快速富里叶变换算法的计算优化

对快速富里叶变换算法的计算进行了优化,介绍了计算优化的方法和计算效率,在各种计算机上进行计算对比,计算速度平均提高了7到10倍。     

蒙卡中子输运程序JMCT和子通道热工水力程序COBRA-EN耦合计算

介绍了中子输运蒙特卡罗方法与热工水力耦合计算的流程。开发了一套蒙卡中子输运程序JMCT和子通道分析程序COBRA-EN耦合接口。通过33棒束模型的计算展示了考虑耦合计算和不考虑耦合计算的差异,论证了耦合计算在反应堆分析中的重要性。通过对反应堆组件的模拟计算,测试了耦合计算的正确性。最后分析了蒙卡计算的统计涨落和迭代计算过程中收敛标准的关系,讨论了蒙卡中子输运和热工水力耦合过程中收敛标准设置的方案和可行性。     

光学观测中太阳夹角的分析与计算

对影响光学观测效果的太阳夹角计算方法进行了研究。首先给出了太阳夹角的定义及计算公式。然后重点研究了太阳视位置的计算方法,比较了几种赤纬角计算方法,给出了一种改进的时角计算方法,实现了高精度的太阳视位置计算,并对其计算精度进行了分析。最后提出了在实际光学观测应用中的太阳夹角计算算法。实验表明,太阳视位置计算精度比传统数值近似方法高一个数量级,能够满足光学观测中太阳光照分析的需要。     

基于脉管制冷机的二维可压缩流动数值计算程序的开发与应用

本文在SIMPLEC计算程序的基础上,开发了适用于各种流动Mach的计算程序,既能用于计算不可压缩流体,又可以计算可压缩流动。利用此程序计算了一些典型算例,和有关文献结果符合较好。最后利用可压缩程序计算了小孔型脉管制冷机当小孔处于最佳开度时小孔处的气流分布。     

超高速发射实验模型的数值计算

 采用三阶精度PPM（Parabolic Piecewise Method）方法和VOF（Volume of Fluid）相结合,运用Lagrange-Remapping算法,编制了多介质流体高精度欧拉计算程序MFPPM,可以对多介质复杂流场进行数值计算。对程序计算精度进行了测试,并应用于超高速发射实验模型数值计算,对Sandia实验室不带会聚作用的实验模型进行了一维计算以及带会聚作用的实验模型进行二维计算并与其实验结果和CTH计算结果进行对比,其中一维计算最大相对误差1%,二维计算相对误差4.7%,在此基础上对超高速发射设计模型进行了初步计算。     

船用增压锅炉的热平衡计算方法研究

研究了船用增压锅炉的热平衡计算方法。文章简要叙述了增压锅炉烟气侧的工作过程,重点分析了涡轮增压机组在不同锅炉负荷下功率、热力计算及热平衡计算方法。在实例计算部分,验证了增压机组的热损失数学表达式,并分析其计算结果,最终证明计算方法的正确性。     

计算机物理前沿及其与计算机技术的交叉

计算物理学是随着计算技术发展而形成的一门新兴的交叉学科.它是用现代计算技术武装起来的"实验的"理论物理学和"虚拟的"实验物理学.文章回顾了计算物理的发展历史,介绍了计算物理研究状况和前沿问题,并展望了新世纪计算物理面临的挑战.     

涡轮叶栅气热耦合数值模拟

本文建立了透平机械叶栅流场与叶片温度场的气热耦合计算模型,编制了三维非正交曲线坐标系下的温度场求解程序,计算了实心及空心叶片的温度场分布。介绍了区域分解方法在耦合计算及并行计算中的应用,以矩形区域温度场求解程序为例研究了程序的并行化,最后进仃了叶栅流场计算与叶片导热计算程序的分区耦合计算。     

LNG球形贮罐绝热计算

分析了贮罐绝热体的传热规律,并建立了模型。通过近似理论计算得到了通过绝热体的传热量;利用计算软件对绝热体内传热过程进行了有限元计算,获得了通过贮罐绝热体的传热量以及绝热体内温度场的分布。以传热量为基准,将近似理论计算与有限元计算结果进行比较,表明有限元计算结果更为准确。     

加快油藏压力计算收敛速度的数值方法——分区块修正

本文以Watts提出的求解代数方程组的附加修正值法为基础,在油藏压力数值计算中,提出了一种加快油藏压力计算迭代收敛速度的分块修正技术.在计算过程中,将原来的整个计算区块一个修正值,改变成根据边界以及各计算区块孔隙度的不同,对不同的计算区域分块修正.通过计算表明,在同等计算条件下,分块修正技术较之单块修正明显加快了计算迭代收敛速度,最后本文对分块修正加快收敛速度的原因做了分析.     

GJ-341小型遥控光电经纬仪星库星表

本文讨论了星体理论值的计算,并给出了计算程序.     

Resonance studies at STAR

Preliminary results from measurements of resonances (K ^*0(892), $\overline {K*^0 } (892)$ , Φ(1020), and ρ(770)) and weakly decaying particles (Λ(1116), $\bar \Lambda (1116)$ , and K _S ⁰ (498)) are presented. The measurements are performed at mid-rapidity by the STAR detector in $\sqrt {s_{NN} } = 130$ GeV Au?Au collisions at RHIC. The ratios K ^*0/h?, $\overline {K*^0 } /K$ , and $\bar \Lambda /\Lambda $ are compared to measurements at different energies and colliding systems. Estimates of thermal parameters, such as temperature and baryon chemical potential, are also presented.     

B physics at STAR

Results from the search for Γ → e⁺ e^? and $B(\bar B) \to e^ \pm X$ in Au+Au collisions at $\sqrt s = 200$ GeV are presented.     

Proton femtoscopy at STAR

The analysis of two-particle femtoscopy provides a powerful tool to study the properties of matter created in heavy ion collisions. Applied to identical and nonidentical hadron pairs, it makes the study of space-time evolution of the source in femtoscopic scale possible. Baryon femtoscopy allows extraction of the radii of produced sources which can be compared to those deduced from identical pion studies, providing additional information about source characteristics. In this paper we present the correlation functions obtained for protons and antiprotons for Au + Au collisions √s _NN = 62.4 and 200 GeV. On the other hand, as STAR experiment participates in Beam Energy Scan program, we present theoretical predictions of p − p, [`(p)] - [`(p)]\bar p - \bar p and p - [`(p)]p - \bar p femtoscopic measurements, based on UrQMD simulation for √s _NN = 5–39 GeV.     

Resonance production in STAR

The recent results from resonance production in central Au+Au and p+p collisions at $\sqrt {s_{NN} } = 200$ GeV from the STAR experiment at RHIC are presented and discussed.     

Hard physics at STAR

Preliminary results for the production of high transverse momentum hadrons are reported from the STAR detector at the Relativistic Heavy Ion Collider. Negative hadron spectra for 2 < pT < 6 (GeV/c) indicate a suppressed yield compared to expectations from $p\bar p$ collisions at similar energy. The elliptical flow deviates from agreement with predictions based on purely hydrodynamical considerations at pT > 1.5 GeV/c. An initial measurement of the flavor dependence of baryon production at pT ≤ 2.25 GeV/c is also presented and discussed.     

Quarkonia measurements with STAR

We report results on quarkonium production from the STAR experiment at the Relativistic Heavy-Ion Collider (RHIC). J/ψ spectra in p+p and Cu+Cu collisions at  GeV with transverse momenta in the range of 0.5–14 GeV/c and 5–8 GeV/c, respectively, are presented. We find that for p _T >5 GeV/c yields in p+p collisions are consistent with those in minimum-bias Cu+Cu collisions scaled with the respective number of binary nucleon-nucleon collisions. In this range the nuclear modification factor, R _AA , is measured to be 0.9±0.2 (stat). For the first time at RHIC, high-p _T J/ψ-hadron correlations were studied in p+p collisions. Implications from our measurements on J/ψ production mechanisms, constraints on open bottom yields, and J/ψ dissociation mechanisms at high-p _T are discussed. In addition, we give a brief status of measurements of ϒ production in p+p and Au+Au collisions and present projections of future quarkonia measurements based on an upgrades to the STAR detector and increased luminosity achieved through stochastic cooling of RHIC.     

Non-identical particle correlations in STAR

The correlation function of non-identical particles is sensitive to the relative space-time asymmetries in particle emission. Analysing pion-kaon, pion-proton and kaon-proton correlation functions, measured in the Au+Au collisions by the STAR experiment at RHIC, we show that pions, kaons and protons are not emitted at the same average space-time coordinates. The shifts between pion, kaon and proton sources are consistent with the picture of a transverse collective flow. Results of the first measurement of proton-lambda correlations at STAR are in agreement with recent CERN and AGS data.     

Heavy quark results from STAR

I report the most recent measurements on open heavy flavor production at RHIC on behalf of the STAR collaboration. The total charm production cross section in midrapidity at RHIC energy is found to approximately scale by number of binary collisions in d + Au, Cu + Cu and Au + Au collisions. The nuclear modification factor of non-photonic electrons is strongly suppressed in central Au + Au collisions, suggesting substantial heavy quark energy loss at RHIC. The bottom decay contribution to non-photonic electrons was studied via the e–h and e–D ⁰ azimuthal angular correlations. The bottom contribution is found to be important at p _T >5 GeV/c, and is consistent with the FONLL calculation within uncertainties. Charm production through gluon jet splitting was measured by studying the D ^*± contents in the fully reconstructed jets in p+p collisions. This rate is consistent with pQCD evaluation of gluon splitting into a pair of charm quarks and subsequent hadronization.     

Elliptic flow measurements from STAR

In these proceedings some of the highlights of the elliptic flow measurements from STAR at $\sqrt {s_{NN} } = 130$ and 200 GeV for Au + Au collisions are presented.