Abstract
The effect of a number of variables on heat transfer from town gas flames to horizontal water jacketed tubes was investigated. Aerated and non-aerated flames inside 2.00" and 4.16" internal diameter tubes were studied. The variables were as follows:- The total heat transfer rate was obtained from the flow rate and temperature rise of the water in the jackets. An estimate of the radiant heat transfer was made by means of radiation pyrometer measurements. Pressure loss was also studied. The results were correlated by analysis of variance and it was found that overall heat transfer was dependent on heat input, tube length, % Excess air and tube diameter only. Little difference was found between aerated and non-aerated flames, and the results for these two could be combined with little sacrifice of accuracy. The recommended equations for % overall thermal efficiency are:- n= 72.77 +59.53 log L -0.4865 L log E -5.683 log E -45.51 log R +22.62 log D s.d. = 4.4, or with a slight sacrifice of accuracy:- n= 83.47 +67.99 log L -9.540 log E -45.70 log R +21,02 log D s.d. = 4.5 The results of a previous worker were incorporated in these equations.