.... The convective wall heat loss is modeled through introducing a source term in the conditionally filtered total enthalpy equation for the CMC cells adjacent to the wall. The mean heat flux is high on the middle surface of the bluff body, but relatively low near its edges. The turbulent heat flux based...

..., the instantaneous flame location can vary in thickness and location due to heat losses or imperfect mixing. Postflame phenomena (slow CO oxidation or thermal NO production) can be expected to be significantly influenced by turbulent eddy structures. Since typical gas turbine combustor calculations require insight...

...), whereas the flow on the blade pressure side close to the band was accelerating (turbine) and directed toward the outlet. Flow separation from the blade leading edge created a vortical flow, which broke up into four parts as it traveled further downstream and created high-energy turbulent eddies...

... zone (TRZ). The Damkohler (Da) number in the reactor is the highest in the stabilization vortex; it varies from about Da ∼ 2 at ϕ = 0.55 to Da ∼ 0.2–0.3 at LBO conditions. Due to the reduced turbulent dissipation rate in PRZ, the Da number is an order of magnitude higher than in TRZ. The global blowout...

... motion results in a faster combustion, hence in a higher efficiency. In summary, the geometrical modifications close to the valve seat result in increased turbulence intensity. It was proven that this intensification raises the ratio of efficiency by 1.6%. 1 Corresponding author. Contributed...

... numbers ranging between 50,000 and 110,000 (with respect to the nozzle diameter, D N ); equivalence ratios between 0.55 and 0.78; and pilot fuel split ratios of 0 to 6%. Characterizing the impingement location on the liner, and the turbulent kinetic energy (TKE) distribution were a fundamental part...

... velocity profiles show that, as flow develops axially, the vortex present in the profile migrates clockwise, opposite to the rotation of the fan, and toward the spinner of the engine. The turbulent stresses indicate that the center of the vortex meanders around a preferred location, which tightens as flow...

.... It is then shown that the axial velocity field produced by the axial-plus-tangential swirler is different from those produced by purely axial or radial devices. It takes here a W-shape profile with three local maxima and two minima. The mean turbulent flame front also takes this W-shape in an axial plane, with two...

... Wisler. 26 07 2017 09 08 2017 Aeronautical propulsion Aerothermodynamics Combustion Combustors Computational fluid dynamics Engines Flame Fuel combustion Fuels Gas turbine technology Modeling Multiphase flows Sprays Swirling Turbulence Turbulent Two-phase Unsteady...

... of the long mixing duct can be seen at the very left. The mixing duct has a diameter of 40 mm and is off-centered to the combustion chamber axis by 10 mm. Thus, the fuel/air mixture enters the combustion chamber as an off-centered partially premixed turbulent jet flow. This off-centered setup allows...

... , J.-F. , Durox , D. , Schuller , T. , and Candel , S. , 2013 , “ Tomographic Reconstruction of Heat Release Rate Perturbations Induced by Helical Modes in Turbulent Swirl Flames ,” Exp. Fluids , 54 , p. 1498 . 10.1007/s00348-013-1498-2 [21] Bourgouin , J. , Durox , D...

... decomposition [ 24 ], but it offers a more precise selectivity, which provides benefits in complex turbulent flows like the swirling jet investigated here [ 19 ]. In the following, only a short overview of the SPOD approach is given. A detailed derivation can be found in Ref. [ 18 ]. The procedure...

... a turbulent frothy flow. Subsequent oil film flow is a result of the tangential momentum that the droplets bring to the impact, the shear of the air on the oil, and the impact or splashing of subsequent droplets. Other forces include gravity, as well as capillary effects. Ideally oil flows out of the bearing...

..., Turbul. Combust. , 88 ( 1–2 ), pp. 191 – 206 . 10.1007/s10494-011-9367-7 [17] Wolf , P. , Staffelbach , G. , Gicquel , L. , Müller , J.-D. , and Poinsot , T. , 2012 , “ Acoustic and Large Eddy Simulation Studies of Azimuthal Modes in Annular Combustion Chambers ,” Combust...

... ), pp. 1 – 14 . 10.1007/BF02560457 [12] Zhang , Q. , Liu , H. , Ma , Z. , and Xiao , Z. , 2016 , “ Preferential Concentration of Heavy Particles in Compressible Isotropic Turbulence ,” Phys. Fluids , 28 ( 5 ), p. 055104 . 10.1063/1.4948810 [13] Hammitt , F. , Hwang...

... between the ignition probability field and the airflow turbulent kinetic energy and velocity fields. Local equivalence ratio enhances the importance of the ORZ. Once a successful ignition is accomplished on one injector, the injector-to-injector flame propagation must be examined. High-speed visualization...

... Wisler. 03 07 2017 04 07 2017 Computational fluid dynamics Turbulent Vibration Multiple stage centrifugal pumps comprise several impellers mounted on a single shaft spinning inside a barrel. These pumps rely on a number of sealing elements that restrict secondary flow...

...Michael Stöhr; Kilian Oberleithner; Moritz Sieber; Zhiyao Yin; Wolfgang Meier Sudden changes of flame shape are an undesired, yet poorly understood feature of swirl combustors used in gas turbines. The present work studies flame shape transition mechanisms of a bistable turbulent swirl flame...

... upstream of the HGV centerbody trailing edges, and D3 occurs immediately downstream. The flow solver used for this study was fluent v16.2. The general approach to the solver settings were based on the recommendations of Mongia [ 19 ]. Thus, turbulence modeling utilized a realizable k − ε...

...Andrew Marshall; Julia Lundrigan; Prabhakar Venkateswaran; Jerry Seitzman; Tim Lieuwen Fuel composition has a strong influence on the turbulent flame speed, even at very high turbulence intensities. An important implication of this result is that the turbulent flame speed cannot be extrapolated...