11/18/2018 Development of Cryogenic Engine for GSLV MkIII: Technological Challenges RS Praveen, N Jayan, KS Bijukumar, J Jayaprakash, V Narayanan, G Ayyappan Liquid Propulsion System Centre Vikram Sarabhai Space Centre ISRO Propulsion Research Complex Department of Space, INDIA ICEC-26

Contents Introduction and Background Cryogenic Engine Schematic and operational features Technological Challenges and adopted approach methodology Concluding remarks. 11/18/2018 ICEC-26, NEW DELHI

Introduction and Background High thrust Upper Stage Cryogenic Engine and 2 MW Power Liquid hydrogen fuel and Liquid oxygen oxidiser Gas Generator Cycle for development easiness Chilling requirement in ground and during flight prior to operation. Regenerative Cooling 10 Hot tests cumulative duration of approximately 1900s 11/18/2018 ICEC-26, NEW DELHI

Technological Challenges Design and realization of the sub systems viz the thrust chamber, the gas generator, the liquid hydrogen and liquid oxygen turbo pumps. System engineering of the engine with given envelope constraints and mass budget in the launch vehicle. Ignition of the engine thrust chamber in the tank head mode Sustained and stable combustion. Passive thrust control system using pressure regulator and cavitating venturi combination Mixture Ratio Control using re-circulation flow Boot strap mode starting using stored gaseous hydrogen. Development of flight sequence including chilling requirements of feed circuits Testing and qualification. 11/18/2018 ICEC-26, NEW DELHI

Sub-System Design and Realization 11/18/2018 ICEC-26, NEW DELHI

Thrust Chamber Development 11/18/2018 Thrust Chamber Development Atomization and vaporization Reaction and mixing Thermal loads Nozzle Performance Stability Testing LH2 Inlet Spacer Assembly Thrust Chamber Assembly LOX Inlet High Pressure Valves Cavitating Venturies 11/18/2018 ICEC-26, NEW DELHI ICEC-26

Turbo Pump System Sizing Dual Stage for LH2 Single Stage for LOX Independent Turbines and Power Management Critical Speed Bearings and Seals Testing 11/18/2018 ICEC-26, NEW DELHI

Integrated Engine Envelope, mass and moment of inertia Interface Joints Start Sequence Development Chilling Requirements Testing 11/18/2018 ICEC-26, NEW DELHI

Concluding Remarks This is the first time that a cryogenic engine that operates in gas generator cycle capable of delivering a thrust of 20T has been developed by ISRO. The technological challenges faced during the various phases of development were briefly highlighted in the paper. 11/18/2018 ICEC-26, NEW DELHI

THANK YOU 11/18/2018 ICEC-26, NEW DELHI