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　　The factors affecting the drying rate of food include heat transfer rate, external diffusion rate and internal diffusion rate.

　　Increase the external diffusion rate When the drying is in the constant speed drying stage, the external diffusion resistance of the chicken powder crusher becomes the main contradiction of the whole drying rate, so reduce the external diffusion resistance and increase the external diffusion rate,. The external diffusion resistance of chicken essence drying mainly occurs in the boundary layer, so it is necessary to reduce the water vapor concentration of the medium, increase the mass transfer area, and also increase the drying speed. Increase the medium flow rate, reduce the thickness of the boundary layer, and improve the convective heat transfer coefficient. The chicken essence dryer can also improve the convective mass transfer coefficient, which is beneficial to improve the drying speed.

　　Increase the internal diffusion rate of water. The internal diffusion rate of moisture in chicken essence drying equipment is affected by both wet diffusion and thermal diffusion. Moisture diffusion is the movement of water in materials due to humidity gradient, and thermal diffusion is the movement of water due to temperature gradient in physics. To increase the internal diffusion rate, when the direction of thermal diffusion is consistent with that of wet diffusion, heat transfer should be strengthened and the temperature gradient in the material should be increased. When the two are opposite, strengthening the temperature gradient can increase the resistance of thermal diffusion, but it can enhance heat transfer. When the material temperature is increased, the wet diffusion can be increased, so it can speed up drying; Make the direction of thermal diffusion consistent with that of wet diffusion, that is, try to make the central temperature of the material higher than the surface temperature, such as far infrared heating and microwave heating; Reducing the total pressure of the medium can increase the wet diffusion coefficient, thus increasing the wet diffusion rate; The drying rate of chicken essence equipment is affected by other factors such as body properties and shape.