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To understand the influences of nanoparticleson dewetting in ultra-thin films,both linear stability theory and numerical simulations are performed in the presentstudy,with the consideration of oscillatory structural(OS)forces.Long scale approximation is utilized to simplify thehydrodynamic and diffusion equations to a nonlinear systemfor film thickness and nanoparticle concentration.Resultsshow that the presence of nanoparticles generally suppressesthe dewetting process.Two physical mechanisms responsible for this phenomenon are addressed in the present study.When the oscillatory structural forces are relatively smaller,the essential feature of film evolution is similar to the case ofparticle-free flow.The reduction of the linear growth rate andthe postponement of film rupturing can be attributed to theincrement of the viscosity due to the presence of nanoparticles.On the other hand,when the intensity of the OS forcesbecomes stronger,the stepwise thinning of film can be observed which prevents the film from rupture.Numerical simulations indicate that this phenomenon is caused by the existence of a stable zone due to the oscillatory nature of thestructural forces.Another interesting finding is that the nonuniformity of the distribution of nanoparticle concentrationmight destabilize a spinodally stable film,and trigger the occurrence of film dewetting.
To understand the influences of nanoparticles on dewetting in ultra-thin films, both linear stability theory and numerical simulations are performed in the present study, with the consideration of oscillatory structural (OS) forces. Long scale approximation is utilized to simplify the hydrodynamic and diffusion equations to a nonlinear system for film thickness and nanoparticle concentration. Resultsshow that the presence of nanoparticles generally suppressesthe dewetting process.Two physical mechanisms responsible for this phenomenon are addressed in the present study. Who are the oscillatory structural forces are relatively smaller, the essential feature of film evolution is similar to the case of reduction of the linear growth rate and the postponement of film rupturing can be attributed to the increment of the viscosity due to the presence of nanoparticles. On the other hand, when the intensity of the OS forcesbecomes stronger, the stepwise thinning of film can be observed which prevents the film from rupture. Numerical simulations indicate that this phenomenon is caused by the existence of a stable zone due to the oscillatory nature of the structural forces. An interesting finding is that of nonuniformity of the distribution of nanoparticle concentration capable destabilize a spinodally stable film, and trigger the occurrence of film dewetting.