A solution to the cooling and preheating of hydraulic system by organic Rankine cycle with heat pump
Autor: | Zhengzhao Gu, Zhixin Dong, Xiaogang Zhang, Long Quan |
---|---|
Rok vydání: | 2019 |
Předmět: |
Organic Rankine cycle
Regenerative cooling Renewable Energy Sustainability and the Environment Thermodynamic equilibrium business.industry 020209 energy Energy Engineering and Power Technology 02 engineering and technology law.invention Excavator Fuel Technology 020401 chemical engineering Nuclear Energy and Engineering Operating temperature law 0202 electrical engineering electronic engineering information engineering Environmental science Working fluid 0204 chemical engineering Hydraulic machinery Process engineering business Heat pump |
Zdroj: | Energy Conversion and Management. 180:94-105 |
ISSN: | 0196-8904 |
DOI: | 10.1016/j.enconman.2018.10.097 |
Popis: | The operating temperature of hydraulic oils should be controlled within a reasonable range to keep hydraulic systems in good working condition. However, due to the huge energy losses of hydraulic systems, the oil temperature will increase rapidly. In addition, some hydraulic equipment often operate in cold weather conditions. The conventional cooling with radiators and preheating with electric heaters will consume extra energy for hydraulic systems. Therefore, an organic Rankine cycle with heat pump system is proposed to achieve regenerative cooling and energy-efficient preheating. The system can operate in two modes: an organic Rankine cycle mode to produce electricity instead of consuming energy while cooling the hot oil, and a heat pump mode to preheat the oil with less energy before the hydraulic system starts up in a cold environment. The system is applied to a 260-ton hydraulic excavator to investigate the technical feasibility. On average, the calorific power of the excavator is 177 kW at 245 kW of consumed power in a typical cycle. Considering the cost of heat source, the earning of equilibrium temperature is proposed to evaluate the benefit of the organic Rankine cycle. The optimal working fluid is selected by comparing the system performance. Afterward, the peak points of earning of equilibrium temperature at different ambient temperatures are observed. Corresponding to the maximum earning of equilibrium temperature, the output power of the organic Rankine cycle ranges from 7.63 kW to 2.89 kW. These results show significant energy savings by applying the proposed system in the hydraulic system. |
Databáze: | OpenAIRE |
Externí odkaz: |