| Popis: |
An experimental technique which is often used to study convective heat transfer by investigating analogous naphthalene sublimation situations requires a knowledge of the diffusion coefficient of naphthalene into air to couple the two systems. Only two previous measurements of the diffusion coefficient have appeared in the literature (Mack, J. Am. Chem. Soc. 47 , 2468–2482 (1925) and Caldwell, J. Chem. Engng Data 29 , 60–62 (1984)). Both measurements were taken at single but different temperatures and their values differed by approximately 29%. In view of this uncertainty, an experiment was performed to measure the diffusion coefficient of naphthalene into air over the temperature range 15°C ⩽ T ⩽ 55°C. Two different geometrical systems were used as a check on possible systematic errors. The repeatability of the data is 2% and the estimated possible systematic error is ±3%. The data result in Schmidt and Lewis numbers which have a weak temperature of 25°C. |
