气液双热源耦合热泵空调性能模拟研究

建立了气液双热源耦合换热器的耦合换热模型,并对其在耦合热源热泵空调中应用时的制热工况进行了性能模拟研究。模拟结果显示,使用该气液双热源耦合式换热器的耦合热源热泵空调系统,气液双热源模式与单空气热源模式相比,制热量和COP均有明显提高,低温时性能提高更为显著。当室外温度为-15℃时,双热源热泵的制热量较单一空气源热泵提高比例进一步增大,制热量提高近40%,COP提高近30%。     

Radon Emanation in Partially Saturated Porous Media

Radon emanation which is the fraction of radon-222 atoms released in the connected pore space of a porous material, increases when the water content increases because of the low recoil range of this atom in water compared with air. This complex phenomenon is studied using reconstructed porous media and random packings where the phase distribution is obtained by a lattice Boltzmann technique incorporating interfacial tension and wetting. The influence of the pore structure, of the recoil range and of saturation, is systematically studied. The numerical results are in good agreement with data from uranium mine tailings.     

Investigating the diameter of solid particles effects on a laminar nanofluid flow in a curved tube using a two phase approach

In this paper, we report the results of our numerical studies on laminar mixed convection heat transfer in a circular Curved tube with a nanofluid consisting of water and 1 vol.% Al₂O₃. Three dimensional elliptic governing equations have been used. Two phase mixture model and control volume technique have been implemented to study flow field. Effects of the diameter of particles on the hydrodynamic and thermal parameters are investigated and discussed. Increasing the solid particles diameter decreases the Nusselt number and secondary flow, while the axial velocity augments. When the particles are in order of nano meter, increasing the diameter of particles, do not change the flow behaviors. The distribution of solid nanoparticles is uniform and constant in curved tube.     

Simulation of particle/fluid flows in vertical circular pipes

A two fluid continuum model is applied to the simulation of steady fully developed particle/fluid flow in a vertical circular pipe. Both closed form and numerical solutions are obtained to the associated governing equations. These solutions are compared to the predictions of another two fluid continuum model. These comparisons are used to illustrate the differences in the predictions of two widely used models, even in the fundamental problem of steady flow in a circular pipe.     

用直接方法和希耳伯变换计算二维瞬态势及其梯度

本文用直接方法和希耳伯变换给出了计算二维瞬态势及其梯度的新方法.这种方法可以计算复杂度从传统的O(N_t²)降低到O(N_t).在计算势及其梯度时,该方法的直接计算中所用的权重因子不随时间变化,因此它们只需在第一个时间步长时计算一次.所以,当用于二维瞬态散射的时间推进算法中时,该方法可节省大量的CPU时间.数值结果表明该方法的精度非常高.     

生物样品的散射和吸收特性对双光子激发和共焦成象深度的影响

本文研究了生物样品的散射和吸收特性对双光子激发和共焦成象深度的影响.生物组织内30μm的成象结果表明,双光子激发具有比共焦成象更深的成象深度.来自生物组织的模型实验和蒙特卡罗模拟均表明,散射和吸收的影响是导致这一特点的重要原因.     

Numerical Simulation of Mixing in a Micro-well Scale Bioreactor by Computational Fluid Dynamics

ＩｎｔｒｏｄｕｃｔｉｏｎＳｈａｋｅｆｌａｓｋｓａｒｅｕｓｅｄｒｏｕｔｉｎｅｌｙｉｎｔｈｅｐｈａｒｍａｃｅｕ ｔｉｃａｌ,ｂｉｏｃｈｅｍｉｃａｌａｎｄｍｅｄｉｃａｌｆｉｅｌｄｓｆｏｒｃｅｌｌｇｒｏｗｔｈｃｕｌｔｕｒｅ ,ｍｅｄｉａｓｃｒｅｅｎｉｎｇａｎｄｆｏｒｃｅｌｌｅｘｐａｎｓｉｏｎ .Ｓｈａｋｅｆｌａｓｋｆｅｒｍｅｎｔａｔｉｏｎｒｅｑｕｉｒｅｓｒｅｌａｔｉｖｅｌｙｓｍａｌｌａｍｏｕｎｔｓｏｆｍａｔｅｒｉａｌ,ｔｙｐｉｃａｌｌｙｂｅｔｗｅｅｎ 5 0ａｎｄ 5 0 0ｍＬ ,ａｎｄｒｅｌｉｅｓｏｎａｈｏｒｉｚｏｎ…     

过硫代碳酸配体［CS4］2-生成的新方法［Me4N］n［Cu(CS4)］n(I)和［Me4N］4［Cu4(CS4)4］(Ⅱ)的合成与晶体结构

用硒酚铜簇合物和硫酚铜簇合物[Me4N]2[Cu4(EPh)6](E=Se和S）与CS2及少量S反应,分别获得了以过硫代碳酸根[CS4]^2-为配体的[Me4N]n[Cu(CS4)]n(I)和[Me4N]4[Cu4(CS4)4](Ⅱ）。并用X射线单晶衍射法测定了它们的晶体结构。I为二维层状聚合物,Ⅱ为四核铜簇阴离子化合物。并对[CS4]^2-形成的机理作了讨论。     

二维泡沫稳定性与拓扑学性质的关系研究

研究了二维泡沫形成、进化及其拓扑学性质随时间的变化关系以及影响其稳定性的因素.探索了二维泡沫初始有序化的气泡进化和完全无序化的气泡进化的两种过程,并分析在无序化气泡的进化过程中,平均气泡面积随时间的变化呈现出α=1.5的幂指数关系,以及该指数大于VonNeumann定律的时间指数的可能原因.讨论了气泡的边数分布及其二阶矩.     

傅立叶变换-主成份分析方法用于二维色谱数据的压缩和重构

结合傅立叶变换（ＦＴ）和主成份分析（ＰＣＡ）技术,实现了二维高效液相色谱数据的压缩和重构,并对不同信噪比的二维色谱测量数据进行了处理,即使对原始数据的压缩比高达２００倍,仍能很好地重构原始数据,当原始数据的信噪比较低时,阈值的选择受大振幅噪音的影响,使压缩比略有下降,但仍然能够保持信号基本不失真。