Electric heating film is a translucent polyester film that can generate heat when energized. It is made by printing and hot-pressing conductive special ink and metal current-carrying strips or infrared radiation paint between two layers of insulating polyester film (PET). become.

Graphene electric heating film preparation process

The base material is graphene composite material + pet + copper + silver paste + copper wire.

Graphene slurry + front-side coating process is currently the most advanced conductive film preparation technology.

The process is not only suitable for the production of graphene floor heating film, the original film can also be used to prepare heating wall panels, floors, heating paintings and other products.

Water-soluble materials combined with coating technology have good uniformity, computer numerical control, precise thickness and stable power.

When the power is turned on, the graphene electric heating film mainly emits heat in the form of far-infrared radiation. Compared with the traditional radiator heating method, the graphene electric heating film heating system not only has good heating effect and saves energy, but also increases the user's usage area, reduces the amount of maintenance, and solves the heavy pollution, difficult measurement, and Problems such as difficulty in charging fees. Now we will introduce its energy-saving mechanism from the following aspects.

Heat dissipation method of electric heating film

Theoretically, there are three basic ways of heat transfer: heat conduction, heat convection and heat radiation. Technically speaking, these three methods generally cannot be completely separated. Heat transfer is a comprehensive process. If a certain heating method is dominant, it is called heating by this heat transfer method.

According to the national standard GB8623-88, products with an infrared radiation conversion efficiency >50%, that is, more than half of the energy transferred by infrared radiation, and the sum of energy transferred by conduction and convection <50%, can be called far-infrared radiation products. The electrothermal radiation conversion efficiency of ordinary electric heating films is generally <70%.

In electric heating film heating based on thermal radiation, the expression of the heat emitted by the electric heating film is:

(In the formula: Q is the heat of the electric heating film, E is the emissivity of the electric heating film, Rb is the blackbody radiation constant, T1 is the operating temperature of the electric heating film, and T2 is the surrounding environment temperature.)

In radiant heating, the heat is proportional to the fourth power of the emitter temperature, while in convection heating this ratio is lower, that is, the temperature of the heating element has a greater impact on radiant heating. Furthermore, the emissivity E of the infrared radiation electric heating film is very high. , generally around 0.9, indicating that the energy conversion rate in radiant heating is relatively high.

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The propagation process of far-infrared electric heating film radiation energy

Radiant heating consumes less energy in the air, has high energy utilization rate and good heating effect. This is essentially different from the propagation of convection energy:

Convection heating relies on an intermediate medium (air). The air molecules close to the hot radiator surface absorb heat, increase the temperature, increase the movement, and flow to the upper part of the space under the action of buoyancy force, thus driving the cold air to flow to the radiator.

The hot and cold air flows back and forth in this way, so that the air temperature in the active area of the room finally reaches the requirements. The characteristics of hot and cold air flow determine that the air temperature in the upper part of the room is always higher than the temperature of the activity area where people are located, which increases the waste of energy, resulting in relatively low energy utilization rate and poor heating effect in convection heating.

The spread of radiant energy does not depend on the air medium, but directly interacts with the human body. Moreover, the main components of air, O2 and N2, almost do not absorb infrared band energy. The air can only receive some energy when it is in direct contact with the heat source and the heated body (human body).

For example, when we stand outdoors in winter, once the sun shines on our bodies, our bodies will still feel warm even though the outdoor temperature has not changed significantly.

The human body’s heat gain mechanism

Different heating methods have different ways in which the human body and surrounding objects obtain energy.

The infrared radiation generated when the electric heating film is working is part of the electromagnetic wave. When the radiation energy is projected onto the human body, most of it is absorbed by the surface of the human body, and only a small part of the radiation is transmitted into the interior of the human body and then absorbed. The greater the absorption ratio of the human body, that is, the greater the absorption rate, the higher the energy utilization rate.

In convection heating, they mainly obtain energy from the heated air through convection, so the air temperature in the room is always higher than the temperature of the surrounding objects. In radiant heating, energy is mainly obtained directly from the radiation source through radiation. The indoor air temperature is always lower than the temperature of the surrounding objects, which is why radiant heating saves energy. Experiments have proven that: a room temperature of 16°C under radiant heat conditions is equivalent to a convection environment of 18~20°C.