Turbo-RocketA brand new class of hybrid rocket

Rene Nardi and Eduardo Mautone

53rd AIAA/SAE/ASEE Joint Propulsion Conference –July 10–12, 2017 - Atlanta, Georgia

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Background

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• Using liquid propellants rockets for educational purpose

has proven elusive for a very long time.

• Academic rocketry relies mostly on solid propellants, in

part to avoid the complexity of liquid propellants rockets.

• As long as the operation is restricted to the lower limits of

the atmosphere, airbreathing is an option worthing further

investigation.

Atmosphere Layers

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5 km

National Center for Atmospheric Research

Turbo Rocket

Why a liquid-gas hybrid ?

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The rocket should fly high enough to justify the

efforts, but it may not have to leave the atmosphere.

High subsonic speed is desirable, however, this

rocket may not necessarily go supersonic.

Jet engines are far simpler, safer and less expensive

to operate than rockets.

No cryogenic system to deal with:

no liquid oxygen, no helium, no high pressure vessels.

Why a liquid-gas hybrid ?

LRE SystemTurboRocket System

The TurboRocket is a brand new class of flying machine

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It does not operate as a jet aircraft, neither does it like a regular rocket.

JET AIRCRAFT TURBO-ROCKET

Horizontal take off Near vertical take off

Flies at the horizontal position Flies on the vertical

At the same altitude Always changing altitude

At constant speed Always changing velocity

Engine power set to idle

(cruise)

Engine at full power

The TurboRocket is a brand new class of flying machine

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It does not operate as a jet aircraft,

neither does it like a regular rocket.

ROCKET TURBO-ROCKET

Carries its working fluid in the

form of fuel and oxidizer.

Carries its own fuel, but relies on

the surrounding atmosphere as the

source of oxygen.

It is capable of operating within or

outside the atmosphere.

Operation limited to the confines

of the lower atmosphere.

Thrust is not affected, much, by an

increase in altitude.

Noticeable thrust reduction as

function of altitude.

High propellant mass fraction

( 80 %)

Low propellant mass fraction

( 5 % )

The TurboRocket is a brand new class of flying machine

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High Level Requirements

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• Design, build and launch a flying machine,

• To carry a 1 kg payload to 5 km ASL,

• Using a comerciall off-the-shelf turbojet engine,

• COTS electronics and sensors,

• With a composite structure (carbon fiber).

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Turbo-Rocket – overview

Turbo-Rocket in Details

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Nose Cone

Parachute

Payload

Flight Computer

Fins

Fuselage

Fuel Tank

Electronic Engine

Control Unit

Engine

Engine Cowling

A Turbojet Engine

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➢Total Weight of 2,6 kg for a Maximum Thrust of 300 N,

➢Nice thrust to weight ratio of 11:1

➢Liquid Rocket Engine at 30:1

➢Burning kerosene at a mass rate of 13 g/sec,

➢Specific Fuel Consumption of 1.6 lb/lbf.s

➢Liquid Rocket Engine at 10 lb/lbf.s.

A Turbojet Engine

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Jet-Cat 300

Engine Installation in Details

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Engine Installation Fuel Tank Installation

Performance simulations: Methodology

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➢Flight path divided into 3 portions

1 - Powered flight;

2 – Coasting;

3 - Descent

Performance simulations - Euler’s Method

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➢1 - Powered flight;

➢ Find the theoretical velocity and altitude increment,

without drag, over a small interval of time.

➢ Add this theoretical increment to the velocity in the

last interval and determine the drag.

➢ The drag is them substituted back into the original

force equation and the actual velocity increment

computed from the equation thus generated.

Performance simulations - restrictions

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Performance simulations: Equations

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Performance with 1 kg payload

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Performance simulations - results

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Specific Requirements I

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Altitude: 10,000 ft ( 3 km)

Payload: 8.8 lb ( 4 kg )

Class: COTS Hybrid (liquid – gas)

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Y(t) Altitude (m) V (t) Speed (m/s)

Spaceport America and IREC

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150 m/s

Powered Flight Coasting

What’s next ?

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• Incremental steps designed to improve the

concept and to, eventually, enhance performance.

1. Aerospike for a supersonic nozzle

2. Air intake design optimization to reduce drag

3. Afterburning, for higher speed and altitude

4. Thrust vectoring

5. Vertical landing

QUESTIONS ?

Thank you.

Rene Nardi

renenardi@hotmail.com

+1 912 405 6453

+55 12 98251 8864