Incipient rolling, sliding and suspension of particles in horizontal and inclined turbulent flow

Optimization of Flow Direction to Minimize Particulate Fouling of Heat Exchangers

“…Based on the flow conditions, i.e., main stream velocity of 1.25 m/s and air temperature 25 • C, the Reynolds number of the flow for the tubes of the heat exchanger is equal to 3.2 × 10 4 , which corresponds to a separation angle of 80 • from the stagnation point according to Sons and Hanratty [30]. Due to separation of the flow at the top of the heat exchanger tube, both the removal of particles by shear flow decreases as found by Cabrejos and Klinzing [32] and Halow [33], and the speed of the particles decreases. Both effects increase the deposition rate of particles at the top of the heat exchanger tube.…”

Impact of continuous particle size distribution width and particle sphericity on minimum pickup velocity in gas–solid pneumatic conveying

“…The focus of this work is on the minimum pickup velocity (U pu ), which is defined as the gas velocity required to initiate the rolling motion of (Hallow, 1973) or suspend (Kalman et al, 2005) the particle initially at rest on a surface. U pu has been relatively less studied but is an important parameter in the operation of such systems.…”

Removal of gas-side particulate fouling layers by foreign particles as a function of flow direction

“…the tubes of the heat exchanger is equal to 3.2×10 4 , which corresponds to a separation angle 14 of 80º from the stagnation point according to Sons and Hanratty [36]. Due to separation of the flow at the top of the heat exchanger tube, both the removal of particles by shear flow decreases [38,39] and the speed of the particles decreases. Both effects increase the deposition rate of particles at the top of the heat exchanger tube.…”