| A large quantity of heat and moisture diffused during production in large and hot-humid industrial plants, resulted in high temperature and humidity in summer and cold wet air environment in winter. That was bad for physical health of workers, and also made the building envelopes condensed, added extra moisture to the wall and roof surfaces, increased the risk to develop microbial vegetation, and even effected the production. In this paper, taking the large and hot-humid paper-making industrial plant for object, studied on moisture condensation of large and hot-humid plant envelopes, to provide theoretical support for problem solution of envelope condensation and anti-condensation design of new plant envelopes and so on.Using Computational Fluid Dynamics method, numerically simulated the effects of multiple factors on moisture condensation of large and hot-humid plant envelopes, and the condensation behavior of envelopes under different conditions, based on investigation, measurement and orthogonal experiment. The main conclusions were:Several factors affected condensation on plant envelopes, including meteorological parameters, thermal resistance of building envelopes, thermal and humid environment of the plant, which affected by heat and moisture diffusion of the machines, volume of machinery-supplying air, temperature of supplying air, volume of machinery-exhausting air, and air organization in addition.Specific factors played different roles on inner surface moisture condensation of hot-humid paper-making plant envelopes, the order was temperature of supplying air, volume of machinery-supplying air/temperature outside the plant, ratio of production and plant volume, volume of machinery-exhausting air, thermal resistance of building envelopes, and air organization. Temperature outside the plant, volume of machinery-supplying air, temperature of supplying air had significant influence on condensation; thermal resistance of building envelope, ratio of production and plant volume, air organization, volume of machinery-exhausting air had some influence.Difference between inner surface temperature of envelope and air dew-point temperature had a linear relationship with the factors, and deduced multiple linear regression equation. The difference of temperature become bigger with the increasing of temperature outside the factory, thermal resistance of building envelope, volume of machinery-supplying air, or temperature of supplying air, and that become smaller with the increasing of ratio of production and plant volume, volume of machinery-exhausting air. |
