Heat transfer from a cylinder in axial turbulent flows

Process Parameter Settings and Their Effect on Residual Stresses in WC/W2C Reinforced Iron-Based Arc Sprayed Coatings

“…Pyrometric measurements show a slightly higher particle temperature at the point of impact on the substrate using 0.4 MPa (utilizing 220 A, 30 V), which is approximately 2080 ± 18 • C (with v particle = 86 ± 3 m/s), whereas at a PGP of 0.8 MPa (utilizing 220 A, 30 V) the particle temperature is approximately 1965 ± 25 • C (with v particle = 140 ± 7 m/s). At higher relative velocities between the continuous phase (gas phase) and dispersed phase (particle phase), the convective heat transfer of spray particles increases as the heat transfer coefficient increases with an increase of the gas velocity [81][82][83]. The heat transfer coefficient significantly depends on the type of flow as well.…”

“…The heat transfer coefficient significantly depends on the type of flow as well. In the case of a laminar flow, the heat transfer coefficient is low, whereas in a turbulent flow the coefficient is higher [81,82]. Depending on the spray nozzle design, the flow characteristics across the spray plume may differ at different PGPs used within this study.…”

An approximate estimation of velocity profiles and turbulence factor models for air-flows along the exterior of TEFC induction motors

“…Therefore, once the amounts of heat dissipated through the two end-shields are known, the energy balance equation can be solved without a number of empirical correlations. In the case of the first algorithm, for instance, correlations for forced convection from the flat and cylindrical outer surfaces of the non-drive end-shield [26][27][28] are not included in the iterative loop (in the 2 nd set of statements). After the exit from the iterative loop, these correlations [26][27][28] are used for the calculation of the turbulence factors K 2F and K 2C corresponding to the flat and cylindrical outer surfaces of the non-drive end-shield, respectively.…”

“…-The turbulence factor model (10) is derived from the model (9) by substitution of the calculated value of the coefficient K 2 = 1.6776 by the arithmetic mean of the two bounds of the range 1.7-1.9, which is reported in [2]. The model (9) is derived by using the correlations for turbulent forced convection from a cylinder in axial air-flows, which correspond to the degree of air-flow turbulence ξ = 0.1% [26][27][28]. Therefore, if the degree of air- flow turbulence is equal to zero (ξ = 0%), the model (10) can be used instead of (9) for the cylindrical outer surfaces of the end-shields, but in combination with the appropriate correlations for laminar forced convection.…”

Novel approach to analytical modelling of steady-state heat transfer from the exterior of TEFC induction motors

“…The Reynolds number is based on the angular velocity of the rotor Ω [rads -1 ]. *b Correlations from [21] are modified by introducing the Prandtl number to the 1/3 power. This is in accordance with the forms of appropriate correlations reported in [22,23].…”