Harvesting and storing energy is a key problem in some applications.Elastic energy storage technology has the advantages of wide-sources,simple structural principle,renewability,high effectiveness and environmental-fr...Harvesting and storing energy is a key problem in some applications.Elastic energy storage technology has the advantages of wide-sources,simple structural principle,renewability,high effectiveness and environmental-friendliness.This paper elaborates the operational principles and technical properties and summarizes the appli-cability of elastic energy storage technology with spiral springs.Elastic energy storage using spiral spring can realize the balance between energy supply and demand in some applications.Continuous input-spontaneous out-put working style can provide simple energy sources for short-time energy supply,and provide strong moment impact and rapid start,or realize the energy conservation for reciprocating movement.Uniform output working style can realize energy output with uniform speed for timekeeping and load-driving.Random input working style can harvest and store random mechanical energy or convert small torque into a large moment to drive external loads.Finally,this paper proposes new researches and developments of elastic energy storage technology on new materials and structures,mechanical properties and structural dynamics analyses,design and control for new functions.展开更多
Dynamic mechanical behaviour of resorcinol-formaldehyde matrix and its composites reinforced with natural fibers of Luffa cylindrica (LC) has been studied. The effects of fiber loading, alkali treatment on fiber, temp...Dynamic mechanical behaviour of resorcinol-formaldehyde matrix and its composites reinforced with natural fibers of Luffa cylindrica (LC) has been studied. The effects of fiber loading, alkali treatment on fiber, temperature and frequency on storage modulus and mechanical-loss factor of the composites were studied. The dynamic mechanical behaviour of the composites and pure matrix has been investigated in the frequency range from 0.1 Hz to 10 Hz and temperature range from 26℃ to 100℃. The experimental results show that the values of storage modulus of the composites increase with increase in fiber loading. The storage modulus of treated LC fiber composites were found to be enhanced when compared with the untreated fiber composites. It was also found that mechanical-loss factor was more when untreated LC fibers were incorporated in the composites and decreased with the incorporation of treated LC fiber. The storage modulus of all the composites increased with frequency but decreased with rise of temperature. The glass transition temperature of the composites was evaluated from the peaks of tan delta variations.展开更多
To systematically assess the rockburst proneness considering specimen shape,multiple groups of laboratory tests were performed on 5 rock materials in cylindrical and cuboid shapes.The linear energy storage(LES)law of ...To systematically assess the rockburst proneness considering specimen shape,multiple groups of laboratory tests were performed on 5 rock materials in cylindrical and cuboid shapes.The linear energy storage(LES)law of both cylindrical and cuboid rock specimens under uniaxial compressive load was confirmed,and the energy storage coefficient was found to be unrelated to specimen shape.On the basis of LES law,two rockburst proneness indexes,namely the strain energy storage index(W_(et))and the potential energy of elastic strain(PES),were modified.Subsequently,the W_(et),PES,peak-strength strain energy storage index(W_(et))p,and peak-strength potential energy of elastic strain(PESp)were used to assess the rockburst proneness of the cylindrical and cuboid specimens.In addition,the fragment ejection course of specimens under test was recorded by a high-speed camera.Then,the rockburst proneness judgments obtained from the 4 indexes were compared with the qualitative data during rock destruction.The results show that,under similar stress conditions,specimen shape has an ignorable effect on the rockburst proneness as a whole.The judgment accuracy of the two modified indexes,especially that of the PESp,is favorably improved to evaluate the rockburst proneness of both cylindrical and cuboid specimens.However,misjudgment ofW_(et)^(p)and PESp may still occur in the assessment of rockburst proneness as these two indexes only consider the energy state before rock peak strength and the W_(et)^(p)is formulated in a ratio form.展开更多
基金Thanks to Sichuan Province Innovation Team Project for Building Environment and Energy Efficient Utilization(No:2015TD0015)Major Project Engagement Fund of Southwest Jiaotong University,and Funda-mental Research Funds for the Central Universities(2682014CX014EM)for their financial aids.
文摘Harvesting and storing energy is a key problem in some applications.Elastic energy storage technology has the advantages of wide-sources,simple structural principle,renewability,high effectiveness and environmental-friendliness.This paper elaborates the operational principles and technical properties and summarizes the appli-cability of elastic energy storage technology with spiral springs.Elastic energy storage using spiral spring can realize the balance between energy supply and demand in some applications.Continuous input-spontaneous out-put working style can provide simple energy sources for short-time energy supply,and provide strong moment impact and rapid start,or realize the energy conservation for reciprocating movement.Uniform output working style can realize energy output with uniform speed for timekeeping and load-driving.Random input working style can harvest and store random mechanical energy or convert small torque into a large moment to drive external loads.Finally,this paper proposes new researches and developments of elastic energy storage technology on new materials and structures,mechanical properties and structural dynamics analyses,design and control for new functions.
文摘Dynamic mechanical behaviour of resorcinol-formaldehyde matrix and its composites reinforced with natural fibers of Luffa cylindrica (LC) has been studied. The effects of fiber loading, alkali treatment on fiber, temperature and frequency on storage modulus and mechanical-loss factor of the composites were studied. The dynamic mechanical behaviour of the composites and pure matrix has been investigated in the frequency range from 0.1 Hz to 10 Hz and temperature range from 26℃ to 100℃. The experimental results show that the values of storage modulus of the composites increase with increase in fiber loading. The storage modulus of treated LC fiber composites were found to be enhanced when compared with the untreated fiber composites. It was also found that mechanical-loss factor was more when untreated LC fibers were incorporated in the composites and decreased with the incorporation of treated LC fiber. The storage modulus of all the composites increased with frequency but decreased with rise of temperature. The glass transition temperature of the composites was evaluated from the peaks of tan delta variations.
基金National Natural Science Foundation of China,Grant/Award Number:41877272Fundamental Research Funds for the Central Universities,Grant/Award Number:2242022k30054。
文摘To systematically assess the rockburst proneness considering specimen shape,multiple groups of laboratory tests were performed on 5 rock materials in cylindrical and cuboid shapes.The linear energy storage(LES)law of both cylindrical and cuboid rock specimens under uniaxial compressive load was confirmed,and the energy storage coefficient was found to be unrelated to specimen shape.On the basis of LES law,two rockburst proneness indexes,namely the strain energy storage index(W_(et))and the potential energy of elastic strain(PES),were modified.Subsequently,the W_(et),PES,peak-strength strain energy storage index(W_(et))p,and peak-strength potential energy of elastic strain(PESp)were used to assess the rockburst proneness of the cylindrical and cuboid specimens.In addition,the fragment ejection course of specimens under test was recorded by a high-speed camera.Then,the rockburst proneness judgments obtained from the 4 indexes were compared with the qualitative data during rock destruction.The results show that,under similar stress conditions,specimen shape has an ignorable effect on the rockburst proneness as a whole.The judgment accuracy of the two modified indexes,especially that of the PESp,is favorably improved to evaluate the rockburst proneness of both cylindrical and cuboid specimens.However,misjudgment ofW_(et)^(p)and PESp may still occur in the assessment of rockburst proneness as these two indexes only consider the energy state before rock peak strength and the W_(et)^(p)is formulated in a ratio form.
