The objective of this project was to theoretically and practically establish the feasibility of an electronic system that can be applied as a signal flare with a selectable wavelength and a reduced environmental impact. In particular this project focused on the power source technology that is required to drive a so-called electronic signal flare (E-Flare). This focus was chosen because the power source is the most technically challenging subsystem of the E-Flare, considering both environmental and technical aspects.
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 (even beyond the visual spectrum), the signal does not produce harmful combustion products and its function does not require perchlorate reactants.
Steps were taken to investigate the technical and environmental feasibility of an E-Flare. System requirements for an E-Flare were drafted and summarized in an Operational Concept Statement and preliminary designs were considered. In parallel, a semi-quantitative sustainability and environmental impact assessment was performed to compare the hazards and environmental impacts of the new to be developed E-Flare technology with those of conventional references (based on available information) and to assess the pros and cons and their causes in the underlying subsystems.
A first demonstrator was designed, built and tested based on these requirements, in a scaled laboratory breadboard experiment. A major part of the design process was the design and development of the pyrotechnic power source and the heat conversion into luminous power. The E-Flare design used commercial off the shelf (COTS) thermoelectrical generators (TEG) and light emitting diode (LED) for this proof of concept.
Based on the requirements several hypothetical E-Flare demonstrator designs were investigated based on possible performance, operational conditions and environmental aspects. Besides the selection and tuning of the pyrotechnic compositions for the power source, the dissipation of heat imposed further design challenges. The performed life cycle assessment was used as a guidance and not as a qualitive outcome, as design parameters are still too fluid. A more detailed and extensive life cycle analysis should be performed while further optimizing the design of the prototype. A demonstration experiment showed the conversion of heat from a pyrotechnic power source into luminous power by means of COTs TEGs and LEDs, and with that demonstrated the feasibility of the E-Flare concept.
An electronic signaling flare is expected to be a more environmentally friendly system than the traditional flare, with possible longer shelf-life characteristics. Additionally, the E-Flare could produce highly customizable signals, e.g. selecting colors or light patterns.