman: propulsion application with part load and dynamic analysis – UNIGE (IT), Supervisors: Prof. Alessandro Sorce, Prof. Alberto Traverso
ESR15 – Gokkul Raj Varatharajulu Purgunan: Full gas dynamic and exergetic analysis of PGC cycles with rotating detonations – TUB (DE), Supervisor: Prof. Panagiotis Stathopoulos