Advanced Thermal Model

The Advanced Thermal Model is a premium component that models junction-to-ambient heat transfer via conduction, convection, and radiation. It is suitable for PCB components, power semiconductors, and custom thermal packages.

Physics

The component solves a combined conduction/radiation heat balance:

Initial estimate: T_case = T_amb + P × R_ca (pure conduction)
Radiation correction loop (up to 20 iterations, converges when ΔT < 1e-6 K):
- P_rad = ε × σ × A × (T_case⁴ − T_amb⁴)
- P_conv = max(0, P − P_rad)
- T_case = T_amb + P_conv × R_ca
T_junction = T_case + P × R_jc

Where σ is the Stefan-Boltzmann constant (5.67 × 10⁻⁸ W/m²K⁴).

Ports

Port	Direction	Type	Description
`power_dissipation`	Input	Power (W)	Total power dissipated by the component
`ambient_temp`	Input	Temperature (°C)	Ambient temperature (default 25 °C)
`junction_temp`	Output	Temperature (°C)	Semiconductor junction temperature
`case_temp`	Output	Temperature (°C)	Package case temperature
`heat_flux`	Output	Power (W)	Total dissipated power

Parameters

Parameter	Default	Unit	Description
`thermal_resistance_jc`	5.0	°C/W	Junction-to-case thermal resistance
`thermal_resistance_ca`	20.0	°C/W	Case-to-ambient thermal resistance (includes heatsink)
`emissivity`	0.9	-	Surface emissivity (0 = perfect reflector, 1 = blackbody)
`surface_area_cm2`	4.0	cm²	Effective radiating surface area

Example

import hardwave
import hardwave.stdlib
import hardwave.premium

hardwave.premium.configure()  # reads HARDWAVE_ORGANIZATION_ID and HARDWAVE_SECRET_KEY from env
hardwave.premium.sync()

from hardwave.components import ComponentRegistry
from hardwave.simulation import SimulationGraph, SimulationEngine

ThermalModel = ComponentRegistry.instance().get("AdvancedThermalModel")

graph = SimulationGraph()
graph.add_component(ThermalModel("mosfet", param_values={
    "thermal_resistance_jc": 3.2,
    "thermal_resistance_ca": 15.0,
    "emissivity": 0.9,
    "surface_area_cm2": 4.0,
}))

result = SimulationEngine(graph).run(inputs={
    "mosfet": {
        "power_dissipation": 4.5,
        "ambient_temp": 35.0,
    },
})

print(f"Junction temp: {result.get_output('mosfet', 'junction_temp'):.1f} °C")
print(f"Case temp:     {result.get_output('mosfet', 'case_temp'):.1f} °C")

When to use this component

Estimating MOSFET or IGBT junction temperature under load
Comparing heatsink options by adjusting thermal_resistance_ca
Modelling radiation effects at elevated case temperatures
Coupling with power electronics components in a larger simulation graph

This component requires a Hardwave premium subscription. See Premium Components for setup instructions.

​Physics

​Ports

​Parameters

​Example

​When to use this component

Physics

Ports

Parameters

Example

When to use this component