Propulsive Descent Technologies (PDT): Original Content Project

&lt;p&gt;Future missions to Mars require landed mass that exceeds the capability of current entry, descent, and landing technology.&amp;nbsp; 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.&lt;/p&gt;&lt;p&gt;One possible technology to enable future high mass missions to Mars is the use of retro propulsion during the entry phase.&amp;nbsp; 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.&lt;/p&gt;&lt;p&gt;The project will seek to partner with a commercial launch provider to obtain flight data.&amp;nbsp; The data acquired by the proposed government-commercial partnership are expected to include the following aerosciences products:&lt;/p&gt;&lt;ul&gt;&lt;li&gt;Vehicle state (position, velocity, attitude, attitude rates, etc.)&lt;/li&gt;&lt;li&gt;Temperatures, heating rates, and pressures on the vehicle&amp;rsquo;s outer skin&lt;/li&gt;&lt;li&gt;Imagery provided by NASA and its contractors, in addition to vehicle propulsion system performance data.&lt;/li&gt;&lt;/ul&gt;&lt;p&gt;&amp;nbsp;&lt;/p&gt;&lt;p&gt;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.&amp;nbsp; The commercial partner&amp;rsquo;s engines will be properly scaled in the CFD calculations using established scaling parameters with varying degrees of exhaust modeling fidelity.&amp;nbsp; Solutions will be completed on custom grids for each CFD code using geometries provided by the commercial partner.&lt;/p&gt;&lt;p&gt;Objectives (for each code):&lt;/p&gt;&lt;ol&gt;&lt;li&gt;Establish computational requirements (grid, run time, number of CPUs, etc.) and the effects of turbulence modeling and time-accurate simulations on results&lt;/li&gt;&lt;li&gt;Examine varying levels of engine exhaust modeling (perfect gas vs. simulated gas vs. multi-specie gas)&lt;/li&gt;&lt;li&gt;Provide best practices for obtaining grid-converged solutions (flow initialization, time step requirements, grid adaptation, etc.)&lt;/li&gt;&lt;li&gt;Make blind comparisons of the &amp;ldquo;best&amp;rdquo; solutions with the flight data set(s), including flight imagery provided by NASA&lt;/li&gt;&lt;/ol&gt;&lt;p&gt;&amp;nbsp;&lt;/p&gt;&lt;p&gt;The PDT project will also develop vehicle configurations that support landing of a 2 metric ton (t) article on the Mars surface.&amp;nbsp; Project representatives will develop trajectories and supersonic retro propulsion profiles for the vehicle configurations using the CFD models.&amp;nbsp; The project will investigate interactions between vehicle subsystems, structures and thermal protection, the Mars aero environment, mass and center of gravity, and control techniques.&amp;nbsp; &amp;nbsp;&lt;/p&gt;

Tags: active, johnson-space-center, project
Organization: National Aeronautics and Space Administration