Three external factors affecting the drying speed of wood drying equipment

Three external factors affecting the drying speed of wood drying equipment

1. Temperature

Temperature is the main factor affecting the drying speed of wood. As the temperature rises, the water pressure in the wood increases, and the viscosity of liquid free water decreases, which is beneficial for promoting the flow and diffusion of water in the wood; The moisture solubility of copper wire drying medium is improved, which accelerates the evaporation rate of surface moisture on wood. However, it is worth noting that if the temperature is too high, it can cause cracking and deformation of the wood, reduce mechanical strength, discoloration, etc., which should be appropriately controlled.

2. Humidity

Relative humidity is an important factor affecting the drying speed of wood. At the same temperature and airflow velocity, the higher the relative humidity, the greater the partial pressure of water vapor in the medium, and the less likely the moisture on the surface of the wood is to evaporate into the medium, resulting in a slower drying speed; When the relative humidity is low, the surface moisture evaporates quickly, the surface moisture content decreases, the moisture gradient increases, the diffusion of moisture increases, and the drying speed is fast. However, if the relative humidity is too low, it can cause the occurrence or even aggravation of drying defects such as cracking and honeycomb.

3. Airflow circulation speed

The air circulation speed is another factor that affects the drying speed of wood. High speed airflow can destroy the saturated vapor boundary layer on the surface of wood, thereby improving the heat and mass transfer conditions between the medium and the wood, and accelerating the drying speed. For difficult to dry wood or when the moisture content of wood is low, the movement of moisture inside the wood determines the drying speed; Increasing the flow rate of the medium to accelerate the evaporation rate of surface moisture has no practical significance. Instead, it will increase the gradient of moisture content and increase the risk of drying defects. So, difficult to dry materials do not require a high medium circulation speed.