Temperature profiles for turbulent flow of air in a pipe—II The thermal entrance region

✍ Scribed by R.E. Johnk; T.J. Hanratty

• Publisher: Elsevier Science
• Year: 1962
• Tongue: English
• Weight: 955 KB
• Volume: 17
• Category: Article
• ISSN: 0009-2509
• DOI: 10.1016/0009-2509(62)87020-1

✦ Synopsis

By using a specially designed probe mechanism which entered the system through the pipe outlet and which could be located quite accurately at any radial or longitudinal position in the pipe an extensive set of measurements was made of the temperature profiles in the heat-transfer entry section of an electrically heated pipe through which turbulent air was flowing. The results are compared with the theoretical approaches of DEI~SLER and of SPARROW et al. and with calculations for a homogeneous turbulent field with uniform velocity. The approach of SPARROW et al. should give an accurate description of the temperature field at distances into the heat-transfer section greater than about three pipe diameters if a Reynolds-number-dependent fully developed temperature relation is used. The accuracy of the measurements close to the wall is insufficient to allow any definite statement to be made regarding the prediction of temperature profiles for smaller longitudinal distances.