Transport Phenomena Occurred In Counter-Current Gas-Liquid Falling Film Flow

Transport phenomena of falling film flow can be found in many fields of process industry. It is of great importance to investigate the flow patterns and mass transfer efficiency for the design of new type of mass transfer or chemical reaction equipment.The background of falling film being applied in process industry and recently published research works, including theoretical prediction and experimental research, is introduced. Reports on Double-Side falling film, falling film under turbulent condition, and coupling mass transfer with heat transfer are also introduced.Experimental test and computational simulation were used to investigate the mass transfer efficiency for a Double-Side falling film flow. Experimental rig for testing the mass transfer efficiency of falling film flow was designed and the concentration change of the liquid phase under different operating conditions, such as flow rate of gas and liquid, were measured. Models for simulating mass transfer of the falling film flow were developed to predict the profiles of velocity and concentration in gas and liquid phase. The simulated results fit well with experimental data.Theoretical model for simulating the desorption process of iso-propanol solution into nitrogen was proposed. In the model simultaneous transport phenomena of momentum, heat and mass transfer processes was considered. Experimental work was carried out to verify the proposed model. It was found that the simulated results were in good agreement with the experimental data in some cases. The influence of gas and liquid inlet velocities on mass transfer efficiency was predicted by the proposed model. By modifying the model mentioned above, a mass-transfer CFD model was proposed to simulate the coupling effect between heat and mass transfer processes. It was found that heat and mass transfer can be simulated more accurately by the new model than by the traditional one.