Hybrid-Cycle Rocket Engine Turbine Segmentation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current liquid propellant rocket engine technologies, such as gas generator and expander cycles, face inefficiencies due to partial propellant diversion for turbine power, resulting in lower thrust-to-weight ratios and increased atmospheric losses, as they either vaporize propellants or combust a portion for exhaust, limiting the use of propellants in generating thrust.

Innovation Solution

A hybrid rocket engine design that combines elements of gas generator and expander cycles, utilizing a gas generator to power pumps and turbines while also employing an expander cycle to increase combustion chamber pressure, allowing for higher thrust and efficient use of propellants by isolating and connecting turbines and pumps to optimize fuel and oxidizer flow, enabling operation as either a hybrid or expander cycle engine.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Power

If a gas generator process is used to power turbines, then thrust is generated, but a portion of each propellant is combusted in the gas generator and discarded as exhaust, reducing propellant efficiency

Engineering Contradiction:
ImprovethrustVSAvoidpropellant efficiency
Core Design Contradiction:
PowerVSLoss of substance

Solution Approach 1:

The rocket engine is divided into multiple independent turbine systems (first turbine for fuel pump, second turbine for oxidizer pump, third and fourth turbines for additional pumping) that operate separately. Each turbine is powered by its own portion of propellant combustion, allowing independent optimization of each power generation pathway and reducing the need to discard propellant for a single centralized gas generator.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The engine design incorporates multiple turbines that can simultaneously perform different functions: the first two turbines power the main fuel and oxidizer pumps, while the third and fourth turbines provide additional pumping capability. This multi-functional turbine system allows the engine to generate sufficient power while using propellants more efficiently across multiple pathways rather than sacrificing a large portion in a single gas generator.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Power

If propellants are vaporized by heating in the combustion chamber, then thrust is generated, but this method has limitations to the types of propellants used and the thrust generated

Engineering Contradiction:
ImprovethrustVSAvoidpropellant type compatibility
Core Design Contradiction:
PowerVSAdaptability or versatility

Solution Approach 1:

The engine design changes the thermal parameters by incorporating multiple turbine systems that can handle different temperature and pressure conditions. This allows the use of various propellant combinations with different thermal properties, as each turbine-propellant pathway can be optimized for specific propellant types, thereby increasing adaptability while maintaining thrust generation.

Inventive Principle:
Principle #35Parameter changes

3Quantity of substance

If mechanical pumps are used to pressurize propellants, then propellant flow is driven into the combustion chamber, but the pumps require power from turbines that consume propellant

Engineering Contradiction:
Improvepropellant flowVSAvoidpropellant consumption for power
Core Design Contradiction:
Quantity of substanceVSLoss of substance

Solution Approach 1:

The propellant flow system is segmented into multiple independent pumping pathways, each with its own turbine-powered pump. The first pump handles fuel pressurization with its dedicated first turbine, the second pump handles oxidizer pressurization with its dedicated second turbine, and additional pumps are supported by third and fourth turbines. This segmentation reduces the propellant sacrifice ratio by distributing power generation across multiple efficient pathways rather than using a single large gas generator.

Inventive Principle:
Principle #1Segmentation

4Device complexity

If a single turbine system is used to power pumps, then the system is simpler, but the thrust-to-weight ratio is lower and atmospheric losses increase

Engineering Contradiction:
Improveturbine system structureVSAvoidatmospheric losses
Core Design Contradiction:
Device complexityVSLoss of energy

Solution Approach 1:

The turbine system is divided into multiple independent units (first, second, third, and fourth turbines) that operate in parallel rather than as a single centralized system. Each turbine is mechanically connected to its specific pump, creating independent power pathways that reduce mechanical losses and improve overall efficiency, thereby reducing atmospheric losses while managing system complexity through modular design.

Inventive Principle:
Principle #1Segmentation

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The hybrid rocket engine achieves higher combustion chamber pressures, resulting in increased thrust and reduced atmospheric losses, with the ability to switch between modes to optimize performance during different phases of flight, such as liftoff and later stages of launch, ensuring efficient propellant use and improved rocket propulsion.

Implementation Method 1

combusting, at a gas generator, the first portion of the fuel and the first portion of the oxidizer to power the first pump and the second pump

Methodology Applied
Scientific EffectCombustion: Combustion

Implementation Method 2

The first pump is mechanically connected to a first turbine and the second pump is mechanically connected to a second turbine

Methodology Applied
Scientific EffectTurbine energy conversion: Turbine

Implementation Method 3

Propellants may be vaporized by heating, and thus expanding, the one or more propellants in a nozzle wall as combustion occurs in the rocket engine nozzle

Methodology Applied
Scientific EffectVaporization: Evaporation

Implementation Method 4

Propellants may be vaporized by heating, and thus expanding, the one or more propellants in a nozzle wall

Methodology Applied
Scientific EffectThermal expansion: Thermal Expansion

Implementation Method 5

pumping, at a first pump, a first portion of a fuel to a gas generator

Methodology Applied
Scientific EffectMechanical pumping: Pump

Implementation Method 6

combusting, at the combustion chamber, the second portion of the fuel and the second portion of the oxidizer to provide thrust from the nozzle

Methodology Applied
Scientific EffectCombustion: Combustion

Implementation Method 7

Liquid propellant rocket engines (LPREs) use a chemical reaction between one or more propellants under pressure to generate thrust to propel a vehicle

Methodology Applied
Scientific EffectRocket propulsion: Rocket

Data Source

PatentEP2971740B1Hybrid-cycle liquid propellant rocket engine
Publication Date: 2021.11.03 NORTHROP GRUMMAN SYSTEMS CORP
  • EP2971740B1 patent drawingFigure 1
  • EP2971740B1 patent drawingFigure 2
  • EP2971740B1 patent drawingFigure 3A

AI summary

Systems and methods are described herein for a hybrid liquid propellant rocket engine. In an embodiment, the engine includes a first pump powered by a first turbine, a second pump powered by a second turbine, and a gas generator. An output of the gas generator is connected to the first turbine and the second turbine. The engine further includes a third pump powered by a third turbine, a fourth pump powered by a fourth turbine, and a nozzle having an expander cycle in a wall and a combustion chamber. An output of the third pump is connected to the expander cycle and an output of the wall is connected to the third turbine and the fourth turbine. An output of the fourth pump, an output of the third turbine, and an output of the fourth turbine are connected to the combustion chamber.