- Program Areas
- Installation Energy and Water
- Environmental Restoration
- Munitions Response
- Resource Conservation and Resiliency
- Weapons Systems and Platforms
Feasibility of a Thermoelectric Generator for a Reduced Environmental Impact Electronic Flare
Dr. Joost van Lingen | TNO
Electronic signal flare technology can address concerns involving the use of conventional flares. As opposed to conventional flares, the color of the electronic signal can be changed on demand, the signal does not produce harmful combustion products and its function does not require perchlorate reactants. Because of the use of an electronic signal light the risk for the operator being exposed to hot surfaces
is reduced as is the risk of starting wildfires.
This project aims to identify the technical and environmental feasibility of an electronic signal flare (EFlare). An E-Flare has a LED array providing the signal light. It is driven by a power source based on chemical heat generation and thermoelectrical conversion of this heat into electrical power. Technically and environmentally the biggest challenge for an E-Flare is expected to be its power source. Conventional electrochemical batteries would pose an environmental threat and lack the desired shelf life. Reserve batteries and thermal batteries are impractical and expensive. Development of a pyrotechnically driven thermoelectric generator may be a solution for this challenge, therefore this will be the focus of this project. A technology demonstrator will be developed and tested.
System requirements for an E-Flare will be drafted in a limited set of use cases and summarized in an Operational Concept Statement (OCS). This OCS provides the requirements to be met by the E-Flare technology demonstrator, taking into account environmental aspects and the properties of conventional flares. The demonstrator will be designed, built, and tested based on these requirements.
Parallel with, and providing input to the design process, the overall life cycle environmental impact of the E-Flare technology will be compared with conventional flares. Pros and cons and their causes in the underlying subsystems will be assessed. To this end, a quantitative life cycle scan will be made of the previewed E-Flare with its subsystems to provide input during the design phases. The result of this work will drive the selection of design options.
A major part of the design process will be the design and iterative development of the power source. The power source will use thermoelectrical generators (TEGs) selected based on their functional performance and environmental properties. TEGs convert thermal power into electrical power by virtue of the Seebeck effect. Combustion of pyrotechnical compositions will provide the required heat. These compositions will be selected and tuned to the optimal working temperatures of the TEGs. The performance of the power source will be characterized and assessed for conformance to stated requirements.
The design of the LED array including the required electronic circuits, will be based on COTS elements. Performance of the LED array will be characterized and assessed against stated requirements. When all subsystems conform to stated requirements, the demonstrator system will be integrated and tested for conformance to the higher-level System requirements, resulting in a more comprehensive feasibility statement for an E-Flare.