The Study Of The Formation And Heat Transfer Of The Rising Liquid Film On The Surface Of A Horizontal Metallic Mesh Tube

The objective of this study is to investigate the formation of the rising liquid film on the surface of a horizontal metallic mesh tube and its characteristics.The formation of the rising liquid film could be considered as low Reynolds number flow of single-phase fluid and its mathematical model is established using Navier-Stokes equation. The distribution of the velocity under the evaporation of the liquid film is achieved numerically and the factors that influence the characteristics of the rising liquid film have been analyzed. Besides, the experiment is also done to see the flow state of the rising liquid film. In the experiment, the microscope has been used to observe the formation and flow state of the rising liquid film on the surface of a horizontal metallic tube. The average velocity of the rising liquid film is got by using the tracking method. The temperature field of the steady and unsteady process of the rising liquid film is achieved by the infrared thermal imager and the influence of the thermo-capillary flow has been analyzed. Establish heat transfer equipment of rising liquid film on the surface of a horizontal metallic tube and the circumferential temperature of the surface is measured by 0.5mm armored thermocouple laid using laser scanning technology to achieve the distribution of the heat transfer. On this basis, a combustion train utilizing the rising liquid film is invented and its auxiliary program is developed.The numerical and experimental results show that the continuous and even rising liquid film can form by using a horizontal metallic mesh tube, which is influenced by micro capillary pressure, wetting force, circumferential temperature difference, bubbles, and other factors combined. The velocity of the rising liquid film is also influenced by the size of the tube and the gap between them. The horizontal metallic mesh tube could strengthen the heat and mass transfer, which has something to do with the heat flux and the mesh. The study has a key role on the design of micro and super-micro combustor.