Maintenance free gas bearing helium blower for nuclear plant

Molyneaux, Alex K.; Harris, M.R.; Sharkh, Suleiman M.; Hill, Steven; Graaff, T de

doi:10.1088/1757-899x/232/1/012063

Cited by 1 publication

(6 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1982; Molyneaux et al. 2017). It is of interest to keep a common density ratio but to change the spheroid size to realize different Stokes numbers in fully resolved simulations in future work, in which the effect of fluid inertia and the particle-size effect can be explored.…”

Section: Discussionmentioning

confidence: 99%

“…These large particle-to-fluid density ratios in group B can be found in some realistic applications, such as the nuclear (Molyneaux et al. 2017) and lithography (Hyman et al. 1982) industries, where helium is one of the important protected gases.…”

Section: Methodsmentioning

confidence: 96%

“…In group B, the particles have very large particle-to-fluid density ratio with λ = 50 and λ = 0.02 at St = 30 as well as for all aspect ratios at St = 100, as depicted in table 2. These large particle-to-fluid density ratios in group B can be found in some realistic applications, such as the nuclear (Molyneaux et al 2017) and lithography (Hyman et al 1982) industries, where helium is one of the important protected gases. Therefore, in group B, we set the gas as helium and the corresponding half-height is h = 5 cm.…”

Section: Direct Numerical Simulations Of Fluid and Particlesmentioning

confidence: 96%

“…To understand the effect of the fluid inertial torque induced by the particle inertia in TCF, we ignore gravity intentionally to focus on particle-fluid interactions. Although in some applications, such as in the nuclear (Molyneaux et al 2017) and lithography (Hyman et al 1982) industries, the particle-to-fluid density ratio is extremely large, the gravity effect can be neglected if the particle Froude number is much larger than one (Sardina et al 2012;Milici & De Marchis 2016).…”

Section: Importance Of Fluid Inertial Torquementioning

confidence: 99%

“…Although in some applications, such as in the nuclear (Molyneaux et al. 2017) and lithography (Hyman et al. 1982) industries, the particle-to-fluid density ratio is extremely large, the gravity effect can be neglected if the particle Froude number is much larger than one (Sardina et al.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Effect of fluid inertial torque on the rotational and orientational dynamics of tiny spheroidal particles in turbulent channel flow

Cui,

Qiu,

Jiang

et al. 2023

J. Fluid Mech.

View full text Add to dashboard Cite

Rotation and orientation of non-spherical particles in a fluid flow depend on the hydrodynamic torque they experience. However, little is known about the effect of the fluid inertial torque on the dynamics of tiny inertial spheroids in turbulent channel flows, as only Jeffery torque has been considered in previous studies by point-particle direct numerical simulations. In this study, we investigate the rotation and orientation of tiny spheroids with both fluid inertial torque and Jeffery torque in a turbulent channel flow. By comparing with the case in the absence of fluid inertial torque, we find that the rotational and orientational dynamics of spheroids is significantly affected by the fluid inertial torque when the Stokes number, which is non-dimensionalized by fluid viscous time scale, is larger than the critical value $St_c\approx 2$ , indicating that the fluid inertial torque is non-negligible for most particle cases considered in earlier studies. In contrast to the earlier findings considering only Jeffery torque (Challabotla et al., J. Fluid Mech., vol. 776, 2015, p. R2), we find that prolate (oblate) spheroids with a large Stokes number tend to tumble (spin) in the streamwise–wall-normal plane in a thinner region near the wall due to the presence of the fluid inertial torque. Approaching the channel centre, the flow shear gradually vanishes, but the velocity difference between local fluid and particles is still pronounced and increasing as particle inertia grows. As a result, in the core region, fluid inertial torque is dominant and drives the particles to align with its broad side normal to the streamwise direction rather than a random orientation observed in earlier studies without fluid inertial torque. Meanwhile, the presence of fluid inertial torque enhances the tumbling rates of spheroids in the core region. In addition, the effect of fluid inertial force on the dynamics of spheroids is also examined in this study, but the results indicate the effect of fluid inertial force is weak. Our findings imply the importance of fluid inertial torque in modelling the dynamics of inertial non-spherical particles in turbulent channel flows.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 96%

Section: Direct Numerical Simulations Of Fluid and Particlesmentioning

confidence: 96%