Design tasks

Write up analysis up until this point

Recalculate forces, dynamic pressures, and descent rates for updated rocket

Opening Shock Force (Potvin, 2)

$\begin{array}{l}\displaystyle F=C_k(C_dS)_0\frac{1}{2}\rho v^2\end{array}$

Stress in DGB (Clark and Tanner, 13)

$\begin{array}{l}\displaystyle \sigma t=\frac{F_{design}}{\pi D_{disk}}\end{array}$

Ripstop Nylon MIL-C-7020 (Poynter, 70)

Fabric, oz/yard	t, inches
1.1	.005
1.6	.006

Find drogue Cd

Maydew gives C_{d_0}= .53-.58, D_c/D₀ = .73, and D_p/D₀ = .65 (15).

Clark and Tanner say "It was typically assumed" that D_p/D₀ = 2/3 (12). They do not give C_danywhere, however they cite a number of papers that my give it.

Lingard has charts with Cd vs M for a number of geometric parameters (55-58). They range from .3-.6 in the subsonic range, .5-.2 in the transonic range, and .3-.5 in the supersonic range. I'm not sure what all of the geometric parameters are or what Cd is with respect to.

Size drogue

As of December 12, the mass budget says the rocket will be about 95lb dry.

Pick geometric ratios

Read Clark and Tanner.

Calculate stresses and forces in components

Pick fell and hem types

Calculate design factors

SRB drogue and main design factors (Maydew et al., 131)

Various DGB design factors (Clark and Tanner, 13)

I think Knacke has some design factor design guides

Calculate required textile strengths

Find most suitable cloths and tapes

Find suppliers and order textiles

See Parachute Suppliers.

Other tasks

Get design reviewed

Draw schematics

Determine proper assembly procedures

Create master list of construction details

Arrange wind tunnel test

Sources

Lingard. 09_Supersonic Parachute Aerodynamic Testing and Fluid Structure Interaction Simulation_Lingard.pdf. (n.d.). Retrieved from https://solarsystem.nasa.gov/docs/09_Supersonic%20Parachute%20Aerodynamic%20Testing%20and%20Fluid%20Structure%20Interaction%20Simulation_Lingard.pdf

Clark, I., & Tanner, C. (2017). A historical summary of the design, development, and analysis of the disk-gap-band parachute. In 2017 IEEE Aerospace Conference (pp. 1–17). https://doi-org.ezproxyberklee.flo.org/10.1109/AERO.2017.7943854

Maydew, R. C., Peterson, C. W., & Orlik-Rueckemann, K. J. (1991). Design and Testing of High-Performance Parachutes (La Conception et les Essais des Parachutes a Hautes Performances) (No. AGARD-AG-319). ADVISORY GROUP FOR AEROSPACE RESEARCH AND DEVELOPMENT NEUILLY-SUR-SEINE (FRANCE), ADVISORY GROUP FOR AEROSPACE RESEARCH AND DEVELOPMENT NEUILLY-SUR-SEINE (FRANCE). Retrieved from http://www.dtic.mil/docs/citations/ADA246343

Potvin, J. (2009). Updating and Upgrading the World’s Database on the Opening Shock Factor Ck. American Institute of Aeronautics and Astronautics. https://doi-org.ezproxyberklee.flo.org/10.2514/6.2009-2905

Poynter, D. (1984). The parachute manual: a technical treatise on aerodynamic decelerators (3rd ed., completely rev). Santa Barbara, CA: Para Pub.

Child pages

Disk-Gap-Band Design