囊式空气弹簧(convoluted air spring,CAS)的结构参数是影响其力学特性的重要因素,解决结构参数的辨识难题是计算囊式空气弹簧承载、刚度特性的关键途径。采用几何与力学分析方法,以单曲曲囊弧长和盖板有效法兰半径为关键设计参量,建立...囊式空气弹簧(convoluted air spring,CAS)的结构参数是影响其力学特性的重要因素,解决结构参数的辨识难题是计算囊式空气弹簧承载、刚度特性的关键途径。采用几何与力学分析方法,以单曲曲囊弧长和盖板有效法兰半径为关键设计参量,建立了基于关键设计参量的囊式空气弹簧统一结构参数预测模型。搭建了结构参数测试装置,试验验证了统一结构参数模型的正确性。揭示了CAS有效容积及其变化率、有效面积与关键设计参量均正相关,但有效面积变化率与曲囊弧长正相关、与有效法兰半径呈负线性相关特性,为设计刚度更低的CAS提供指导;进一步指出有效法兰半径对CAS结构参数的影响比曲囊弧长更为显著,增大有效法兰半径能够明显增大有效面积而显著提升CAS的承载特性,为保证工作气压不变前提下提升CAS承载能力提供了设计指引。研究结果为设计阶段准确计算囊式空气弹簧的结构参数、力学特性奠定基础,也为其结构参数设计与优化提供理论支撑。展开更多
In this paper,the performance analysis of recharging the borehole by means of exhaust-air energy is carried out.The results show that a vertical borehole used as heat source for a Ground Source Heat Pump(GSHP)can be r...In this paper,the performance analysis of recharging the borehole by means of exhaust-air energy is carried out.The results show that a vertical borehole used as heat source for a Ground Source Heat Pump(GSHP)can be recharged in high efficiency.With equal heat transfer capabilities of exhaust-air coil and borehole collector,the system provides a maximum overall efficiency.However,due to ground infinite capacity,the optimum brine flow rate is different from conventional two-exchanger system.The recharging system provides two peak overall efficiencies when the capacity ratio Cr=5 for laminar flow and Cr=15 for turbulent flow respectively.The overall efficiency is independent of exhaust-air temperature and undisturbed ground temperature,although the fluid properties depend on temperature.In practical system lower ethyl percentage brine should be chosen if the freezing point meets the system request,which can provide a higher overall efficiency.展开更多
文摘囊式空气弹簧(convoluted air spring,CAS)的结构参数是影响其力学特性的重要因素,解决结构参数的辨识难题是计算囊式空气弹簧承载、刚度特性的关键途径。采用几何与力学分析方法,以单曲曲囊弧长和盖板有效法兰半径为关键设计参量,建立了基于关键设计参量的囊式空气弹簧统一结构参数预测模型。搭建了结构参数测试装置,试验验证了统一结构参数模型的正确性。揭示了CAS有效容积及其变化率、有效面积与关键设计参量均正相关,但有效面积变化率与曲囊弧长正相关、与有效法兰半径呈负线性相关特性,为设计刚度更低的CAS提供指导;进一步指出有效法兰半径对CAS结构参数的影响比曲囊弧长更为显著,增大有效法兰半径能够明显增大有效面积而显著提升CAS的承载特性,为保证工作气压不变前提下提升CAS承载能力提供了设计指引。研究结果为设计阶段准确计算囊式空气弹簧的结构参数、力学特性奠定基础,也为其结构参数设计与优化提供理论支撑。
文摘In this paper,the performance analysis of recharging the borehole by means of exhaust-air energy is carried out.The results show that a vertical borehole used as heat source for a Ground Source Heat Pump(GSHP)can be recharged in high efficiency.With equal heat transfer capabilities of exhaust-air coil and borehole collector,the system provides a maximum overall efficiency.However,due to ground infinite capacity,the optimum brine flow rate is different from conventional two-exchanger system.The recharging system provides two peak overall efficiencies when the capacity ratio Cr=5 for laminar flow and Cr=15 for turbulent flow respectively.The overall efficiency is independent of exhaust-air temperature and undisturbed ground temperature,although the fluid properties depend on temperature.In practical system lower ethyl percentage brine should be chosen if the freezing point meets the system request,which can provide a higher overall efficiency.