集管系统压力与流量分布的研究(II)——Z型布置时的分析解

建立了Z型布置时集管系统压力与流量分布的数学模型 ,在对微分方程进行无量纲化的过程中导出了一个重要的综合性无量纲性能参数。方程解的结果表明利用这个综合参数可以快速确定在联箱摩擦阻降相对很小条件下集管系统的流量分布状态和总压降 ;对集管系统采用Z型与U型布置导致的流量分布特性的差异作了分析 ;解的结果对压力恢复型集管系统的设计和性能预测具有指导意义     

集管系统压力与流量分布的研究（II）—Z型布置时的分析解

建立了Z型布置时集管系统压力与流量分布的数学模型,在对微分方程进行了无量纲化的过程中导出了一个重要的综合性无量纲性能参数,方程解的结果表明利用这个综合参数可以快速确定在联箱摩擦阻降相对很小条件下集管系统的流量分布状态和总压降,对集管系统采用Z型与U型布置导致的流量分布特性的差异作了分析,解的结果对压力恢复型复集系统的设计和性能预测具有指导意义。     

油品管线集肤加热系统的研究与可行性分析

介绍了集肤电流加热系统的形式、组成,并对发热原理进行了分析,提出了该方法利用国产设备和材料的可行性。     

并联管组流量分配规律的研究

综合评述了国内外单相流体在并联管组中流量分配方面的研究工作,归纳总结了研究并联管组流量分配的理论基础及计算方法,分析研究了集箱中的摩擦系数和动量交换系数等有关并联管组流量分配的基础性实验数据及今后的研究方向。     

并联管组内流量均匀分布的数学模型

为解决并联管组中流体流量分布不均的问题,提出改变集管内局部阻力配置的方法,建立了基于动量衡算法的流量均布离散化数学模型,利用解析法求解得到阻力配置的通用公式,并根据公式计算所得的加阻位置和阻力系数在太阳能集热器阵列上进行试验验证.结果表明:即使存在由于简化假设和参数近似拟合而导致的诸多误差,增加恰当的阻力元件仍可使流量分布不均匀度下降一个数量级,最大流量与最小流量之比从约等于7降至1.5以下,流量分布改善效果明显.     

3-Dimensional current distribution in the nozzle of an MHD channel

The nozzle has been idealized by retaining only its salient feature, the accelerated motion of the fluid. Analytical solutions of the current distributions have been obtained and plotted. High current concentrations can be avoided by allowing a net current flow through an appropriate electrical connection to the nozzle and by minimizing the turbulence in the fluid flow.     

The Analytical Approximate Solution of the 2D Thermal Displacement

The 2D plane gas flow under heating (with nonentity boundary condition) has been discussed by the analytical approach in this paper. The approximate analytical solutions have been obtained for the flow passing various kinds of heat sources. Solutions demonstrate the thermal displacement phenomena are strongly depend on the heating intensity.     

Analytical Solution of Thermocapillary Flow in Cylindrical Annuli with Curved Free Surface

In this paper we consider thermocapillary flow with interface deformation in cylindrical annuli subjected to lateral temperature gradient. Based on the assumption that Reynolds, Marangoni and capillary numbers are very small, we expanded the governing equations in terms of a small parameter, and the zeroth-order one is the Stokes problem, which can be analytically solved by use of separation of variables formulation. Solutions are obtained for the zeroth-order fluid and thermal fields as well as...     

圆管紊流光滑区纵向离散解析解

用Ｔａｙｌｏｒ对扩散方程的简化处理及Ｎｉｋｕｒａｄｓｅ的国管紊流光滑区流速指数分布，研究了国管紊流光滑区的纵向离散，给出了截面浓度亏损及纵向离散系数的解析表达式．它对完善环境水力学学科的示踪质纵向离散研究具有一定的备论意义     

圆形断面隧洞衬砌内力分布的解析计算模型

隧洞衬砌的内力计算有不同方法,重点讨论了软基土中圆形隧洞衬砌内力的计算方法。根据均质圆形隧洞围岩压力对称周期性变化以及衬砌结构微元体轴向力和弯矩的静力平衡方程,分析得到了衬砌内力的解析表达式。并将解析分析结果与实测结果进行了对比分析。     

Slug flow heat transfer in a semi‐infinite microtube with temperature jump wall condition

This paper presents an analytical solution of steady‐state heat transfer for laminar, two‐dimensional, and rarefied gas flow in a semi‐infinite microtube. To account for the slip‐flow characteristics of microscale heat transfer, temperature jump condition at the wall has been included in the model while the fluid velocity is assumed to be constant (slug flow). The solution yields closed form expressions for fully‐developed Nusselt numbers in terms of Knudsen number and Prandtl number under both isothermal and isoflux wall conditions. © 2009 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20263     

Unsteady squeezing flow of water‐based nanofluid between two parallel disks with slip effects: Analytical approach

The squeezing flow of an unsteady water‐based nanofluid between two parallel disks has been analyzed in the current study. Thermal and solutal buoyancy along with heat source enhance the flow phenomena of free convective flow through a porous medium. In addition to that velocity slip and temperature slip are also accounted for in the boundary conditions. The similarity transformation is adopted to formulate the governing equations that convert the complex partial differential equations (PDEs) to nonlinear ordinary differential equations (ODEs). These transformed equations are handled analytically by using the variation parameter method (VPM). For computational purposes, the fixed numeric values of physical parameters are used and their behaviors are shown by means of graphs. The calculated results for the physical quantities of interest are shown in tables. The conformity of the solution is obtained in comparison to an earlier study in a particular case. The major findings are (i) the velocity profile has distinct variations, which are separated by the middle layer of the channel and (ii) enhancement in the heat transfer coefficient is noted due to the interaction of buoyancy parameter.