LPG burners for weed control

This article reports on the results of a study carried out on three prototypes of open flame burners for thermal weed control. Their performance is reported in terms of flame temperature and length, in order to ascertain the best ratio between primary and secondary air, and liquefied petroleum gas (LPG) consumption. To find the best ratio between primary and secondary air, the length and temperature of the flame were recorded for each of the three burners, examined by varying the inlet sections of the primary air and secondary air. The data on temperature and the flame length of each burner were processed using multiple regression analysis. The LPG consumption was determined with one of the burners using 10 different pressures in combination with three nozzles. The data obtained were subjected to non-linear regression using two gaseous outflow models. The various combinations of primary and secondary air inlet sections affected the values of the flame length and temperature. In general, the best combinations of primary and secondary air inlet for flame temperature did not correspond to those for flame length. However, this experiment showed that the inlet of secondary air is critical for the performance of this type of burner, in terms of flame temperature. The fuel consumption trial showed that the model proposed for the gaseous outflow is suitable for describing the values of LPG consumption collected during the trial. © 2015 American Society of Agricultural and Biological Engineers.