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Ma C.-W.,Shenyang Aerospace Engine Research Institute
Applied Mechanics and Materials

Thermal paints, as a kind of temperature sensor, provided a non-intrusive method for surface temperature measurement. Based on chromaticity theory, the system described in this paper realized thermal paints temperature intelligent interpretation with digital image processing and database technology. The system overcome the effects of subjective interpretation, environment light and human color discrimination ability and made the analysis more accurate and consistent than manual interpretation. The digital image acquisition system was described in detail. Cubic spline interpolation algorithm was adopted to process the data in the L*a*b* color space. The system had been applied to measure the surface temperature of aero-engine combustor. The results showed that the system can greatly improve the accuracy of temperature-recognition. © (2010) Trans Tech Publications. Source

Huang X.,Nanjing University of Aeronautics and Astronautics | Wang Y.,Shenyang Aerospace Engine Research Institute | Sheng L.,Nanjing University of Aeronautics and Astronautics
Proceedings of the American Control Conference

Propeller synchrophasing control is an active noise control technology with high feasibility and significant effect among various kinds of passive and active methods. A simple and effective synchrophasing control strategy was proposed based on the relationship analysis of phase and angular displacement. Digital simulations and experiments of synchrophasing platform which adopts two propellers driven by servo motors verified that the control strategy can reduce the phase vibration because of external disturbance on propellers. Two synchrophasing control methods, including speed command correction and integrated speed/power command correction, are introduced to solve the synchrophasing control on the existing integrated speed/command control system. Simulation results based on a turboprop engine component level model show that the latter has the merits of rapid response swiftness, high precision and effective suppression of limit circle caused by actuator deadband. © 2015 American Automatic Control Council. Source

Li Y.,Beihang University | Xu G.,Beihang University | Deng H.,Beihang University | Qiu L.,Beihang University | Yu X.,Shenyang Aerospace Engine Research Institute
International Journal of Heat and Mass Transfer

Heat transfer characteristics of a novel turbine blade trailing edge internal cooling concept, two-inlet wedge-shaped channel with lateral fluid extraction, are experimentally investigated under both rotating and non-rotating conditions. In order to improve the heat transfer of the channel, a second coolant inlet is introduced in the vicinity of the low heat transfer region that previously observed in single-inlet configuration. The mass flow rate ratio (MR, second inlet mass flow rate/major inlet mass flow rate) ranges from 0 to 1. The major inlet Reynolds number and rotation number are varied from 6000 to 24,000 and 0 to 0.23, respectively. The results show that the second inlet coolant injection decreases local bulk temperature and increases local heat transfer at the high-radius half channel. In rotating cases, the second inlet notably improves the heat transfer at the top of the channel and compensates the negative effects induced by the rotation. The effect of the additional inlet is only significant in the vicinity of the coolant injection in both non-rotating and rotating cases. Moreover, with a MR of under 0.3, the second coolant injection benefits overall wall heat transfer at high rotation numbers. © 2016 Elsevier Ltd. All rights reserved. Source

Huang X.,Nanjing University of Aeronautics and Astronautics | Sheng L.,Nanjing University of Aeronautics and Astronautics | Wang Y.,Shenyang Aerospace Engine Research Institute
Journal of Engineering for Gas Turbines and Power

Propeller synchrophasing is an effective way of reducing interior noise and vibration of turboprop-driven aircraft. However, synchrophasing has achieved limited success in practice for the reason that the predetermined phase angles are not acoustically optimized for maximum noise reduction during all flight conditions. An investigation has been conducted out which includes two folds: first, the noise vector based on laboratory experimental data has been modeled and second, optimal phase to acquire minimum noise is obtained via optimization search. An improved identification method of vector noise model which can be less dependent to noise phase message is presented. Compared with traditional methods, this method can greatly reduce the real-time requirement between phase optimization model and control model or sound acquiring model, so it can eliminate the influence which communication delay brings on identification precision. A synchrophasing experimental platform is established to verify the vector noise modeling. It adopts two propellers-driven servo motors to simulate the interior noise environment of the aircraft. The influence of the date sampling condition on identification is also researched. Ant colony optimization with two improvements is applied to phase optimization of four propellers. Simulation results show that the improved algorithm requires much less calculation. © 2014 by ASME. Source

Liu D.,Beihang University | Tao Z.,Beihang University | Luo X.,Beihang University | Wu H.,Northumbria University | Yu X.,Shenyang Aerospace Engine Research Institute
Journal of Engineering for Gas Turbines and Power

This article presents a further investigation on the mechanism of hot gas ingestion by exploring the ingress with complicated cavity generated by the rotor-mounted cylinder protrusion. During the experiment, a cavity with 32 cylinder protrusions circumferentially distributed in rotor that contained 59 blades is applied. The annulus Reynolds number and rotating Reynolds number are fixed to be 1.77 105 and 7.42 105, respectively, while the dimensionless sealing air flow rate ranges from 3047 to 8310. The measurement of CO2 concentration and pressure is conducted. Experimental results show that the sealing efficiency is improved with the introduction of the cylinder protrusions even the static pressure inside cavity is found to be reduced. The effect of the circumferentially nonuniform cavity pressure wave is considered and added into the orifice model, and the effect of some impact factors, i.e., the amplitude, initial phase angle difference, and frequency of the cavity pressure wave, on hot gas ingestion is theoretically discussed in detail. However, it is noted that the cavity pressure wave that was introduced by 32 cylinder rotor-mounted protrusions is found to have insignificant effect on improving the sealing efficiency. In the present study, a modified orifice model that takes the tangential velocity into account is proposed and a new factor H is introduced to well explain the mechanism of the ingress. © 2016 by ASME. Source

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