Pyrotechnic Active Mass for Infrared Decoy Spectral Radiation
Solution Overview
Problem
Conventional pyrotechnic active materials for infrared targets are mechanically and thermally sensitive, have limited radiation output, and are not compatible with other chemicals, leading to safety issues and reduced effectiveness, especially at high air speeds.
Innovation Solution
A high-performance active mass composed of a fuel, oxidizer, and carbon-containing substance that achieves high radiation power in the B band with minimal A band radiation, is insensitive, and can be easily ignited, using a combination that includes natural materials like wood or brown coal, and oxidizers like potassium nitrate, to generate a non-sooting flame and maximize radiation output.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If ammonium perchlorate is used as oxidizer, then radiation output is achieved, but mechanical and thermal sensitivity increases leading to safety issues
Solution Approach 1:
The patent changes the chemical composition parameters by replacing ammonium perchlorate with potassium nitrate as oxidizer and using paraffin wax as fuel, fundamentally altering the combustion characteristics to achieve both safety and radiation performance
Solution Approach 2:
The invention creates a composite pyrotechnic composition combining potassium nitrate, paraffin wax, and iron powder in specific proportions, where each component contributes specific properties: potassium nitrate provides oxidation, paraffin provides fuel and spectral characteristics, and iron powder enhances radiation output
2Power
If conventional pyrotechnic composition is used, then radiation is emitted, but radiation output is relatively low and significant radiation is lost at high air velocities
Solution Approach 1:
The patent optimizes combustion temperature parameters by selecting paraffin wax with specific melting and combustion characteristics, maintaining temperatures in the range that maximizes B-band radiation while minimizing energy loss to convection and conduction at high velocities
3Ease of operation
If nitrocellulose-containing explosive is used, then combustion is achieved, but ignition requires strong ignition pulse producing non-spectral flash that reveals decoy target
Solution Approach 1:
The patent changes the ignition parameters by using a composition that ignites easily with weak signals and burns with a luminous flame characteristic of jet engines, eliminating the need for strong ignition pulses that produce revealing flashes
Solution Approach 2:
The invention utilizes the characteristic luminous flame color and spectral emission of paraffin combustion to match jet engine exhaust signature, making the decoy visually indistinguishable from real aircraft exhaust to infrared detection systems
4Productivity
If conventional explosives are used, then combustion is achieved, but density is limited to maximum of approximately 1500 kg/m3 reducing transport capacity
Solution Approach 1:
The patent creates a dense composite formulation where fine iron powder is distributed throughout the paraffin-wax-potassium nitrate matrix, achieving optimal packing density and maximizing the quantity of radiation-generating material that can be contained in dummy targets of given caliber
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 solution provides a radiation output exceeding conventional materials by three times, maintains effectiveness at high air speeds, and is insensitive enough to be classified as ammunition, with a simplified production process and reduced oxidizer content, achieving a precise spectral match to a jet engine.
Implementation Method 1
The substance is chosen such that it undergoes endothermic pyrolysis due to the heat released during the primary reaction, thereby releasing flammable gas in air, particularly with a soot-free flame
Implementation Method 2
the oxidizer can oxidize the fuel in an exothermic primary reaction, generating a temperature of at least 1000 K
Implementation Method 3
the oxidizer can oxidize the fuel in an exothermic primary reaction
Implementation Method 4
emits predominantly radiation with a wavelength of 3.5 to 4.6 μm, i.e., radiation in the so-called B-band
Data Source
AI summary
High performance active material comprises a fuel, an oxidizing agent, a binder and a substance containing carbon, where: the fuel and the oxidizing agent are selected such the oxidizing agent is oxidized to the fuel after its ignition in an exothermic primary reaction under the formation of a temperature of at least 1000 K; and the substance is selected such that the substance is endothermally pyrolyzed by the heat released during the primary reaction and releases flammable gas in air. High performance active material comprises a fuel, an oxidizing agent, a binder and a substance containing carbon, where: the fuel and the oxidizing agent are selected such that the oxidizing agent is oxidized to the fuel after its ignition in an exothermic primary reaction under the formation of a temperature of at least 1000 K; the substance is selected such that the substance is endothermally pyrolyzed by the heat released during the primary reaction and releases flammable gas in air; the redox potential of the fuel is at least as high as the redox potential of carbon; and the substance and its proportion are selected on the high-performance active material so that the temperature of the high performance active material does not exceed 2000 K after its ignition due to the heat extraction by pyrolysis, which takes place endothermally.