Cryostat-100

The Cryostat-500 provides laboratory measurement of the steady-state thermal transmission properties of thermal insulation systems under conditions below ambient temperature. Liquid nitrogen is used as a direct measure of the energy going through the test specimen. Thermal insulation systems may be composed of one or more materials that may be homogeneous or non-homogeneous at boundary conditions from 77 K to 373 K and in environments from high vacuum (10E-7 torr) to ambient pressure (10E+3 torr). The Cryostat-500 provides a much wider range of thermal performance and covers the full range of environmental conditions for applications below ambient temperature. The instrument has been proven through extensive testing of foams, composite panels, multilayer insulation (MLI) systems, aerogel blankets, fiberglass, and many other types of materials. Both the quality and quantity of the thermal performance data for insulation materials and systems have increased even as the process and method has become more time efficient and cost effective. Further guidelines on the test method and equipment for the Cryostat-500 are given in ASTM C1774, Annex A3.

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.

NASA's TVS Augmented Injector includes an internal heat exchanger, a fluid injector spray head, and an external surface condensation heat exchanger - all combined with multiple intertwined flow paths containing liquid, two-phase, and gaseous working fluid. The TVS provides a source of coolant to the injector, which chills the incoming fluid flow. This cooled flow promotes condensation of the tank ullage dropping pressure and maintains incoming fluid flow. The system eliminates the potential for a stalled fill condition and reduces tank pressure during cryogenic fluid transfer. During fill operations, the tank vent can be closed early in the process before fluid is introduced, and, in some cases, the tank vent may not even need to be opened. Furthermore, the TVS Augmented Injector can remove sufficient thermal energy to reach a 100% liquid level in the receiver tank. A cryo-cooler can be used in place the TVS flow circuit for a zero-loss system. The TVS Augmented Injector couples internal fluid flow cooling and external surface ullage gas condensation into a single, compact package that can be mounted to small tank flanges for minimal impact insertion into any vessel. The injector is printed as one part using additive manufacturing, resulting in part count reduction, improved reproducibility, shorter lead times, and reduced cost compared to conventional approaches. The injector may be of particular interest in applications where cryogenic fluid is expensive, fluid loss through vents is problematic, and/or achieving high filling levels would be helpful. The injector can benefit typical cryogenic fluid transfer between containers or, alternatively, can serve as a tank pressure control device for long-term storage using a fluid recirculation system that pumps fluid through the injector and sprays cooled liquid back into the tank. Additionally, where ISRU processes are employed, the injector can be used to liquefy incoming propellant streams.

Space and ground launch support related hardware often operate under extreme pressure, temperature, and corrosive conditions. When dealing with this type of equipment, it is frequently necessary to run wiring, tubes, or fibers through a barrier separating one process from another with one or both operating in extreme environments. Feedthroughs used to route the wiring, tubes, or fibers through these barriers must meet stringent sealing and leak tightness requirements. This affordable NASA feedthrough meets or exceeds all sealing and leak requirements utilizing easy-to-assemble commercial-off-the-shelf hardware with no special tooling. The feedthrough is a fully reconfigurable design; however, it can also be produced as a permanent device. Thermal cycling and helium mass spectrometer leak testing under extreme conditions of full cryogenic temperatures and high vacuum have proven the sealing capability of this feedthrough with or without potting (epoxy fill) on the ends. Packing material disks used in the construction of the device can be replaced as needed for rebuilding a given feedthrough for another job or a different set of feeds if potting is not used for the original feedthrough build. (Potting on one or both sides of the sleeve provides double or triple leak sealing protection). Variable Compression Ratio (VCR) connectors were adapted for the pressure seal on the feedthrough; however, any commercial connector can be similarly adapted. The design can easily be scaled up to larger (2" diameter) and even very large (12" or more) sizes.

Even when a water conformal fluid reservoir and drink straw are zipped into a down suit, water freezes under extreme conditions. This poses a health hazard, particularly to high-altitude climbers who mouth-breathe, as mouth-breathing causes substantial fluid loss (in exhaled breaths). Climbers of 8,000-meter peaks get only 1 liter or less of fluid on summit days because their drink bottles freeze so quickly. The High Altitude Hydration System keeps water from freezing in three different ways. First, the system has passive thermal control that uses aerogel insulation on the outside of the conformal fluid reservoir and around the drinking straw to protect the contents from the cold. The container is placed within an inner layer of clothing, and the insulated straw is pulled out from underneath the suit for sips. Second, the system has a braided copper wire placed around the exterior of the drinking straw and another heat-collecting surface about the container wall to transfer body-generated heat to the fluid reservoir and straw during use. Third, the system uses a microcontroller and tape heater powered by a battery to keep the straw warm and free of ice crystals.