热传导方程的C-N格式区域分解方法及其稳定性分析     

任丽丽  朱少红  赵凤柱 《唐山师范学院学报》2011,33(2):36-38

基于C-N格式提出了热传导方程区域分解的并行差分方法。该方法在子区域的边界处采用古典显格式计算,在子区域内部使用C-N格式进行求解。对算法进行了稳定性分析,得到稳定性条件为r〈1。  相似文献   

管壳式换热器复合形法优化设计     

曾宏  叶长燊 《泉州师范学院学报》2011,29(6):39-44

基于无相变传热过程,建立管壳式换热器优化设计的数学模型．模型以年总费用为目标函数,关联传热面积的非线性方程,适宜采用多变量约束的复合形法．工艺计算结果表明：该模型符合工程实际,复合形法完全可用于该文模型的优化求解．  相似文献   

Field evaluation of a ground-coupled heat pump in hot-summer and cold-winter regions     

LEI Fei  HU Ping-fang  SUN Qi-ming  JIANG Zhang-ning 《重庆大学学报(英文版)》2011,10(4):159-167

The experimental performance of small-sized ground-coupled heat pump (GCHP) is researched intensively. However, there are little data documenting the operation performance of existing large-sized GCHP system. We presented the actual performance measurement of a GCHP installed for apartment buildings in Wuhan, Hubei province, P. R. China. The system was constructed with a closed vertical typed ground heat exchanger with a total pipe length of 32 000 m. During one year, various operating parameters were monitored, including the outdoor temperature, the flow rate, the electrical consumption, and the water temperature. The seasonal coefficients of performances of the heat pumps and the system based on the measured data were found to be 4.01 and 2.96 in the cooling season, and 3.54 and 2.86 in the heating season, respectively. The GCHP system was more economical than the air-source room air conditioner in the energy efficiency which was increased by 29 in cooling mode and 50 in heating mode. There was an obvious heat imbalance of soil between the injection rate and the extraction rate in the residential GCHP system operation.  相似文献   

基于泊松与分形分布研究池沸腾临界热流密度     

肖波齐  陈炳强 《三明学院学报》2011,28(2)

基于加热表面核化点遵循泊松与分形分布,提出了临界热流密度的一个数学模型,从该模型中发现大空间临界热流密度(CHF)是壁面过热度、接触角和流体物理特性的函数.对不同的接触角,模型预测的结果与实验数据进行了比较.两者很好地吻合.  相似文献   

Heat transfer properties and chaotic analysis of parallel type pulsating heat pipe     

史维秀  李惟毅  潘利生  谈西峰 《天津大学学报(英文版)》2011,17(6):435-439

The refrigerant mixture of ethanol aqueous was applied to the parallel type pulsating heat pipe (PHP). The operation characteristics of the PHP were analyzed by means of experiment and nonlinear chaotic theory. Moreover, the relationship between the running state and attractor was described. The results indicate that starting power, stable running power and dry burning transition power are about 64.08 W, 148.68 W and 234.0 W respectively. The cycle and amplitude of PHP initially decrease and then increase with the increasing power. However, the data are welldistributed in a certain range. The running state is in agreement with the attractors, and the changing process for attractors is as follows: the attractors first disperse in the whole phase space, then present mass status, and finally show band distribution.  相似文献   

江淹诗论说     

颜建华 《贵阳学院学报(社会科学版)》2002,(3)

江淹的诗歌有的意象奇崛峭拔 ,有的具有悲壮凄凉之气 ,有的基调沉郁而朴茂遒劲。其仿拟之作 ,大多达到貌合神似的地步。他的《清思诗五首》表现出超尘脱俗的境界 ,显得空灵飘逸。《悼室人十首》抒写诗人难以抑制的悲痛和伤感 ,情感哀婉缠绵。在永明诗风盛行的南朝 ,江淹的诗歌可谓独树一帜 ,钟嵘《诗品》评价为“诗体总杂 ,善于模拟” ,刘熙载《艺概》论云 :“有凄凉日暮不可如何之意” ,在诗美和诗境上别具特色。但模拟毕竟非作家自身本色。江淹在诗思上不可避免地受到羁制 ,欠缺深刻的笔力。  相似文献   

相对论变换下热力学系统热量及温度变换关系的另一种推证     

潘营利 《渭南师范学院学报》2005,20(5):29-31

文章给出了相对论情况下热力学系统从一个惯性系到另一个惯性系时热量及温度变换关系的另一种推证方法.从而支持了奥特的结果,否定了普朗克的结果.  相似文献   

螺旋折流片强化管壳式换热器内管束传热数值模拟     

陈亚平  梅娜  施明恒 《东南大学学报》2007,23(1):81-85

介绍了一种用于强化管壳式换热器壳侧传热和支撑管束的螺旋折流片新型结构,该结构是对换热器管子相间地套上螺旋折流片以产生旋涡流动.研究模型是在正方形布置的4个管子中的2个对角管子套上螺旋折流片后形成的通道,利用FLUENT软件对该上述四管通道模型的流场和温度分布情况进行了数值模拟;分析了四管通道模型中螺旋折流片对强化传热和流动阻力随雷诺数的变化关系的影响.算例结果显示该新型结构可比相同尺寸的光管通道中的情形传热系数提高约40%～55%,同时也将伴随较高的流动阻力.可以相信螺旋折流片式换热器将会在许多工业领域有良好的应用前景.  相似文献   

多调和算子Dirichlet特征值下界的一种估计     

刘庆辉 《唐山师范学院学报》2007,29(5):52-54

通过构造热核函数的部分和,我们给出了多调和算子Dirichlet特征值的一个新的下界估计,新的估计式推广了已有的特征值估计的结果。  相似文献   

热力学第二定律研究方法的评述     

于津江 《石家庄学院学报》2001,3(2):45-46

通过对热力学第二定律详细分析,从不同角度讨论了准静态绝热过程的微分方程,在对微分方程进行积分的过程中指出积分因子不是唯一的.  相似文献