AIR BREATHING HYPERSONIC PROPULSION

Kiran Babu K MDepartment of Aeronautical Engineering

Karpagam Institute of Technology, Coimbatore – 641 105.

Introduction to Hypersonic Air Breathing Propulsion

Hypersonic Vehicles Supersonic Combustion and Need for

Supersonic Combustion for Hypersonic Vehicles Problems Associated with Supersonic

Combustion Engine/Airframe Integration Aspects of

Hypersonic Vehicles Various types of Scramjet Combustors Fuel Injection Schemes in Scramjet Combustors One Dimensional Models for Supersonic

Combustion using method of influence coefficients.

What is Hypersonic Speed?

“Hypersonic speed refers to the speeds above MACH No 5,

with molecular dissociation and ionization due to high temperature at high speeds”

The peculiar characteristics of flow at hypersonic speeds are, Shock Layer Aerodynamic Heating Entropy Layer Real Gas Effects Low Density Effects Independence of Aerodynamic Coefficients with Mach Number

SCRAMJET

SCRAMJET is a variant of air breathing ramjet engine with the combustion taking place at the supersonic speeds.

Advantages◦ Does not have to carry oxygen◦ No rotating parts makes it easier to manufacture than a turbojet◦ Has a higher specific impulse than a rocket engine; could provide

between 1000 and 4000 seconds, while a rocket only provides 450 seconds or less

◦ Higher speed could mean cheaper access to outer space in the future

Disadvantages◦ Difficult / expensive testing and development◦ Very high initial propulsion requirements

The Specific Impulse of various Propulsion Systems

SCRAMJET TEST RUN

Critical Challenges in Development of SCRAMJET

EngineSupersonic combustion ramjet engine for an air-

breathing propulsion system has been realized and demonstrated by USA on ground and in flight. X- 43 vehicle used hydrogen fuel.

Critical challenges involved in the development of SCRAMJET Engine are,

Mixing of Fuel, Ignition and Flame Holding in Combustor

Ground Test Facilities and Numerical Simulations

SCRAMJET ENGINE FUELS

Hypersonic Vehicles

Boeing X-51 - WAVE RIDER

W14 - Missile

HSDTV

Proposed Single Stage to Orbit Launch

Issues in Hypersonic Air Breathing Propulsion

Challenges of Hypersonic Air Breathing Propulsion

Airframe Integrated Scramjet Design Challenges

Design Methods and

Optimization

Experimental Facilities, Measurements and Test

Methodology

Flight Testing

Challenges of Hypersonic Air Breathing Propulsion

Operating Efficiently and Reliably over a extraordinary range of Flight Conditions.

Accomplishing stable and efficient mixing of fuel for supersonic combustion within a burner of reasonable size.

Providing the necessary structural integrity for reusable systems operating at the extreme environmental conditions

Developing the tools that enable confident control over the engine design and reliable prediction of the actual behavior of the system.

Developing the facilities that enable vehicle and engine ready for routine operations by means of ground testing and flight testing of the experimental vehicles.

Engine/Airframe Integration

Engine/Airframe Integration

Aspects of Hypersonic Vehicles