摘要
CO_2的密相状态是指其压力高于临界值、温度小于临界值的状态。为了研究密相CO_2输送管道的裂纹扩展推动力变化规律,根据Maxey裂尖气体局部压力—裂纹扩展速度关系式、声速与裂纹扩展速度关联式、BWRS状态方程,建立并求解了密相CO_2输送管道裂纹扩展推动力计算模型。模拟了不同输送温度下,CO_2和N2混合物密相输送管道的裂纹扩展推动力变化规律。结果表明:在相同输送温度下,介质中的CO_2浓度越高,管道的裂纹扩展推动力越小;当介质中的CO_2浓度相同时,输送温度越高,管道的裂纹扩展推动力越高。在不发生相变的前提下,应尽量降低管道的输送温度,减少输送介质中的杂质含量,从而减小密相CO_2输送管道发生裂纹扩展的可能性。
The pure CO2 keeps in dense phase when the pressure is higher than the critical pressure and the temperature is lower than the critical temperature. The crack-driving force model for CO2 pipelines was established and solved based on Maxey＇s fracture tip pressure-fracture propagation velocity correlation,the sonic-fracture velocity correlation and the BWRS equation of state. The proposed model was applied to simulate the crack-driving force of dense phase CO2 transmission pipelines at different temperatures and with different N2 concentrations. At the same operation temperatures,the crack-driving force decreases with increasing CO2 content in mixtures. When the CO2 content keeps a constant,the crack-driving force increases with increasing temperatures. In order to reduce the crack-driving force and the probability of fracture propagation,impurities in CO2 mixtures should be removed,and the pipeline should be operated at low temperatures as long as no phase transition occurs.
出处
《机械强度》
CAS
CSCD
北大核心
2017年第6期1445-1449,共5页
Journal of Mechanical Strength
基金
国家自然科学基金项目(51604233
51504206)资助~~
关键词
CO2
管道
裂纹扩展
推动力
数学模型
CO2
Pipeline
Fracture propagation
Crack-driving force
Mathematical model
