... coatings are applied resulting in contact angles of 51–95 deg. The inflow Mach number was fixed at design inflow Mach number, and the inflow angle was varied over a broad range. The effect on the water film pattern is analyzed in terms of position of film breakup, rivulet width, and totally wetted surface...

... viscosity together with flow viscosity forms the effective viscosity, which is the coefficient of the shear stress in the film. The turbulence model and Reynolds equation are bound together to solve when hydrodynamic analysis is performed, therefore improving the accuracy of the turbulence model is also...

...Yunus Emre Ayranci; Ozgen Akalin Measurement of film thickness between piston ring and cylinder bore has been a challenge for decades; laser-induced fluorescence (LIF) method was used by several groups, and promising results are obtained for the investigation of lubricant film transport...

... to improve the performance of the overall system. This could potentially be implemented in all rotordynamic systems supported by AMBs and subjected to seal forces or other fluid film forces. References [1] Childs , D. W. , 1993 , Turbomachinery Rotordynamics: Phenomena, Modeling, and Analysis...

... For compliant foil bearings, relatively high hydrodynamic film stiffness is beneficial since the dynamic behavior may be dominated by the compliant structure's stiffness and damping. However, high film stiffness requires small film thickness or operating clearances, which have drawbacks of reduced load capacity...

... clearance increases as the supply pressure increases and decreases quickly as the applied load increases. The reduction in clearance increases the flow resistance across the film lands, thus reducing the through flow rate with an increase in recess pressure. In addition, an estimated bearing axial stiffness...

... that direct lubrication TPJBs exhibit unexpected shaft vibrations with a broadband low frequency range, albeit small in amplitude. Published industrial practice demonstrates the inlet lubrication type, a reduced supply flow rate causing film starvation, and the bearing discharge conditions (evacuated or end...

...Craig Nolen; Melissa Poerner The distribution of water in the diffuser of a wet gas compressor is not well understood. Measurements of water film thickness across the diffuser surface would improve the understanding of two-phase flow phenomena in wet gas compressors. Electromagnetic probes were...

..., 2017. Assoc. Editor: Klaus Brun. 30 05 2017 10 07 2017 Aeronautical propulsion Aerospace applications Design optimization Droplet Experimental Film Fluids Gas turbine technology Multiphase flows Separated Shear Flows Turbulent Two-phase Unsteady Aerospace Propulsion...

...Pietro Rossi; Asad Raheem; Reza S. Abhari Formation of thin liquid films on steam turbine airfoils, particularly in last stages of low-pressure (LP) steam turbines, and their breakup into coarse droplets is of paramount importance to assess erosion of last stage rotor blades given by the impact...

...Luis San Andrés; Sean Den; Sung-Hwa Jeung Gas turbine aircraft engine manufacturers push for simple squeeze film damper (SFD) designs, short in length, yet able to provide enough damping to ameliorate rotor vibrations. SFDs employ orifices to feed lubricant directly into the film land...

...Guanghua Wang; Gustavo Ledezma; James DeLancey; Anquan Wang Gas turbines overall efficiency enhancement requires further increasing of the firing temperature and decreasing of cooling flow usage. Multihole (or effusion, or full-coverage) film cooling is widely used for hot gas path components...

... to static angular misalignments of the TC and BG surfaces that affect the operating film thickness as well as the force and reaction moments of the lubricated mechanical element. In a follow-up to San Andrés et al. (2015, “On the Predicted Performance of Oil Lubricated Thrust Collars in Integrally Geared...

... removing the film and effusion cooling jet geometry from the liner while retaining the cooling hole imprints on the liner. The PAPRICO can operate under two modalities, viz., two-sided and one-sided. For the two-sided PAPRICO model, the imprints are kept on the plenum and combustor sides of the liner...

... manuscript received August 28, 2015; published online September 13, 2016. Editor: David Wisler. 11 08 2015 28 08 2015 Aerodynamics Film Modeling The general working principle for foil gas bearing is as follows: when journal starts to rotate, air is drawn into the bearing via...

... FOR G AS T URBINES AND P OWER . Manuscript received June 20, 2016; final manuscript received June 28, 2016; published online September 8, 2016. Editor: David Wisler. 20 06 2016 28 06 2016 Computational fluid dynamics Droplet Film Fluids Modeling Multiphase flows Periodic...

...Luis San Andrés; Sean Den; Sung-Hwa Jeung Commonly employed in air breathing (gas turbine) engines, squeeze film dampers (SFDs) reduce the amplitude of rotor vibration while traversing system critical speeds or in transient events such as during a maneuver load, a hard landing, a blade loss...

...Bruce Kakimpa; Herve Morvan; Stephen Hibberd Thin-film flows encountered in engineering systems such as aero-engine bearing chambers often exhibit capillary waves and occur within a moderate to high Weber number range. Although the depth-averaged simulation of these thin-film flows...

...Yin Song; Chun-wei Gu Computational fluid dynamics (CFD) analysis, which solves the full three-dimensional (3D) Navier–Stokes equations, has been recognized as having promise in providing a more detailed and accurate analysis for oil-film journal bearings than the traditional Reynolds analysis...

...Zhao Jingyu; Liu Zhenxia The oil film thickness on the bearing chamber wall directly affects the wall heat transfer efficiency, so a fundamental study on the motion of oil film on the rotating cylinder has been conducted to this end. On the one hand, the rotating cylinder test rig was designed...