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Aircraft engine fault detection based on grouped convolutional denoising autoencoders
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作者 Xuyun FU Hui LUO +1 位作者 Shisheng ZHONG Lin LIN 《中国航空学报:英文版》 SCIE EI CAS CSCD 2019年第2期296-307,共12页
Many existing aircraft engine fault detection methods are highly dependent on performance deviation data that are provided by the original equipment manufacturer. To improve the independent engine fault detection abil... Many existing aircraft engine fault detection methods are highly dependent on performance deviation data that are provided by the original equipment manufacturer. To improve the independent engine fault detection ability, Aircraft Communications Addressing and Reporting System(ACARS) data can be used. However, owing to the characteristics of high dimension, complex correlations between parameters, and large noise content, it is difficult for existing methods to detect faults effectively by using ACARS data. To solve this problem, a novel engine fault detection method based on original ACARS data is proposed. First, inspired by computer vision methods, all variables were divided into separated groups according to their correlations. Then, an improved convolutional denoising autoencoder was used to extract the features of each group. Finally, all of the extracted features were fused to form feature vectors. Thereby, fault samples could be identified based on these feature vectors. Experiments were conducted to validate the effectiveness and efficiency of our method and other competing methods by considering real ACARS data as the data source. The results reveal the good performance of our method with regard to comprehensive fault detection and robustness. Additionally, the computational and time costs of our method are shown to be relatively low. 展开更多
关键词 Aircraft engines ANOMALY DETECTION Convolutional NEURAL Network(CNN) DENOISING autoencoder Engine health management FAULT DETECTION
Robust decentralized control design for aircraft engines: A fractional type
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作者 Muxuan PAN Liangjin CAO +2 位作者 Wenxiang ZHOU Jinquan HUANG Ye-Hwa CHEN 《中国航空学报:英文版》 SCIE EI CAS CSCD 2019年第2期347-360,共14页
A new decentralized control for aircraft engines is proposed. In the proposed control approach, aircraft engines are considered as uncertain large-scale systems composed of interconnected uncertain subsystems. For eac... A new decentralized control for aircraft engines is proposed. In the proposed control approach, aircraft engines are considered as uncertain large-scale systems composed of interconnected uncertain subsystems. For each subsystem, the time-varying uncertainty, including parameter disturbances and interconnections in/between subsystems, is depicted by a class of general nonlinear functions. A fractional robust decentralized control with two parts, the nominal one and the fractional one, is presented. The nominal control guarantees the asymptotical stability of the engine system without uncertainty. The fractional part aims at overcoming the influences of uncertainty. Compared to the previous studies, the presented control provides not only an extra flexibility for the system performance tuning by the fraction-type gain but also a facility for the control input calculation. The proposed control approach is applied to a turbofan engine with two subsystems. The computer simulation shows that, in the flight envelope, the fractional control not only guarantees the closed-loop system uniform boundedness and ultimate uniform boundedness but also shows good economy. 展开更多
关键词 Aircraft engines LARGE-SCALE systems Robust DECENTRALIZED control Uncertainty UNIFORM BOUNDEDNESS UNIFORM ULTIMATE BOUNDEDNESS
Prospects of Reciprocating Engines and Fuels 预览
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作者 Michael J. Brear 《工程(英文)》 2019年第3期395-396,共2页
Reciprocating engines and their fuels are largely associated with road transport. This isn’t surprising. About 70% of transport-sector greenhouse gas emissions today are from road vehicles [1], and these vehicles are... Reciprocating engines and their fuels are largely associated with road transport. This isn’t surprising. About 70% of transport-sector greenhouse gas emissions today are from road vehicles [1], and these vehicles are overwhelmingly propelled by reciprocating engines. However, reciprocating engines are also widely used in other sectors, particularly off-road land transport, sea transport, and electrical power generation. 展开更多
关键词 Reciprocating Engines Fuels
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Fault diagnosis based on measurement reconstruction of HPT exit pressure for turbofan engine
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作者 Xin ZHOU Feng LU Jinquan HUANG 《中国航空学报:英文版》 SCIE EI CAS CSCD 2019年第5期1156-1170,共15页
Aero-engine gas path health monitoring plays a critical role in Engine Health Management(EHM). To achieve unbiased estimation, traditional filtering methods have strict requirements on measurement parameters which som... Aero-engine gas path health monitoring plays a critical role in Engine Health Management(EHM). To achieve unbiased estimation, traditional filtering methods have strict requirements on measurement parameters which sometimes cannot be measured in engineering. The most typical one is the High-Pressure Turbine(HPT) exit pressure, which is vital to distinguishing failure modes between different turbines. For the case of an abrupt failure occurring in a single turbine component, a model-based sensor measurement reconstruction method is proposed in this paper. First,to estimate the missing measurements, the forward algorithm and the backward algorithm are developed based on corresponding component models according to the failure hypotheses. Then,a new fault diagnosis logic is designed and the traditional nonlinear filter is improved by adding the measurement estimation module and the health parameter correction module, which uses the reconstructed measurement to complete the health parameters estimation. Simulation results show that the proposed method can well restore the desired measurement and the estimated measurement can be used in the turbofan engine gas path diagnosis. Compared with the diagnosis under the condition of missing sensors, this method can distinguish between different failure modes, quantify the variations of health parameters, and achieve good performance at multiple operating points in the flight envelope. 展开更多
关键词 Component-level model Condition monitoring FAULT diagnosis MEASUREMENT RECONSTRUCTION TURBOFAN engines Unscented KALMAN filter
Non-affine parameter dependent LPV model and LMI based adaptive control for turbofan engines
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作者 Bei YANG Xi WANG Penghui SUN 《中国航空学报:英文版》 SCIE EI CAS CSCD 2019年第3期585-594,共10页
The precise control of turbofan engines thrust is an important guarantee for an aircraft to obtain good flight performance and a challenge due to complex nonlinear dynamics of engines and time-varying parameters. The ... The precise control of turbofan engines thrust is an important guarantee for an aircraft to obtain good flight performance and a challenge due to complex nonlinear dynamics of engines and time-varying parameters. The main difficulties lie in the following two aspects. Firstly, it is hard to obtain an accurate kinetic model for the turbofan engine. Secondly, some model parameters often change in different flight conditions and states and even fluctuate sharply in some cases. These variable parameters bring huge challenge for the turbofan engine control. To solve the turbofan engine control problem, this paper presents a non-affine parameter-dependent Linear Parameter Varying(LPV) model-based adaptive control approach. In this approach, polynomial-based LPV modeling method is firstly employed to obtain the basis matrices, and then the Radial Basis Function Neural Networks(RBFNN) is introduced for the online estimation of the non-affine model parameters to improve the simulation performance. LPV model-based Linear Matrix Inequality(LMI) control method is applied to derive the control law. A robust control term is introduced to fix the estimation error of the nonlinear time-varying model parameters for better control performance. Finally, the Lyapunov stability analysis is performed to ensure the asymptotical convergence of the closed loop system. The simulation results show that the states of the engine can change smoothly and the thrust of the engine can accurately follow the desired trajectory, indicating that the proposed control approach is effective. The contribution of this work lies in the combination of linear system control and nonlinear system control methods to design an effective controller for the turbofan engine and to provide a new way for turbofan engine control research. 展开更多
关键词 Adaptive control LINEAR matrix INEQUALITIES LINEAR PARAMETER varying Neural networks TURBOFAN engines
Efficiency optimized fuel supply strategy of aircraft engine based on air-fuel ratio control
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作者 Yixuan WANG Yan SHI +2 位作者 Maolin CAI Weiqing XU Qihui YU 《中国航空学报:英文版》 SCIE EI CAS CSCD 2019年第2期489-498,共10页
Accurate fuel injection control of aircraft engine can optimize the energy efficiency of UAV power system while meeting the propeller speed requirement. Traditional injection control method such as open-loop calibrati... Accurate fuel injection control of aircraft engine can optimize the energy efficiency of UAV power system while meeting the propeller speed requirement. Traditional injection control method such as open-loop calibration causes instability of fuel supply which brings the risk of power loss of UAV. Considering that the closed-loop control of AFR can ensure a stable fuel feeding, this paper proposes an AFR control based fuel supply strategy in order to improve the efficiency of fuel-powered UAV while obtaining the required engine speed. According to the optimum fuel injection results, we implement fuzzy-PID method to control the set AFR in different situations. Through simulation and experiment studies, the results indicate that, to begin with, the calibrated mathematical model of the aircraft engine is effective. Next, this fuel supply strategy based on AFR control can normally realize the engine speed regulation, and the applied control algorithm can eliminate the overshoot of AFR throughout all the working progress. What is more,the fuel supply strategy can averagely shorten the response time of the engine speed by about two seconds. In addition, compared with the open-loop calibration, in this work the power efficiency is improved by 9% to 33%. Last but not the least, the endurance can be improved by 30 min with a normal engine speed. This paper can be a reference for the optimization of UAV aircraft engine. 展开更多
关键词 AFR control AIRCRAFT engines EFFICIENCY OPTIMIZATION FUEL supply STRATEGY Simulation and EXPERIMENTS
Development of Fuel/Engine Systems—The Way Forward to Sustainable Transport 预览
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作者 Gautam Kalghatgi 《工程(英文)》 2019年第3期510-518,共9页
The global demand for transport energy is large, growing, and primarily met by petroleum-derived liquid fuels powering internal combustion engines (ICEs). Moreover, the demand for jet fuel and diesel is projected to g... The global demand for transport energy is large, growing, and primarily met by petroleum-derived liquid fuels powering internal combustion engines (ICEs). Moreover, the demand for jet fuel and diesel is projected to grow faster than the demand for gasoline in the future, and is likely to result in low-octane gasoline components becoming more readily available. Significant initiatives with varying motivations are taking place to develop the battery electric vehicle (BEV) and the fuel cell as alternatives to ICE vehicles, and to establish fuels such as biofuels and natural gas as alternatives to conventional liquid fuels. However, each of these alternatives starts from a very low base and faces significant barriers to fast and unrestrained growth;thus, transport—and particularly commercial transport—will continue to be largely powered by ICEs running on petroleum-based liquid fuels for decades to come. Hence, the sustainability of transport in terms of affordability, energy security, and impact on greenhouse gas (GHG) emissions and air quality can only be ensured by improving ICEs. Indeed, ICEs will continue to improve while using current market fuels, through improvements in combustion, control, and after-treatment systems, assisted by partial electrification in the form of hybridization. However, there is even more scope for improvement through the development of fuel/engine systems that can additionally leverage benefits in fuels manufacture and use components that may be readily available. Gasoline compression ignition (GCI), which uses low-octane gasoline in a compression ignition engine, is one such example. GCI would enable diesel-like efficiencies while making it easier to control nitrogen oxides (NOx) and particulates at a lower cost compared with modern diesel engines. Octane on demand (OOD) also helps to ensure optimum use of available fuel anti-knock quality, and thus improves the overall efficiency of the system. 展开更多
关键词 Transport energy Internal COMBUSTION engines GASOLINE DIESEL
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电子技术在汽车发动机、底盘上的应用现状 预览
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作者 张帅 《科技视界》 2018年第31期52-53,共2页
本论文主要介绍了电子技术在汽车发动机、底盘方面的应用及发展趋势,指出电子技术已经渗入到汽车的各个部分,汽车正朝着更加智能、安全、环保的方向发展。
关键词 汽车 电子技术 应用 发动机 底盘
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汽车发动机常见故障与维修方法 预览 被引量:3
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作者 李全民 《现代制造技术与装备》 2018年第3期114-115,共2页
人们要分析研究汽车发动机的常见故障,并采取针对性措施进行处理。本文主要介绍了发动机常见的几种故障类型,提出相应的解决措施。
关键词 汽车 发动机 常见故障 维修方法
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发动机缸套温度无线测试技术研究 预览
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作者 蒋炎坤 陈永杰 +2 位作者 何书默 王浩 牛军 《湖北工业大学学报》 2018年第5期57-61,共5页
发动机传热问题一直是业内关注的热点之一,但当引线实时测试难于进行时,发动机温度热特性分析往往束手无策。为此,以柴油机缸套热特性分析为切入点,基于STM32单片机,研发一套发动机缸套温度无线测试系统。并进行相应的发动机台架... 发动机传热问题一直是业内关注的热点之一,但当引线实时测试难于进行时,发动机温度热特性分析往往束手无策。为此,以柴油机缸套热特性分析为切入点,基于STM32单片机,研发一套发动机缸套温度无线测试系统。并进行相应的发动机台架试验与验证。该无线温度测试系统具有采样频率和精度高、无线传输稳定等特点,同时具备有(引)线、无线传输和数据存储三种功能,并可作为终端具有实时显示功能。台架测试结果表明,实测值与仿真计算值吻合较好,各工况下误差均小于5%。 展开更多
关键词 发动机 温度测试 无线传输 单片机
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应变片用于斯特林发动机活塞位移的动态测量 预览 被引量:2
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作者 李薇 牟健 洪国同 《振动.测试与诊断》 EI CSCD 北大核心 2017年第2期372-376,共5页
结合自由活塞斯特林发动机的结构特点,提出了采用应变片响应板弹簧变形来动态测量活塞位移的方法。根据应变片的电阻应变效应与应变仪的电桥原理,建立了一套应变片测量位移的动态标定试验系统,将动态标定数据与静态标定数据进行了比较... 结合自由活塞斯特林发动机的结构特点,提出了采用应变片响应板弹簧变形来动态测量活塞位移的方法。根据应变片的电阻应变效应与应变仪的电桥原理,建立了一套应变片测量位移的动态标定试验系统,将动态标定数据与静态标定数据进行了比较分析。试验结果表明,应变片测量位移的方法存在一定的正反向、动静态差异,应变片的粘贴位置也会直接影响测量准确性。基于应变片传感器体积小,与板弹簧结合粘贴无需占用专门的空间,通过标定校准和合理的安装位置,仍然是一种较好的位移测量传感器。 展开更多
关键词 自由活塞斯特林发动机 动态位移测量 应变片 板弹簧
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Numerical Design and Performance Analysis of a Tug Boat Propulsion System 预览
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作者 Samson Nitonye Sidum Adumene Ukpokpo Umorami Howells 《电力能源(英文)》 2017年第11期80-98,共19页
The aim of this project is to design and analyze the propulsion system for a tugboat for optimum performance. In so doing, certain approved procedures were followed;these procedures included getting the desired tugboa... The aim of this project is to design and analyze the propulsion system for a tugboat for optimum performance. In so doing, certain approved procedures were followed;these procedures included getting the desired tugboat dimension, using ITTC methods, Gertlers charts, Bp charts etc. to estimate the bare hull resistance of the tugboat, estimating the effective power that must be employed to overcome this tug resistance. Numerical software code was developed to determine the various performance indicators of the propulsion system. The effective power was used as a basis for selecting the main engine and designing of a suitable propeller capable of propelling the tugboat for the various sea state were evaluated. Propeller cavitation was also put into consideration during this design. Hence in matching the engine to the propeller a series of calculations were done across a speed range of 300 - 500 rpm in other to effectively ascertain the engine-propeller matching point. The result shows that the point of engine-propeller matching is at 335 rpm and 2550 KW respectively. This provides a guide for the selection of a main engine with an acceptable sea service margins. All designs were done in accordance to classification organization and regulations. 展开更多
关键词 TUGBOAT PROPULSION System Engines RESISTANCE EFFECTIVE Power SPEED
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发动机冷却水套穴蚀机理分析与试验 预览 被引量:2
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作者 杜慧勇 周文瑾 +3 位作者 李民 刘建新 李鹏涛 徐斌 《农业工程学报》 CSCD 北大核心 2017年第8期76-81,共6页
为研究柴油机冷却水套内空化现象的产生机理,该文使用计算流体力学(CFD)方法研究施加壁面振动的不同入口流速、不同流场温度时冷却水套内部流体的流动特性及空化特性,同时设计并搭建可施加壁面振动的可视化空化试验台,对计算结果进行... 为研究柴油机冷却水套内空化现象的产生机理,该文使用计算流体力学(CFD)方法研究施加壁面振动的不同入口流速、不同流场温度时冷却水套内部流体的流动特性及空化特性,同时设计并搭建可施加壁面振动的可视化空化试验台,对计算结果进行了验证。研究结果表明:空化现象主要发生在圆弧壁最小间隙位置,并在下游区域发展壮大;冷却水入口流速的增加会使得空化现象略有加强,但并不明显;当冷却水温为50℃时,空化现象较强,当水温逐渐升高时,空化现象反而减弱;当圆弧壁面有振动时,空穴现象明显加强,并且其产生的空化效果明显强于冷却水温及入口流速等因素的变化所产生的空化波动。此研究的结果将有助于控制发动机冷却水套中空化现象的发生,并降低冷却水套穴蚀的发生风险。 展开更多
关键词 发动机 计算流体力学 试验 冷却水套 空化 穴蚀
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发动机配气机构传动系统的频率可靠性分析 预览
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作者 杨周 刘洋 张义民 《振动.测试与诊断》 EI CSCD 北大核心 2017年第2期284-287,共4页
根据发动机配气机构传动系统的固有频率与凸轮激振频率的差绝对值不超过规定槛值的关系准则,定义了配气机构传动系统共振的准失效状态,同时根据摄动理论和可靠性技术推导出参数为正态随机变量时的准失效概率表达式,提出了减小振动的可... 根据发动机配气机构传动系统的固有频率与凸轮激振频率的差绝对值不超过规定槛值的关系准则,定义了配气机构传动系统共振的准失效状态,同时根据摄动理论和可靠性技术推导出参数为正态随机变量时的准失效概率表达式,提出了减小振动的可靠性分析方法。在此基础上,以发动机配气机构振动简化模型为例,分别以所提方法和可靠性分析的Monte Carlo法计算该系统的共振可靠度,数值结果进一步证明了所提方法的可实用性。该方法可用于分析振动影响程度,以避免配气机构的共振失效。 展开更多
关键词 配气机构 振动与冲击 传动系统 频率分析 可靠度
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基于敏感IMF的再制造发动机振动状态研究 预览
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作者 陈成法 白云川 +2 位作者 张英锋 焦宇飞 李树珉 《振动.测试与诊断》 EI CSCD 北大核心 2017年第2期332-337,共6页
为了提高再制造发动机质量,将总体平均经验模态分解方法分解方法(ensemble empirical mode decomposition,简称EEMD)及敏感IMF选择算法引入再制造发动机性能研究中。在对再制造发动机非稳态振动信号进行EEMD分解的基础上,首先,将相关... 为了提高再制造发动机质量,将总体平均经验模态分解方法分解方法(ensemble empirical mode decomposition,简称EEMD)及敏感IMF选择算法引入再制造发动机性能研究中。在对再制造发动机非稳态振动信号进行EEMD分解的基础上,首先,将相关系数引入到IMF研究中,分析各IMF分量与原始信号的相关性,并计算原始信号各IMF分量的敏感因子;然后,利用敏感IMF进行Hilbert变换,并对再制造发动机的振动状态进行分析。研究结果表明,采用EEMD分解算法及敏感IMF的边际谱能反映再制造发动机不同部位的振动状态,缸壁、缸盖、曲轴三处对振动的敏感频率是存在差异的,通过对发动机各主要部位振动情况的研究,可以有针对性地采用再制造工艺,从而为提高发动机再制造水平提供技术支持。 展开更多
关键词 敏感IMF 振动状态 再制造发动机 边际谱
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Simulation of Automotive Engine Phase Signal Based on Closed-Loop Strategy 预览
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作者 Runlong Cui Mingfa Yao Tao Chen 《天津大学学报:英文版》 EI CAS 2017年第4期394-400,共7页
In this paper, an automotive engine phase signal simulation algorithm is proposed based on a closed-loop feedback strategy, and its corresponding model is built. The signal incentives are carried out in the front-end,... In this paper, an automotive engine phase signal simulation algorithm is proposed based on a closed-loop feedback strategy, and its corresponding model is built. The signal incentives are carried out in the front-end, and the synchronization capture and comparison are conducted in the back-end. The phase simulation of signal output is achieved using closed-loop strategy, which can effectively eliminate the inconsistency between crankshaft and camshaft phases, and thus the accuracy and flexibility of phase signal generation are guaranteed. Experimental results show that the proposed algorithm is real time, and the deviation of simulated signals from actual phase signals is small. 展开更多
关键词 CLOSED-LOOP CONTROL ENGINE electronic CONTROL unit SIGNAL SIMULATION SIGNAL CAPTURE
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冷起动两次喷油直喷汽油机的缸内可视化与排放 预览
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作者 宫艳峰 宋志平 +5 位作者 李显 张连方 窦慧莉 李华 夏春雨 于拓舟 《汽车安全与节能学报》 CAS CSCD 2017年第4期412-418,共7页
以可视化方法,试验研究了直喷(GDI)汽油机冷起动工况燃油两次喷射策略的污染物排放。采用光学单缸机和两台高速摄像机,同时从相互垂直的两个方向,记录燃油在气缸内的喷雾与燃烧过程,以燃烧分析仪分析燃烧稳定性,通过碳烟瞬态采集... 以可视化方法,试验研究了直喷(GDI)汽油机冷起动工况燃油两次喷射策略的污染物排放。采用光学单缸机和两台高速摄像机,同时从相互垂直的两个方向,记录燃油在气缸内的喷雾与燃烧过程,以燃烧分析仪分析燃烧稳定性,通过碳烟瞬态采集系统,分别用CLD500型和HFR500型火焰离子化检测仪(FID),对碳烟、NOx和HC进行记录分析。结果表明:在冷起动工况,第2次喷油正时过晚,燃油撞击活塞顶形成油膜,雾化不充分,会导致碳烟排放过高;第2次喷油正时提前,燃烧稳定性提高;增加第一次喷射的燃油质量比,可改善碳烟、NOx和HC排放,但略降低燃烧稳定性。 展开更多
关键词 汽油机 直喷(GDI) 冷起动 两次喷射 燃烧稳定性 可视化 污染物排放
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基于模糊神经网络的智能故障诊断专家系统 预览 被引量:24
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作者 司景萍 马继昌 +1 位作者 牛家骅 王二毛 《振动与冲击》 EI CSCD 北大核心 2017年第4期164-171,共8页
发动机是车辆的核心部件,及时有效地发现并排除故障,对降低维修费用,减少经济损失,增加发动机工作时的可靠性,避免事故发生具有重大的意义。以某型号发动机为研究对象,运用测试技术、信号处理、小波分析、神经网络和模糊控制理论,提出... 发动机是车辆的核心部件,及时有效地发现并排除故障,对降低维修费用,减少经济损失,增加发动机工作时的可靠性,避免事故发生具有重大的意义。以某型号发动机为研究对象,运用测试技术、信号处理、小波分析、神经网络和模糊控制理论,提出了基于模糊神经网络的智能故障诊断系统。建立了发动机故障信号采集试验台,在试验台上人工模拟3种转速下6种工况,通过加速度传感器采集正常工况和异常工况的振动信号,之后利用小波包技术进行消噪处理,并提取出故障信号的特征值,作为网络训练和测试的样本数据。用样本数据训练和检测自适应模糊神经网络,完成对信号的离线模式识别,之后以测试样本数据实现在线故障诊断,通过仿真分析,取得了很好的诊断效果。与传统的BP神经网络故障诊断方法进行对比,无论在诊断精度上还是学习速度上,模糊神经网络在故障诊断中更具有优势。同时,在专家系统的理论基础上,将模糊神经网络与专家系统进行信息融合,实现数据接口通信,利用网络的自学习能力建立智能故障诊断数据库和诊断规则库,通过程序语言快速高效的设计出智能诊断系统。最后,通过发动机故障诊断实例仿真分析,验证了基于模糊神经网络的智能故障诊断专家系统的可行性。 展开更多
关键词 神经网络 模糊理论 专家系统 小波分析 信息融合 智能故障诊断
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热声发电系统双功率优化运行阻抗匹配分析 被引量:2
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作者 何新 夏加宽 +1 位作者 李文瑞 张健 《中国电机工程学报》 EI CSCD 北大核心 2016年第19期5272-5278,5409共8页
为获得圆环体拓扑结构的热声发电系统最大电功输出,提出带有可变电负载的动磁式直线发电机声学阻抗匹配设计方法。通过声力电类比方法建立系统捕获声功和输出电功的数学模型。结合热声发动机机械结构和气体工作介质特征,分析弹簧机械阻... 为获得圆环体拓扑结构的热声发电系统最大电功输出,提出带有可变电负载的动磁式直线发电机声学阻抗匹配设计方法。通过声力电类比方法建立系统捕获声功和输出电功的数学模型。结合热声发动机机械结构和气体工作介质特征,分析弹簧机械阻抗和电负载阻抗对系统声学阻抗的影响,给出双功率优化运行的发电机声学阻抗匹配设计方法。该方法以提高声功捕获为约束条件,实现热声发电系统输出电功最大。用MATLAB程序和热声发电系统模拟实验平台验证双功率优化运行阻抗匹配方法。双功率优化运行的发电机声学阻抗匹配设计方法简单易行,为热声发电系统控制器的设计提供理论指导。 展开更多
关键词 分布式能源 热声发电系统 动磁式直线发电机 行波型热声发动机 阻抗匹配 双功率优化
微穿孔板抑制不稳定燃烧的声学数值仿真 被引量:1
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作者 初敏 徐旭 《声学学报》 EI CSCD 北大核心 2016年第2期236-242,共7页
为了研究微穿孔板吸声结构对不稳定燃烧的抑制作用,采用高精度的计算气动声学(ComputationalAeroacoustics,CAA)方法开展时域下的数值仿真。首先对带有压力时滞模型的三维声学扰动方程进行求解,给出发动机不稳定燃烧的频率信息。... 为了研究微穿孔板吸声结构对不稳定燃烧的抑制作用,采用高精度的计算气动声学(ComputationalAeroacoustics,CAA)方法开展时域下的数值仿真。首先对带有压力时滞模型的三维声学扰动方程进行求解,给出发动机不稳定燃烧的频率信息。然后通过解析模型分析微穿孔板吸声结构的阻抗特性,并由多自由度宽频阻抗模型模拟微穿孔板对该不稳定频率的抑制作用。仿真捕捉到的不稳定燃烧频率与地面试车测得的频率相一致。表明采用的计算气动声学方法及相应模型可以准确地捕捉不稳定燃烧的频率信息,并分析微穿孔板对不稳定燃烧的抑制作用,对于工程上快速预测不稳定燃烧具有一定意义。 展开更多
关键词 计算气动声学 不稳定燃烧 微穿孔板 数值仿真 稳定频率 抑制作用 吸声结构 时滞模型
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