Collaborative Innovation Center for Advanced Aerospace Engine
Collaborative Innovation Center for Advanced Aerospace Engine
Hu H.,Beihang University |
Wang Q.,Beihang University |
Wang Q.,Collaborative Innovation Center for Advanced Aerospace Engine
Journal of Heat Transfer | Year: 2017
The multiscale multigroup full-spectrum k-distribution (MSMGFSK) model was improved to adapt to radiation heat transfer calculations of combustion gas flow field with large temperature and pressure gradient. The improvements in calculation accuracy resulting from new sorting strategy of the spectral absorption coefficients were validated using a series of semi-1D problem in which strong temperature, pressure, and mole fraction inhomogeneities were present. A simpler method to attain compatibility between the MSMGFSK model and the gray-wall radiation emission has been established and validated. Finally, estimates are given for the calculation of wall radiation heat transfer characteristics and thermal emission imaging of the exhaust system of the parallel turbine-based combined cycle (TBCC) engine, using finite volume method (FVM) and ray trace method (RT), respectively. © 2017 by ASME.
Tu Z.,Nanjing University of Aeronautics and Astronautics |
Mao J.,Nanjing University of Aeronautics and Astronautics |
Mao J.,Collaborative Innovation Center for Advanced Aerospace Engine |
Han X.,Nanjing University of Aeronautics and Astronautics
Applied Thermal Engineering | Year: 2017
Numerical study was performed to investigate the film cooling performance for a flat plate with anisotropic thermal conductivity where the plate had a single row of round holes. The cooling effectiveness and temperature distribution were analyzed and compared between the results of isotropic and anisotropic plates. The effects of two angles on the cooling effectiveness were studied, i.e. the axial angle α (0°, 30°, 35°, 60° and 90°) and the spanwise angle β (0°, 30°, 60° and 90°), with regards to the inclined angle between the main thermal conductivity in the plate and the mainstream flow direction. The results obtained showed that the anisotropy of the thermal conductivity and the inclined angles affected the cooling effectiveness in a complex way. The highest average cooling effectiveness could be achieved with a specific α or β, depending on the downstream region of the film cooling hole being considered. With the blowing ratio Br = 0.5, the highest cooling effectiveness averaged over the 0–5D and 0–20D downstream regions (with D the diameter of the film cooling hole) could be obtained with an angle of around 35° and 90° for α, respectively. It was found that the uniformity of the cooling effect was improved with a larger β. Moreover, the effects of α and β on the average cooling effectiveness were found to be similar with different Br. However, the uniformity was affected by α and β non-monotonically in different cases of Br. This work demonstrates that proper inclined angle can lead to better film cooling performance. © 2016 Elsevier Ltd
Zhang K.,Beihang University |
Zhou Z.,Beihang University |
Zhou Z.,Collaborative Innovation Center for Advanced Aerospace Engine |
Ma L.,Beihang University
Measurement Science and Technology | Year: 2017
Laser ultrasonics has been investigated for inspecting the quality of a nuclear radiation protection structure. A possibility is proposed to improve the signal to noise ratio (SNR) of a laser ultrasonic inspection system. Then, a nuclear radiation protection structure composed of an AISI 1045 steel sheet connected with a lead alloy sheet by using an epoxy resin adhesive was manufactured with simulated defects. A non-contact laser ultrasonic inspection system, where the measured signals were filtered using a wavelet threshold de-noising method, was established to conduct a series of experiments. The proposed signal processing method can significantly improve the SNR of measured laser ultrasound signals on a rough solid surface. Compared with the SNR of original ultrasonic signals measured in transmission and reflection, the SNR of processed transmitted and reflected signals is improved by 13.8 and 16.6 dB, respectively. Moreover, laser ultrasonic C-scans based on the transmission and pulse-echo method can detect the simulated de-bonding defects, and the relative deviation between the measured sizes and design values is below 9%. Therefore, the laser ultrasonic method combined with effective signal processing can achieve the quantitative characterization of de-bonding defects in nuclear radiation protection structures. © 2016 IOP Publishing Ltd.
Zhong B.,Beihang University |
Wang Y.,Collaborative Innovation Center for Advanced Aerospace Engine |
Wei D.,Beijing Key Laboratory of Aerospace Engine Structure and Strength |
Wang J.,Beijing Key Laboratory of Aerospace Engine Structure and Strength
International Journal of Fatigue | Year: 2016
A new multiaxial fatigue damage parameter is proposed based on the projection path on the π-plane of the loading path. The proposed parameter is suitable for any arbitrary loading path in practical problems. Many materials exhibit strain hardening due to the non-proportional cyclic loading. A brief overview of some important non-proportional effects in multiaxial fatigue is presented, and a new non-proportionality description is defined. A modified multiaxial fatigue life prediction model is established based on the Coffin-Masson equation. Comparing to five classic multiaxial fatigue models, including the maximum effective strain model, the maximum shear strain model, the Fatemi-Socie (FS) model, the Smith-Watson-Topper (SWT) model and Itoh model, the predicted multiaxial fatigue lives of three metallic materials using the proposed model agreed better with the experimental results. © 2017 Elsevier Ltd.
Kong B.,Beihang University |
Li T.,Collaborative Innovation Center for Advanced Aerospace Engine |
Eri Q.,Beihang University
Journal of Alloys and Compounds | Year: 2017
Aeronautical alloys have a good performance on resisting oxidization, corrosion and fatigue in high temperature environments. Therefore, they are not only widely employed in aero-engine but also in nuclear and petroleum industries. The normal spectral emissivity of five alloys in the wavelength ranging 1–15 μm at moderate and high temperature (400–1200 K) is measured. It is found that the emissivity decreases with the increasing of wavelength and increases when temperature rises. The effects of oxidation and flame treatment process are also studied. The results of the oxidized samples indicate that oxidation can enhance the emissivity significantly and alter the wavelength dependent trend. The results of the flame treatment processed samples show that the impurities and defects caused by the flame treatment process moderately increase the emissivity. The experimental data presented in this paper can be used directly to improve the accuracy of radiation computation and other relevant applications. © 2017 Elsevier B.V.
Liu X.,Beihang University |
Liu X.,Collaborative Innovation Center for Advanced Aerospace Engine |
Liu X.,Aircraft Engine Integrated System Safety Beijing Key Laboratory |
Xue N.,Beihang University |
Yuan Y.,Beihang University
PLoS ONE | Year: 2017
This paper proposed a method to update the on-line health reference baseline of the On-Board Engine Model (OBEM) to maintain the effectiveness of an in-flight aircraft sensor Fault Detection and Isolation (FDI) system, in which a Hybrid Kalman Filter (HKF) was incorporated. Generated from a rapid in-flight engine degradation, a large health condition mismatch between the engine and the OBEM can corrupt the performance of the FDI. Therefore, it is necessary to update the OBEM online when a rapid degradation occurs, but the FDI system will lose estimation accuracy if the estimation and update are running simultaneously. To solve this problem, the health reference baseline for a nonlinear OBEM was updated using the proposed channel controller method. Simulations based on the turbojet engine Linear-Parameter Varying (LPV) model demonstrated the effectiveness of the proposed FDI system in the presence of substantial degradation, and the channel controller can ensure that the update process finishes without interference from a single sensor fault. © 2017 Liu et al.This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Gao J.,Beihang University |
Gao J.,Collaborative Innovation Center for Advanced Aerospace Engine |
Li X.,Beihang University |
Lin D.,Beijing Aeronautical Science and Technology Research Institute
23rd AIAA/CEAS Aeroacoustics Conference, 2017 | Year: 2017
In this study the noise generated from the 30P30N highlift airfoil is simulated with a high order spectral difference code. In this simulation, the inflow Mach number is 0.17, and the Reynolds number based on the inflow velocity and the chord length of the airfoil is 1.7 million. Three attack angles, which are 4, 5.5 and 8.5 degrees respectively, are simulated. The time averaged mean flow field, including the velocity profiles in the slat cove, the pressure coefficients on the surface of the airfoil, is presented and compared with the experimental data. The dynamic pressure on the surface of the slat is sampled and compared with the experimental data by other researchers, and a good agreement is obtained. The far field noise, computed with the permeable Ffowcs Williams-Hawkings (FW-H) integration method, is presented and compared with the experimental data, and a good agreement is obtained. The tone noise source is analyzed with a coherence analysis of the dynamic pressure between the slat surface and the near field. © 2017, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.
Li L.,Beihang University |
Li L.,Collaborative Innovation Center for Advanced Aerospace Engine |
Xue Z.,Beihang University |
Li C.,Beihang University |
Li C.,Collaborative Innovation Center for Advanced Aerospace Engine
Materials and Design | Year: 2016
The Pin-Force Model (PFM) and the Enhanced Pin-Force Model (EPFM) for analyzing the mechanical behavior of a composite beam with active materials are widely used because of simplicity and adaptability. However, the PFM and the EPFM overestimated the deformation of composite beams under a small thickness ratio of substrate and actuator. In this paper, the reasons for the above phenomenon are analyzed first. Then a revised model named Modified Pin Force Model (MPFM) is proposed, which involves the factors neglected in previous models. The detailed derivation and description of the models for both unimorph and bimorph bonding forms are given. The bending curvature of a composite beam predicted by the MPFM is compared with that obtained by both the Euler-Bernoulli beam model and finite element analysis. The result shows a good consistency even in the small thickness ratio. Experiments based on MFC materials were performed to validate the MPFM. The results demonstrate that the proposed model can well predict the bending deformation of a composite beam with mounted actuators in the small thickness ratio, which extends the application range of pin-force models. © 2016 Elsevier Ltd.
Lu Z.L.,Xi'an Jiaotong University |
Lu Z.L.,Collaborative Innovation Center for Advanced Aerospace Engine |
Cao J.W.,Xi'an Jiaotong University |
Cao J.W.,Collaborative Innovation Center for Advanced Aerospace Engine |
And 4 more authors.
Journal of Alloys and Compounds | Year: 2015
TiAl intermetallic and SiC ceramic are two kinds of important high-temperature structural material, but it is difficult to fabricate complex high-performance composites of them by traditional methods. In the paper, it is a pioneer study to prepare their composites so as to fabricate turbine blade by the hybrid technology of Stereolithography and gelcasting. Impregnation and pyrolysis behaviors of polycarbosilane were explored for SiC ceramic preparation, and the microstructure evolution and mechanical properties of TiAl-based composites were mainly analyzed. The results showed that adding trace amount of nickel and aluminum could remarkably promote the sintering of gelcasting TiAl intermetallic samples, the micropores inside TiAl samples were connected after debinding, and the metallurgical structures were all intermetallic. After the porous TiAl samples impregnated with polycarbosilane were then pyrolyzed three times, the final metallurgical structures were TiAl-based composites of TiAl, NiAl, SiC, TiC and Ti3SiC2. Ti3SiC2 was the interface layer formed between TiAl intermetallic and SiC ceramic, and their high-temperature bending strength was between 82 MPa and 90 MPa at 1100 °C. Therefore, it was a promising method for the fabrication of complex high-performance TiAl-based parts such as turbine blade. © 2015 Published by Elsevier B.V. All rights reserved.
Lin K.,Northwestern Polytechnical University |
Yan H.,Collaborative Innovation Center for Advanced Aerospace Engine
Procedia Engineering | Year: 2015
The plasma actuator can make difference in changing the vortex characteristics in supersonic shear layer, leading to mixing enhancement and noise reduction in the supersonic shear layer. Large Eddy Simulation is performed to investigate the effect of plasma actuator on supersonic shear layer, in which the plasma actuator is simplified as heat source. A Mach 1.3 supersonic flow over a backward-facing step with a groove placed upstream of the step is simulated first. Then the plasma actuators are placed inside the groove, and the effect of the plasma actuator is studied. Results show that the cases with heat sources have larger growth of shear layer and area-Averaged vorticity compared with the baseline case, and increasing the amplitude of the actuation is a more efficient way for mixing enhancement. © 2015 The Authors.