Analytical Study on Condensation Heat Transfer Characteristics of Paper in Steam Heating Process

Steam heating characteristics of paper are studied analytically. One-dimensional numerical simulation model is developed by considering the conservation equations of mass, momentum and energy. The influences of suction pressure, internal steam condensation and capillary flow are considered in this model. This numerical simulation gives us temperature, moisture and pressure distributions in the direction of paper thickness. The validity of the model is confirmed by comparison of the energy absorption between simulation results and experimental results. Numerical simulation results indicate that absorbed energy rate decreases with increasing of the moisture content at the surface region in the case of low permeability paper and absorbed energy rate decreases with increasing of the condensation region in the case of high permeability paper. Dimensionless numbers are derived from the basic equations, which are related to the mass of steam flow rate in the paper and absorbed energy rate. We apply these dimensionless numbers to summarize the experimental and numerical simulation results.