Download or read book The Influence of Fin Height and Wall Conductivity on Integral fin Tubes During Steam Condensation written by David William Meyer and published by . This book was released on 1994 with total page 151 pages. Available in PDF, EPUB and Kindle. Book excerpt: Heat transfer performance of horizontal, integral-fm tubes made of copper, aluminum, copper-nickel, and stainless steel was evaluated using a boiler and steam condenser assembly. Testing was done at vacuum and atmospheric pressure conditions. The tubes tested had an inner diameter of 12.7mm, a root diameter of 13.88mm, and fin heights ranging from 0.5mm to 1.5mm, in 0.25mm increments. The outside heat transfer coefficient was determined first by finding the overall heat transfer coefficient, Uo, then by using the Modified Wilson Plot Technique. The results indicated that the performance of a finned tube is very dependent on fin height and tube material. Moreover, the results were compared with the predictive models of Beatty and Katz, Rose, Adamek and Webb, and Honda et al., with a modified version of the Rose model demonstrating the best predictive capabilities.
Download or read book The Influence of Wall Conductivity on Film Condensation with Integral Fin Tubes written by Robert Lee Cobb and published by . This book was released on 1993 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt: Heat transfer performance of steam condensing on horizontal finned tubes made of copper, aluminum, copper nickel(90/10), and stainless steel(316) was studied using a condenser test rig at both vacuum and atmospheric conditions. Integral fin tubes included conventional rectangular shaped fins as well as rectangular fins having a radiussed root geometry (ie, a fillet radius equal to half the fin spacing). All finned tubes had inner and outer diameters of 12.70mm and 15.88mm respectively, and had a fin thickness of l.0mm and a fin spacing of 1.5mm. The overall heat transfer coefficient (U sub o) was determined experimentally and the outside heat transfer coefficient (ho) was obtained utilizing a modified Wilson Plot procedure. Results indicated that the performance of a finned tube was strongly dependent on the tube material and weakly dependent on fin geometry. Radiussing the fin root to remove condensate between fins in the unflooded portion (ie, top portion) of a finned tube reduced the heat transfer performance compared to a conventional rectangular shaped integral fin. Experimental data were compared to the models of Beatty and Katz as well as to a modified model of Rose.
Download or read book The Influence of Wall Conductivity on Film Condensation with Integral Fin Tubes written by Robert Lee Cobb and published by . This book was released on 1993 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Heat transfer performance of steam condensing on horizontal finned tubes made of copper, aluminum, copper nickel(90/10), and stainless steel(316) was studied using a condenser test rig at both vacuum and atmospheric conditions. Integral fin tubes included conventional rectangular shaped fins as well as rectangular fins having a radiussed root geometry (ie, a fillet radius equal to half the fin spacing). All finned tubes had inner and outer diameters of 12.70mm and 15.88mm respectively, and had a fin thickness of l.0mm and a fin spacing of 1.5mm. The overall heat transfer coefficient (U sub o) was determined experimentally and the outside heat transfer coefficient (ho) was obtained utilizing a modified Wilson Plot procedure. Results indicated that the performance of a finned tube was strongly dependent on the tube material and weakly dependent on fin geometry. Radiussing the fin root to remove condensate between fins in the unflooded portion (ie, top portion) of a finned tube reduced the heat transfer performance compared to a conventional rectangular shaped integral fin. Experimental data were compared to the models of Beatty and Katz as well as to a modified model of Rose.
Download or read book Effect of Fin Height on Film Condensation of Steam on Stainless Steel Integral fin Tubes written by George A. Incheck and published by . This book was released on 1995 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Condensation heat transfer performance on a series of horizontal stainless-steel integral-fin tubes was experimentally studied at both atmospheric and vacuum pressure conditions to examine the effects of fin height on tubes of low thermal conductivity. Eight tubes with rectangular fin heights ranging from 0.16 to 1.42 mm and a smooth tube were tested. The fin thickness and spacing and tube inside and root diameters were kept constant at 1.0, 1.5, 13.1, and 14.2 mm respectively. The overall heat transfer coefficient was determined from experimentation and the outside heat transfer coefficient was then determined using the modified Wilson plot technique. A fin height of approximately 0.30 mm provided the maximum heat transfer at both vacuum and atmospheric conditions. Heat transfer performance declined steadily for further increases in fin height. The experimental results were compared to the predictions of the Beatty and Katz and Briggs and Rose models. Neither model satisfactorily predicted performance for the full range of fin heights tested.
Download or read book Effect of Fin Height on Film Condensation of Steam on Stainless Steel Integral fin Tubes written by George A. Incheck and published by . This book was released on 1995 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt: Condensation heat transfer performance on a series of horizontal stainless-steel integral-fin tubes was experimentally studied at both atmospheric and vacuum pressure conditions to examine the effects of fin height on tubes of low thermal conductivity. Eight tubes with rectangular fin heights ranging from 0.16 to 1.42 mm and a smooth tube were tested. The fin thickness and spacing and tube inside and root diameters were kept constant at 1.0, 1.5, 13.1, and 14.2 mm respectively. The overall heat transfer coefficient was determined from experimentation and the outside heat transfer coefficient was then determined using the modified Wilson plot technique. A fin height of approximately 0.30 mm provided the maximum heat transfer at both vacuum and atmospheric conditions. Heat transfer performance declined steadily for further increases in fin height. The experimental results were compared to the predictions of the Beatty and Katz and Briggs and Rose models. Neither model satisfactorily predicted performance for the full range of fin heights tested.
Download or read book Condensation on Integral fin Tubes written by and published by . This book was released on 1995 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Some Aspects of Film Condensation of Steam on Finned Tubes written by James M. Coumes and published by . This book was released on 1989 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: Heat-transfer measurements were made for filmwise condensation of steam on smooth tubes and finned tubes with rectangular-shaped fins. The influence of fin root diameter on a single horizontal finned tube was examined by taking data for two families of tubes whose fin root diameters were 12.7 and 19.05 mm. Each family of tubes had fins that were 1 mm thick and 1 mm high, but with fin spacings of 0.25, 0.50, 1.0, 1.5, 2.0, and 4.0 mm. To compare results being obtained in a concurrent research project with Queen Mary College (University of London), data were collected on two tubes whose fin root diameters were 12.7 mm, and which had fin thickness of 0.5 mm, fin heights of 1.59 mm, and fin spacings of 1.0 mm. A comparison of the enhancement ratios (based on constant vapor-side temperature drop) with past Naval Postgraduate School (nps) studies showed good agreement. The apparatus was then modified in order to study the effects of condensate inundation.
Download or read book Filmwise Condensation of Steam on Low Integral Finned Tubes written by Ioannis V. Georgiadis and published by . This book was released on 1984 with total page 167 pages. Available in PDF, EPUB and Kindle. Book excerpt: Filmwise condensation heat-transfer measurements of steam were made on horizontal tubes under vacuum and near-atmospheric pressures. Data were taken for smooth tube and for 21 tubes which contained rectangularly-shaped, low integral fins. The fin geometry was systematically varied in order to investigate the dependence of the steam-side heat-transfer coefficient on fin spacing, thickness and height. The condensation process was found to be most sensitive to fin spacing and to be weakly dependent on fin thickness. When the fin height was increased from 1.0 to 2.0 mm, the increase in the heat-transfer coefficient was about 20 percent, while the increase in condensing area was 51 percent. The best performing finned tube had a fin height of 1.5 mm, a fin thickness of 1.0 mm and a fin height of 2.0 mm. It showed an enhancement over the smooth tube of between 4 to 5 under vacuum conditions and around 6 at atmospheric conditions. Thus, the use of finned tubes may result in a significant reduction in size and weight of present-day steam condensers. Originator-supplied key words include: Steam, Condensation, Filmwise, Tube, Low Integral Fin, Heat-Transfer Coefficient, Enhancement.
Download or read book Extended Surface Heat Transfer written by Allan D. Kraus and published by John Wiley & Sons. This book was released on 2002-03-14 with total page 1120 pages. Available in PDF, EPUB and Kindle. Book excerpt: Drei anerkannte Experten dieses schnellebigen, modernen Fachgebiets erläutern hier Theorie, Design und Anwendungen eines breiten Spektrums von Oberflächen, die speziell für den effizienten Wärmetransport ausgelegt sind. Behandelt werden u. a. kompakte Wärmetauscher, periodische Wärmeströme und Siedevorgänge an Kühlrippen. Umfassend und informativ!
Download or read book Government Reports Annual Index written by and published by . This book was released on 1994 with total page 1744 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1968 with total page 700 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Film Condensation of Steam on Externally Finned Horizontal Tubes written by Frederick A. Flook and published by . This book was released on 1985 with total page 147 pages. Available in PDF, EPUB and Kindle. Book excerpt: Filmwise condensation measurements of steam were made on horizontal finned tubes under vacuum and near-atmospheric conditions. Data were obtained for copper tubes with fins of rectangular, triangular, trapezoidal, and parabolic cross sections, and for a commercially-available finned tube. A stainless steel finned tube was also tested to investigate the effect of thermal conductivity. Maximum enhancements of about 4.8 were obtained under vacuum conditions, and about 6.9 at atmospheric pressure, compared to a smooth tube having an outside diameter equal to the root diameter of the finned tubes. The optimum fin spacing was found to be about 2.0 mm for rectangularly shaped-fins with a fin-thickness of 1.0 mm, and fin height of 0.5 and 1.5 mm. Fins with a parabolic shape were shown to perform better than fins of rectangular shape, and fins were shown to degrade the performance of stainless steel tubes. The effects of vapor shear were also shown to have only a small influence on the steam-side heat transfer coefficient. A theoretical model proposed by Webb et al. was found to underpredict the experimental data. Several suggestions to modify this model are described. Keywords: External fin; Heat transfer coefficient; Enhancement, Condenser tubes (Theses).
Download or read book Heat Transfer 1986 written by Chang L. Tien and published by CRC Press. This book was released on 1986-09-01 with total page 370 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Film Condensation of Steam on Externally Finned Horizontal Tubes written by and published by . This book was released on 1985 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Filmwise condensation measurements of steam were made on horizontal finned tubes under vacuum and near-atmospheric conditions. Data were obtained for copper tubes with fins of rectangular, triangular, trapezoidal, and parabolic cross sections, and for a commercially-available finned tube. A stainless steel finned tube was also tested to investigate the effect of thermal conductivity. Maximum enhancements of about 4.8 were obtained under vacuum conditions, and about 6.9 at atmospheric pressure, compared to a smooth tube having an outside diameter equal to the root diameter of the finned tubes. The optimum fin spacing was found to be about 2.0 mm for rectangularly shaped-fins with a fin-thickness of 1.0 mm, and fin height of 0.5 and 1.5 mm. Fins with a parabolic shape were shown to perform better than fins of rectangular shape, and fins were shown to degrade the performance of stainless steel tubes. The effects of vapor shear were also shown to have only a small influence on the steam-side heat transfer coefficient. A theoretical model proposed by Webb et al. was found to underpredict the experimental data. Several suggestions to modify this model are described. Keywords: External fin; Heat transfer coefficient; Enhancement, Condenser tubes (Theses).
Download or read book Two Phase Heat Transfer Enhancement written by Sujoy Kumar Saha and published by Springer. This book was released on 2019-07-04 with total page 121 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Brief concerns heat transfer and pressure drop in heat transfer enhancement for boiling and condensation. The authors divide their topic into six areas: abrasive treatment and coatings, combined structured and porous surfaces, basic principles of boiling mechanism, vapor space condensation, convective vaporization, and forced condensation inside tubes. Within this framework, the book examines range of specific phenomena including abrasive treatment, open grooves, 3D cavities, etched surfaces, electroplating, pierced 3D cover sheets, attached wire and screen promoters, non-wetting coatings, oxide and ceramic coatings, porous surfaces, structured surfaces (integral roughness), combined structured and porous surfaces, composite surfaces, single-tube pool boiling tests, theoretical fundamentals like liquid superheat, effect of cavity shape and contact angle on superheat, entrapment of vapor in cavities, nucleation at a surface cavity, effect of dissolved gases, bubble departure diameter, bubble dynamics, boiling hysteresis and orientation effects, basic principles of boiling mechanism, visualization and mechanism of boiling in subsurface tunnels, and Chien and Webb parametric boiling studies.
Download or read book Naval Research Reviews written by and published by . This book was released on 1986 with total page 620 pages. Available in PDF, EPUB and Kindle. Book excerpt:
