Computer Simulation of the Operation of the Recuperative Swivel Bunk Device of a Hauling Tractor with a Timber Drug

Abstract

The article validates the necessity of increasing the transportation efficiency of longcut timber (LCT) by hauling tractors with timber drugs during their operation in conditions of poorly equipped logging roads with the presence of irregularities, defects, barriers, as well as frequent turns, ascents and descents. An original scheme of a recuperative swivel bunk device (RSBD) for a hauling tractor (HT) with a timber drug (TD) is designed as a result of earlier research on development and evaluation of various recuperative coupling devices for logging trucks operating in difficult road conditions. A computer program has been developed in order to identify the dependences of change in time of such parameters of the bunk device efficiency as recoverable power and horizontal acceleration of an LCT bundle, as well as to determine the regularities of influence of the studied heights of the logging road bearing area, the driving speed of a logging truck and the inner diameter of longitudinal and transverse hydraulic cylinders of the recuperative device on these parameters. It has been found out that equipping a logging truck with the proposed RSBD is reasonable when LCT transporting, especially in conditions of poorly equipped logging roads. With an increase in speed of the logging truck when it moves in difficult road conditions from 10 to 60 km/h recoverable power increases significantly from 3 to 24 kW, as well as the horizontal acceleration of the LCT bundle relative to HT changes from 0.4 to 2.3 m/s2. It is found that the optimum diameters of transverse and longitudinal hydraulic cylinders of RSBD, providing the maximum recoverable power of 6.7 kW and the average horizontal acceleration of the LCT bundle of 1 m/s2, is 50 mm. The results obtained can be useful to research and design organizations engaged in further improvement of recuperative devices of similar type used for timber road transport.