Ramjet Valve Assembly Thermal Insulation and EMC Reduction

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing ramjet propulsion systems for guided missiles face thermal issues due to engine burn-up, which can impair electronic control systems, and electromagnetic compatibility (EMC) problems from long electrical cable connections, affecting the missile's safe operation.

Innovation Solution

A ramjet propulsion system with a thermally isolated valve assembly housed within the engine structure, featuring an air-gap insulation and a compact, preassembled design that includes the valve assembly and control electronics, utilizing a lead screw servo motor with a lever arm for precise fuel metering and a semiconductor bridge circuit for efficient control, while minimizing mechanical and electrical interfaces.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Volume of moving object

If the valve assembly is placed close to the combustion chamber for compact design, then the missile structure becomes more compact, but the electronic components are exposed to high temperatures that can impair their operation

Engineering Contradiction:
Improvemissile structure compactnessVSAvoidtemperature exposure of electronic components
Core Design Contradiction:
Volume of moving objectVSTemperature

Solution Approach 1:

The valve assembly is segmented into two distinct parts: a thermally isolated valve unit housed within the engine structure, and separate electronic components positioned in a cooler zone. This segmentation allows the mechanical valve to be close to the combustion chamber while keeping electronics thermally protected, resolving the contradiction between compactness and thermal protection.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

A thermal barrier or insulating structure acts as an intermediary between the hot combustion chamber and the electronic components. This intermediary element enables the valve assembly to maintain compact positioning near the engine while preventing harmful thermal transfer to sensitive electronics, thus maintaining both compactness and operational reliability.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Temperature

If long electrical cable lengths are used to connect valve control to electronics, then the valve can be positioned for optimal thermal isolation, but electromagnetic compatibility problems arise affecting safe operation

Engineering Contradiction:
Improvethermal isolation of valve assemblyVSAvoidelectromagnetic compatibility
Core Design Contradiction:
TemperatureVSReliability

Solution Approach 1:

The valve control unit and electronic components are merged into a single integrated assembly positioned within the engine structure. This consolidation eliminates the need for long external cable connections, thereby maintaining thermal isolation while simultaneously resolving electromagnetic compatibility issues by minimizing cable length and interface points.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The integrated valve assembly serves multiple functions: it provides thermal isolation for the valve mechanism, minimizes electromagnetic interference through compact integration, and maintains control functionality. This multi-functional design resolves the contradiction by achieving thermal protection without sacrificing electrical connectivity or introducing EMC problems.

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

3Reliability

If a complex redesign of the guided missile is performed to centralize functions, then thermal and EMC problems are solved, but the device complexity and assembly difficulty increase

Engineering Contradiction:
Improvethermal and EMC protectionVSAvoidmissile redesign complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The valve assembly is designed as a pre-integrated unit with thermally isolated valve and control electronics already positioned and connected within the engine structure. This preliminary integration eliminates the need for complex post-assembly modifications or extensive missile redesign, as the assembly can be installed as a complete functional unit, thereby maintaining reliability improvements while minimizing added complexity.

Inventive Principle:
Principle #10Preliminary action

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 enhances thermal protection, reduces EMC issues, improves flight accuracy, and simplifies assembly and testing, resulting in a robust, compact, and efficient propulsion system with improved control properties.

Implementation Method 1

the valve assembly being thermally insulated, particularly by means of air gap insulation

Methodology Applied
Scientific EffectThermal insulation: Thermal Insulation

Data Source

PatentEP1967723B1Ramjet engine and guided missile with such a ramjet engine
Publication Date: 2019.06.12 MBDA DEUTSCHIAND GMBH
  • EP1967723B1 patent drawingFigure 1
  • EP1967723B1 patent drawingFigure 2
  • EP1967723B1 patent drawingFigure 3a

AI summary

A valve control unit for a ramjet propulsion system (2) with an engine cavity (3) and with a valve (6) for controlling a quantity of propellant required for the propulsion system, as well as with a valve actuator (7) which is designed to be actuated by a control electronics unit (8), is intended to have improved functionality. This is achieved by combining the valve (6) with its valve actuator (7) and its control electronics unit (8) into a thermally insulated valve assembly (10), wherein the valve assembly (10) is designed for arrangement in the engine cavity (3).