一种螺旋型Blumlein线的阻抗特性分析

提出了一种结构紧凑的长脉冲发生器,该发生器的螺旋型Blumlein线由内导体（含磁体）、螺旋型中筒和外导体（含磁体）构成,该结构实现了螺旋型Blumlein线和Tesla变压器的一体化。通过对螺旋型Blumlein线的波传输过程分析,给出了慢波系数、开关闭合电流、用于描述形成线闭合开关处界面上波行为的变量因子等参数的计算公式。采用PIC软件对螺旋型Blumlein线的部分波传输过程进行数值模拟,慢波系数等参数的模拟值与计算值基本相符。进行了恒阻抗负载下螺旋型Blumlein线的原理性实验,实验得到的负载波形与编程计算得到的波形基本吻合。     

Efficient pulsed chemical oxygen-iodine laser with instantaneous generation of atomic iodine by volumetric discharge

A pulsed chemical oxygen-iodine laser (COIL) using atomic iodine generated by volumetric discharge of CH 3 I is developed and tested. COIL with a gain length of 60 cm is energized by a square pipe-array jet singlet oxygen generator with basic hydrogen peroxide pumping circulations and operated at subsonic gas flow. Maximum output energy of 4.3 J, pulse duration of 50 μs, specific energy extraction from the active medium of 2.0 J/L, and the maximum chemical efficiency of 12.5% are achieved at a chlorine flow rate of 55 mmole/s.     

主流无载气N_2-氧碘化学激光配气方式的数值优化

针对主流无载气、副流以氮气为载气的氧碘化学激光(COIL),应用求解3维多组分化学反应流方程的数值方法,对流场和物理化学的耦合过程进行细致研究,对副流载气变化带来的问题及性能提升的手段、特别是合理的配气方式进行深入分析。结果表明:传统的在亚声速段进行喷流的配气方式不适用于主流无载气N2-COIL系统,必须采用超声速段射流方式;合理的流量配比条件下,超声速段射流方式COIL光腔位置处增益可达1.5%cm-1;N2-COIL流场边界层厚度明显减小,拓宽了增益的有效分布区域。     

碘气流穿透深度和碘流量对COIL激光输出功率的影响

 通过采用Cl₂流量250mmol/s列管射流式氧发生器的COIL出光实验，得到了激光输出功率随碘副气流相对于氧主气流混合穿透深度的变化规律。实验结果表明，穿透深度对激光功率影响较大，存在最佳穿透深度，约为3.16mm,计算的最佳穿透深度与实验得到的最佳穿透深度基本一致。通过逐步改变供碘系统的碘气流流量，测量激光的输出功率，在实验上证实并找到了COIL的最佳碘流量值，约为4.5mmol/s，这一结果比以往文献所登载的最佳碘流量值要确切。     

氧碘化学激光器输出功率的估算

 建立了激光在工作时的动态模型，即假设在单位时间内，激光介质的粒子数全部被泵浦到上能级。引入激光介质重复泵浦次数的概念，根据能量守恒原理，通过分析氧碘化学激光器(COIL)的传能机理，计算了沿气流方向变化的碘原子上能级的弛豫时间及沿气流方向变化的碰撞传能时间，并且计算了碘原子在出光区内被单重态氧反复泵浦的次数及相应的残余单重态氧数目，从而计算出碘原子在出光区的反复泵浦次数，修正了原计算COIL输出功率的公式。理论计算与实验结果均表明：当碘流量过低时，增益小于损耗，激光器不能起振；当增大碘流量时，激光输出功率也逐步增大，反复泵浦次数逐渐减少；当碘流量继续增大时，激光输出功率达到最大，且在一定碘流量变化范围内基本保持稳定；但随着碘流量的进一步增大，激光输出功率却逐步下降。     

在COIL中碘量变化与激光功率波形的关系

 针对碘量在一定范围内变化对激光功率影响不敏感,采用碘量变化的方法,通过对大量的250mmol/s列管式射流氧发生器的出光实验的分析,得到了激光功率波形随碘量变化的实验规律。这一实验结果可用于根据功率波形变化来调节最佳碘量。并对其机理进行了理论分析。     

氧碘化学激光器增益谱线的精细结构及腔内温度

 采用可调谐二极管激光器做探测光源,测量了超音速氧碘化学激光器增益谱线的精细结构,得到了各谱线相对强度的百分比。同时也推得了增益线宽与腔内温度。     

Semi-gas kinetics model for performance modeling of flowing chemical oxygen-iodine lasers (COIL)

The gas pressure in a laser cavity of flowing chemical oxygen-iodine laser (COIL)is about 133.31333 Pa[1]. In this pressure range, effects of homogeneous and inhomo-geneous broadening competing with each other on the performances of a COIL are no-ticeable. Generally, a rate equation (RE) model is adopted to the performance modeling of a supersonic COIL, such as in refs. [1—4]. This model assumes the spectral line pro-file is homogeneously broadened. Homogeneous broadening assumption sim…     

方列管型射流式O2(1Δ)发生器的COIL出光研究

 方列管型射流式O₂(¹Δ)发生器是一种新型高效的氧碘化学激光器(COIL)化学能源供给装置。描述了采用该发生器在COIL上所做的一系列出光实验,这些实验着重于考察该发生器的性能参数及相应的COIL化学效率。结果在Cl₂流量为0.25mol/s、无冷阱、稳定腔条件下获得化学效率高达26% 。     

COIL基于小信号增益系数的最佳流量配比选择

 氧碘化学激光器(COIL)的混合喷管内发生的是气体动力学、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3维CFD技术,通过求解层流Navier-Stokes方程与组分输运方程,结合10种组分和21个基元反应的化学反应模型,对简化后的化学氧碘激光RADICL模型在亚声速段横向射流情况下,不同的主副流流量配比对小信号增益系数的影响情况进行了比较与分析。结果证明:过高或过低的碘分子浓度均不利于产生合理的小信号增益系数;存在最佳流量配比使小信号增益系数得到显著提高且分布均匀。     

化学氧碘激光器的诊断

 将化学氧碘激光器(COIL)本身的诊断分述为流场特性诊断、气流混合诊断、增益介质诊断和光腔诊断, 系统讨论了各种诊断的要求, 并分别讨论了各种诊断的基本原理及方法。     

氮稀释气体氧碘化学激光3维喷管流动模拟

 应用改进的3维化学反应流程序，对基于RADICL装置、以氮气为稀释气体的化学氧碘激光喷管流动做了数值模拟。给出了达到合适副气流穿深的主副气流匹配条件，考虑了提高水汽流量、改变主副气流总温对增益系数的影响，比较了与以氦气为稀释气体的不同特点。结果发现：氮气作为稀释气体条件下，混合气体的流速低，静压大，在亚声速区驻留时间长，碘分子离解快，使得增益系数峰值增大，且下降快。模拟结果提示：改变喷管结构，将副气流喷孔下移，增益分布得到了改善。     

非均匀增益对激光模式的影响

利用快速傅里叶变换(FFT)法对有正支共焦非稳腔、流动增益介质的化学氧碘激光器(COIL)与二氧化碳激光器的模场进行了数值模拟,在此基础上分析了介质的非均匀增益对激光模式的影响,为新的腔型设计和光束质量的改善提供了依据..     

Novel concept of electric discharge oxygen-iodine laser

A novel concept of discharge oxygen-iodine laser (DOIL) is presented. The supersonic DOIL includes a discharge singlet oxygen generator (DSOG) and discharge atomic iodine generator (DAIG). The operation of DSOG is based on a fast mixing of hybrid argon plasma jet of DC electric arc and RF discharge with a neutral molecular oxygen stream. The goal of our effort is achievement of DOIL oscillations by this new discharge technique, which should provide the singlet oxygen yields exceeding 30% at the total pressures higher than 10 torr. The DAIG operation is based on a cw/pulse RF discharge dissociation of iodine donors directly inside a laser iodine injector. This method substitutes the classic dissociation of molecular iodine by energy of singlet oxygen, which saves its energy for laser generation and so can increase the laser efficiency. The laser power could be thus enhanced by up to 25% if this method is employed in a chemical oxygen-iodine laser (COIL) operation, and even 3 times in DOIL without increase in the iodine laser pumping by singlet oxygen.     

Chemical oxygen-iodine laser with external production of iodine atoms in CH3I/Ar dc glow discharge

A cw chemical oxygen-iodine laser (COIL) operating in a subsonic mode with a high water content of ～15% and external production of iodine atoms in CH₃I/Ar dc glow discharge has been demonstrated. A straightforward comparison of COIL performance for two cases—conventional, when I₂ was injected in the singlet oxygen flow, and when iodine atoms produced externally together with other discharge products were injected—was made. In the latter case nearly four times increase in output power was observed, suggesting that the relaxation of the energy stored in the singlet oxygen slowed down substantially, when the laser operated using CH₃I/Ar discharge products instead of iodine molecules.     

Development of the Chemical Oxygen-Iodine Laser (COIL) with chemical generation of atomic iodine

This article addresses the development of a Chemical Oxygen-Iodine Laser (COIL) with alternative chemical ways of generating atomic iodine. Injection of atomic iodine as opposed to molecular iodine has the potential to improve the COIL efficiency. This paper describes two chemical methods for generating iodine atoms based on the gas phase reactions of hydrogen/deuterium iodide with fluorine or chlorine atoms, which are also produced chemically. Simplified one-dimensional gas dynamic modeling that describes the stream-wise profiles of species concentrations within both reaction systems is used to gain a theoretical understanding of both reaction systems under COIL conditions. The modeling results are used for the design of an experimental device and the interpretation of experimental data. The first experimental investigation studies the production of iodine atoms produced from reactions of Cl with HI. Atomic iodine yields of 70–100% in nitrogen are obtained, and the gain on the I(² P _1/2)–I(² P _3/2) transition in a flow of singlet oxygen is measured. Received: 7 October 2002 / Accepted: 8 February 2003 / Published online: 28 May 2003 RID="*" ID="*"Corresponding author. Fax: +420-2/8689-0527, E-mail: kodym@fzu.cz     

氧碘化学激光器废气排放污染评价北大核心CSCD

氧碘化学激光器运行过程中会将氯气、碘蒸气等有毒有害物质排入大气,对工作场所空气质量和人员健康存在安全隐患。采用点源扩散的高斯模式,建立了小风条件下氧碘化学激光器废气的扩散模型,结合工作场地人员分布情况,计算得到激光器废气排放后15min内,距地面1.5m高度、距排放点500m范围内废气中有毒成分氯气和碘的质量浓度空间分布。根据质量浓度空间分布情况,选取采样点,以Na_2SO_3溶液作为吸收液对氯气和碘进行了同时采样,并采取离子色谱测量了吸收液中氯离子和碘离子的质量浓度。结果表明:氧碘化学激光器废气排入大气后,氯气质量浓度最高为0.200mg/m^3,碘蒸气质量浓度小于检测方法的检出限0.030mg/m^3,低于国家职业卫生标准规定的最高容许质量浓度限值1mg/m^3。     

High throughput jet singlet oxygen generator for multi kilowatt SCOIL

A jet flow singlet oxygen generator (JSOG) capable of handling chlorine flows of nearly 1.5 mol s⁻¹ has been designed, developed, and tested. The generator is designed in a modular configuration taking into consideration the practical aspects of handling high throughput flows without catastrophic BHP carry over. While for such high flow rates a cross-flow configuration has been reported, the generator utilized in the present study is a counter flow configuration. A near vertical extraction of singlet oxygen is effected at the generator exit, followed by a 90° rotation of the flow forming a novel verti-horizontal COIL scheme. This allows the COIL to be operated with a vertical extraction SOG followed by the horizontal arrangement of subsequent COIL systems such as supersonic nozzle, cavity, supersonic diffuser, etc. This enables a more uniform weight distribution from point of view of mobile and other platform mounted systems, which is highly relevant for large scale systems. The present study discusses the design aspects of the jet singlet oxygen generator along with its test results for various operating ranges. Typically, for the intended design flow rates, the chlorine utilization and singlet oxygen yield have been observed to be ∼94% and ∼64%, respectively.     

化学反应与饱和模型对化学氧碘激光性能的影响

 将速率方程（RE）模型与化学动力学模型相结合，讨论了增益饱和模型与化学反应系统对COIL性能的影响。流动为预混的一维模型，考虑了10种成分和21个化学反应，分析计算了未分解碘分子，激发态氧产率，水含量以及温度等因素对COIL性能的影响。计算结果表明，碘流量过多，混合和反应过程中消耗大量能量；碘流量过低，导致粒子数反转和增益过低，对于能量的提取不利。     

连续波氧碘化学激光器小信号增益的测量

描述了利用脉冲光解碘原子激光器作为探测激光器测量连续波氧碘化学激光器小信号增益的方法与装置,给出了增益的测量结果,对实验结果和误差作了简单讨论。