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亚声速段横向射流对coil性能影响的数值研究

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计算物理 2008年第4期25卷 414-420页

作者：吕俊明胡宗民姜宗林高温气体动力学重点实验室中国科学院力学研究所北京100190

在化学氧碘激光的混合喷管内发生的是一个气体动力学、化学反应动力学以及光学等相互耦合的复杂过程,每个过程都对coil性能有着至关重要的影响.利用三维CFD技术,通过求解层流Navier-Stokes方程与组分输运方程,对简化后的化学氧碘激光RAD... 详细信息

在化学氧碘激光的混合喷管内发生的是一个气体动力学、化学反应动力学以及光学等相互耦合的复杂过程,每个过程都对coil性能有着至关重要的影响.利用三维CFD技术,通过求解层流Navier-Stokes方程与组分输运方程,对简化后的化学氧碘激光RADICL模型进行数值模拟与分析,对coil的气动和增益特性进行探讨.在不同的射流穿透条件下,计算coil混合喷管中的混合与化学反应过程,发现穿透深度决定了增益的分布特性以及过度穿透条件下的非定常结构.

关键词： coil 横向射流穿透增益非定常结构总压恢复

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流量配比对coil增益分布影响的数值研究

计算物理 2009年第4期26卷 541-547页

作者：吕俊明王春姜宗林 LHD 中国科学院力学研究所北京100080

利用三维CFD技术,通过求解层流Navier-Stokes方程与组分输运方程,对简化后的化学氧碘激光RADICL模型进行数值模拟与分析,结合10种组分和21个基元反应的化学反应模型,对coil亚声速段横向射流情况下,不同的主副流流量配比对化学氧碘激光... 详细信息

利用三维CFD技术,通过求解层流Navier-Stokes方程与组分输运方程,对简化后的化学氧碘激光RADICL模型进行数值模拟与分析,结合10种组分和21个基元反应的化学反应模型,对coil亚声速段横向射流情况下,不同的主副流流量配比对化学氧碘激光器性能的影响进行分析与比较.结果证明,过高或过低的碘分子浓度状态均不利于合理、可观的小信号增益系数产生.存在一个最佳流量配比范围,与之对应的工作状态下,coil的小信号增益系数会得到显著提高.

关键词： coil 横向射流流量配比增益系数

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以氮气为载气coil的设计与实验

强激光与粒子束 2003年第12期15卷 1148-1150页

作者：房本杰桑凤亭陈方张岳龙金玉奇李庆伟中国科学院大连化学物理研究所辽宁大连116023

　根据以氮气为载气的特殊要求,对kW级氧碘化学激光器(coil)装置的结构进行了有针对性的设计和实验研究。在氯气流量为140mmol/s的情况下,获得了2.6kW的功率,相应的化学效率为20.4%,喷管出口能流密度达到了74W/cm2。这一结果达到了以氦... 详细信息

　根据以氮气为载气的特殊要求,对kW级氧碘化学激光器(coil)装置的结构进行了有针对性的设计和实验研究。在氯气流量为140mmol/s的情况下,获得了2.6kW的功率,相应的化学效率为20.4%,喷管出口能流密度达到了74W/cm2。这一结果达到了以氦气为载气coil的水平。

关键词： coil 氮气功率化学效率喷管能流密度

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竖直隔板对coil超扩段流场影响实验研究

强激光与粒子束 2003年第8期15卷 729-732页

作者：蔡光明刘军宋影松王永振中国工程物理研究院应用电子学研究所四川绵阳621900

　通过一系列对比实验比较了隔板对气流转捩点、总压损失、光腔静压的影响,并通过分析阐述了竖直隔板对扩压器内部气流参数产生影响的原因。隔板可以增加超音速区域的长度,并能增加光腔压力分布的稳定性,减小总压损失,增加压力恢复系数... 详细信息

　通过一系列对比实验比较了隔板对气流转捩点、总压损失、光腔静压的影响,并通过分析阐述了竖直隔板对扩压器内部气流参数产生影响的原因。隔板可以增加超音速区域的长度,并能增加光腔压力分布的稳定性,减小总压损失,增加压力恢复系数;隔板厚度对光腔静压的影响较大,需严格控制隔板厚度以避免正激波的产生。

关键词： coil 扩压器隔板

以氮气为载气的千瓦级coil的初步实验研究

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强激光与粒子束 2002年第3期14卷 447-450页

作者：房本杰陈方张岳龙金玉奇桑凤亭中国科学院大连化学物理研究所辽宁大连116023

首次在氯气流量为 110 mmol/ s、采用方列管型射流式 O2 (1 Δ)发生器 (SPJSOG)以及列阵式超音速氧碘混合喷管的 coil装置上 ,以氮气替代氦气作为载气进行出光实验研究。初步实验获得 1.8k W的激光输出功率以及

关键词： coil SPJSOG 氮气激光输出功率化学效率国际氧碘化学激光激光器

Numerical simulation and experiment of error field measurement using luminous trace of electron beam in SST-1

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Plasma Science and Technology 2019年第10期21卷 9-16页

作者： Someswar DUTTA Y PARAVASTU J DHONGDE H CHUDASMA S GEORGE K DHANANI A MAKWANA C DODIYA P VARMORA D K SHARMA A K SINGH U KUMAR D RAVAL U PRASAD Z KHAN R SRINIVASAN D RAJU Institute for Plasma Research GandhinagarGujrat 382428India Homi Bhabha National Institute (HBNI) AnushaktinagarMumbai 400094India

In contrast to the earlier experiments conducted in other machines, here, in SST-1 the error field measurement experiment is performed with a filled gas pressure ~8×10^-4 mbar which helped to create a luminescent toroidal beam of electron path originated due to impact excitation and guided by the toroidal magnetic field. Beam path deviations are observed and recorded from radial and top ports using visible range cameras. Such creation and detection of the electron beam path differs from the earlier works where the gun emitted electron beam deviation in ultrahigh vacuum was detected on a collector-grid/fluorescent screen. In the present experiment, large beam deviations were observed. Later investigation of the experimental set-up reveals existence of a possible source of radial electric field in between the source and the vacuum vessel which are separately grounded. Thus, to understand the observed phenomena, experiments are numerically modeled with deviated TF coil set, PF coil set and the electron source location. A particle tracing code is used to follow the electron path in the magnetic field generated by the coil set of interest. Simulation results suggest that the large deviation corresponds to the E×B drifts and not due to the large field errors. Toroidally averaged field errors of the SST-1 TF coils at toroidal field of B0?=?15 kG are negligibly small ~B0?×?10^-6 or less, which should not adversely affect the plasma performance.

关键词： electron beam error field SST-1 TF coil

A 4-channel 3 Tesla phased array receive coil for awake rhesus monkey fMRI and diffusion MRI experiments

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Journal of Biomedical Science and Engineering 2010年第11期3卷 1085-1092页

作者： Mark Haig Khachaturian Athinoula A. Martinos Center for Biomedical Imaging Massachusetts General Hospital Harvard Medical School Charlestown USA.

Awake monkey fMRI and diffusion MRI combined with conventional neuroscience techniques has the potential to study the structural and functional neural network. The majority of monkey fMRI and diffusion MRI experiments are performed with single coils which suffer from severe EPI distortions which limit resolution. By constructing phased array coils for monkey MRI studies, gains in SNR and anatomical accuracy (i.e., reduction of EPI distortions) can be achieved using parallel imaging. The major challenges associated with constructing phased array coils for monkeys are the variation in head size and space constraints. Here, we apply phased array technology to a 4-channel phased array coil capable of improving the resolution and image quality of full brain awake monkey fMRI and diffusion MRI experiments. The phased array coil is that can adapt to different rhesus monkey head sizes (ages 4-8) and fits in the limited space provided by monkey stereotactic equipment and provides SNR gains in primary visual cortex and anatomical accuracy in conjunction with parallel imaging and improves resolution in fMRI experiments by a factor of 2 (1.25 mm to 1.0 mm isotropic) and diffusion MRI experiments by a factor of 4 (1.5 mm to 0.9 mm isotropic).

关键词： 4-Channel fMRI RF coil Design Monkey SNR G-Factor Diffusion MRI Phased Array

VICON程序模拟氧碘化学激光器3维喷管流场的可行性探讨

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强激光与粒子束 2006年第5期18卷 736-740页

作者：李艳李守先余真北京应用物理与计算数学研究所北京100088

用VICON程序对化学氧碘激光器(coil)喷管冷流场进行了3维模拟,得出的计算区几何较准确地反映了模拟装置的几何变化。主气流方向和副气流方向的分点数反映出了此2维平面内的气动特性,对不同流量的模拟结果对比分析得出穿透过度与穿透不... 详细信息

用VICON程序对化学氧碘激光器(coil)喷管冷流场进行了3维模拟,得出的计算区几何较准确地反映了模拟装置的几何变化。主气流方向和副气流方向的分点数反映出了此2维平面内的气动特性,对不同流量的模拟结果对比分析得出穿透过度与穿透不够一样,致使主副气流混合不好。对带化学反应的情况进行了模拟,显现出副气流从喷孔出来后穿进主气流的马蹄形结构的变化过程,这些说明VICON程序可用来模拟研究coil喷管流场特性。

关键词： VICON程序 3维喷管 coil 网格点数数值模拟

Precise localization of small pulmonary nodules using Pre-VATS with Xper-CT in combination with real-time fluoroscopy-guided coil:report of 15 patients

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Journal of Interventional Medicine 2018年第2期1卷 102-105页

作者： Jiemin Cheng Changyu Li Liangwen Wang Jiting Liang Zhiping Yan Jiani Hu Huibing Shi Department of Interventional Radiology Shanghai Zhongshan Hospital Fudan University Shanghai Medical Image Institute

Purpose: This study aimed to evaluate the value of precise localization of nodules using pre-video-assisted thoracic surgery(VATS) Xper–CT in combination with real-time fluoroscopy-guided coil in the resection of pulmonary nodules using VATS. Materials and Methods: Precise localization of nodules using Xper-CT in combination with real-time fluoroscopy-guided coil and wedge resection using VATS were conducted on 15 patients with 17 small pulmonary nodules(diameter 0.5–1.5 cm) from April 2015 to January 2016. The value of localization was evaluated in terms of procedure time, type of coils, associated complications of localization, and VATS success rate. Results: The success rate of coil localization was found to be 100% in the primary stage(as shown by the CT scan), and the average procedure time was 30–45 min(35.6 ± 3.05 min). No deaths or major complications occurred. Minor complications included five incidents of pneumothorax(the morbidity was 29.4%, 5/17; no patient required chest tube drainage). The dislocation of coil was found in one patient. The results of pathological examination of 17 small pulmonary nodules revealed 11 primary lung cancers, 1 mesenchymal tumor, 3 nonspecific chronic inflammations, 1 hamartoma, and 1 tuberculosis. Two patients with primary lung cancer underwent lobectomy with mediastinal lymph node dissection. Conclusion: The preoperative precise localization of small pulmonary nodules using Xper-CT-guided coil is an effective and safe technique. It helps in the resection of nodules using VATS. It increases the rate of lung wedge resection with few complications and allows for proper diagnosis with a low thoracotomy conversion rate.

关键词： CT-guided coil localization pulmonary nodule video-assisted thoracic surgery