Radiation Panel

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Description

The Radiation Panel represents a surface that can absorb radiation from Radiation Source components in the simulation. The panel tracks flux exposure, calculates shielding attenuation, and provides data for Total Ionizing Dose (TID) and Single Event Effect (SEE) probability calculations. Panels are typically registered with a Radiation Model to aggregate exposure across multiple surfaces.

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Example Use Cases

• Surface Radiation Exposure: Model radiation absorption on specific spacecraft faces.
• Shielding Analysis: Evaluate the effectiveness of different shielding materials and thicknesses.
• Component Protection: Determine radiation exposure levels behind shielded panels.

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Module Implementation

The radiation panel computes flux exposure based on its orientation relative to radiation sources and applies shielding attenuation.

Projected Area

The effective area exposed to a radiation source is computed from the panel area and incidence angle:

$$A_{\text{proj}}=A\cdot \max (\hat{s}\cdot \hat{n},0)$$

where $A$ is the panel area, $\hat{s}$ is the unit vector toward the radiation source, and $\hat{n}$ is the panel normal.

Shielding Attenuation

The flux transmitted through shielding material follows exponential attenuation:

$${\Phi }_{\text{shielded}}=\Phi \cdot e^{-\mu t}$$

where $\Phi$ is the incident flux, $\mu$ is the linear attenuation coefficient, and $t$ is the shielding thickness.

Ionizing Dose Increment

The increase in ionizing dose over a time step is calculated as:

$$\Delta D=\frac{{\Phi }_{\text{shielded}}\cdot A_{\text{proj}}\cdot \Delta t}{\rho \cdot t}\cdot \eta$$

where $\rho$ is the shielding density, $t$ is the shielding thickness, $\Delta t$ is the time step, and $\eta$ is the energy-to-dose conversion efficiency.

Single Event Effect Probability

The probability of an SEE occurring is modeled using Poisson statistics:

$$P_{\text{SEE}}=1-e^{-\lambda }$$

where the event rate $\lambda$ is:

$$\lambda =A_{\text{proj}}\cdot \frac{{\Phi }_{\text{shielded}}}{E_p}\cdot \Delta t$$

and $E_p$ is the average particle energy.

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Assumptions/Limitations

• The panel is modeled as a flat surface with uniform shielding properties.
• If shielding thickness or density is zero or negative, shielding effects are ignored.
• The shadow factor for non-celestial shadowing must be set manually.