There are still many factors affecting the surface temperature of the heating tube. The following is about how to estimate the surface temperature of the heating tube under static air.
Take an electric heating tube with an outer diameter of φ12mm, and use an electric heating tube made of No. 10 steel with a relatively uniform surface temperature to make the experiment. In order to ensure the accuracy of temperature measurement, nickel-aluminum thermocouples are welded on the surface of the heating tube (after other experiments proved that the temperature of the heating rod surface measured by this method is relatively correct).
The heating rod is heated in a static air medium to make the power on the surface of the heating rod from 0.1-6W / cm2, and the temperature measured on the surface of the heating rod is 70-600 degrees Celsius.
After testing, we can get that the the surface load of the heating tube is proportional to the surface temperature under a static air medium.
The detail is as follows, for reference:
Surface load Corresponds to surface temperature
1W / CM2 300 ℃
2W / CM2 400 ℃
3W / CM2 500 ℃
4W / CM2 580 ℃
5W / CM2 630 ℃
Note: The following relationship must be viewed under static air media.
Based on the data above, the power necessary for the temperature of the electric heating tube can be calculated in the static air.