Table of Contents ECSS Model Page
Background Information Atmosphere and ionosphere
Orbital version

Overview

This implementation of the atmosphere and ionosphere models runs in combination with the orbit generator. SPENVIS verifies if a spacecraft trajectory has been generated prior to accessing the model page. If not, an error message is displayed with a link to the orbit generator. Please note that running the orbit generator will delete all existing output resulting from models that use the spacecraft trajectory.

SPENVIS calculates the density of one particle type at each orbital point. In addition, the flux of this particle type on an oriented plate is determined, as well as the orbital fluence and total mission fluence. For atomic oxygen, a material erosion factor can be applied to estimate material loss due to oxydation.

The input parameters and options for the models are described below. When the input form has been completed, pressing the button will start the calculation and bring up the "Results" page.

Model parameters

Selection of atmosphere/ionosphere model and constituent

In contrast with the positional version, the orbital version of the atmosphere/ionosphere models requires the selection of one constituent. The atmosphere/ionosphere constituents and model input parameters depend on the selected model. The HWM93 model is used to calculate wind speeds.

Erosion yield for atomic oxygen

When the atmospheric constituent atomic oxygen is selected, material erosion depths are evaluated. The erosion yield can be selected from a list of experimentally determined yields or a value can be entered directly.

Orientation of the exposed surface

SPENVIS calculates fluxes and fluences of particles on an oriented surface. The orientation of the exposed surface is defined in the reference frame attached to the satellite. The reference frame is defined when the spacecraft orbit is generated.

The direction of the normal of the exposed surface can be defined as being parallel to the polar axis of the satellite reference frame, or the spherical coordinates of the surface normal can be specified.

Thermal motion

The contribution of thermal motion to the fluxes can be included or neglected.

Results

The atmosphere and ionosphere models produce the files listed in the table below. A description of the file formats can be brought up by clicking on their description in the table.

The report file spenvis_atp.html contains the input parameters and summary tables. The spenvis_ato.txt file contains densities, fluxes, fluences and other parameters for each orbital point.

Output files generated by the atmosphere and ionosphere models
File name Description
spenvis_atp.html Report file
spenvis_ato.txt Densities, fluxes and fluences for each orbital point

To generate plots, select the plot type(s), options and graphics format, and click the or button. The current page will be updated with the newly generated plot files.

Last update: Mon, 12 Mar 2018