Extreme environment simulation - current and new capabilities to simulate Venus and other planetary bodies

Abstract

Science, technology, and planetary mission communities have a growing interest in components and systems that are capable of working in extreme (high) temperature and pressure conditions. Terrestrial applications range from scientific research, aerospace, defense, automotive systems, energy storage and power distribution, deep mining and others. As the target environments get increasingly extreme, capabilities to develop and test the sensors and systems designed to operate in such environments will be required. An application of particular importance to the planetary science community is the ability for a robotic lander to survive on the Venus surface where pressures are nearly 100 times that of Earth and temperatures approach 500C. The scientific importance and relevance of Venus missions are stated in the current Planetary Decadal Survey. Further, several missions to Venus were proposed in the most recent Discovery call. Despite this interest, the ability to accurately simulate Venus conditions at a scale that can test and validate instruments and spacecraft systems and accurately simulate the Venus atmosphere has been lacking. This paper discusses and compares the capabilities that are known to exist within and outside the United States to simulate the extreme environmental conditions found in terrestrial or planetary surfaces including the Venus atmosphere and surface. The paper then focuses on discussing the recent additional capability found in the NASA Glenn Extreme Environment Rig (GEER). The GEER, located at the NASA Glenn Research Center in Cleveland, Ohio, is designed to simulate not only the temperature and pressure extremes described, but can also accurately reproduce the atmospheric compositions of bodies in the solar system including those with acidic and hazardous elements. GEER capabilities and characteristics are described along with operational considerations relevant to potential users. The paper presents initial operating results and concludes with a sampling of investigations or tests that have been requested or expected.

Materials properties characterization in the most extreme environments

“…215,216 The Glenn Extreme Environments Rig (GEER) can simulate many planetary environments include high temperature and high pressure along with multicomponent chemistry within a 0.914 m (3 ft.) diameter and 1.219 m (4 ft.) length. 217 Due to NASAs current interest in Venus, 218 GEER has been configured to mimic the Venusian atmosphere at the surface to about 75 km high. GEER can mimic the surface for more than 24 days with the following parameters: 773 K, 100 bar, CO 2 -96.5%, SO 2 -130 ppm, HF-5 ppm, HCl-0.5 ppm, NO-5.5 ppb, CO-15 ppm, COS-27 ppm, N 2 -3.4%, and H 2 O-30 ppm for 24 days.…”

“…GEER can mimic the surface for more than 24 days with the following parameters: 773 K, 100 bar, CO 2 -96.5%, SO 2 -130 ppm, HF-5 ppm, HCl-0.5 ppm, NO-5.5 ppb, CO-15 ppm, COS-27 ppm, N 2 -3.4%, and H 2 O-30 ppm for 24 days. 217 Figure 3e shows samples being loaded into GEER. Several materials have been tested for survivability and durability, including electronics packaging materials (PbO, Al 2 O 3 ), insulation (rock wool: CaO/ SiO 2 ), SiC electronics (Au/Pt/Ir/Pt/TaSi2 bondpads, Au wires, Pt wires), feed-through materials (ceramawire), SiC pressure sensors, 219 and Inconel 625.…”