Kana Yoshida1,2, Reha Avsar3, Aaron Hartmann3, Taro Kanai4, Takafumi Sasaki4, Kenji Takizawa4 and Tayfun E. Tezduyar3
1Department of Mechanical Engineering, Tottori University, Tottori, Japan. 2TOMODACHI STEM Program @ Rice University, Houston, Texas, USA.3Mechanical Engineering, Rice University, Houston, Texas, USA. 4Department of Modern Mechanical Engineering, Waseda University, Tokyo, Japan.
Structural Mechanics Computation of the Orion Spacecraft
Drogue Parachute in Compressible-Flow Regime
Methods and Conditions
Base Computation (Case 0)
Pressure Dependence
Time Resolution Effect
Orion spacecraft parachute sequence From NASA site
Drogue parachutes
Compressible flow
Main parachutes
Incompressible flow
Background- Orion Drogue Parachute
Drop test From NASA site
Cost is about a million dollar for
each test.
Wind-tunnel test From NASA site
Scaling challenge due to coupling
between the canopy deformation
and the airflow.
- Field Tests
Computational analysis
can serve as a practical alternative.
• How the solution and the solution process vary
→ Pressure : Parachute diameter and vertical position change.
→ Dt : Computing time can be reduced by increasing Dt.→ η : The settled shapes are close, but η =140 s-1 leaves out movement
details, which are actually not needed.
• Larger time-step size?
→ With larger Dt, we can reach the settled shape sooner, with
almost the same shape as in Case 0, but with less computing time.
References[1] K. Takizawa, T.E. Tezduyar, and R. Kolesar, “FSI modeling of the
Orion spacecraft drogue parachutes, Computational Mechanics,
Vol. 55, pp.1167-1179, 2015.
[2] K. Takizawa, T.E. Tezduyar, and T. Kanai, “Porosity models and
computational methods for compressible-flow aerodynamics of
parachutes with geometric porosity”, Mathematical Models and Methodsin Applied Sciences, DOI: 10.1142/S0218202517500166, 2017.
This research was conducted as part of the 2017 TOMODACHI STEM @ Rice
University Program which is funded by a grant from the TOMODACHI Initiative, a
program of the US–Japan Council. For more information on TOMODACHI program,
see http://tomodachistem.rice.edu/. We are grateful to Tatsuya Tanaka for using
some of the background material from his poster.
- Governing Equations
Structural mechanics equations
- Spatial Discretization
Finite element method
Parachute configuration [1]
Mach number 0.5
Altitude (ft) 35,000
Base conditions
• Case 3 parachute shape settles sooner than Case 0.
• Case 3 parachute shape is almost the same as it was in Case 0.
• Case 4 parachute shape settles even sooner than Case 3.
• Case 4 parachute shape is almost the same as it was in Case 0.
• Larger time-step sizes save computing time.
• Parachute canopy in Case 1 is positioned lower than it was in Case 0.
• Parachute diameter in Case 1 is smaller than it was in Case 0.
Case 1 Case 2
Case 3 Case 4
Case 0 results look reasonable. We test
• different pressures
• different time-step sizes (Dt)• different structural damping coefficients (η)
to see how the settled parachute shape changes.
• Obtain deformed parachute shape for fluid computations of the
Orion drogue parachute [1] in compressible-flow regime [2]
• Study the pressure dependence and effect of time-step size, and
damping coefficient
• Mesh resolution effect
• Fluid computations with the deformed shape
Pressure (Pa) Dt (s) η (s-1)
1,000 0.001 0
Pressure (Pa) Dt (s) η (s-1)
1,500 0.002 0
Pressure (Pa) Dt (s) η (s-1)
1,500 0.003 0
• Parachute canopy in Case 2 is positioned higher than it was in Case 0.
• Parachute diameter in Case 2 is larger than it was in Case 0.
Pressure (Pa) Dt (s) η (s-1)
1,500 0.001 0
Pressure (Pa) Dt (s) η (s-1)
3,000 0.001 0
Case 0 (76.0% D0) Case 4 (76.8% D0)Case 3 (76.4% D0)
Initial shape (D0 = 23 ft)
Settled shape (76.0% D0)
Objective
Case 0 (76.0% D0) Case 1 (75.6% D0) Case 2 (76.8% D0)
Acknowledgement
Conclusions
Damping Effect
Case 5 Case 6
• Parachute movement in Case 5 is close to what it was in Case 0.
• Movement details in Case 6 are not captured, but not needed.
• Settled parachute diameter in both cases is close to what it was in Case 0.
• Initial movement in both cases is different from what it was in Case 0.
• The settled shape is almost the same.
Pressure (Pa) Dt (s) η (s-1)
1,500 0.001 14
Pressure (Pa) Dt (s) η (s-1)
1,500 0.001 140
Future Directions
Case 5 (76.2% D0) Case 6 (76.3% D0)Case 0 (76.0% D0)