{"@type": "dcat:Dataset", "accessLevel": "public", "bureauCode": ["026:00"], "contactPoint": {"@type": "vcard:Contact", "fn": "Stephen Gaddis", "hasEmail": "mailto:stephen.w.gaddis@nasa.gov"}, "description": "<p>Future missions to Mars require landed mass that exceeds the capability of current entry, descent, and landing technology.  New technology and techniques are required to increase atmospheric entry and landing capabilities for high mass items. This capability is needed in order to enable future human-precursor and human-scale missions to Mars.</p><p>One possible technology to enable future high mass missions to Mars is the use of retro propulsion during the entry phase.  Supersonic retro propulsion involves using thrusters directed in opposition to the oncoming airflow to decelerate the entry vehicle while it is traveling at supersonic speeds.</p><p>The project will seek to partner with a commercial launch provider to obtain flight data.  The data acquired by the proposed government-commercial partnership are expected to include the following aerosciences products:</p><ul><li>Vehicle state (position, velocity, attitude, attitude rates, etc.)</li><li>Temperatures, heating rates, and pressures on the vehicle’s outer skin</li><li>Imagery provided by NASA and its contractors, in addition to vehicle propulsion system performance data.</li></ul><p> </p><p>Available NASA Computational Fluid Dynamics (CFD) tools will be exercised at a few select conditions during the SRP burn for each flight data set in order to provide insight into how the models compare against the data.  The commercial partner’s engines will be properly scaled in the CFD calculations using established scaling parameters with varying degrees of exhaust modeling fidelity.  Solutions will be completed on custom grids for each CFD code using geometries provided by the commercial partner.</p><p>Objectives (for each code):</p><ol><li>Establish computational requirements (grid, run time, number of CPUs, etc.) and the effects of turbulence modeling and time-accurate simulations on results</li><li>Examine varying levels of engine exhaust modeling (perfect gas vs. simulated gas vs. multi-specie gas)</li><li>Provide best practices for obtaining grid-converged solutions (flow initialization, time step requirements, grid adaptation, etc.)</li><li>Make blind comparisons of the “best” solutions with the flight data set(s), including flight imagery provided by NASA</li></ol><p> </p><p>The PDT project will also develop vehicle configurations that support landing of a 2 metric ton (t) article on the Mars surface.  Project representatives will develop trajectories and supersonic retro propulsion profiles for the vehicle configurations using the CFD models.  The project will investigate interactions between vehicle subsystems, structures and thermal protection, the Mars aero environment, mass and center of gravity, and control techniques.   </p>", "distribution": [{"@type": "dcat:Distribution", "downloadURL": "http://techport.nasa.gov/xml-api/13594", "format": "XML", "mediaType": "application/xml"}], "identifier": "TECHPORT_13594", "issued": "2013-10-01", "keyword": ["active", "johnson-space-center", "project"], "landingPage": "http://techport.nasa.gov/view/13594", "modified": "2025-03-31", "programCode": ["026:000"], "publisher": {"@type": "org:Organization", "name": "Space Technology Mission Directorate"}, "references": ["http://techport.nasa.gov/doc/home/TechPort_Advanced_Search.pdf", "http://techport.nasa.gov/fetchFile?objectId=3447", "http://techport.nasa.gov/fetchFile?objectId=3448", "http://techport.nasa.gov/fetchFile?objectId=3456", "http://techport.nasa.gov/fetchFile?objectId=6560", "http://techport.nasa.gov/fetchFile?objectId=6561", "http://techport.nasa.gov/fetchFile?objectId=6584", "http://techport.nasa.gov/home"], "temporal": "2013-10-01T00:00:00Z/2015-09-01T00:00:00Z", "title": "Propulsive Descent Technologies (PDT): Original Content Project"}