Effect of the particle temperature on lift force of nanoparticle in a shear rarefied flow*

The nanoparticles suspended in a shear flow are subjected to a shear lift force, which is of great importance for the nanoparticle transport. In previous theoretical analysis on the shear lift, it is usually assumed that the particle temperature is equal to the temperature of the surrounding gas media. However, in some particular applications, the particle temperature can significantly differ from the gas temperature. In the present study, the effect of particle temperature on the shear lift of nanoparticles is investigated and the corresponding formulas of shear lift force are derived based on the gas kinetic theory. For extremely small nanoparticles (with radius R < 2 nm) or large nanoparticles (R > 20 nm), the influence of the particle temperature can be neglected. For the intermediate particle size, the relative error induced by the equal gas-particle temperature can be significant. Our findings can bring an insight into accurate evaluation of the nanoparticle transport properties.

Automated summary

This study investigates the influence of particle temperature on the shear lift of nanoparticles and derives corresponding formulas based on gas kinetic theory. The findings reveal the significant impact of particle temperature on nanoparticle transport properties, especially in cases where the gas-particle temperature equality assumption may lead to significant errors.