Microparticle suspensions are prevalent in both natural
and industrial
environments, playing a crucial role in various processes. The heat
transfer characteristics between particles and fluids are critical
to many of these processes. This study employs the Arbitrary Lagrangian-Eulerian
finite element method to simulate and analyze the particle dynamics
and fluid–solid heat transfer characteristics within a microchannel,
aiming to determine fluid–solid heat transfer characteristics
based on the average temperature of particles. The effects of five
factors (particle thermal conductivity, specific heat capacity, fluid
Reynolds number, particle diameter, and initial particle position)
were comparatively analyzed. The results indicate that particles in
a laminar microchannel reach a self-equilibrium position under the
combined action of fluid shear gradient and wall lift force, with
particle size being the primary influencing factor. The shear effect
of the fluid causes the particle to rotate, thereby enhancing the
convective heat transfer between the particle and the fluid. The Reynolds
number also significantly impacts this process. Additionally, thermal
conductivity, specific heat, particle size, and position can influence
the fluid–solid heat transfer characteristics by altering the
internal temperature distribution of the particle. We derived an expression
for the Nusselt number using a dimensionless analysis method, which
describes the heat transfer between the particle and fluid based on
the average temperature of the microparticle.