Natural Convection from Circular Cylinders

Natural Convection from Circular Cylinders PDF

Author: Sandra K. S. Boetcher

Publisher: Springer

Published: 2014-08-05

Total Pages: 57

ISBN-13: 3319081322

DOWNLOAD EBOOK →

This book presents a concise, yet thorough, reference for all heat transfer coefficient correlations and data for all types of cylinders: vertical, horizontal, and inclined. This book covers all natural convection heat transfer laws for vertical and inclined cylinders and is an excellent resource for engineers working in the area of heat transfer engineering.

Natural Convection Inside a Horizontal Circular Cylinder

Natural Convection Inside a Horizontal Circular Cylinder PDF

Author: Robert G. Hantman

Publisher:

Published: 1969

Total Pages: 204

ISBN-13:

DOWNLOAD EBOOK →

The work analyzes the natural convection of a fluid contained in an infinitely long horizontal cylinder at large Prandtl number and unit order Grashof number. The motion is generated by an imposed cosine wall temperature distribution which includes an arbitrary phase angle. This phase angle may be varied to allow for cases ranging from heating-from-the-side to heating-from-below to be investigated. From an asymptotic ordering of the governing energy and vorticity transport equations for large Prandtl number, it is shown that the core region, which contains the fluid surrounded completely by a boundary-layer flow along the cylinder wall, may assume either of two configurations. The choice of the core configuration is shown to depend upon the nature of the streamlines therein. Solutions obtained from linearized forms of the full governing equations agree with the core temperature and velocity fields which were observed experimentally for heating angles sufficiently away from the heating-from-the-side case. Also, the influence of various linearizations is studied. For heating angles near the heating-from-the-side case, a linearized form of the boundary layer equations is developed which allows the solutions to match with the second possible core configuration. The form of the results agrees generally with experimental evidence for heating-from-the-side. (Author).

Natural Convection Heat Transfer from a Horizontal Disk in a Cylindrical Enclosure

Natural Convection Heat Transfer from a Horizontal Disk in a Cylindrical Enclosure PDF

Author: Duane Stewart Duncan (Jr)

Publisher:

Published: 1971

Total Pages: 57

ISBN-13:

DOWNLOAD EBOOK →

In the report the author discusses natural convection in water from a horizontal mirror finished disk, heated in the center and surrounded by a cylindrical enclosure. The test section was designed to insure a one dimensional heat flux. Measurements were taken with power inputs varying from 25 to 5 watts. Fluid depth had a definite effect on the heat transfer. An apparent maximum value existed at a ratio of enclosure radius to fluid depth of one. Comparison of the data with existing correlations however, was poor which led to the questioning of the validity of the assummed one dimensional heat flux. Use of a finite element computer program demonstrated that two dimensional effects were important. Subsequent modification of the heat transfer coefficient to account for this variation gave a correlation more in agreement with those existing in the literature. (Author).

Natural Convection Heat Transfer Between Arrays of Horizontal Cylinders and Their Enclosure

Natural Convection Heat Transfer Between Arrays of Horizontal Cylinders and Their Enclosure PDF

Author:

Publisher:

Published: 1984

Total Pages:

ISBN-13:

DOWNLOAD EBOOK →

The natural convection heat transfer between arrays of horizontal, heated cylinders and their isothermal, cooled enclosure was experimentally investigated. Four different cylinder arrays were used: two in-line and two staggered. Four fluids (air, water, 20 cs silicone, and 96% glycerine) were used with Prandtl numbers ranging from 0.705 to 13090.0. There was no significant change in the Nusselt number between isothermal and constant heat flux conditions of the cylinder arrays. The average heat transfer coefficient was most affected by the spacing between cylinders and the total surface area of the cylinder arrays. The enclosure reduced the expected increase in both the average and the local heat transfer coefficients caused by changing the inner body from an in-line arrangement to a staggered arrangement of comparable spacing. An increase in fluid viscosity reduced the influence of the geometric effects.

Natural Convective Heat Transfer from Short Inclined Cylinders

Natural Convective Heat Transfer from Short Inclined Cylinders PDF

Author: Patrick H. Oosthuizen

Publisher: Springer Science & Business Media

Published: 2013-12-11

Total Pages: 133

ISBN-13: 3319024590

DOWNLOAD EBOOK →

Natural Convective Heat Transfer from Short Inclined Cylinders examines a heat transfer situation of significant, practical importance not adequately dealt with in existing textbooks or in any widely available review papers. Specifically, the book introduces the reader to recent studies of natural convection from short cylinders mounted on a flat insulated base where there is an “exposed” upper surface. The author considers the effects of the cylinder cross-sectional shape, the cylinder inclination angle, and the length-to-cross sectional size of the cylinder. Both numerical and experimental studies are discussed and correlation equations based on the results of these studies are reviewed. This book is ideal for professionals involved with thermal management and related systems, researchers, and graduate students in the field of natural convective heat transfer, instructors in graduate level courses in convective heat transfer.