Features of high frequency heating

    High-frequency heating is also called "dielectric heating". Under the action of a high-frequency electromagnetic field, the material absorbs electromagnetic energy and converts it into heat inside, which is used to evaporate water. The high frequency used for drying and heating is 1~100MHz (high frequency, HF), and can also be divided into high frequency (HF, 3~30MHz) and ultra high frequency (VHF, 30~300MHz). And 300MHz~300GHz is called microwave (MV). The frequency used for heating and drying is mainly 13.56MHz, 27.12MHz, 40.68MHz (high frequency), 915MHz, 2450MHz (microwave). The main features of high frequency heating are:

    ①The heating speed becomes faster, the electromagnetic field and the material act as a whole, and the heat effect is quickly generated inside the material, and the heating process can be completed within a few seconds;

    ②The heating is uniform, and the volume heating effect leads to uniform heating, which avoids the temperature gradient that occurs in ordinary heating;

    ③The process is controlled quickly, the energy output can be realized by turning on or off the generator's power supply, the operation is convenient, and the heating intensity can be realized by controlling the power output;

    ④The selective heating electromagnetic field is only coupled with the solvent in the material and not with the substrate. Therefore, the moisture is heated and evaporated, and the carrier (substrate) of the moisture is mainly conducted to heat.

(Huiputech)