Forced convection heat and mass transfer at small Péclet numbers from a particle of arbitrary shape

Abstract

At small Péclet numbers the average Nusselt number for steady-state forced convection heat transfer from an isothermal particle of arbitrary shape to an external fluid of infinite extent flowing in laminar flow may be expressed in the form ▪ where Nu 0 is the Nusselt number for heat transfer to a stagnant fluid. This relation is shown to hold independently of the Reynolds number. Moreover, it applies equally well to both solid and fluid particles. Higher-order terms in the expansion depend upon the particle Reynolds number and the orientation of the particle relative to the free-stream velocity. An explicit calculation of the next term in the above expansion is presented for the case of low Reynolds number (Stokes) flow relative to a solid or fluid particle of arbitrary shape. The analysis also solves the analogous mass-transfer problem.