AN IMPROVED ANALYSIS OF THE THERMOPHORETIC FORCE ON A SMALL PARTICLE SUSPENDED IN A RAREFIED PLASMA

In Brock's (1964) analysis concerning the thermophoretic force on a sm all particle suspended in a rarefied plasma with a temperature gradien t, the effect of the presence of an external magnetic field on the ion and electron components of the thermophoretic force was demonstrated. However, the panicle suspended in the plasma was assumed to be electr ically neutral, which is obviously not realistic. Consequently, Brock obtained similar expressions for the thermophoretic force components d ue to, respectively, atoms, ions and electrons for the case without th e external magnetic field. The present paper improves Brock's analysis by taking the charging of the suspended particle into account and obt ains somewhat different expressions from his results for the thermopho retic force components due to ions and electrons.