首页   按字顺浏览 期刊浏览 卷期浏览 TRANSVERSE LAMINAR FLOW OF NON-NEWTONIAN FLUIDS OVER A BANK OF LONG CYLINDERS
TRANSVERSE LAMINAR FLOW OF NON-NEWTONIAN FLUIDS OVER A BANK OF LONG CYLINDERS

 

作者: A. TRIPATHI,   R. P. CHHABRA,  

 

期刊: Chemical Engineering Communications  (Taylor Available online 1996)
卷期: Volume 147, issue 1  

页码: 197-212

 

ISSN:0098-6445

 

年代: 1996

 

DOI:10.1080/00986449608936504

 

出版商: Taylor & Francis Group

 

关键词: Pressure drop;Non-Newtonian flow;Fibrous beds;Cylinders;Drag coefficient

 

数据来源: Taylor

 

摘要:

The creeping transverse flow of incompressible Carreau model fluids past an array of infinitely long cylinders has been analysed theoretically. The hydrodynamic interactions between cylinders have been simulated using a simple cylinder-in-cylinder free surface cell model. In this formalism, the overall mean porosity characterises an array of cylinders without any assumption regarding the actual geometrical arrangement of the individual cylinders. The resulting non-linear field equations have been solved approximately by employing the well known velocity and stress variational principles. The resulting upper and lower bounds are non-coincident and diverge increasingly with the rising extent of non-Newtonian behaviour of the liquid medium. However, the mean value of the drag coefficient deviates from the individual bounds by no more than 22% and therefore, the use of the arithmetic mean of the upper and lower bounds is suggested. The theoretical predictions reported herein encompass wide ranges of physical and kinematic conditions as follows: 1 ≥n≥ 0.2; 0.9 ≥ ϵ ≥ 0.3 and ∧ ≤ 500. The paper is concluded by presenting comparisons between the present predictions and the scant experimental results for two limiting cases, namely, for the flow of Newtonian fluids (n= 1) through assemblages of solid rods and random fibrous beds, and for the flow of power law liquids (i.e., for large values of ∧) through banks of rods. The correspondence is found to be satisfactory.

 

点击下载:  PDF (478KB)



返 回