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The Naval Research Laboratory (NRL) was challenged to determine the maximum size and configuration of a fuel producing process on the remote island of Diego Garcia using electricity from renewable sources such as wind and solar. D...
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The Naval Research Laboratory (NRL) was challenged to determine the maximum size and configuration of a fuel producing process on the remote island of Diego Garcia using electricity from renewable sources such as wind and solar. Data from renewable site assessments of Diego Garcia conducted by the National Renewable Energy Laboratory (NREL) and the Naval Facilities Engineering Command ( NAVFAC) have been used in this report to support an economic basis for the littoral production of low carbon fuel from carbon dioxide (CO2) and hydrogen (H2) in seawater. Diego Garcia represents one of the most difficult challenges to the U.S. Navy for the future production of low carbon fuel from renewable electrical energy from photovoltaic (PV) arrays and wind turbines due to its extremely small land area and Class II wind classification. This study uses this remote base as a detailed example of the many possible sites and scenarios that could be utilized for the proposed littoral land-based process. The maximum size and configuration of a fuel producing process on Diego Garcia using electricity from renewable sources such as wind and solar is detailed.
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An electrochemical acidification cell was developed and tested as a method for extracting large quantities of CO2 from seawater for use as a feedstock for jet-fuel synthesis at sea. After the technology was successfully demonstrat...
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An electrochemical acidification cell was developed and tested as a method for extracting large quantities of CO2 from seawater for use as a feedstock for jet-fuel synthesis at sea. After the technology was successfully demonstrated in the laboratory, it was scaled-up and integrated into a mobile skid design. This report details the results of four separate evaluations (January 22-27, April 25-29, July 11-5, August 28-September 1) of the electrochemical acidification cell performance as a function of pH, current, time, polarity reversal, and CO2 and H2 recovery.
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The effects water mist has on the overpressures produced by the detonation of 50 lb equivalent of high explosives (HE) TNT, Destex, and PBXN- 109 in a chamber is reported. The overpressures for each charge density were measured wi...
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The effects water mist has on the overpressures produced by the detonation of 50 lb equivalent of high explosives (HE) TNT, Destex, and PBXN- 109 in a chamber is reported. The overpressures for each charge density were measured with and without mist preemptively sprayed into the space. The impulse, initial blast wave, and quasi-static overpressure measured in the blast mitigation experiments were reduced by as much as (40%, 36%, and 35%) for 50 lbs TNT, (43%, 25%, and 33%) for 50 lbs TNT equivalent Destex, and (49%, 39%, and 41%) for 50 lbs TNT equivalent PBXN-109 when water mist was sprayed 60 seconds prior to detonation at a concentration of 70 g/m sup3 and droplet Sauter Mean Diameter (SMD) of 54 micrometer. These results suggest that current water mist technology is a potentially promising concept for the mitigation of overpressure effects produced from the detonation of high explosives.
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Strong base anion exchange resins were studied to determine if they could be used as a feasible and practical method for sequestering carbon dioxide from seawater for use as a carbon feedstock in a sea-based fuel production proces...
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Strong base anion exchange resins were studied to determine if they could be used as a feasible and practical method for sequestering carbon dioxide from seawater for use as a carbon feedstock in a sea-based fuel production process. Static and dynamic flow experiments to determine the resin bicarbonate and chloride selectivity and the effect of ionic strength on bicarbonate selectivity and capacity are reported. These data are used to determine the scaled up feasibility of a carbon capture process by this approach.
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NRL's Navy Technology Center for Safety and Survivability recently initiated a full-scale fire test series to demonstrate the efficacy of high expansion foam for protecting large volume shipboard spaces. High expansion foam was pu...
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NRL's Navy Technology Center for Safety and Survivability recently initiated a full-scale fire test series to demonstrate the efficacy of high expansion foam for protecting large volume shipboard spaces. High expansion foam was pursued because of its inherent ability to travel around obstructions, fill the volume in minutes, and provide a three-dimensional firefighting capability that would not depend on a manual firefighting attack to complete final extinguishment. In addition, it can accomplish all this by using only a small quantity of liquid solution, which results in reduced water damage and minimal clean-up after its use. The demonstrated success of this NRL fire test series has helped to generate considerable interest within the Navy's ship design community for incorporating high expansion foam systems into future surface ship designs.
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The hydrogenation of CO2 using a traditional Fischer-Tropsch Co- Pt/Al2O3 catalyst for the production of valuable hydrocarbon materials is investigated. The ability to direct product distribution was measured as a function of diff...
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The hydrogenation of CO2 using a traditional Fischer-Tropsch Co- Pt/Al2O3 catalyst for the production of valuable hydrocarbon materials is investigated. The ability to direct product distribution was measured as a function of different feed gas ratios of H2 and CO2 (3:1, 2:1, and 1:1) as well as operating pressures (ranging from 450 to 150 psig). As the feed gas ratio was changed from 3:1 to 2:1 and 1:1, the production distribution shifted from methane toward higher chain hydrocarbons. This change in feed gas ratio is believed to lower the methanation ability of Co in favor of chain growth, with possibly two different active sites for methane and C2-C4 products. Furthermore, with decreasing pressure, the methane conversion drops slightly in favor of C2- C4 paraffins. Even though under certain reaction conditions product distribution can be shifted slightly away from the formation of methane, the catalyst studied behaves like a methanation catalyst in the hydrogenation of CO2.
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New ship manning concepts have resulted in new demands and changing roles for personnel assigned to damage control. The changing force structure requires that designers and operators understand the capabilities of damage control t...
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New ship manning concepts have resulted in new demands and changing roles for personnel assigned to damage control. The changing force structure requires that designers and operators understand the capabilities of damage control teams. This includes the design, equipment, and doctrinal requirements needed for an acceptable level of ship recoverability. Limited formal structures and validated methods for assessing such capabilities exist. Methods to assess readiness and training requirements suffer from a lack of quantitative or validated approaches. This paper describes the use of manned damage control modeling techniques and readiness assessments to provide a more rational basis to assess damage control manning.
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The development of the DC-ARM Supervisory Control System (SCS) is discussed. The SCS is used to provide situational awareness of a ship casualty to the operator through a variety of means. The SCS currently interfaces and controls...
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The development of the DC-ARM Supervisory Control System (SCS) is discussed. The SCS is used to provide situational awareness of a ship casualty to the operator through a variety of means. The SCS currently interfaces and controls the ship's automated fire main, outfitted with smart valves, a high- pressure water mist system, a video over IP system, a door position indication system, and environmental sensors. Testing aboard the SHADWELL demonstrated that situational awareness can be achieved within 5 seconds after the casualty and that automatic fire boundary containment can be completed within 25 seconds. The SCS can also automatically reconfigure damaged ship systems (such as a ruptured fire main) in approximately 1 minute.
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The complications posed by smoke disrupt all facets of the damage control (DC) problem onboard ships. Smoke will reduce visibility, which causes disorientation and deterioration of communications among the ship's crew. In turn, th...
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The complications posed by smoke disrupt all facets of the damage control (DC) problem onboard ships. Smoke will reduce visibility, which causes disorientation and deterioration of communications among the ship's crew. In turn, the ability of the ship's crew to restore vital ship mission capability will be impeded. In practice, desmoking is generally not implemented until after the fire is under control. With this approach, the benefits gained from minimizing smoke levels in the earlier stages of the event are not realized. For the design of future Navy ships, it is essential to identify the performance requirements for smoke control and to design systems according to these requirements. Installed smoke control systems will become more important on ships with reduced manning since there will be fewer people available to implement manual techniques This report describes a shipwide system that could be installed on ships of the future.
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Tests were conducted to evaluate the level of performance of commercially available optical fire detectors for use in Navy aircraft hangars. Detectors were evaluated based on response to fuel spill fires and to optical stresses (i...
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Tests were conducted to evaluate the level of performance of commercially available optical fire detectors for use in Navy aircraft hangars. Detectors were evaluated based on response to fuel spill fires and to optical stresses (i.e., potential false alarm sources). The results of the fire detection evaluation have been combined with false alarm immunity criteria into a new optical detector performance specification for Navy aircraft hangars.
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