Jet Propulsion Device Bypass System for High Injection Pressure

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing two-propellant jet propulsion devices face limitations in achieving high specific thrust due to the need for turbopumps to be actuated by the expansion of the same propellant, which restricts the injection pressure and thrust, and require complex separation of highly reactive propellants.

Innovation Solution

A bypass system is implemented downstream of the turbopumps, where only a secondary flow of each propellant is used to actuate the turbopumps, with the main flow directly injected into the propulsion chamber, and secondary thrusters are connected to the turbines, allowing for lower pressure expansion and separate control of propellant supply.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Power

If the entire flow of each propellant is expanded in the turbine of each turbopump before injection into the propulsion chamber, then the turbopumps can be actuated by propellant expansion, but the injection pressure and specific thrust remain limited

Engineering Contradiction:
Improvespecific thrustVSAvoidpropellant flow path configuration
Core Design Contradiction:
PowerVSDevice complexity

Solution Approach 1:

The propellant flow is divided into two separate paths: a first path where a portion of the propellant flows through the heat exchanger and turbine to actuate the turbopump, and a second path where the remaining propellant flows directly to the propulsion chamber. This segmentation allows the main propellant flow to reach high pressure without being expanded in the turbine, while still using a portion of the flow to drive the pump.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Instead of using the entire propellant flow to actuate the turbine, only a portion of the propellant is diverted through the heat exchanger and turbine. The majority of the propellant bypasses the turbine expansion and goes directly to the propulsion chamber, maintaining high pressure and enabling higher specific thrust.

Inventive Principle:
Principle #16Partial or excessive action

2Power

If highly reactive propellants are used to increase specific thrust, then the injection pressure can be increased, but complex separation of propellants from combustion gases is required in each turbopump

Engineering Contradiction:
Improveinjection pressureVSAvoidpropellant separation system
Core Design Contradiction:
PowerVSDevice complexity

Solution Approach 1:

The turbine actuation function is extracted from the main propellant flow path. A separate branch is created that diverts a portion of the propellant through the heat exchanger and turbine, while the main propellant flow continues directly to the propulsion chamber without encountering combustion gases or requiring separation mechanisms.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The heat exchanger serves as an intermediary component that preheats the propellant before it enters the turbine, improving turbine efficiency without requiring direct contact between the propellant and combustion gases. This intermediary arrangement allows high-pressure propellant to actuate the turbine while maintaining propellant purity.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Power

If turbopumps are used to supply propellants at very high pressure to increase specific thrust, then the injection pressure increases, but the proximity of propellants in the turbopump creates safety concerns

Engineering Contradiction:
Improveinjection pressureVSAvoidpropellant separation reliability
Core Design Contradiction:
PowerVSReliability

Solution Approach 1:

The propellant delivery system is segmented into separate flow paths: one path for propellant actuation through the turbine and another path for direct delivery to the propulsion chamber. This physical separation eliminates the proximity issue in the turbopump, as the main propellant flow does not pass through the turbine chamber where combustion gases are present.

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

This configuration enables higher injection pressure and specific thrust in the propulsion chamber while maintaining efficient propellant separation and orientation control, enhancing the overall performance and efficiency of the jet propulsion device.

Implementation Method 1

heat exchangers are integrated through which at least one of the liquid propellants passes, in order to cool the walls of the propulsion chamber while preheating at least one part of the propellant

Methodology Applied
Scientific EffectHeat exchange: Heat Exchanger

Implementation Method 2

the expansion of a gas in the turbine actuates the pump

Methodology Applied
Scientific EffectGas expansion: Pressure Gradient

Implementation Method 3

a single turbine drives two pumps, one for each propellant

Methodology Applied
Scientific EffectTurbine operation: Turbine

Implementation Method 4

turbopumps are typically used to supply the propulsion chamber with propellants at very high pressure

Methodology Applied
Scientific EffectHydraulic compression: Hydraulic Press

Data Source

PatentEP2766591B1Jet propulsion device and fuel supply method
Publication Date: 2015.09.16 SN DETUDE & DE CONSTR DE MOTEURS DAVIATION (S N E C M A)
  • EP2766591B1 patent drawingFigure 1

AI summary

The invention relates to the field of jet propulsion devices, and in particular to a jet propulsion device (1) in which a first supply circuit (6), that supplies a main thruster (4) with a first fuel, has, downstream of the pump (8b) of a first turbopump (8), a branch-off (13) through a first regenerative heat exchanger (10) and the turbine (8a) of a first turbopump (8), a branch-off (13) through a first regenerative heat exchanger (10) and the turbine (8a) of a first turbopump (8), and a second supply circuit (7), for supplying the main thruster (4) with a second fuel, has, downstream of the pump (9b) of a second turbopump (9), a branch-off through a second regenerative heat exchanger (11) and the turbine (9a) of the second turbopump (9). The device (1) also comprises at least one secondary thruster (15) connected downstream of the turbines (8a, 9a) of the first and second turbopumps (8, 9).