The core principle of the Naichi heat flux thermal conductivity analyzer is based on Fourier's law of thermal conductivity, which states that the rate of heat transfer in a solid is proportional to the temperature gradient and is related to the thermal conductivity of the material. During the specific operation, the instrument will apply a constant heat flow on one side of the tested sample, and then accurately measure the temperature change on the other side.

During this process, high-precision temperature sensors are responsible for real-time monitoring of the temperature difference on both sides of the sample, while the data acquisition system carefully records and analyzes this data in depth. According to Fourier's law of heat conduction, the thermal conductivity of the sample is calculated using a specific algorithm. The use of dual heat flux sensors and accurate temperature control technology on the flat plate can effectively reduce errors and achieve fast and stable measurement results.

The measurement steps of the Naichi heat flow method thermal conductivity analyzer are as follows:

1. Equipment preparation: Before starting the operation, organize all the accessories and instruments of the thermal analyzer to ensure that all operation options are set correctly.

2. Sample placement: Place the sample between two heating plates. For compressible samples, it is necessary to set the desired thickness value; If it is an incompressible sample, use its actual thickness.

3. Temperature setting and adjustment: After turning on the power, set the program and configure the constant temperature heating rate and sample testing mode according to the options. Adjust the output power within the temperature control zone to determine the heating rate, and determine the temperature range according to the requirements of the sample. The temperature of the two heating plates will be automatically adjusted to achieve the user-defined average sample temperature (i.e. the average temperature of the upper and lower plates) and temperature difference value.

4. Measuring heat flux: Two calibrated heat flux sensors will measure the heat flux (Q) passing through the sample, and these sensors can cover most of the upper and lower surfaces of the sample.

5. Data collection and analysis: The instrument has full automation functions, covering temperature control, data collection and analysis, which can ensure high repeatability of test results. The system will record and process the measured heat flow data, and then calculate the relevant parameters such as the thermal conductivity of the material.