Enabling Thermal Solutions for Future Laser Weapon Systems

TECH FOCUS AREAS: Directed Energy TECHNOLOGY AREAS: Electronics; Materials; Air Platform; Battlespace OBJECTIVE: Perhaps the most critical obstacle limiting the scalability of Laser Weapon Systems is rugged, low volume and weight thermal dissipation architectures. Lightweight, compact system thermal management begins in the laser source itself. DESCRIPTION: High Energy Laser Weapon Systems must perform in a highly transient environment with periodic short duration engagements in a rugged military environment in ground or air vehicles. Given current and projected efficiencies, a 300kWo class laser would require dissipating in excess of 600kWt of heat. For a 30s engagement magazine this equals 18MJt of energy to store or reject. Current laser source thermal architectures are not able to take advantage of the lightweight, compact thermal solutions that are currently being developed, largely due to issues such as low-quality heat and high flow rates within the laser source itself. The following ideas are suggestive, not prescriptive. Any solution within the laser source for enabling lightweight, compact and rugged thermal architectures for High Energy Laser Weapon Systems is of interest. Areas of interest include but are not limited to: Two-phase coolant systems Common loop' cooling solutions High-temperature diodes Novel heatsink materials and geometries Vapor chamber cooling Low-flow, low pressure solutions Lightweight, high efficiency/performance pumps Passive thermal transient management. Combinations of the above approaches are also of interest. All solutions must take into account system level efficiencies and requirements of High Energy Laser Weapon Systems. PHASE I: Offerors will propose a specific set of thermal management improvements and conduct design and feasibility study to validate assertions of high energy laser weapon system level SWaP improvement. PHASE II: A successful phase II proposal will demonstrate technical feasibility at the system level by: -Construction of a TRL 4 prototype of the technology in question -Creation of a final report detailing the design and creation of said prototype -An outline of the "next-steps" needed to advance the prototype technology, as well as various paths said advances could take -A concept of how the prototype technology would fit into an HEL system architecture. PHASE III DUAL USE APPLICATIONS: Phase III will build a drop-in upgrade to an existing ground or airborne high energy laser weapon system that will enhance existing capability of that system. NOTES: The technology within this topic is restricted under the International Traffic in Arms Regulation (ITAR), 22 CFR Parts 120-130, which controls the export and import of defense-related material and services, including export of sensitive technical data, or the Export Administration Regulation (EAR), 15 CFR Parts 730-774, which controls dual use items. Offerors must disclose any proposed use of foreign nationals (FNs), their country(ies) of origin, the type of visa or work permit possessed, and the proposed tasks intended for accomplishment by the FN(s) in accordance with section 5.4.c.(8) of the Announcement and within the AF Component-specific instructions. Offerors are advised foreign nationals proposed to perform on this topic may be restricted due to the technical data under US Export Control Laws. Please direct questions to the Air Force SBIR/STTR Help Desk: usaf.team@afsbirsttr.us REFERENCES: Tim Newell, et al. (2020) COMPACT HIGH ENERGY LASER ENGINEERING ASSESSMENT (CHELSEA), AFRL-RD-PSTR- 2020-0027 Josh Rothenberg. (2020) COMPACT HIGH ENERGY LASER ENGINEERING ASSESSMENT (CHELSEA), AFRL-RD-PSTR- 2020-0029; Dale Parkes, et al. (2020) COMPACT HIGH ENERGY LASER ENGINEERING ASSESSMENT (CHELSEA), AFRL-RD-PSTR- 2020-0028 (search CHELSEA on DTIC to find the above, all Distribution Limited); Sean Ross, Travis Michalak. (2016) Laser-thermal interface parameters. Internal Briefing (available on request from Dr. Ross or myself) KEYWORDS: Two-phase coolant systems; Common loop' cooling solutions; High-temperature diodes; Novel heatsink materials and geometries; Vapor chamber cooling; Low-flow, low pressure solutions; Lightweight, high efficiency/performance pumps; Passive thermal transient management