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Ryan McDaniel

Publications and source records attributed to Ryan McDaniel.

The Adaptable, Deployable, Entry and Placement Technology (ADEPT) Enabling Advanced Entry, Descent, and Landing Capabilities for SmallSat Missions

The Adaptable, Deployable Entry and Placement Technology (ADEPT) is a mechanically deployable low-ballistic coefficient aeroshell entry system which performs entry, descent, and landing (EDL) functions for a broad range of planetary destinations including Mars, Venus, Titan and Earth. The deployable system allows mission planners to develop an aeroshell design that is stowed like a folded umbrella, and yet prior to the EDL mission segment, transforms into a deployed, near-rigid low ballistic coefficient configuration. The ADEPT architecture is scalable from a sub-1m class to 6m diameter entry vehicles for Venus and and it has been studied at up to 15m – 20m scale for human exploration class missions. There has been growing interest in performing interplanetary missions with small spacecraft as secondary payloads and ADEPT offers small satellite mission designers the ability to consider Aeroassist technologies to expand mission applications. The ADEPT architecture introduces a new approach for entry vehicle design. It deploys a flexible 3D woven carbon fabric as the primary drag surface. It is capable of surviving high aerothermal heating during entry, while maintaining a robust impermeable membrane that provides high drag for vehicle deceleration. The ADEPT project team has advanced this decelerator technology via systems-level testing at the one meter diameter (nano-ADEPT) scale. A subsonic aeroloads test (May 2015) and a pathfinder arc-jet aeroheating test (Sept 2015) and a successful sounding rocket flight (SR-1) launch of a 0.7 meter deployed diameter ADEPT (September 2018). The SR-1 flight experiment demonstrated most of the primary end-to-end mission stages including: launch in a stowed configuration, separation and deployment in zero-g, exo-atmospheric conditions, and passive ballistic re-entry of a 70 degree half-angle cone geometry. The ADEPT SR-1 sounding rocket flight experiment had to address challenges such as stowing within the constrained payload envelope, fabric folding, and packaging concerns.

Paul Wercinski↗

Magnetohydrodynamic and Aerodynamic Assessment of Ballistic Entry of a 70deg Spherecone at Mars and Venus

An electrical conductivity database for continuum flow in a CO2 atmosphere over a 70 deg spherecone was created using the Data Parallel Line Relaxation Code computational fluid dynamics software to inform development of future magnetohydrodynamic subsystems at Venus and Mars. Sixteen freestream conditions were considered at Mars with atmospheric relative velocities from 5 to 8 km/s and altitudes between 20 and 80 km. Sixteen freestream conditions were considered at Venus with atmospheric relative velocities from 9 to 12 km/s and altitudes between 85 and 115 km. Results indicate that the total electrical conductivity in the flow volume always increases as velocity increases. At low velocities, the electrical conductivity is higher at high altitudes, while at high velocities, the electrical conductivity is higher at low altitudes. Three of the 80 km altitude computational fluid dynamics solutions show good agreement with Direct Simulation Monte Carlo results. In general, computational fluid dynamics predicts thinner shocks, higher electron number density, and similar vibrational temperatures as direct simulation Monte Carlo. The magnetohydrodynamic force was calculated at both Mars and Venus. Results indicate there may not be sufficient control authority to use magnetohydrodynamics as a trajectory control mechanism at Mars without artificially increasing the electrical conductivity of the flow, but there may be appreciable control authority for a drag-modulated aerocapture at Venus.

Destiny M Fawley↗

Aerothermal Analysis and Environment Predictions for the Mars Sample Retrieval Lander (SRL)

Mars Sample Retrieval Lander (SRL) is the next mission to Mars, and an integral part of the proposed Mars Sample Return (MSR) Program. Aerothermal Analysis of the SRL capsule takes advantage of the design and analysis of the Mars Science Laboratory and the Mars 2020 missions, findings from the MEDLI and MEDLI2 heatshield instrumentation campaigns, and developments in predictive capabilities over the last 20 years. In particular, SRL is being designed to enter the Mars atmosphere at velocities as high as 8 km/s, which would be the highest for a Mars entry, and is expected to encounter additional shock layer radiation physics compared to previous missions to Mars. This paper presents the status of analysis including the overall methodology, models and assumptions of the aerothermal environment predictions, with a focus on differences from the approaches and modeling used for Mars 2020 and MSL.

Mars↗

Aerothermal Analysis and Environment Predictions for the Mars Sample Retrieval Lander (SRL)

Mars Sample Retrieval Lander (SRL) is the next mission to Mars, and an integral part of the proposed Mars Sample Return (MSR) Program. Aerothermal Analysis of the SRL capsule takes advantage of the design and analysis of the Mars Science Laboratory and the Mars 2020 missions, findings from the MEDLI and MEDLI2 heatshield instrumentation campaigns, and developments in predictive capabilities over the last 20 years. In particular, SRL is being designed to enter the Mars atmosphere at velocities as high as 8 km/s, which would be the highest for a Mars entry, and is expected to encounter additional shock layer radiation physics compared to previous missions to Mars. This paper presents the status of analysis including the overall methodology, models and assumptions of the aerothermal environment predictions, with a focus on differences from the approaches and modeling used for Mars 2020 and MSL.

Mars↗