Defect-Free Paraffin Fuel Manufacturing

LWDC technology enables an improved channel wall nozzle with an outer liner that is fused to the inner liner to contain the coolant. It is an additive manufacturing technology that builds upon large-scale cladding techniques that have been used for many years in the oil and gas industry and in the repair industry for aerospace components. LWDC leverages wire freeform laser deposition to create features in place and to seal the coolant channels. It enables bimetallic components such as an internal copper liner with a superalloy jacket. LWDC begins when a fabricated liner made from one material, Material #1, is cladded with an interim Material #2 that sets up the base structure for channel slotting. A robotic and wire-based fused additive welding system creates a freeform shell on the outside of the liner. Building up from the base, the rotating weld head spools a bead of wire, closing out the coolant channels as the laser traverses circumferentially around the slotted liner. This creates a joint at the interface of the two materials that is reliable and repeatable. The LWDC wire and laser process is continued for each layer until the slotted liner is fully closed out without the need for any filler internal to the coolant channels. The micrograph on the left shows the quality of the bond at the interface of the channel edge and the closeout layer; on the right is a copper channel closed out with stainless.

Hybrid chemical motors offer an alternative to traditional liquid or solid motors for spacecraft, missiles, rockets, or other vehicles. The key advantage of a hybrid motor is the capability to throttle the motor via active control, which cannot be done in solid propellant motors. However, rapid throttling presents significant challenges to implement in practice. Here, NASA has combined a deep-throttling hybrid motor previously developed by Utah State University with a fast-acting digital valve design to produce a fast-acting, deep-throttling hybrid. Testing performed to-date using a prototype of the hybrid motor and digital valve design has shown the new hybrid motor to be capable of full-scale throttling twice as fast (1 second throttling compared to 2 seconds) as previous control valve designs. With optimization, there is potential full-range throttling may be further reduced to 0.5 second, a 4x improvement over previous control valve designs for hybrid motors. Additionally, smaller mid-range thrust changes have currently been measured in the 40:1 for relatively small motors (

NASA Glenn's fully premixed burner design accomplishes the rapid mixing of the fuel and air flows while simultaneously providing backside impingement cooling to the burner face. This novel burner technology has been demonstrated to operate on hydrogen-air mixtures at pressures up to 30 bar, and at equivalence ratios (Phi) ranging from 0.15 to 5.0, but typically at equivalence ratios below 0.6 or above 2.0 for extended periods of time. It has also been demonstrated to work well with hydrogen-carbon monoxide fuel mixtures in a 1:1 mixture (by volume). The design provides a uniform zone of combustion products and temperatures, and is able to achieve complete and rapid mixing of the reactant gases over a distance as short as 5 mm, with the combustion products attaining a fully-reacted state within about 10 mm downstream of the burner face. Effectiveness of the mixing is not dependent on the use of hydrogen gas, therefore the system works well for other gaseous fuels such as methane, propane, or natural gas, in a fully premixed mode. The design of the Glenn's burner is simple and straightforward to manufacture using conventional techniques. The modular design of the burner lends itself to scalability for larger power output applications. This burner is simple to operate and is robust for use in an industrial setting such as low-emissions stationary gas turbine engine, or for aircraft gas turbine engines.

Advances in new polymers and composites along with growing industrial needs in below-ambient temperature applications have brought about the Macroflash development. Accurate thermal performance information, including effective thermal conductivity data, are needed under relevant end-use conditions. The Macroflash is a practical tool for basic testing of common materials or research evaluation of advanced materials/systems. The Macroflash can test solids, foams, or powders that are homogeneous or layered in composition. Test specimens are typically 75mm in diameter and 6mm in thickness. The cold side is maintained by liquid nitrogen at 77 K while a heater disk maintains a steady warm-side temperature from ambient up to 373 K. The steady boiloff of the liquid nitrogen provides a direct measure of the heat energy transferred through the thickness of the test specimen. Nitrogen or other gas is supplied to the instrument to establish a stable, moisture-free, ambient pressure environment. Different compression loading levels can also be conveniently applied to the test specimen as needed for accurate, field-representative thermal performance data. The Macroflash is calibrated from approximately 10 mW/m-K to 800 mW/m-K using well-characterized materials.

Modular Artificial-Gravity Orbital Refinery Spacecraft is a solution for refining in-situ materials collected in space, such as from asteroids and Mars moons, as well as recycling spacecraft debris, while orbiting in micro-gravity conditions. The spacecraft is coupled with refining modules for refining and recycling different types of materials. It generates artificial gravity for operation in low-gravity environments. The spacecraft is comprised of rotating rings, each generating artificial gravity and angular momentum. When the rotating rings are combined on the spacecraft platform, however, they have a net near-zero angular momentum such that the spacecraft can change its attitude with minimal propellant or rotate at the rate of the object the spacecraft platform is attached to. The spacecraft platform can self-balance to accommodate different sized modules and modules with moving loads. The refined and recycled materials can be used to create products in-situ as well as products too large to launch from Earth, such as construction of orbiting space habitats, large spacecraft, solar-power stations, and observatories.