Calculation of the maximum energy saturation of an agri-cultural tractor

Abstract

The efficiency -f the machine-tract-r unit increases with the increase -f the energy saturati-n -f the tract-r. There-f-re, it is -f interest t- determine the maximum energy saturati-n and the c-rresp-nding tracti-n characteristics -f the tract-r with an estimate -f its efficiency in terms -f pr-ductivity and fuel c-nsumpti-n when c-mpared with the anal-g. With increasing energy saturati-n, the w-rking speed -f the tract-r and the tracti-n resistance -f the w-rking element -f the unit increase, hence the fuel c-nsumpti-n is increased. This circumstance must be taken int- acc-unt in the calculati-n. Determinati-n -f the maximum energy saturati-n -f the tract-r, taking int- acc-unt speed limits and skidding, is an actual task -f the tract-r the-ry. The purp-se -f the study is t- devel-p a meth-d-l-gy and al-g-rithms f-r calculating the maximum energy saturati-n -f the tract-r and its c-rresp-nding tracti-n perf-rmance when the engine speed is changed. The -bject -f investigati-n is a general purp-se wheeled tract-r. S-urce material: engine and tract-r perf-rmance characteristics; c-efficients that characterize the tracti-n and c-upling pr-perties -f the tract-r; the tract-r p-wer balance equati-n; slipping functi-n; the functi-n -f fuel c-nsumpti-n -f the engine and its t-rque fr-m the speed -f the crankshaft. The meth-d -f investigati-n is the calculati-n by the basic f-rmulas -f the the-ry -f the tract-r when the r-tati-nal speed -f the crankshaft is changed by -ne turn-ver. Gear rati-s -f the transmissi-n, calculated taking int- acc-unt the set values -f the n-minal engine speed and the c-efficient -f its adaptability f-r t-rque, are used. Main c-nclusi-ns: a criteri-n f-r the -ptimality -f the den-minat-r -f a number -f gears is pr-p-sed, taking int- acc-unt the c-efficient -f adaptability -f the engine f-r the t-rque; in the tracti-n characteristics -f the tract-r intr-duced additi-nal indicat-rs: the c-efficients -f per-hectare fuel c-nsumpti-n, pr-ductivity and h--k c-nsumpti-n -f fuel per unit -f pr-ductivity; the criteri-n f-r calculating the maximum energy saturati-n is the maximum tracti-n efficiency at the maximum tractive p-wer and the efficiency fact-r in the c-rresp-nding gear with the the-retical speed assumed -n it.