Documents disponibles écrits par cet auteur

Active compressor stability management via a stall margin control mode / Yuan Liu in Transactions of the ASME . Journal of engineering for gas turbines and power, Vol. 132 N° 5 (Mai 2010) 

Public ISBD [article]  in Transactions of the ASME . Journal of engineering for gas turbines and power > Vol. 132 N° 5 (Mai 2010) . - 10 p. Titre : Active compressor stability management via a stall margin control mode Type de document : texte imprimé Auteurs : Yuan Liu, Auteur ; Manuj Dhingra, Auteur ; J. V. R. Prasad, Auteur Année de publication : 2011 Article en page(s) : 10 p. Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Aerospace  engines  Aircraft  control  Compressors  Gas  turbines  Stability Index. décimale : 620.1 Essais des matériaux. Défauts des matériaux. Protection des matériaux Résumé : An active engine control scheme for protection against compressor instabilities such as rotating stall and surge is presented. Compressor stability detection is accomplished via a parameter known as the correlation measure, which quantifies the repeatability of the pressure fluctuations in the tip region of a compressor rotor. This work investigates the integration of the correlation measure with an aircraft engine control system through the use of a stall margin control mode. The development and implementation of the stall margin mode are described. The effectiveness of the overall active control framework—an active compressor stability management system—is assessed using a computer simulation of a high-bypass, dual-spool, commercial-type turbofan engine. DEWEY : 620.1 ISSN : 0742-4795 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JETPEZ000132000005 [...] [article] Active compressor stability management via a stall margin control mode [texte imprimé] / Yuan Liu, Auteur ; Manuj Dhingra, Auteur ; J. V. R. Prasad, Auteur . - 2011 . - 10 p. Génie Mécanique Langues : Anglais (eng) in Transactions of the ASME . Journal of engineering for gas turbines and power > Vol. 132 N° 5 (Mai 2010) . - 10 p. Mots-clés : Aerospace  engines  Aircraft  control  Compressors  Gas  turbines  Stability Index. décimale : 620.1 Essais des matériaux. Défauts des matériaux. Protection des matériaux Résumé : An active engine control scheme for protection against compressor instabilities such as rotating stall and surge is presented. Compressor stability detection is accomplished via a parameter known as the correlation measure, which quantifies the repeatability of the pressure fluctuations in the tip region of a compressor rotor. This work investigates the integration of the correlation measure with an aircraft engine control system through the use of a stall margin control mode. The development and implementation of the stall margin mode are described. The effectiveness of the overall active control framework—an active compressor stability management system—is assessed using a computer simulation of a high-bypass, dual-spool, commercial-type turbofan engine. DEWEY : 620.1 ISSN : 0742-4795 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JETPEZ000132000005 [...]

Correlation measure-based stall margin estimation for a single-stage axial compressor / Yuan Liu in Transactions of the ASME . Journal of engineering for gas turbines and power, Vol. 134 N° 1 (Janvier 2012) 

Public ISBD [article]  in Transactions of the ASME . Journal of engineering for gas turbines and power > Vol. 134 N° 1 (Janvier 2012) . - 09 p. Titre : Correlation measure-based stall margin estimation for a single-stage axial compressor Type de document : texte imprimé Auteurs : Yuan Liu, Auteur ; Manuj Dhingra, Auteur ; J. V. R. Prasad, Auteur Année de publication : 2012 Article en page(s) : 09 p. Note générale : Génie mécanique Langues : Anglais (eng) Mots-clés : Aircraft  control  Compressors  Correlation  methods  Gas  turbines  Rotors  Stability Index. décimale : 620.1 Essais des matériaux. Défauts des matériaux. Protection des matériaux Résumé : This paper presents a method for estimating compressor stall margin and the results of applying the estimation technique to an axial compressor rig. Stall margin estimation is accomplished through the use of a compressor stability detection parameter called the “correlation measure.” The correlation measure captures the periodicity of the pressure in the rotor tip region of the compressor. The downcrossing frequency of the correlation measure across some preset threshold is measured while operating the compressor rig at various steady-state points along the design speed characteristic line. These measurements are used to generate a relationship with stall margin as a function of downcrossing frequency. The estimation technique is evaluated by applying it while dynamically ramping the operating point of the compressor up the design speed line towards surge. A brief investigation on the effects of inlet distortions on the correlation measure-based estimation system is also given. DEWEY : 620.1 ISSN : 0742-4795 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JETPEZ000134000001 [...] [article] Correlation measure-based stall margin estimation for a single-stage axial compressor [texte imprimé] / Yuan Liu, Auteur ; Manuj Dhingra, Auteur ; J. V. R. Prasad, Auteur . - 2012 . - 09 p. Génie mécanique Langues : Anglais (eng) in Transactions of the ASME . Journal of engineering for gas turbines and power > Vol. 134 N° 1 (Janvier 2012) . - 09 p. Mots-clés : Aircraft  control  Compressors  Correlation  methods  Gas  turbines  Rotors  Stability Index. décimale : 620.1 Essais des matériaux. Défauts des matériaux. Protection des matériaux Résumé : This paper presents a method for estimating compressor stall margin and the results of applying the estimation technique to an axial compressor rig. Stall margin estimation is accomplished through the use of a compressor stability detection parameter called the “correlation measure.” The correlation measure captures the periodicity of the pressure in the rotor tip region of the compressor. The downcrossing frequency of the correlation measure across some preset threshold is measured while operating the compressor rig at various steady-state points along the design speed characteristic line. These measurements are used to generate a relationship with stall margin as a function of downcrossing frequency. The estimation technique is evaluated by applying it while dynamically ramping the operating point of the compressor up the design speed line towards surge. A brief investigation on the effects of inlet distortions on the correlation measure-based estimation system is also given. DEWEY : 620.1 ISSN : 0742-4795 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JETPEZ000134000001 [...]

Experimental analysis of a waveguide pressure measuring system / Matthew A. White in Transactions of the ASME . Journal of engineering for gas turbines and power, Vol. 132 N° 4 (Avril 2010) 

Public ISBD [article]  in Transactions of the ASME . Journal of engineering for gas turbines and power > Vol. 132 N° 4 (Avril 2010) . - 07 p. Titre : Experimental analysis of a waveguide pressure measuring system Type de document : texte imprimé Auteurs : Matthew A. White, Auteur ; Manuj Dhingra, Auteur ; J. V. R. Prasad, Auteur Année de publication : 2010 Article en page(s) : 07 p. Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Aerospace  engines  Blades  Compressors  Frequency  response  Gas  turbines  Pressure  measurement  Pressure  transducers  Probes Index. décimale : 620.1 Essais des matériaux. Défauts des matériaux. Protection des matériaux Résumé : An infinite-line probe is commonly used to measure unsteady pressure in high-temperature environments while protecting the pressure transducer. In this study, an existing theoretical model is used to derive the response of a waveguide pressure measuring system. An ambient temperature centrifugal compressor rig acts as an experimental source of fluctuating pressure. The compressor is operated at different discrete rotational speeds, and the blade-passing frequencies are used to obtain frequency response data. In the experiments, pressure waves attenuated at a rate faster than that predicted by the theoretical model for a 0.322 m (12 in.) sensor offset. Furthermore, the decay in the magnitude of the pressure oscillations accelerated at blade-passing frequencies above 9 kHz. A unique contribution of this study is to show that whereas the experimentally observed overall attenuation is broadly consistent with the theoretical predictions, pressure oscillations corresponding to individual blade passages may be disproportionally attenuated. DEWEY : 620.1 ISSN : 0742-4795 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JETPEZ000132000004 [...] [article] Experimental analysis of a waveguide pressure measuring system [texte imprimé] / Matthew A. White, Auteur ; Manuj Dhingra, Auteur ; J. V. R. Prasad, Auteur . - 2010 . - 07 p. Génie Mécanique Langues : Anglais (eng) in Transactions of the ASME . Journal of engineering for gas turbines and power > Vol. 132 N° 4 (Avril 2010) . - 07 p. Mots-clés : Aerospace  engines  Blades  Compressors  Frequency  response  Gas  turbines  Pressure  measurement  Pressure  transducers  Probes Index. décimale : 620.1 Essais des matériaux. Défauts des matériaux. Protection des matériaux Résumé : An infinite-line probe is commonly used to measure unsteady pressure in high-temperature environments while protecting the pressure transducer. In this study, an existing theoretical model is used to derive the response of a waveguide pressure measuring system. An ambient temperature centrifugal compressor rig acts as an experimental source of fluctuating pressure. The compressor is operated at different discrete rotational speeds, and the blade-passing frequencies are used to obtain frequency response data. In the experiments, pressure waves attenuated at a rate faster than that predicted by the theoretical model for a 0.322 m (12 in.) sensor offset. Furthermore, the decay in the magnitude of the pressure oscillations accelerated at blade-passing frequencies above 9 kHz. A unique contribution of this study is to show that whereas the experimentally observed overall attenuation is broadly consistent with the theoretical predictions, pressure oscillations corresponding to individual blade passages may be disproportionally attenuated. DEWEY : 620.1 ISSN : 0742-4795 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JETPEZ000132000004 [...]