Kinetic model of continuous-wave flow chemical lasers

In this paper an analysis of the kinetic theory of the continuous-wave flow chemical lasers(CWFCL) is presented with emphasis being laid on the effects of inhomogeneous broadeningon CWFCL's performance. The results obtained are applicable to the case where laser fre-quency is either coincident or incoincident with that of the eenter of the line shape. This rela-tion has been,compared with that of the rate model in common use. These two models are almostidentical as the broadening parameter η is larger than 1. The smaller the value of η, thegreater the difference between the results of these two models will be. For fixed η, the dif-ferences between fhe results of the two models increase with the increase of the frequencyshift parameter ξ. When η is about less than 0.2. the kinetic model can predict exactly the in-homogeneous broadening effects,while the rate model cannot.

Flow pattern in chandler loop - the artificial thrombus formation

In this paper a hydrodynamic approach is used to analyse carefully the flow field inChandler loop--the artificial thrombus formation. The results obtained show that near thelower meniscus where the thrombus is formed, there is a back flow accompanied with asecondary flow and its mainflow is toward the meniscus, thus providing a favourable condi-tion for corpuscle aggregation. Our finding is valuable for studying the mechanism ofthrombus formation in artificial organ and in vivo.

Coupled deformation-flow analysis for methane hydrate production by depressurized wells

A formulation for coupled flow-deformation analysis of methane-hydrate extraction problems is presented. By assuming that the hydrate does not flow, a two phase flow formulation is considered, based on Darcy's law and capillary pressure relation. The formulation is implemented in the finite difference code FLAC. The code was used to investigate the stability of a methane extraction well by depressurizing the well. © 2005 Taylor & Francis Group, London.

非极性小分子有机液体在微管道中的流量特性

用去离子水及有机液体在内径约为25μm的石英圆管内进行了流量特性实验。液体分子量范围为18～160，动力黏性系数的范围为0.5～1 mPa·s。实验雷诺数范围为Re < 8。所用有机液体为：四氯化碳、乙基苯及环乙烷都是非极性液体，其分子结构尺度小于1nm。实验结果表明，在定常层流条件下，圆管内的液体流量与两端压力差成正比，其压力-流量关系仍符合经典的Hagen-Poiseuille流动。这说明非极性小分子有机液体在本实验所用微米尺度管道中其流动规律仍符合连续介质假设。鉴于微尺度流动实验的特殊性，文中还介绍了微流动实验装置，分析了微尺度流动测量误差来源及提高测量精度的措施。