An Air Heater Is An Electric Heating Device That Mainly Heats A Gas Stream

An air heater is an electric heating device that primarily heats a gas stream. The heating element of the air heater is a stainless steel electric heating tube, and the heater inner cavity is provided with a plurality of baffles (baffles) to guide the gas flow direction, prolong the residence time of the gas in the inner cavity, thereby fully heating the gas to make the gas Uniform heating to improve heat exchange efficiency. The heating element of the air heater is a stainless steel heating tube which is filled with a heating wire in a seamless steel pipe, and the gap portion is filled with a magnesium oxide powder shrink tube having good thermal conductivity and insulation. When the current passes through the high temperature resistance wire, the generated heat is diffused to the surface of the heating tube by the crystalline magnesium oxide powder, and then transferred to the heated air to achieve the purpose of heating.

Air heater influence factor

1. Increasing the gas inlet flow rate of the air heater can enhance the convective heat transfer of the air electric heater, and reduce the surface temperature of the electric heating element in the air heater, which not only helps to prolong the service life of the air heater electric heating element, but also makes the air The heat loss of the electric heater is reduced, and the efficiency of the air heat exchanger is improved, but if the speed is too large, the pressure loss is sharply increased, which is disadvantageous for the improvement of the heating efficiency.

2. If the other conditions are the same and the surface load is changed, the wall temperature of the electric heating element in the air heater will change linearly. If the surface load increases, the wall temperature of the electric heating element will increase, which will reduce the electric heating element in the air heater. The service life, but if the surface load is too small, the wall temperature is too low, and the efficiency of the air heater heat exchanger is lowered, so the selection of the surface load of the electric heating element in the air heater is important.

3. When the air temperature T2 is increased in the air heater, the gas Reynolds number is reduced due to the increase of air viscosity, so that the convective heat transfer intensity is lowered, and the surface temperature of the electric heating element in the air heater is simultaneously raised, and the infrared carbon sulfur analyzer makes the heat dissipation. The loss is increased, thereby reducing the efficiency of the heat exchanger. When the T2 is increased too much, the temperature of the surface of the electric heating element is also greatly increased, so that the general electric heating element cannot be withstood, so the increase of T2 is usually limited by the heat resistance of the electric heating element material in the air heater.