... for Nimonic-air coupling (values of k for Nimonic from Ref. 38 ) 01 12 2010 11 02 2011 21 07 2011 21 07 2011 blades cooling finite element analysis infrared imaging jets turbines Modern gas turbine engines use strong cooling in key components of the turbine...

.... Two jet-to-cross-flow velocity ratios have been considered: VR = 1 and 2, which correspond to blowing ratios of 1 and 2, respectively. The pulsating frequency is 10 Hz and the duty cycle is 50%. Comparisons between film effectiveness with a pulsating film and a continuous film show that for the same...

... in some respect. The more detailed 3D geometry did not significantly improve the comparison with experiment, which suggests deficiencies in the turbulence modeling, particularly in the complex mixing region near the preswirl nozzle jets. The predicted heat transfer near the receiver holes was also shown...

... jets, each impinging on a different adjacent wall. The ribs are aligned with the inclined jet axes, have the same pitch, and are staggered to the impinging jets. The flow exhausts through two staggered rows of holes opposing the impingement wall. The passage geometry is related to a modern gas turbine...

... spanwise rows of discrete vortex generator jets. The jets were located at 59% C x , approximately the peak c p location, and at 72% C x . The most effective separation control was achieved at the upstream location. The wake total pressure loss decreased 60% from the wake-only level and the c p distribution...

... hybridization makes further sense for compressible flow solvers, where, as the Mach number tends to zero at walls, excessive dissipation can occur. The hybrid strategy is used to predict flow over a rib roughened surface and a jet impinging on a convex surface. These cases are important for blade cooling...

...Wilhelm Jessen; Martin Konopka; Wolfgang Schroeder The turbulent flow field of a film cooling flow is investigated using the particle-image velocimetry technique. Cooling jets are injected from a multirow hole configuration into a turbulent boundary layer flow of a flat plate in the presence...

...Ting Wang; T. S. Dhanasekaran Internal mist/steam blade cooling technology is proposed for advanced gas turbine systems that use the closed-loop steam cooling scheme. Previous experiments on mist/steam heat transfer with a 2D slot jet impingement onto a concave surface showed cooling enhancement...

... image velocimetry and high speed photography. Coherent unsteadiness is found in the shear layer between the jet and the mainstream for both cylindrical and fan-shaped cooling holes. Its occurrence and sense of rotation is found to be controlled by the velocity difference between the mainstream flow...

... of the effect of the waist-shaped slot hole’s structure. The middle constriction structure of the waist-shaped slot hole and the coupled vortices makes jets from the waist-shaped slot holes produce higher cooling effectiveness in the midspan region between adjacent holes. And also due to the effect...

...Lesley M. Wright; Stephen T. McClain; Michael D. Clemenson An experimental investigation of film cooling jet structure using two-dimensional particle image velocimetry (PIV) has been completed for cylindrical, simple angle ( θ = 35 deg ) film cooling holes. The PIV measurements are coupled...

...Ralph J. Volino; Olga Kartuzova; Mounir B. Ibrahim Boundary layer separation control has been studied using vortex generator jets (VGJs) on a very high lift, low-pressure turbine airfoil. Experiments were done under high (4%) freestream turbulence conditions on a linear cascade in a low speed wind...

..., a transition occurs, leading to increased effectiveness with the elevated density ratio ( DR = 1.4 ) . In addition, the PSP technique captures an upstream shift of the coolant jet reattachment point as the density ratio increases or the turbulence intensity increases (at moderate blowing ratios for cylindrical...

...Xinqian Zheng; Yangjun Zhang; Weidong Xing; Junyue Zhang Flow separation control was investigated on a compressor cascade using three types of fluidic-based excitations: steady suction, steady blowing, and synthetic jet. By solving unsteady Reynolds–averaged Navier–Stokes equations, the effect...

... the cooling air to the trailing-edge channel through a row of racetrack-shaped slots on the partition wall between the two channels. Eleven crossover jets issued from these slots entered the trailing-edge channel and exited from a second row of race-track shaped slots on the opposite wall in staggered...

... with the flow field visualizations presented in part I of this paper. The results show the dramatic impact of the flow structures on the local and global heat transfer coefficients along the cavity walls. Of particular importance is the jet deflected by the rib-roughened wall and impinging on the opposite...

...Mark Ricklick; J. S. Kapat High performance turbine airfoils are typically cooled with a combination of internal cooling channels and impingement. In such applications, the jets impinge against a target surface, and then exit along the channel formed by the jet plate, target plate, and side walls...

... in order to point out the role of cooling air injection position, swirl number, and jet penetration on the cavities’ sealing performance. Steady state calculations were performed using two different computational domains: the first consists of a sector model of the whole turbine including the second stator...

...% of the efficiency improvement seen with low suction, while the second endwall design exhibits a 34% deterioration. The time-resolved computations show that the rotor dominates the static pressure field at the rim seal exit when purge flow is present. Therefore, the purge flow establishes itself as jets emerging...

... increasing, the normalized heat transfer coefficient h ∕ h 0 of both consoles increases. In the upstream, the heat transfer coefficient of console with small exit-entry area ratio is higher. But in the downstream, the jets’ turbulence and the couple vortices play notable elevating effect on the heat transfer...