Heat flux sensor: the explanation
This short review gives the reader a global heat flux sensor explanation from the original equation to how to measure it.
A heat flux sensor is a Seebeck sensor
- Heat Flux Sensors are based on the Seebeck effect.
- When heat passes through the sensor, the sensor generates a voltage signal. This voltage signal is proportional to the heat passing through the sensor such as: HF ∝ V where HF = Heat Flux, in W/m² and, V = Voltage, in V.
- gSKIN® Heat Flux Sensors can resolve heat fluxes < 0.01 W/m2.
How does a heat flux sensor work?
The gSKIN® Heat Flux Sensors is a highly sensitive Seebeck Sensor.
The sensitivity of a Seebeck Sensor depends on the thermocouple material quality used in the sensor and the number of thermocouples used.
A thermocouple consists of two separate thermopiles (n-type and p-type). These thermopiles are highly integrated in the sensor substrate, which leads to high sensitivity sensor modules.
How to measure heat flux?
All Heat Flux Sensors generate a voltage signal which is proportional to the heat that passes through the sensor element such as HF = V / S where HF = Heat Flux, in W/m2 V = Voltage, in µV and S = Sensor sensitivity, in µV/(W/m2).
In most applications, this voltage signal is in the µV range. The voltage signal is converted into the heat flux value by dividing it by the sensor sensitivity.
As the Heat Flux Sensor voltage signal is in the µV range, it is crucial to have a voltage logging unit with high voltage resolution. For R&D applications, we recommend one of the following datalogging solutions:
- gSKIN DLOG dataloggers
- Pico Technology High-Resolution Data Acquisition
- Keithly Volt Meters
If gSKIN® Heat Flux Sensor Components are to be integrated, it is recommended to design specific read-out electronics.