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1.
根据HCSB-DEMO堆的设计要求,对不同尺寸的聚变堆能产生的聚变功率、中子壁负载和等离子体燃烧时间等进行计算与分析,给出了符合设计要求的堆芯参数。在所选定的堆芯参数条件下进行了零维功率平衡计算分析,给出了3组HCSB-DEMO堆的等离子体初步设计参数。  相似文献   

2.
运用零维模型分析了液态锂作为包层流动液帘与堆芯等离子体的兼容性,得到了液态锂工作温度对堆芯有效平均等离子体电荷Zeff、燃料稀释以及聚变功率之间的关系。结果表明在正常工作情况下,液态锂的蒸发对Zeff的影响不是很严重,但对燃料稀释和聚变功率的影响却较为敏感。在具有较高功率密度的反剪切位形聚变实验增殖堆FEB E设计方案Ⅱ的条件下,计算了液态锂的流速与它表面最大温升的关系,结果表明,即便对0.5m·s-1的低速流动液态锂,其蒸发对聚变等离子体的影响甚微。最后对氢同位素饱和状态下液态锂包层表面的溅射作了初步的讨论。  相似文献   

3.
同轴磁场对非平衡磁控溅射系统放电特性的影响   总被引:1,自引:1,他引:0  
采用激励电流可以调整的电磁线圈来激发非平衡磁场,调整约束磁场和放电空间等离子体状态。实验结果表明调整非平衡磁场显著影响系统的放电特性,使放电特性偏离常规的磁控溅射系统放电特性,增强了等离子体的引出效果。在Ar放电的条件下,详细研究了溅射系统的工作伏安特性随不同的工作气体、气压和溅射功率的变化规律。根据蔡尔得公式,讨论了非平衡磁场对于磁控溅射系统中放电特性的影响规律。  相似文献   

4.
大气压非平衡等离子体中非平衡度的探讨   总被引:9,自引:2,他引:7  
讨论了大气压非平衡等离子体中的非平衡度及它和各种参数的关系,并针对几类重要的大气压非平衡等离子体的产生技术,分析了每种产生技术的特点及和非平衡度的要求  相似文献   

5.
本工作描述我们编制的零维三流体粒子和功率平衡的等离子体动力学时关模拟程序。在物理上我们把等离子体动力学与新经典轮运理论结果结合起来,通过辅助加热、燃料粒子注入速率和纵场纹波控制堆芯等离子体燃烧。数值结果表明,通过控制完全可以实现堆芯等离子体的稳定燃烧和排灰要求。  相似文献   

6.
提出通过离子-电子非平衡物理模型来降低惯性约束聚变中心热斑点火的聚变点火条件。在该物理模型中,强调离子比电子具备更高的温度,从而使得热斑的热核聚变反应增强,轫致辐射和电子热传导造成的能量漏失相对降低。通过对中心热斑的自加热分析和热斑燃烧动力学分析,发现相对于平衡聚变点火模型,非平衡模型可以显著扩大聚变点火区在热斑面密度和热斑温度空间的范围。同时采用LARED-S程序的数值模拟,研究了通过尖峰脉冲波形、二次冲击物理机制强化中心热斑聚变点火的非平衡性。  相似文献   

7.
陈一平  徐强 《计算物理》1994,11(3):346-352
用四阶龙格-库塔方法求解聚变-裂变混合反应堆堆芯等离子体动力学方程组,求解过程采用分段步长法,既可保证求解精度又可节省机时,所得出的解的曲线能充分反映堆芯等离子体的燃烧过程。求解过程还引用数值反馈控制方法用以对解曲线的优化和控制。这种数值反馈控制方法可以在工程技术上用来探索堆芯等离子体燃烧过程的控制。  相似文献   

8.
薄勇  赵青  罗先刚  刘颖  陈禹旭  刘建卫 《物理学报》2016,65(3):35201-035201
采用流场模拟软件模拟了十一组分RAM-II飞行器表面等离子体鞘套的分布,提取了四个典型飞行高度、飞行状态下的等离子体鞘套的分布信息.然后根据RAM-II飞行器等离子体鞘套数据,利用计算色散介质的Z变换FDTD方法主要计算了电磁波在四个不同高度处等离子体鞘套中的功率反射系数和功率透射系数.此外,根据目前可以做出的磁场强度的大小,对四个不同高度下的非均匀等离子体鞘套层按距飞行器表面的距离进行相应的非均匀磁化.由于左旋极化波和右旋极化波在磁化等离子体中的传输特性不同,最后对比了左旋极化波、右旋极化波在非磁化和磁化情况下的传输特性,对飞行器导航通信磁窗天线的设计给出建议.  相似文献   

9.
根据中国聚变工程实验堆(CFETR)堆芯设计参数及燃料系统流程模型,采用平均停留时间方法,建立燃料循环子系统的氚转移模型用来描述氚在各子系统之间的输运、滞留等过程。采用该模型,分析了不同聚变功率水平、运行因子以及燃烧率对中国聚变工程实验堆的氚平衡以及启动氚投料量的影响。  相似文献   

10.
在张海峰等的评文 (以下简称评文 )中提到 ,总出射波振幅应等于每层等离子体反射与透射振幅的矢量和 ,而在我们文章中认为总出射功率等于每层等离子体反射与透射功率之和。我们认为在对空间取平均后 ,这两种观点是一致的。与我们原来文章的假定一样 ,我们设非均匀等离子体层的厚度为d。电磁波由等离子体的一侧入射 ,另一面为金属反射面。电磁波电场的极化方向如图 1所示。取z轴垂直于等离子体层 ,平衡等离子体密度在z方向具有非均匀性。E′i 为电磁波在第i层与第i + 1层界面反射后 ,最后射出等离子体层的出射电场矢量为 :E′i =-E…  相似文献   

11.
吴雪科  李会东  王占辉  冯灏  周雨林 《中国物理 B》2017,26(6):65201-065201
Using the trans-neut module of the BOUT++ code, we study how the fueling penetration depth of supersonic molecular beam injection(SMBI) is affected by plasma density and temperature profiles. The plasma densities and temperatures in L-mode are initialized to be a set of linear profiles with different core plasma densities and temperatures. The plasma profiles are relaxed to a set of steady states with different core plasma densities or temperatures. For a fixed gradient, the steady profiles are characterized by the core plasma density and temperature. The SMBI is investigated based on the final steady profiles with different core plasma densities or temperatures. The simulated results suggest that the SMB injection will be blocked by dense core plasma and high-temperature plasma. Once the core plasma density is set to be N_(i0)= 1.4N_0(N_0= 1 × 10~(19)m~(-3)) it produces a deeper penetration depth. When N_(i0) is increased from 1.4N_0 to 3.9N_0 at intervals of 0.8N_0, keeping a constant core temperature of T_(e0)= 725 eV at the radial position of ψ = 0.65, the penetration depth gradually decreases. Meanwhile, when the density is fixed at N_(i0)= 1.4N_0 and the core plasma temperature T_(e0) is set to 365 eV,the penetration depth increases. The penetration depth decreases as T_(e0) is increased from 365 eV to 2759 eV. Sufficiently large N_(i0) or T_(e0) causes most of the injected molecules to stay in the scrape-off-layer(SOL) region, lowering the fueling efficiency.  相似文献   

12.
For application to floating nanodots gate memory, ferritin core, ferrihydrite nanodot, array was made and reduced to be conductive. Ammonia plasma treatment was employed to reduce the ferrihydrite cores. X-ray photoelectron spectroscopy analysis confirmed that the plasma treated cores embedded in a SiN film are successfully reduced from ferrihydrite to metal iron. It was elucidated that hydrogen radicals or ions in the plasma combine with oxygen atoms in the core and, consequently, the core is reduced to a conductive state. Transmission electron microscope analysis before and after the treatment showed that the reduced core size was smaller than ferrihydrite core by approximately 2 nm, which is consistent with theoretical calculation of the shrink size accompanying core reduction to α-Fe. The plasma treated cores embedded in SiO2 film are found to be iron oxides, which indicates that the metal iron nanodots are vulnerable to oxygen and easy to be reoxidized.  相似文献   

13.
边界杂质注入是未来聚变装置ITER用于增强边界辐射,减少第一壁热负荷的一种重要方法。但部分注入的杂质会被输运到芯部,造成主等离子体辐射损失以及约束下降。光谱观测可以获取杂质种类、含量和分布等信息,在理解等离子体中杂质输运方面起着重要作用。在EAST(experimental advanced superconducting tokamak)偏滤器氩气(Ar)注入实验中,利用偏滤器可见光谱和芯部极紫外光谱监测边界的Ar1+离子谱线Ar Ⅱ(401.36 nm)和芯部的Ar15+离子谱线Ar ⅩⅥ(35.39 nm),并获得两者强度随时间的变化。其中,Ar Ⅱ和Ar ⅩⅥ的电离能分别为27和918 eV,因此,Ar Ⅱ和Ar ⅩⅥ分别对应分布于等离子体边界和芯部Ar离子。为了分析二者谱线强度随时间变化的特征,发展了一种基于正则Pearson积矩相关系数的相关分析方法,计算得到两者谱线强度变化的相对延迟时间,以此表征杂质从边界向芯部输运的时间。结果显示,偏滤器注入Ar杂质后,芯部Ar ⅩⅥ辐射增长滞后于边界Ar Ⅱ辐射的增长,并且在具有较高的低杂波加热功率的放电中,两者的延迟时间较长,表明较高的低杂波加热功率可以延长杂质从边界向芯部输运的时间。  相似文献   

14.
杨涓  苏纬仪  毛根旺  夏广庆 《物理学报》2006,55(12):6494-6499
为了提高微波等离子推力器性能,改善等离子体对电磁波能量的吸收状况,提高核心区温度,提出外加磁场的方案,并对热等离子体进行了数值模拟.假设局域热平衡条件,采用Navier-Stokes,Maxwell和Saha方程,利用压力修正的半隐格式和时域有限差分求解方法,建立了径向磁镜场下推力器内等离子体流场的数值计算模型.数值模拟结果表明:外加磁场后的磁感应强度小于0.5 T时,推力器内热等离子体核心区最高温度随磁感应强度的增加而迅速提高.外加磁场后的磁感应强度大于0.5 T时,核心区最高温度随磁感应强度的增加而缓慢提高.磁感应强度为0.5 T时,热等离子体核心区最高温度与不加磁场相比提高了24%.外加磁场对等离子体流场速度分布影响不大. 关键词: 等离子体模拟 等离子体相互作用 等离子体流动  相似文献   

15.
Several attempts to model the entire plasma cross section have been reported in the last few years. Two possibilities are to either couple a core code to a scrape-off layer (SOL) code at a specified interface or to extend the computational region of an SOL-code all the way to the plasma centre. The most advanced global code is the code COCONUT which is based on the former principle and comprises the Monte-Carlo code NIMBUS, the 2D scrape-off layer code EDGE2D, the core transport code JETTO and the core impurity transport code SANCO. A main feature of COCONUT is its modular structure which ensures a high degree of flexibility and the capability to cover a large range of time-scales. The influence of the SOL on the core is lllustrated with a range of global simulations carried out with COCONUT. The simulations show that the primary effect of the SOL is the control of the particle sources and sinks with a secondary effect on plasma dilution, radiation and perhaps pedestal temperatures.  相似文献   

16.
Results are presented from the measurements of the radial coherence between the plasma density fluctuations in the core and at the edge of the plasma column in the L-2M stellarator. It is found that the radial coherence between these fluctuations is fairly high: the coherence coefficient attains a value of higher than 0.5 for the spectral wavelet components with frequencies lying in the range from several kilohertz to 30 kHz. The statistical characteristics of density fluctuations are also studied. It is shown that the power distribution function of the plasma density fluctuations in the plasma core differs from Gaussian.  相似文献   

17.
刘才根  钱尚介  万华明 《物理学报》1998,47(9):1515-1519
提出了一个驱动托卡马克芯部等离子体极向旋转的新途径:用电子回旋波产生芯部等离子体极向旋转.物理机制如下:在高功率的电子回旋波加热的托卡马克等离子体中,共振局域化现象将产生极向电场从而形成极向外高内低的离子密度分布;这个极向离子的积累可以克服来自磁泵的阻尼而使等离子体极向旋转退稳定.从流体力学方程和漂移动力学方程中,得到了等离子体旋转退稳的判别式.结果表明现有的电子回旋波加热功率水平可以驱动芯部等离子体的极向旋转. 关键词:  相似文献   

18.
R. Janma  S.P. Singh  V. Dwivedi 《Optik》2011,122(2):173-176
The modal dispersion characteristics of EM waves in a new unconventional plasma loaded doubly clad waveguide having a shape of the lemniscates of Bernoulli-type core cross-section have been studied analytically. The proposed waveguide has three parts namely the core with slighter high index, the inner cladding with plasma and the outer cladding with air. Now using the necessary orthogonal coordinates for the proposed structure and imposing the boundary conditions under the weak guidance condition, the modal characteristics equation has been obtained considering variations in plasma width and plasma frequency, the dispersion curves and cutoff frequencies have been obtained and presented in this paper. It is noted that as the width of plasma layer increases, the cutoff frequency also increases considerably in all considered cases. This shows that using plasma width as a new parameter we can control any particular mode on our wish.  相似文献   

19.
在EAST装置上安装了X模极化W波段多道相关反射仪,用于测量等离子体芯部密度涨落。该诊断利用低损耗(<3dB)多工器将4个不同频率(79.2GHz,85.2GHz,91.8GHz和96GHz)的微波耦合在一起,通过同一个天线发射。反射波由两个极向分离(~5cm)的天线接收,通过下变频技术实现外差测量。通过对两个极向天线接收的信号进行相关分析,获得芯部湍流垂直速度。对2018年低约束模式(L模)放电进行分析发现,在电子回旋共振加热(ECRH)等离子体中,芯部湍流垂直速度在电子逆磁漂移方向。而在注入同向中性束(co-NBI)后,芯部湍流垂直速度变为离子逆磁漂移方向。  相似文献   

20.
It is shown that the efflux of impurities injected into the core plasma can be detected by collector probes in the scrape-off plasma. The time evolution, orientation and radial dependences of these effluxes allow to conclude on the impurity confinement in the core plasma and the scrape-off plasma. Moreover, recycling effects can also be measured.  相似文献   

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