this paper deals with optimal operation of a three-product dividing-wall column (dwc). the main idea is to design a control structure, through a systematic procedure for plantwide control, with an objective to achieve desired product purities with the minimum use of energy. exact local method is used to find the best controlled variables as single measurement or combination of measurements base...

[1] We conducted two laboratory experiments at the meter scale in which water was applied to the top of an initially dry, uncemented wall composed of porous bricks. One experiment (Experiment 1) encouraged evaporation and resulting mineral precipitation, while the other (Experiment 2) was designed to minimize these processes. In both cases, processes acting within the fracture network controlle...

We present a dynamic van der Waals theory. It is useful to study phase separation when the temperature varies in space. We show that, if heat flow is applied to liquid suspending a gas droplet at zero gravity, a convective flow occurs such that the temperature gradient within the droplet nearly vanishes. As the heat flux is increased, the droplet becomes attached to the heated wall that is wett...

Based on an extended model of Marangoni convection during absorption accompanied by chemical reaction certain characteristics of the process are studied. Thus, the probability of oscillatory modes occurring in the system is analysed, the dimensions of the convective cells are evaluated and the gas-liquid contact time necessary for the instability to appear is determined. The quantitative conclu...