Direct Thrust Efficiency for the L’Garde Sail Surface with a Linear Reflectivity Model

Greschik, Gyula

doi:10.1007/978-3-642-34907-2_28

Cited by 2 publications

(6 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The main sources of this optical anisotropy are wrinkles on the solar sail membrane Wong and Pellegrino (2006a);Jenkins (2006). One special case of the effects of wrinkles on the solar sail efficiency was studied by Greschik (2014).…”

Section: Introductionmentioning

confidence: 99%

Light radiation pressure upon an optically orthotropic surface

Nerovny

Lapina

Grigorjev

2017

Journal of Quantitative Spectroscopy and Radiative Transfer

View full text Add to dashboard Cite

Abstract. In this paper, we discuss the problem of determination of light radiation pressure force upon an anisotropic surface. The optical parameters of such a surface are considered to have major and minor axes, so the model is called an orthotropic model. We derive the equations for force components from emission, absorption, and reflection, utilizing a modified Maxwell's specular-diffuse model. The proposed model can be used to model a flat solar sail with wrinkles. By performing Bayesian analysis for example of a wrinkled surface, we show that there are cases in which an orthotropic model of the optical parameters of a surface may be more accurate than an isotropic model.

show abstract

Section: Introductionmentioning

confidence: 99%

Light radiation pressure upon an optically orthotropic surface

Nerovny

Lapina

Grigorjev

2017

Journal of Quantitative Spectroscopy and Radiative Transfer

View full text Add to dashboard Cite

show abstract

“…At 1 AU from the sun, the value for P is 4.563 µN/m 2 [21]. Additionally, this can be assumed constant with solar activity, as the effect of solar activity on solar irradiance is minimal [22].…”

Section: Figure 8 Light Pressure On Solar Sailmentioning

confidence: 99%

“…This model, termed the linear photonic thrust model, drops all terms with Lambertian radiator coefficients. This is shown in the equations below [21]:…”

Section: Figure 8 Light Pressure On Solar Sailmentioning

confidence: 99%

“…Additionally, in most cases this approximation results in similar values to the nominal optics model. It has been shown that with worst-case values for degradation and incidence angle, the error from this approximation only reaches about 10% [21]. Thus, because the linear thrust model reduces the number of measured variables while limiting the error introduced by the approximation, this model will be used for the rest of this thesis.…”

Section: Figure 8 Light Pressure On Solar Sailmentioning

confidence: 99%

“…One last run shows the de-orbit time assuming a perfectly reflecting solar sail, where r=s=1. The represents the sail performance with the commonly assumed reflectance values for a solar sail [21]. Table 9 shows the de-orbit time for every test case.…”

Section: Performance -Orbit Trajectoriesmentioning

confidence: 99%

See 2 more Smart Citations

Atomic Oxygen Considerations For LEO De-Orbit Trajectories Using Solar Sails

Fugett¹

View full text Add to dashboard Cite

Solar sails have the potential to benefit many future space exploration missions, but they lack the heritage required for present-day use. To grow confidence in solar sail technology, they could be deployed on LEO satellites higher than 600 km to help de-orbit the satellite within 25 years upon mission termination. To determine how atomic oxygen would affect the solar sail, material from Lightsail-2 was tested in a thermal-energy, isotropic, atomic oxygen vacuum chamber based in the space environments laboratory in California Polytechnic State University. The sail material, aluminized Mylar, was tested for its survivability on both the coated and uncoated side, as well as tested for the optical degradation of the coated side. The uncoated side was found to be completely eroded after a fluence of 2.27 x10 20 atoms/cm 2 , or ~40 days in International Space Station orbit. The coated side experienced no mass loss, but signs of significant undercutting were found with a fluence of 1.19 x10 21 atoms/cm 2 , or ~200 days at station orbit. The stitches present on the coated side, meant to prevent tear propagation, eroded before the sample experienced a fluence of 4.13 x10 20 atoms/cm 2 , or ~70 days at station orbit. The average total reflectivity of the material dropped by ~5% after atomic oxygen exposure, however no correlation with fluence was found. Average specular reflectivity remained unchanged after atomic oxygen exposure. The reflectivity results were impacted by wrinkling in the material, which was found to have a much larger impact than atomic oxygen exposure. These results were paired with an optimal de-orbit trajectory algorithm, developed in this thesis, to determine how atomic oxygen would affect a solar sail deployed to de-orbit an 800 km LEO satellite with a ballistic coefficient of 0.1. Using a simplified 2D orbit case, it was found that the satellite would de-orbit within 12-18 years, depending primarily on the solar activity level. The measured worst-case for optical degradation increased deorbit time by ~6 months. Additionally, assuming that the sail material was perfectly reflecting decreased de-orbit time by 2-4 years. The amount of fluence required to erode the uncoated Mylar, and the amount required to erode the stitches, were both reached long before the satellite re-entered. It is therefore recommended that the solar sail minimize uncoated side exposure to atomic oxygen, and a more atomic oxygen-resistant stitch material be found. The fluence required to produce significant material undercutting was reached only once the satellite's orbit had degraded to below 400 km. But the undercutting was observed to structurally compromise the material; thus, future LEO solar sail mission designers must take care when balancing added performance with higher failure risk when considering the tension in the deployed sail.

show abstract

Direct Thrust Efficiency for the L’Garde Sail Surface with a Linear Reflectivity Model

Cited by 2 publications

References 30 publications

Light radiation pressure upon an optically orthotropic surface

Light radiation pressure upon an optically orthotropic surface

Atomic Oxygen Considerations For LEO De-Orbit Trajectories Using Solar Sails

Contact Info

Product

Resources

About