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Effect of dilution holes on the performance of a triple swirler combustor

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Chinese Journal of Aeronautics 2014年第6期27卷 1421-1429页

作者： Ding Guoyu He Xiaomin Zhao Ziqiang An Bokun Song Yaoyu Zhu Yixiao Jiangsu Province Key Laboratory of Aerospace Power Systems College of Energy and Power Engineering Nanjing University of Aeronautics and Astronautics Co-Innovation Center for Advanced Aero-engine AVIC Harbin dongan engine (group) Corporation Ltd.

A triple swirler combustor is considered to be a promising solution for future high temperature rise combustors. The present paper aims to study dilution holes including primary dilution holes and secondary dilution holes on the performance of a triple swirler combustor. Experimental investigations are conducted at different inlet airflow velocities（40–70 m/s） and combustor overall fuel–air ratio with fixed inlet airflow temperature（473 K） and atmospheric pressure. The experimental results show that the ignition is very difficult with specific performance of high ignition fuel–air ratio when the primary dilution holes are located 0.6H（where H is the liner dome height）downstream the dome, while the other four cases have almost the same ignition performance. The position of primary dilution holes has an effect on lean blowout stability and has a large influence on combustion efficiency. The combustion efficiency is the highest when the primary dilution holes are placed 0.9H downstream the dome among the five different *** the secondary dilution holes, the pattern factor of Design A is better than that of Design B.

关键词： Combustor performance Fuel–air ratio Primary dilution holes Secondary dilution holes Triple swirler combustor

Protective behavior of an SO_2/CO_2 gas mixture for molten AZ91D alloy

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China Foundry 2012年第3期9卷 226-230页

作者： Liang Weizhong Gao Qiu Chen Fu Liu Honghui Zhao Zhenhua Department of Materials Science&engineering Heilongjiang Institute of Science and Technology Harbin 150027China Harbin dongan engine(group)Company Limited Harbin 150066China

The protective behavior for a molten AZ91D alloy in an open melting furnace was investigated under a protective gas mixture containing 3% SO2 and 97% CO2, and the protection mechanism was discussed. Experimental results show that the gas mixture provides effective protection for AZ91D melt in the temperature range from 680 ℃ to 730 ℃. The microstructure, chemical composition and phase composition of the surface film formed on the molten AZ91D alloy were analyzed using scanning electron microscopy （SEM） with energy dispersive spectrometer （EDS） and X-ray diffraction （XRD）. The SEM results demonstrate that the surface films with an average thickness between 0.5 pm and 2 pm are dense and coherent in the protected temperature range. The EDS results reveal that the surface film mainly contains elements S, C, O, AI and Mg. The XRD results show that the surface film consists of MgO, MgS and a small amount of C phase.

关键词： AZ91D alloy protective behavior SO2/CO2 gas mixture surface film

Partition method for improvement of piecewise linear model with full envelope covered

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航空动力学报 2016年第12期31卷 3042-3053页

作者： YANG Shu-bo WANG Xi LONG Yi-fu LI Zhi-peng HU Zhong-zhi YIN Kai ZHANG Rong School of Energy and Power engineering Beijing University of Aeronautics and Astronautics Commercial Aircraft engine Company Limited Aero Engine(Group)Corporation of China

Since ambient conditions vary in a wide range within the full flight envelope,the existing piecewise linear model(PLM),which is based on sea-level static condition with use of corrected parameters for other points in the flight envelope,cannot meet the accuracy for replacing the nonlinear *** obtain more accurate linear models,a method of partitioning the flight envelope over a grid of Mach number and altitude boxes was ***,a set of linear models for a given operating condition was selected by picking the nearest(Mach number,altitude)box in the flight *** the selected set of linear models,interpolating for power level based on a weighted sum of corrected rotor speeds can obtain a linear model with acceptable *** results of different points within the full flight envelope showed that the maximum error between nonlinear model and the existing PLM was more than 50%,while the maximum error between nonlinear model and the improved PLM was within 8%.It is concluded that the improved PLM performs accurately,especially under the non-standard *** addition,the improved PLM can satisfy the real-time requirement better than the existing PLM.

关键词： piecewise linear model partition full envelope parameter schedule turbofan engine

Review of Numerical Simulation of TGO Growth in Thermal Barrier Coatings

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Computer Modeling in engineering & Sciences 2022年第8期132卷 361-391页

作者： Quan Wen Fulei Jing Changxian Zhang Shibai Tang Junjie Yang Aero engine Academy of China Aero Engine(Group)Corporation of ChinaBeijing101304China Institute for Aero engine Tsinghua UniversityBeijing100084China

Thermally grown oxide(TGO)is a critical factor for the service life of thermal barrier coatings(TBC).Numerical simulations of the growth process of TGO have become an effective means of comprehensively understanding the progressive damage of the TBC *** present,technologies of numerical simulation to TGO growth include two categories:coupled chemical-mechanical methods and mechanical equivalent *** former is based on the diffusion analysis of oxidizing elements,which can describe the influence of bond coat(BC)consumption and phase transformation in the growth process of TGO on the mechanical behavior of each layer of TBC,and has high accuracy for the thickness evolution of TGO,but they cannot describe the lateral growth of TGO and the rumpling phenomenon *** latter focuses on describing the final stress and strain state after the growth of a specific TGO rather than the complete growth processes of *** on the measured TGO thickness growth curve,simulations of thickening and lateral growth can be achieved by directly applying anisotropic volumetric strain to oxidized elements and switching elements properties from the BC to the TGO.

关键词： Thermal grown oxide(TGO) numerical simulation thermal barriers coatings(TBC) finite element method lateral growth

Vacuum carburization of 12Cr2Ni4A low carbon alloy steel with lanthanum and cerium ion implantation

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Journal of Rare Earths 2017年第11期35卷 1164-1170页

作者： Meiling Dong Xiufang Cui Yuhui Zhang Guo Jin Caiwen Yue Xin Zhao Zhaobing Cai Binshi Xu Institute of Surface/Interface Science and Technology Key Laboratory of Superlight Material and Surface Technology of Ministry of Education HarbinEngineering University Harbin 150001 China College of Materials Science and Chemical engineering Harbin Engineering University Harbin 150001 China dongan engine group Harbin 150060 China

As bearing parts, 12 Cr2 Ni4 A is expected to have high hardness and excellent fatigue strength, so carburizing is employed to improve the inherit properties of 12 Cr2 Ni4 A. However, the traditional carburizing is limited by poor microstructure distribution and low rate of carburizing. The rare earth ion implantation is known to help improving the properties of tribology, corrosion resistance and oxidation resistance of metal. In this article, the RE implantation is employed to assist the carburizing. Lanthanum and cerium ion implantations are initially used to assist 12 Cr2 Ni4 A low pressure vacuum *** microstructure, content of retained austenite, hardness, thickness of layer and carbon diffusion were analyzed by optical microscopy(OM), scanning electron microscopy(SEM), X-ray diffraction(XRD) and Rockwell/Vickers hardness tester, respectively. It was shown that lanthanum and cerium implantations can improve structure of the vacuum carburizing layer, and enhance the uniformity of carbon element distribution on the carburized surface. Meanwhile the RE implantation plays a positive role in promoting the surface hardness and carburized rate. The lanthanum element has more significant effect on surface hardness and content of retained austenite than cerium element. The surface hardness of lanthanum element implanted layer was 62.9 HRC with 9.6% content of retained austenite, while the carburizing rate of cerium implanted layer increased by 12.4%.

关键词： Vacuum carburization Ion implantation Lanthanum Cerium Diffusion

Large eddy simulation of turbulent premixed and stratified combustion using flame surface density model coupled with tabulation method

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Applied Mathematics and Mechanics(English Edition) 2018年第12期39卷 1719-1736页

作者： Zhou YU Hongda ZHANG Taohong YE Minming ZHU Department of Thermal Science and Energy engineering University of Science and Technology of China Shenyang engine Research Institute Aero Engine (Group) Corporation of China

Large eddy simulations(LESs) are performed to investigate the Cambridge premixed and stratified flames, SwB1 and SwB5, respectively. The flame surface density(FSD) model incorporated with two different wrinkling factor models, i.e., the Muppala and Charlette2 wrinkling factor models, is used to describe combustion/turbulence interaction, and the flamelet generated manifolds(FGM) method is employed to determine major scalars. This coupled sub-grid scale(SGS) combustion model is named as the FSD-FGM model. The FGM method can provide the detailed species in the flame which cannot be obtained from the origin FSD model. The LES results show that the FSD-FGM model has the ability of describing flame propagation, especially for stratified flames. The Charlette2 wrinkling factor model performs better than the Muppala wrinkling factor model in predicting the flame surface area change by the *** combustion characteristics are analyzed in detail by the flame index and probability distributions of the equivalence ratio and the orientation angle, which confirms that for the investigated stratified flame, the dominant combustion modes in the upstream and downstream regions are the premixed mode and the back-supported mode, respectively.

关键词： large eddy simulation(LES) flame surface density(FSD) model tabulation premixed combustion stratified combustion

Large eddy simulation of turbulent premixed piloted flame using artificial thickened flame model coupled with tabulated chemistry

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Applied Mathematics and Mechanics(English Edition) 2018年第9期39卷 1277-1294页

A sub-grid scale(SGS) combustion model, which combines the artificial thickened flame(ATF) model with the flamelet generated manifold(FGM) tabulation method, is proposed. Based on the analysis of laminar flame structures, two self-contained flame sensors are used to track the diffusion and reaction processes with different spatial scales in the flame front, respectively. The dynamic formulation for the proposed SGS combustion model is also performed. Large eddy simulations(LESs) of Bunsen flame F3 are used to evaluate the different SGS combustion models. The results show that the proposed SGS model has the ability in predicting the distributions of temperature and velocity reasonably, while the predictions for the distributions of some species need further improvement. The snapshots of instantaneous normalized progress variables reveal that the flame is more remarkably and severely wrinkled at the flame tip for flame *** satisfactory results obtained by the dynamic model indicate that it can preserve the premixed flame propagation characteristics better.

关键词： large eddy simulation(LES) artificial thickened flame model tabulation dynamic modeling flame sensor

Establishment of a CouplingModel for the Prediction of Heat Dissipation of the Internal Combustion engine Based on Finite Element

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Energy engineering 2022年第3期119卷 1103-1116页

作者： Hongyu Mu Yinyan Wang Hong Teng Xingtian Zhao Xiaolong Zhang Yan Jin Shiyang Hao Jingfeng Zhao College of Power and Energy engineering Harbin Engineering UniversityHarbin150001China engine Department R&D CenterHarbin Dongan Auto Engine Co.Ltd.Harbin150066China

The aerodynamics and heat transfer performance in the rear-mounted automobile cabin have an important influence on the engine’s safety and the operational stability of the *** article uses STARCCM and GT-COOL software to establish the 3D wind tunnel model and engine cooling system model of the internal combustion *** the same time,we established a 3D artificial coupling model through parameter *** research results show that the heat transfer coefficient decreases with the increase of the comprehensive drag coefficient of the *** shows that the cabin flow field has an important influence on the heat transfer *** temperature rise of the engine room increases with the increase of the engine *** is proved that vehicle speed affects the amount of heat dissipation of the engine room internal combustion engine under certain load *** article provides a more effective and fast calculation method for the research on the heat dissipation of the internal combustion engine and the optimization of the cooling system equipment.

关键词： Internal combustion engine coupled model prediction heat dissipation heat dissipation of the whole machine

Stress-controlled LCF experiments and ratcheting behaviour simulation of a nickel-based single crystal superalloy with [001] orientation

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Chinese Journal of Aeronautics 2021年第8期34卷 112-121页

作者： Bin ZHANG Rongqiao WANG Dianyin HU Kanghe JIANG Jianxing MAO Fulei JING Xinyi HAO School of Energy Power EngineeringBeihang UniversityBeijing 100083China Beijing Key Laboratory of Aero-engine Structure and Strength Beijing 100083China Research Institute of Aero-engine Beihang UniversityBeijing 100083China Hunan Aviation Powerplant Research Institute Aero Engine(Group)Corporation of ChinaZhuzhou 412002China Aero engine Academy of China Aero Engine(Group)Corporation of ChinaBeijing 101304China

Uniaxial ratcheting behaviour and low cycle fatigue(LCF)failure mechanism of nickel-based single crystal superalloy DD6 with[001]orientation are investigated through the stresscontrolled LCF tests with stress ratio *** the deformation behaviour during the wholelifetime from the beginning of the experiment to the fracture of the specimen,as well as the fractographic/metallographic morphology,are compared with the strain-controlled LCF experimental *** the scanning electron microscope(SEM)observations,it is shown that the failure characteristics under stress-controlled LCF loading are similar with those under strain-controlled ***,unlike strain-controlled LCF loading,even under fully reversed cycle loading for stress-controlled LCF,DD6 shows significant ratcheting behaviour due to the tensioncompression *** addition,the LCF lifetimes under stress control are significantly shorter than the LCF lifetimes under strain control,and the culprit might be the detrimental effect of ratcheting strain on LCF *** on these phenomena,an improved crystal plasticity constitutive model on the basis of slip-based Walker constitutive model is developed through modifying the kinematic hardening rule in order to overcome the inaccurate prediction of decelerating stageand stable stage of ratcheting ***,combining the continuum damage mechanics,a damage-coupled crystal plasticity constitutive model is proposed to reflect the damage behaviour of DD6 and the accelerating stage of ratcheting *** simulation results for the stress-controlled LCF deformation behaviour including the whole-lifetime ratcheting behaviour show good agreement with the experimental data.

关键词： Crystal plasticity constitutive model Low cycle fatigue Nickel-based single crystal superalloy Ratcheting behaviour Stress-controlled experiment