By adding particles into a gas flow

a gas-solid flow is formed. As the gas velocity increases

the gas-solid flow shows different patterns as bubbling fluidization

circulating fluidization and pneumatic conveying

in which the concentration of particles and the motion of gas-solid mixture are different

influencing the heat transfer between the gas-solid flow and immersed surface. In this paper

the heat transfer characters of the three flow patterns are reviewed

and the influencing factors

heat transfer mechanism and models are summarized. The concentration of particles and their movement play a decisive role on the heat transfer

and the operating parameters (gas velocity

bed pressure

bed temperature

etc) influence the heat transfer through changing the particle concentration and movement. A case of heat transfer enhancement

the heat exchange between gas-solid mixture and fixed bed

is analyzed. In addition

the future research area and the difficulty are presented.