Heat flux sensor working principle

What is soil heat flux sensor?

Soil heat flux sensor, also known as, soil heat flux plate, heat flux plate, heat flow meter, soil heat flux sensor is a traditional soil thermal performance tester, mainly used to measure the energy balance of the soil and the heat conduction rate of the soil layer, its value depends on the temperature gradient between the upper and lower soil layers and the thermal conductivity of the soil, the value of heat flux inside the object being measured are relatively small.

Soil heat flux sensor using thermopile to measure the temperature gradient, the thermopile has two different metal materials to form a thermopile detector to receive thermal radiation, thermal radiation can make the two do not use the material of the junction between the temperature difference between the potential to output in the form of voltage, voltage is proportional to the heat flux.

How does  soil heat flux sensors work :

Soil heat flux sensors, also known as heat flux panels, soil heat flux panels, heat flux meters, and other names, are instruments used to measure heat fluxes and can be used for internal soil measurements.

Soil heat flux is one of the most important parameters in agrometeorological research as it allows one to study the energy stored in the soil as a function of time.

The output radiation of a heat flux sensor is W/m2 and the heat flux is calculated by the formula

Heat flux (w/m2) = coefficient (w*m-2/mv) * output (mv).

Throughout the year, the soil heat flux varies with the seasons. In summer, the soil heat flux is positive, i.e., heat enters the soil layer, and the value is large. In winter the soil heat flux is negative, i.e. heat is released from the soil to the atmosphere, but in smaller amounts.