The implementation of an energy recovery system for retreiving otherways wasted energy is an effective method for reducing the overall energy consumption of a mobile machine. In a fork lift, there are two subsystems that can be effectively modified for recovering energy. These are the driveline and the lift/lower function of the mast. This study focuses on the latter by studying a recovery system whose main component is a hydraulic transformer consisting of a hydraulic motor, a variable displacement pump and an induction motor. Since the flow rate/pressure -ratio can be modified, the utilization of the hydraulic transformer enables downsizing of the accumulator volume. However, the decrease of the gas volume leads to an increase in the compression ratio of the accumulator, which in terms leads to higher gas temperatures after charging and consequently to higher thermal losses during holding phase. In order to reduce these losses, a thermally regenerative unit was implemented to the gas volume of an accumulator to reduce the temperature build up during charging. In this study, the effect of improving the thermal characteristics of the accumulator to the efficiency of the whole energy recovery system is investigated by means of measurements.
|Title of host publication||Proceedings of the 10th International Conference on Fluid Power (IFK)|
|Subtitle of host publication||8 - 10 March 2016, Dresden, Germany|
|Publication status||Published - 2016|
|MoE publication type||D3 Professional conference proceedings|
|Event||International Fluid Power Conference - Dresden, Germany|
Duration: 8 Mar 2016 → 10 Mar 2016
Conference number: 10
|Name||International Fluid Power Conference|
|Conference||International Fluid Power Conference|
|Period||08/03/2016 → 10/03/2016|
Hänninen, H., Juhala, J., Kajaste, J., & Pietola, M. (2016). Hydraulic Energy Recovery System Utilizing a Thermally Regenerative Hydraulic Accumulator Implemented to a Reach Truck. In Proceedings of the 10th International Conference on Fluid Power (IFK): 8 - 10 March 2016, Dresden, Germany (Vol. Volume 1, pp. 547-558 ). (International Fluid Power Conference). TU Dresden.