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非预混条件下的旋转爆轰燃烧室双波头演化过程数值模拟 被引量:4
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作者 孟庆洋 赵宁波 +3 位作者 郑洪涛 刘潇 祁磊 金杉 《航空动力学报》 EI CAS CSCD 北大核心 2019年第1期51-62,共12页
针对旋转爆轰燃烧室双波头演化过程中流场结构变化的问题,对非预混条件下的旋转爆轰燃烧室从起爆到形成稳定的双波头过程进行了数值模拟研究。研究结果表明,从起爆到形成稳定爆轰过程,燃烧室主要经历了起爆、爆轰波对撞和稳定爆轰三个阶... 针对旋转爆轰燃烧室双波头演化过程中流场结构变化的问题,对非预混条件下的旋转爆轰燃烧室从起爆到形成稳定的双波头过程进行了数值模拟研究。研究结果表明,从起爆到形成稳定爆轰过程,燃烧室主要经历了起爆、爆轰波对撞和稳定爆轰三个阶段;在爆轰波对撞阶段,首次对撞是两个爆轰波间的对撞,由于对撞点处缺少新鲜混合气,从而在对撞结束后衰减为两个压力波。第二次对撞是两个压力波间的对撞,因为在第二次对撞点附近存在新鲜混合气来支撑爆轰波的持续传播,故对撞结束后产生了一个爆轰波和一个较弱的压力波;第二次对撞发生后,燃烧室内的压力波反射叠加并形成局部高压区,此高压区压缩气体使气体温度升高,高温气体引燃混合气后,最终发展成为第二个爆轰波;稳定阶段,两个爆轰波均能稳定自持传播,爆轰波峰面压力可达1.45MPa,波后温度为2 500K,爆轰波速度稳定在1 738m/s,产生的推力与比冲分别为79.76N和2312.15s;斜激波的存在使燃烧室出口平面流场产生了较大波动。 展开更多
关键词 旋转爆轰 非预混 双波头 对撞 流场特性
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Two-wave,breather wave solutions and stability analysis to the(2+1)-dimensional Ito equation
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作者 Tukur Abdulkadir Sulaiman Abdullahi Yusuf +2 位作者 Evren Hincal Dumitru Baleanu Mustafa Bayram 《Journal of Ocean Engineering and Science》 SCIE 2022年第5期467-474,共8页
The current study employs the novel Hirota bilinear scheme to investigate the nonlinear model.Thus,we acquire some two-wave and breather wave solutions to the governing equation.Breathers are pulsating localized struc... The current study employs the novel Hirota bilinear scheme to investigate the nonlinear model.Thus,we acquire some two-wave and breather wave solutions to the governing equation.Breathers are pulsating localized structures that have been used to mimic extreme waves in a variety of nonlinear dispersive media with a narrow banded starting process.Several recent investigations,on the other hand,imply that breathers can survive in more complex habitats,such as random seas,despite the attributed physical restrictions.The authenticity and genuineness of all the acquired solutions agreed with the original equation.In order to shed more light on these novel solutions,we plot the 3-dimensional and contour graphs to the reported solutions with some suitable values.The governing model is also stable because of the idea of linear stability.The study’s findings may help explain the physics behind some of the challenges facing ocean engineers. 展开更多
关键词 Governing model Scheme two-waves and breather wave solution Stability analysis Hirota bilinear
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New topological and non-topological unidirectional-wave solutions for the modifie d-mixe d KdV equation and bidirectional-waves solutions for the Benjamin Ono equation using recent techniques
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作者 Marwan Alquran Mohammed Ali Hammad Jadallah 《Journal of Ocean Engineering and Science》 SCIE 2022年第2期163-169,共7页
In this paper,new explicit unidirectional wave solutions for the modified-mixed KdV equation and bidi-rectional waves for the Benjamin Ono equation are studied.New extension of the rational sine-cosine and sinh-cosh m... In this paper,new explicit unidirectional wave solutions for the modified-mixed KdV equation and bidi-rectional waves for the Benjamin Ono equation are studied.New extension of the rational sine-cosine and sinh-cosh methods are used.In addition,an extension of the recent polynomial function method is applied as well.Different types of topological and non-topological soliton solutions are extracted to the proposed models and categorized by providing 2D and 3D graphs.Finally,some physical properties of the new bidirectional waves solutions to the Benjamin Ono model are discussed. 展开更多
关键词 Single-wave solutions two-waves solutions Extended rational sine-cosine method Extended rational sinh-cosh method Polynomial-function method
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利用双平面波干涉面波层析成像方法研究山西断陷盆地及鄂尔多斯地台三维速度结构 被引量:14
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作者 李鹏 周仕勇 +3 位作者 陈永顺 冯永革 姜明明 唐有彩 《CT理论与应用研究(中英文)》 2010年第3期47-60,共14页
本文利用了北京大学在山西地堑的34个台站以及中国地震局台网中心在鄂尔多斯地区46个台站的远震波形数据,运用双平面波干涉的面波层析成像方法,提取瑞利面波相速度频散曲线,开展台阵覆盖区三维速度结构反演,据此分析了研究区地壳和上地... 本文利用了北京大学在山西地堑的34个台站以及中国地震局台网中心在鄂尔多斯地区46个台站的远震波形数据,运用双平面波干涉的面波层析成像方法,提取瑞利面波相速度频散曲线,开展台阵覆盖区三维速度结构反演,据此分析了研究区地壳和上地幔的结构特征。结果表明,瑞利面波相速度分区特征显著,山西断陷盆地和渭河断陷盆地的相速度整体偏低。鄂尔多斯块体在莫霍面以下有明显高速异常,表明该地块为构造稳定的克拉通块体,鄂尔多斯块体的岩石圈下界面在120~140km的深度左右。与此相反,山西断陷盆地和渭河断陷盆地地下70~120km左右均有低速异常,显示这两个地区构造活动活跃,这也与该区域历史上多次发生强震是相符的。 展开更多
关键词 鄂尔多斯 面波层析成像 剪切波速度 双平面波法
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旋转爆轰波中多波流动模式的数值研究 被引量:9
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作者 杨鹏飞 牟乾辉 +2 位作者 滕宏辉 胡宗民 姜宗林 《推进技术》 EI CAS CSCD 北大核心 2019年第2期398-406,共9页
为了研究旋转爆轰燃烧室内复杂的波系结构,特别是爆轰波多波传播模式的影响因素,采用两步诱导-放热总包反应模型,对简化的二维旋转爆轰波进行数值模拟。在不考虑环形爆轰燃烧室曲率的情况下,研究了进口总温和周向尺寸对单波及多波流场... 为了研究旋转爆轰燃烧室内复杂的波系结构,特别是爆轰波多波传播模式的影响因素,采用两步诱导-放热总包反应模型,对简化的二维旋转爆轰波进行数值模拟。在不考虑环形爆轰燃烧室曲率的情况下,研究了进口总温和周向尺寸对单波及多波流场结构的影响。结果表明,一定范围内进口总温的增加会使得爆轰波的波头数目增加,且双波流场结构中存在双波对撞和双波同向两种传播形式,双波同向传播和三波同向传播之间则稳定存在着两组双波对撞流场,且有对应的温度范围;对于双波对撞模式,持续减小周向尺寸能够使得流场结构转变成单波模式;周向尺寸的增加则会使得双波对撞向双波同向传播模式转变。 展开更多
关键词 旋转爆轰波 总温 双波对撞 双波同向
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柱面内爆驱动下铅飞层对碰区动载行为的实验研究 被引量:5
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作者 张崇玉 胡海波 李庆忠 《高压物理学报》 CAS CSCD 北大核心 2013年第6期884-888,共5页
采用光学阴影照相和脉冲X光照相,对柱面内爆对碰驱动下铅飞层对碰区凸起行为进行了实验研究。实验结果显示,铅飞层对碰区出现严重的射流状超前凸起,凸起行为表现出明显的失稳发展倾向。由于对碰产生高压,因此铅飞层对碰区可能完全熔化,... 采用光学阴影照相和脉冲X光照相,对柱面内爆对碰驱动下铅飞层对碰区凸起行为进行了实验研究。实验结果显示,铅飞层对碰区出现严重的射流状超前凸起,凸起行为表现出明显的失稳发展倾向。由于对碰产生高压,因此铅飞层对碰区可能完全熔化,变成名义上无剪切强度的流体。材料的低强度、低熔点(冲击熔化压力)性能是造成铅飞层对碰区出现射流状超前凸起现象的主要因素。还观察到对碰区出现3个超前凸起现象,初步分析可能是由于柱面滑移爆轰波对碰导致的波系反射、叠加造成的,具体原因还有待于进一步分析研究。 展开更多
关键词 柱面内爆 爆轰波对碰 铅飞层 对碰区凸起 冲击熔化
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New exact solutions of a (3+1)-dimensional Jimbo-Miwa system 被引量:1
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作者 陈元明 马松华 马正义 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第5期247-251,共5页
By using the (G'/G)-expansion method and the variable separation method, a new family of exact solutions of the (3+1)-dimensional Jimbo-Miwa system is obtained. Based on the derived solitary wave solutions, we o... By using the (G'/G)-expansion method and the variable separation method, a new family of exact solutions of the (3+1)-dimensional Jimbo-Miwa system is obtained. Based on the derived solitary wave solutions, we obtain some special localized excitations and study the interactions between two solitary waves of the system. 展开更多
关键词 (3+1)-dimensional Jimbo-Miwa system (G'/G)-expansion method exact solutions interactionsbetween two solitary waves
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Interaction of Two Pulsatory Waves of the Korteweg-de Vries Equation in a Zigzag Hyperbolic Structure
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作者 Victor A. Miroshnikov 《American Journal of Computational Mathematics》 2014年第3期254-270,共17页
A new exact solution for nonlinear interaction of two pulsatory waves of the Korteweg-de Vries (KdV) equation is computed by decomposition in an invariant zigzag hyperbolic tangent (ZHT) structure. A computational alg... A new exact solution for nonlinear interaction of two pulsatory waves of the Korteweg-de Vries (KdV) equation is computed by decomposition in an invariant zigzag hyperbolic tangent (ZHT) structure. A computational algorithm is developed by experimental programming with lists of equations and expressions. The structural solution is proved by theoretical programming with symbolic general terms. Convergence, tolerance, and summation of the ZHT structural approximation are discussed. When a reference level vanishes, the two-wave solution is reduced to the two-soliton solution of the KdV equation. 展开更多
关键词 KDV Equation two Pulsatory waves ZHT Structure Experimental THEORETICAL Computation
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双源连续波对引信的辐照效应研究 被引量:1
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作者 赵国梁 魏光辉 +2 位作者 卢新福 潘晓东 刘东平 《军械工程学院学报》 2014年第4期34-37,共4页
为研究复杂电磁环境对某引信的影响,从双源连续波入手,运用双源连续波对工作状态某引信辐照的实验方法进行实验.实验结果表明,在以引信工作频率为中心的150MHz频率范围内对加电引信进行双源连续波辐照实验可使引信发火,辐照结束后引信... 为研究复杂电磁环境对某引信的影响,从双源连续波入手,运用双源连续波对工作状态某引信辐照的实验方法进行实验.实验结果表明,在以引信工作频率为中心的150MHz频率范围内对加电引信进行双源连续波辐照实验可使引信发火,辐照结束后引信工作正常,实验的重复性较好.两连续波频率间隔不同,可使引信发火的场强组合数值大小不相同,实验中当两连续波远离引信工作频率且频差10MHz以上时,发火场强组合近似呈线性.最后对双源连续波对引信的辐照效应机理作了分析,两连续波频率间隔不同,引信发火机理不同. 展开更多
关键词 无线电引信 双源连续波 实验方法 辐照效应 效应机理
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基于数码相机的双棱镜实验 被引量:1
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作者 王凤鹏 阙斌 +3 位作者 陈艳 陈莹 侯淼春 胡肇高 《赣南师范大学学报》 2020年第6期39-42,共4页
提出了一种利用数码相机实现双棱镜干涉实验的方案.利用数码相机替代传统实验中的测微目镜观察并记录干涉条纹和双缝像,再利用Matlab等软件测出干涉条纹间隔及双缝距离.该方案不仅可验证双缝干涉原理,还可以验证平行光干涉原理.通过实... 提出了一种利用数码相机实现双棱镜干涉实验的方案.利用数码相机替代传统实验中的测微目镜观察并记录干涉条纹和双缝像,再利用Matlab等软件测出干涉条纹间隔及双缝距离.该方案不仅可验证双缝干涉原理,还可以验证平行光干涉原理.通过实验验证了实验方案的可行性,并讨论了利用数码相机进行双棱镜实验的特点和优势. 展开更多
关键词 菲涅耳双棱镜 数码相机 双缝干涉 平行光干涉
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饱和土一维简谐响应解析解的求解和应用:II应用 被引量:1
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作者 杨军 宋二祥 陈肇元 《岩土力学》 EI CAS CSCD 北大核心 2003年第5期710-714,共5页
将相关论文[1]中得到的饱和土一维简谐响应解析解,应用到饱和土中两类压缩波的独立作用、饱和土中波的传播速度、u-p方程的适用范围等研究中。在两类压缩波的独立作用研究中,克服了以前文献中的数学不严密性。研究了饱和土各参数对三种... 将相关论文[1]中得到的饱和土一维简谐响应解析解,应用到饱和土中两类压缩波的独立作用、饱和土中波的传播速度、u-p方程的适用范围等研究中。在两类压缩波的独立作用研究中,克服了以前文献中的数学不严密性。研究了饱和土各参数对三种体波波速的影响。通过比较u-w和u-p方程的解答,定量地说明了u-p方程的适用范围。 展开更多
关键词 饱和土 两个压缩波的独立作用 波速 u-p方程
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用频装备的双源连续波辐照干扰预测研究
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作者 郭玉冰 魏光辉 +2 位作者 赵国梁 潘晓东 卢新福 《弹箭与制导学报》 CSCD 北大核心 2016年第5期119-122,共4页
为研究复杂电磁环境下用频装备的电磁辐射效应预测方法,设计了某无线电引信多源电磁辐照干扰试验方法。试验研究了某无线电引信双源连续波辐照干扰效应,得到了引信在不同频率连续波组合下发火的临界干扰场强组合。分别以数值分析方法和... 为研究复杂电磁环境下用频装备的电磁辐射效应预测方法,设计了某无线电引信多源电磁辐照干扰试验方法。试验研究了某无线电引信双源连续波辐照干扰效应,得到了引信在不同频率连续波组合下发火的临界干扰场强组合。分别以数值分析方法和能量型干扰机理为理论依据,提出了两种双源连续波辐照下引信电磁干扰的预测模型。通过两种预测模型得到的相同频率下临界干扰场强组合与试验数据基本一致,证明了两种双源连续波辐照干扰预测方法的有效性。 展开更多
关键词 双源连续波 电磁干扰 辐照效应 预测 插值法 能量型干扰
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缺失数据下的两步抽样法估计
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作者 陆福忠 《高校应用数学学报(A辑)》 CSCD 北大核心 2009年第1期39-46,共8页
在数据缺失机制形式未知时,通过两步抽样得到了分布函数的相合估计量,证明了该估计量的渐近正态性.文中假设第二次抽样时的数据缺失机制与第一次抽样时的数据缺失机制函数形式类似,允许两者有一个一维未知参数的差别.
关键词 数据缺失机制 两步抽样 分布函数
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双光束干涉中的近轴条件
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作者 杨艳芳 齐美彬 《安徽工学院学报》 1997年第3期27-32,共6页
在分析双光束干涉时,近轴条件是一个很重要的前提条件。同时,它也具有较强的实用意义。
关键词 双光束干涉 近轴条件 干涉
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Diffusion-induced deflection and the effect of two-wave mixing gain on dissipative photovoltaic solitons 被引量:2
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作者 刘时雄 刘劲松 +2 位作者 张绘蓝 张光勇 王程 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第5期1391-1398,共8页
In an open-circuit dissipative photovoltaic (PV) crystal, by considering the diffusion effect, the deflection of bright dissipative photovoltaic (DPV) solitons has been investigated by employing numerical techniqu... In an open-circuit dissipative photovoltaic (PV) crystal, by considering the diffusion effect, the deflection of bright dissipative photovoltaic (DPV) solitons has been investigated by employing numerical technique and perturbational procedure. The relevant results show that the centre of the optical beam moves along a parabolic trajectory, while the central spatial-frequency component shifts linearly with the propagation distance; furthermore, both the spatial deflection and the angular derivation are associated with the photovoltaic field. Such DPV solitons have a fixed deflection degree completely determined by the parameters of the dissipative system. The small bending cannot affect the formation of the DPV soliton via two-wave mixing. 展开更多
关键词 DEFLECTION dissipative photovoltaic soliton two-wave mixing
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Quasistable bright dissipative holographic solitons in photorefractive two-wave mixing system 被引量:1
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作者 刘劲松 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第1期165-172,共8页
The dynamical evolution of both signal and pump beams are traced by numerically solving the coupled-wave equation for a photorefractive two-wave mixing system. The direct simulations show that, when the intensity rati... The dynamical evolution of both signal and pump beams are traced by numerically solving the coupled-wave equation for a photorefractive two-wave mixing system. The direct simulations show that, when the intensity ratio of the pump beam to the signal beam is large enough, the pump beam presents a common decaying behaviour without modulational instability (MI), while the signal beam can evolve into a quasistable spatial soliton within a regime in which the pump beam is depleted slightly. The larger the ratio is, the longer the regime is. Such quasistable solitons can overcome the initial perturbations and numerical noises in the course of propagation, perform several cycles of slow oscillation in intensity and width, and persist over tens of diffraction lengths. From physical viewpoints, these solitons actually exist as completely rigorous physical objects. If the ratio is quite small, the pump beam is apt to show MI, during which the signal beam experiences strong expansion and shrinking in width and a drastic oscillation in intensity, or completely breaks up. The simulations using actual experimental parameters demonstrate that the observation of an effectively stable soliton is quite possible in the proposed system. 展开更多
关键词 spatial optical solitons photorefractive nonlinear optics two-wave mixing
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Evolution and stability of spatial solitons in a photorefractive two-wave mixing system
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作者 刘劲松 张慧蓝 +1 位作者 张光勇 王程 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第2期394-402,共9页
The dynamical evolution and stability of bright dissipative holographic solitons in biased photorefractive materials in which the self-trapping beam obtains a gain from the pump beam via two-wave mixing has been inves... The dynamical evolution and stability of bright dissipative holographic solitons in biased photorefractive materials in which the self-trapping beam obtains a gain from the pump beam via two-wave mixing has been investigated numerically. Results show that these solitons are stable relative to small perturbations. Adjusting some system parameters, such as the bias field and the angle between beams, can easily control the generation of such solitons. Potential applications in optical switches or repeaters are discussed. 展开更多
关键词 spatial optical solitons photorefractive nonlinear optics two-wave mixing
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High Efficiency Photorefractive BaTiO_3 Plate for Optical Image Processing
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作者 顾向光 朱镛 +1 位作者 张大鹏 叶伯琦 《Chinese Science Bulletin》 SCIE EI CAS 1993年第17期1424-1427,共4页
45°-cut BaTiO<sub>3</sub> crystals have been studied and used for their enhanced photorefractive performance. Theoretically, BaTiO<sub>3</sub> crystal has its maximum two-wave mixing (TWM... 45°-cut BaTiO<sub>3</sub> crystals have been studied and used for their enhanced photorefractive performance. Theoretically, BaTiO<sub>3</sub> crystal has its maximum two-wave mixing (TWM) gain when the grating wave vector K<sub>g</sub> is about 45° tilted with respect to its C-axis. However, for thick samples, the effective gain is usually reduced because of the fanning problem. At steady states, the effective TWM gain of a 45°-cut BaTiO<sub>3</sub> is normally 展开更多
关键词 two-wave MIXING optical image processing 45°-cut BaTiO3 crystals.
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N-soliton solutions for the nonlocal two-wave interaction system via the Riemann–Hilbert method
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作者 Si-Qi Xu Xian-Guo Geng 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第12期157-163,共7页
In this paper, a nonlocal two-wave interaction system from the Manakov hierarchy is investigated via the Riemann–Hilbert approach. Based on the spectral analysis of the Lax pair, a Riemann–Hilbert problem for the no... In this paper, a nonlocal two-wave interaction system from the Manakov hierarchy is investigated via the Riemann–Hilbert approach. Based on the spectral analysis of the Lax pair, a Riemann–Hilbert problem for the nonlocal two-wave interaction system is constructed. By discussing the solutions of this Riemann–Hilbert problem in both the regular and nonregular cases, we explicitly present the N-soliton solution formula of the nonlocal two-wave interaction system. Moreover,the dynamical behaviour of the single-soliton solution is shown graphically. 展开更多
关键词 nonlocal two-wave interaction system Riemann–Hilbert problem N-soliton solutions
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The influence of stimulated temperature-dependent emission cross section on intracavity optical parametric oscillator
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作者 S Samimi A Keshavarz 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第2期238-241,共4页
In this paper, the influence of temperature on the intracavity optical parametric oscillator(IOPO) is investigated by using the stimulated temperature-dependent emission cross section of laser crystal. The rate equa... In this paper, the influence of temperature on the intracavity optical parametric oscillator(IOPO) is investigated by using the stimulated temperature-dependent emission cross section of laser crystal. The rate equations under plane wave approximation have been used for simulation of signal output pulse. Results show that the signal output pulse width is decreased by increasing the laser crystal temperature. Also, the signal output energy is increased by the increasing of the laser crystal temperature. The simulation results for IOPO based on Nd:YAG and Nd:YVO_4, show that the signal pulse energies are increased by 3.2 and 5.6 times respectively when the laser crystal temperature increased from 15℃ to 300℃. The presented model indicates that the temperature sensitivity of Nd:YVO_4-based IOPOs is more than that of Nd:YAG-based IOPOs which is expected from a physical point of view. 展开更多
关键词 nonlinear optic two-wave mixing parametric oscillators and amplifiers
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