⚖️ Spacecraft Heat Balance Calculator

Single-node radiative equilibrium · hot & cold bounding cases · α/ε and area effects

Ad placeholder

Geometry & Surfaces

Cases

Hot Case

Absorbed solar
– W
Absorbed albedo
– W
Absorbed Earth IR
– W
Total heat in
– W
Equilibrium temperature
– °C
–

Cold Case

Absorbed solar
– W
Absorbed albedo
– W
Absorbed Earth IR
– W
Total heat in
– W
Equilibrium temperature
– °C
–
Ad placeholder

📖 How to use

  1. Enter the three areas (sun-projected, nadir-facing, total radiating) and the area-averaged α/ε — get coating values from the Reference page.输入三个面积（对日投影、对地、总辐射）与面积加权的 α/ε——涂层数值见参考页。
  2. Set internal dissipation for max-ops (hot) and safe-mode/eclipse (cold); the two cases bound the mission.分别设置最大工况（热）与安全模式/地影（冷）的内部耗散；两个工况即任务包络。
  3. Compare the equilibrium temperatures with your component limits: the verdict boxes flag outside −20…+50 °C (typical electronics).将平衡温度与设备温度范围对比：结论框按 −20…+50 °C（典型电子设备）给出提示。
  4. Hot too hot → lower α/ε or add a radiator; cold too cold → add MLI (smaller radiating area) and heaters — size them in the dedicated tools.过热 → 降低 α/ε 或加散热面；过冷 → 加多层隔热（减小辐射面积）并配加热器——用对应工具细化。

Single-node heat balance

Treating the spacecraft as one isothermal node, equilibrium requires heat in = heat out:

α·S·A_sun + α·a·S·F·A_nadir + ε·E·F·A_nadir + Q_int = ε·σ·A_rad·T⁴

so T = [(Q_absorbed + Q_int)/(ε·σ·A_rad)]^0.25. The α/ε ratio sets the sun-driven temperature: white paint (α/ε ≈ 0.2) runs cold, black paint (≈ 1.1) neutral, bare metal (≈ 3) hot.

A single node hides internal gradients (real spacecraft see ±10–20 °C spread) — use it to bound the design and to size radiators/heaters, then verify with a multi-node model (e.g. Thermal Desktop/ESATAN).

All computation runs locally in your browser.

单节点热平衡

把整星视为一个等温节点，平衡条件为吸热 = 散热：

α·S·A_sun + α·a·S·F·A_nadir + ε·E·F·A_nadir + Q_int = ε·σ·A_rad·T⁴

即 T = [(Q_吸收 + Q_内)/(ε·σ·A_rad)]^0.25。α/ε 之比决定受晒温度：白漆（α/ε ≈ 0.2）偏冷，黑漆（≈ 1.1）居中，裸金属（≈ 3）偏热。

单节点掩盖了内部梯度（真实卫星各处相差 ±10–20 °C）——它用于包络设计与散热面/加热器初步定容，之后应以多节点模型（Thermal Desktop/ESATAN 等）校核。

全部计算在你的浏览器本地完成。