PhD Proposal by Kenneth A Hart

Event Details
  • Date/Time:
    • Monday April 29, 2019
      1:00 pm - 3:00 pm
  • Location: Montgomery Knight 317
  • Phone:
  • URL:
  • Email:
  • Fee(s):
    N/A
  • Extras:
Contact
No contact information submitted.
Summaries

Summary Sentence: A MICROMECHANICALLY-INFORMED MODEL OF THERMAL SPALLATION WITH APPLICATION TO PROPULSIVE LANDING

Full Summary: No summary paragraph submitted.

Ph.D. Thesis Proposal

by

Kenneth A. Hart Jr.

(Advisor: Prof. Julián J. Rimoli)

 

A MICROMECHANICALLY-INFORMED MODEL OF THERMAL SPALLATION WITH APPLICATION TO PROPULSIVE LANDING

 

1:00 PM, Monday, April 29th, 2019

Montgomery Knight 317

 

 

ABSTRACT:

During the propulsive landing of spacecraft, the retrorocket exhaust plume introduces the landing site surface to significant pressure and heating. Landing site materials include concrete on Earth and bedrock on other bodies, two highly brittle materials. During a landing event, defects and voids in the material grow due to thermal expansion and coalesce, causing the surface to disaggregate or spall. After a spall is freed from the surface, the material beneath it is exposed to the pressure and heat load until it spalls, continuing the cycle until engine shutdown. Spalls and debris entrained in the exhaust plume risk damaging the lander or nearby asserts- a risk that increases for larger engines. A micromechanically-informed model of thermal spallation is developed to improve understanding of this process, in the context of propulsive landing. Initially a simulation of landing site spallation was developed, utilizing an empirical model for flame jet spallation drilling through granite. Granite, however, has a fundamentally different microstructure compared to typical landing sites, necessitating a more general approach. To that end, highly-detailed simulations of thermomechanical loading are applied representative microstructures. An algorithm has been developed to generate statistically representative microstructures and has been validated for a wide variety of materials, including basalt from Gusev Crater, Mars. Next steps are to analyze the behavior of such microstructures under various landing-relevant loading conditions. 

 

 

 

COMMITTEE MEMBERS:

· Dr. Julian J. Rimoli (advisor)

· Dr. Robert D. Braun

· Dr. Claudio Di Leo

· Dr. George A. Kardomateas

· Dr. Charles H. Campbell - NASA Johnson Space Center

Additional Information

In Campus Calendar
No
Groups

Graduate Studies

Invited Audience
Faculty/Staff, Public, Graduate students, Undergraduate students
Categories
Other/Miscellaneous
Keywords
Phd proposal
Status
  • Created By: Tatianna Richardson
  • Workflow Status: Published
  • Created On: Apr 17, 2019 - 10:26am
  • Last Updated: Apr 17, 2019 - 10:26am