Reduction of fuel consumption of two rotors axial flow combine harvester

Abstract

The paper presents dynamics of fuel consumption of axial flow combine harvester with two threshing-separation rotors. Studies showed that operating in idle mode, with technological drives switched off, and the rotation frequency of the engine minimized from 2100 to 1200 min-1, fuel consumption is decreased by 21.9 ± 0.19 l h-1. When passing through the stubble with empty grain tank with the rotation frequency of the engine reduced from 2100 to 1000 min-1, fuel consumption of the combine harvester is reduced by 12 l h-1. When the soil is moist and the grain tank is full, the speed of combine harvester travelling through the stubble above 6 km h-1 is considered irrational, as fuel consumption increases following exponential function. The feed-rate of crop flow supplied to the combine harvester has been assumed to be rational when the amount of fuel used for threshing one ton of grains is kept to a minimum, and the grain losses resulting from threshing-separation unit and cleaning shoe are below permissible limit value (0.5%). When harvesting dry winter wheat, spring barley and oat, fuel consumption per ton of grain is kept to a minimum when combine harvester is supplied with the crop flow of 15 to 18 kg s-1. Under the crop flow of 16.6 kg s-1 and with the increased rotation frequency of threshingseparation rotors from 1000 to 1200 min-1, increase in hourly fuel consumption amounts for 16.8 l for harvesting of winter wheat Zentos, and 4.4 l for harvesting of spring barley Baronesse. Increase of the concave clearance from 10 to 14 mm, when combine harvester is supplied with the crop flow of 16.7 kg s-1 of spring barley, enables to reduce hourly fuel consumption by approximately 12 l. When combine harvester is supplied with the crop flow of 16 kg s-1 of winter wheat, and straw is dropped in windrows, its fuel consumption is by 8.0 l h-1 less when compared to chopping and spreading the straw on the stubble. At lower feed-rate, this difference is further reduced