中文摘要：

研究了负压场中相对湿度的影响因素：干湿球温度、罐体内压力及罐体内湿空气和冷凝器冷却水的温度差，并考察了负压场中木材表面的水分蒸发现象。结果表明，负压场中的相对湿度受干湿球温度及罐体内湿空气和冷凝器冷却水的温度差影响，当冷凝器中水温不变时，相对湿度随罐内温度升高而减小。罐内压力对相对湿度有较小的影响，当压力从50kPa上升到101kPa时，相对湿度从70％降低到65％。在负压场下若无外部加热将基本上不发生蒸发。图6参12。

英文摘要：

Effects of pressure and temperature in the chamber during vacuum drying on the relative humidity and evaporation of wood surface were investigated by using the vacuum chamber. The setting temperature during vacuum drying included dry-bulb temperature ta, the wet-bulb temperature tw and the temperature difference between the air in the vacuum chamber and the cooling water in the condenser. Results indicated that relative humidity during vacuum drying was affected by the dry-bulb temperature td, the wet-bulb temperature tw and the temperature difference between the air in the vacuum chamber and the water in the condenser. Relative humidity of wood decreased with the increase in temperature at the given temperature of the water in the condenser. The relative humidity was affected slightly by pressure in the vacuum chamber pA, and it decreased from 70% to 65% with pA increased from 50 kPa to 101 kPa. Moreover, there was nearly no evaporation under the vacuum without external heating.