基于块体单元离散模型的地铁车站爆炸破岩与防护研究

地铁已成为大、中型城市主要交通工具,然而地铁车站一直是恐怖爆炸袭击的重点对象,直接影响地铁运营安全,增强地铁车站结构防护抗爆能力至关重要.本文采用理论分析、数值模拟相结合的研究方法,利用单元内连续、单元间非连续的计算方法,构建块体单元离散弹簧动力学模型,建立地铁车站三维计算模型,模拟地铁车站内部爆炸状况,研究爆炸波空间传播和耗散规律及对构筑物破坏作用;分析低能爆炸作用下车站支柱混凝土、钢管护层混凝土和泡沫钢板夹芯护层混凝土抗爆性能,根据不同防护结构衰减应力波和吸能性能,优化地铁车站构筑物防护结构型式,提高车站抗爆能力,具有重要的实际应用价值

中空ねじ締結体の締結状態に及ぼすナット座面精度の影響 : 第1報, ナット座面精度と中空ボルトの軸方向ひずみ分布との関係

In order to accurately measure axial tension in bolted joint at the initial tightening and to evaluate the change in the axial tension in the joint, it is important to clarify the strain distribution of the cylindrical part tightened initially. As a first step, the effects of form accuracy of the nut bearing surface on tightening performance were investigated by FEM analysis and experiments. The obtained results were as follows. Peripheral strain distribution on the internal surface of hollow-type bolted joint is affected by the form accuracy of the nut bearing surface. The strain distribution depends on the height and number of asperities as a model of the height of summit and the number of waviness on the nut bearing surface. The trends of analytical results by FEM approximately agree with those of the experimental results. The effect of form accuracy on the range of strain distribution can be classified into three regions due to the height of asperities. It is found that as a guide for the design of bolted joints, the methods with FEM and with correlation coefficient are useful for the classification of the form accuracy

整合推動平台座談及發表會

[[note]]IAC-96-04

Optical diagnostics in a detonation-driven direct-connected circular combustor fueled with hydrogen for mach 10 scramjet

Various optical methods are applied to study flame characteristics of a circular -crosssection combustor for a Mach 10 scramjet. Experiments are performed on a direct connected test facility fueled by hydrogen and driven using hydrogen/oxygen detonation. The circular-cross-section combustor is advantageous in solving thermal in homogeneity, corner boundary layer and aircraft integration problems. However, it is difficult to use traditional optical measurement methods, which require large-sized measurement windows. In this study, tunable diode laser spectroscopy and a multi-view imaging system are used with small windows. High repetition rate measurements allow the effective time of facility, which is approximately 5 ms in this case, to be obtained. The dynamic flame characteristics are diagnosed upstream and downstream of the cavity with/ without strut injection. When combined with proper orthogonal decomposition to obtain the flame pulsation state during the effective time period, the method is expected to be effective for engine performance evaluation and numerical simulation verification. (c) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved

放射性核次级束流线终端实验装置的设计与结构

本文描述了一套放射性核次级束流引起反应测量的实验装置，它由次级束流鉴别、测量系统、次级靶控制系统和次级反应产物鉴别、测量系统组成。高增益分组延迟线读出、重心定位ＰＰＡＣ、横向场ＩＣ、椭球面镜聚焦、ＰＭＴ读出、闪烁薄膜时间拾取探测器、双叠层纵向场阳极分条读出ＩＣ、ＰＭＴ矩阵读出了Ｘ－Ｙ位置灵敏Ｐｈｏｓｗｉｃｈ闪烁探测器、康普顿抑制ＨＰＧｅγ探测器等单元是这套装置的基本部件

RIBLL1终端实验装置

描述了一套ＨＩＲＦＬ的放射性核次级束流引起反应测量的实验装置，它由ＲＩＢ鉴别、测量系统、次级靶控制系统和次级反应产物鉴别、测量系统组成．高增益分组延迟线读出、重心定位ＰＰＡＣ，横向场ＩＣ，椭球面镜聚焦、ＰＭＴ读出、闪烁薄膜时间拾取器，双叠层纵向场阳极分条读出ＩＣ，ＰＭＴ矩阵读出ｘ—ｙ位置灵敏Ｐｈｏｓｗｉｃｈ闪烁探测器，康普顿抑制ＨｐＧｅγ探测器等单元是这套装置的基本部件．目前，该装置已安装在兰州重离子加速器ＲＩＢＬＬ１终端．性能测试和实验研究正在进行．RIBLL1 experimental setup consists of RIB identification system,secondary target control system and secondary reaction products measurement system.The high gain x-y position sensitive PPAC with delay cable grouped readout,the scintillation foil time pickup detector focusing with ellipsoidal surface,the traverse field IC,the large area two dimensional position sensitive scintillatillator with PMT matrix readout,the Compton suppressed HPGe γ-ray detectors and twin longitudinal field iC are major components.Th..