Predicting the Performance Deterioration of a Three-Shaft Industrial Gas Turbine

The gas turbine was one of the most important technological developments of the early 20th century, and it has had a significant impact on our lives. Although some researchers have worked on predicting the performance of three-shaft gas turbines, the effects of the deteriorated components on other primary components and of the physical faults on the component measurement parameters when considering the variable inlet guide valve scheduling and secondary air system for three-shaft gas turbine engines have remained unexplored. In this paper, design point and off-design performance models for a three-shaft gas turbine were developed and validated using the GasTurb 13 commercial software. Since the input data were limited, some engineering judgment and optimization processes were applied. Later, the developed models were validated using the engine manufacturer’s data. Right after the validation, using the component health parameters, the physical faults were implanted into the non-linear steady-state model to investigate the performance of the gas turbine during deterioration conditions. The effects of common faults, namely fouling and erosion in primary components of the case study engine, were simulated during full-load operation. The fault simulation results demonstrated that as the severity of the fault increases, the component performance parameters and measurement parameters deviated linearly from the clean state. Furthermore, the sensitivity of the measurement parameters to the fault location and type were discussed, and as a result they can be used to determine the location and kind of fault during the development of a diagnosis model.     

Implementation of Fault-Tolerant Encoding Circuit Based on Stabilizer Implementation and “Flag” Bits in Steane Code

Quantum error correction (QEC) is an effective way to overcome quantum noise and de-coherence, meanwhile the fault tolerance of the encoding circuit, syndrome measurement circuit, and logical gate realization circuit must be ensured so as to achieve reliable quantum computing. Steane code is one of the most famous codes, proposed in 1996, however, the classical encoding circuit based on stabilizer implementation is not fault-tolerant. In this paper, we propose a method to design a fault-tolerant encoding circuit for Calderbank-Shor-Steane (CSS) code based on stabilizer implementation and “flag” bits. We use the Steane code as an example to depict in detail the fault-tolerant encoding circuit design process including the logical operation implementation, the stabilizer implementation, and the “flag” qubits design. The simulation results show that assuming only one quantum gate will be wrong with a certain probability p, the classical encoding circuit will have logic errors proportional to p; our proposed circuit is fault-tolerant as with the help of the “flag” bits, all types of errors in the encoding process can be accurately and uniquely determined, the errors can be fixed. If all the gates will be wrong with a certain probability p, which is the actual situation, the proposed encoding circuit will also be wrong with a certain probability, but its error rate has been reduced greatly from p to p2 compared with the original circuit. This encoding circuit design process can be extended to other CSS codes to improve the correctness of the encoding circuit.     

空间摄像机的热设计

根据空间摄像机的所处空间环境和结构特点,对其进行了热设计.采用被动热控措施进行热隔离和热疏导,充分利用了摄像机所搭载的卫星平台的热容;采用主动热控措施进行温差补偿,将温度拉平至热控指标范围之内.根据所采用的热控措施,针对空间摄像机进行了仿真分析,得到了满意的结果.     

木卫停泊轨道间低耗能小推力转移轨道设计方法研究

对木卫停泊轨道间的低耗能小推力转移轨道设计方法进行了研究,提出基于“类halo轨道截面”法的低耗能转移轨道参数化方法和基于配点法的多体Lambert问题求解算法,并利用全局优化算法得出了燃耗最少的初步优化结果;利用多体同伦法和固定近心点高度的多圈转移控制律得到了各段小推力转移轨道的有效设计结果.所提方法同样适用于其他天体间的转移轨道设计,为多体环境下低耗能小推力转移轨道提出了新的设计思路和方法.     

固定需求下基于概率型随机平衡的交通网络设计模型及算法

在考虑网络中用户的路径选择行为满足概率型随机平衡的条件下,给出了交通网络设计的双层规划模型,同时设计了基于差分的启发式求解算法．     

高铁座椅靠背压坏笔记本显示屏谁之过

乘坐高铁时,时有发生在小桌板上使用笔记本电脑时被前排座椅靠背压坏的事故,给双方乘客均造成了不必要的经济损失。本文首先介绍了一起发生在2022年3月4日的典型案例,然后利用力学理论分析了小桌板上笔记本显示屏被压破坏的原因,最后给出了高铁座椅和小桌板的优化设计建议,为避免类似事故再次发生提供了重要的借鉴。

     

基于BESO算法的涡轮盘拓扑优化

涡轮盘作为航空发动机的核心部件之一,其轻量化设计对航空发动机效率提升至关重要。基于双向渐进结构优化算法（bidirectional evolutionary structural optimization, BESO）拓扑优化模型,使用灵敏度过滤的方法抑制棋盘格现象,用ANSYS的参数化设计语言（ANSYS parametric design language, APDL）编写拓扑优化程序,对离心载荷作用下的涡轮盘进行结构优化,并通过施加叶片等效载荷的方式,考虑叶片对于优化结果的影响。结果表明,使用编写的算法进行拓扑优化迭代步数减少,显著提升优化效率,在减重26%的条件下,拓扑出的新的结构模型结构总应变能降低48%,结构刚度提升,最大等效应力降低25%且应变能和应力分布更均匀合理。

     

Development of a Protein-Rich By-Product by 23 Factorial Design: Characterization of Its Nutritional Value and Sensory Analysis

The aim of this study was the development of a cereal bar based on bee pollen (BP), honey (H), and flour by-products (peel passion fruit flour—PPFF), generating an innovative product. BP is a protein-rich ingredient and can be used in the composition of cereal bars. PPFF is a by-product rich in fibers. The formulations were developed using a 2³ factorial design with four replicates in the center point, studying the sensory analysis as a response variable. The texture and nutritional parameters were performed for the optimal formulation. BP showed ca. 15% of protein. The final formulation (10.35% BP, 6.8% PPFF, and 25% H) presented 22.2% moisture, 1.8% ash, 0.4% total fat, 3.0% fiber, 63.1% carbohydrates, and 74.0 Kcal/25 g. The sensory analysis presented valued around 7 (typical of a traditional bar). Regarding the possibility of purchasing the product, 51% of the panelists said they would probably buy the developed product. The formulated cereal bar had a similar composition as those already marketed. Moreover, it can be considered a source of fiber and is sensory acceptable. This approach opens up new opportunities for developing nutritional and functional foodstuff with improved sensorial aspects.     

风筝设计及其在航空教育实践中的应用

为了使风筝能够更好地在青少年航空教育教学实践中得到推广,本文阐述了风筝构造、空气动力,以及受力与稳定性分析等风筝设计的相关概念与原理,介绍了美国NASA航空教育的风筝设计软件Kite Modeler,以及自己的教育教学实践情况。实践表明,风筝设计、制作、放飞是一项集简易航空器设计、手工制作、体能锻炼、休闲娱乐等为一体的实践活动,在大中小学航空教育中具有良好的现实意义。     

夹层式光纤激光水听器探头优化设计

为改善分布反馈式(DFB)光纤激光器水声探测性能,利用有限元软件ANSYS,以相对加速度灵敏度为目标函数,结构尺寸参数为设计变量,结构第一阶固有频率和探头声压灵敏度为状态变量,对夹层式封装结构进行了优化设计,对其声压探测及抗加速度机理进行了分析。分析表明,基于优化结果设计的探头在采用100 m非平衡干涉仪时,其声压灵敏度约为-135.1 dB,相对加速度灵敏度可达到-19.6 dB。结果表明,基于封装结构敏感部分分别承受声压激励和加速度激励时的不同响应机理,对夹层式封装结构关键部位尺寸进行优化设计后,通过合理选择承压梁与中间变形梁的厚度以及上下连接点的位置,封装制得的光纤激光水听器具有较高的声压灵敏度和良好的抗加速度性能。