Study On The Flow Characteristics Of Heated Wavy Film On Uneven Substrate

As a simple open flow at low speed, liquid film flow contains various dynamicsbehaviors, and the external influences of its flow environment is extremely complicatedin practical engineering. Coupled with the effect of gravity and shear stress, the internalflow progress is quite complex. Therefore, it is not only of great significance forenriching and developing heat and mass transfer theory in the field of advancedtechnology and practical engineering, but also of vital importance to expand the contentof liquid membrane dynamics and instruct the practical application of liquid film, tostudy the characteristics of liquid film flow on uneven heated substrate.This paper mainly studies the evolution characteristics and linear stability of thenonlinear surface wave of a two dimensional viscous liquid film along an unevennon-uniformly heated wall. The major research contents can be stated as follows:1) Theoretical studies of flow stability for non-uniformly heated liquid film along anuneven substrate under the condition of adiabatic gas-liquid interface are conducted.Taken uneven substrate and heating into account, the control equations and boundaryconditions of liquid film flow on uneven non-uniformly heated wall are established fromthe continuity equation, Navier-Stokes equations and energy equation. A long waveperturbation method is used to solve the control equation for obtaining the evolutionequation of the nonlinear surface wave. Based on the obtained evolution equation,stability character of liquid film flow along sinusoidal corrugated substrate is studied.2) Theoretical studies of evolution characteristics for film surface wave on ahorizontal uneven non-uniformly wall are conducted when convective heat-transfer existat gas-liquid interface. This paper is focused on the flow characteristics of heated liquidfilm along a horizontal uneven wall. A long wave perturbation method is used to derivethe evolution equation of liquid film thickness, and obtain the numerical solution of thisevolution equation by the PDECOL code. Based on the numerical solution, evolutioncharacteristics of film surface wave and the temperature distribution of film that flow onsinusoidal corrugated substrate are researched.