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Showing 1 to 15 of 15 for “"vaned"”.
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One-Dimensional Performance Modeling of Centrifugal Flow Vaned Diffusers
… Chi5, and DELTA5p, for two different types of vaned diffusers, channel and cascade, are proposed. These models were developed with frozen impeller modeling. This is the first time that modeling the TEIS and Two Zone input parameters has been attempted for vaned diffusers and impeller-diffuser …
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Scalloped Leading Edge Vaned Diffuser Analysis for a Compact High Pressure Ratio Centrifugal Compressor
… propulsion applications. The first stage vaned diffuser was modified to include a scalloped leading edge ridge to aid stage total-total compression efficiency improvement. A full 3D Navier-Strokes based CDF solver was used in estimating the delta increase in device total-total efficiency …
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A computational investigation of the effects of inlet flow conditions on vaned diffuser performance
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1997.
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A computational study of the 3D flow and performance of a vaned radial diffuser
A computational study was performed on a vaned radial diffuser using the MEFP (The Moore Elliptic Flow Program) flow code. The vaned diffuser studied by Dalbert et al. was chosen as a test case for this thesis. The geometry and inlet conditions were established from this study. The performance of …
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The role of impeller outflow conditions on the performance and stability of airfoil vaned radial diffusers
… ratio 5 tur-bocharger compressor with an airfoil vaned diffuser. The swirling flow rig is able to generate rotor outflow conditions representative of the compressor except for the periodic pitchwise unsteadiness, and ts a 0.86 scale diffuser and volute. In both rigs, the time-mean impeller outflow …
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Simulation of spike stall inception in a radial vanted diffuser
… in centrifugal compressors can be formed by a vaned diffuser. To address these issues, a numerical study on an advanced, vaned-diffuser centrifugal compressor was conducted to investigate stall inception. A steady three-dimensional Reynolds-averaged Navier-Stokes simulation using a mixing plane …
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Computational Assessment of Flow through a High-Flow Nacelle Bypass for Low Supersonic Boom
… vane calculations were conducted in “clean” and “vaned” configurations which correspond to experimental models whose data were used for validation purposes. Comparisons between the full engine and detailed single channel calculations show a weak dependence on the turbulence model used for the mean …
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Numerical Study Of A High-speed Miniature Centrifugal Compressor
… splitters. Based on numerical study, a four-row vaned diffuser was used to replace a two-row vaned diffuser. It was found that the four-row vaned diffuser had much higher pressure recovery coefficient than the two-row vaned diffuser. However, most of pressure is found to be recovered at the first …
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Area-schedule based design of high pressure recovery radial diffusion systems
… is developed based on area scheduling the vaned diffuser. The vaned diffuser and volute designs are assessed numerically through RANS calculations and validated by full-scale compressor experiments. The investigations revel that it is mainly the diffuser area ratio and effective …
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Investigation of stall inception in centrifugal compressors using isolated diffuser simulations
… role, but spikes can also occur in shrouded vaned diffusers of centrifugal compressors, where these flows are not present, suggesting an alternative mechanism may be at play. Unsteady Reynold's Averaged Navier-Stokes simulations are performed for an isolated vaned radial diffusers from a …
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A comparison of bi-directional disc brake rotor passage designs
… rotors is generally more uniform than from vaned rotors. Subsequent conjugate heat transfer simulations found that temperature gradients inside pillared rotors are typically lower than inside vaned rotors. Thus failure rates due to excessive thermal strain are expected to be lower for …
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A methodology for centrifugal compressor stability prediction
… in highly-loaded centrifugal compressors with vaned diffusers. The approach, based on a body force representation of the blade rows, is different from previous research in that the prediction is independent of compressor stability correlations and a-priori knowledge of the compressor …
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Direct Chain-End Functionalization of Living Polyisobutylene With Phenoxyalkyl(meth)acrylates
… while the ratio of Lewis ac1d/cham end was vaned from approximately 3 5-6 In all cases, alkylation occurred exclusively at the para position of the quencher and no cham degradat10n was observed, even at high concentrations of TiC14 and long reaction times. Prellmmary qualitative studies …
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An experimental investigation of a low Reynolds number, high Mach number centrifugal compressor
… by 2-D and 3-D CFO. The performance of the vaned diffuser (Cp=0.48) is superior to that of the vaneless diffuser (Cp=0.24) in recovering the dynamic pressure of air exiting the impeller. The impeller isentropic efficiencies are about 0.48 and 0.27 for 100% and 42% design impeller speeds, …
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Robust State Estimation, Uncertainty Quantification, and Uncertainty Reduction with Applications to Wind Estimation
… during UAS flight tests and validated using a vaned air data unit onboard the aircraft. The H∞ filter provides quantitatively better estimates of the wind than the KALMAN-BUCY filter, with approximately 10-40% less root-mean-square (RMS) error in the majority of cases. It is also shown that …