This paper introduced supersonic expansion liquefaction technology into the field of hydrogen liquefaction.The mathematical model for supersonic condensation of hydrogen gas in a Laval nozzle model was established.The...This paper introduced supersonic expansion liquefaction technology into the field of hydrogen liquefaction.The mathematical model for supersonic condensation of hydrogen gas in a Laval nozzle model was established.The supersonic expansion and condensation characteristics of hydrogen gas under different temperature conditions were investigated.The simulation results show that the droplet number rises rapidly from 0 at the nozzle throat as the inlet temperature increases,and the maximum droplet number generated is 1.339×10^(18)kg^(-1)at inlet temperature of 36.0 K.When hydrogen nucleation occurs,the droplet radius increases significantly and shows a positive correlation with the increase in the inlet temperature,and the maximum droplet radii are 6.667×10^(-8)m,1.043×10^(-7)m,and 1.099×10^(-7)m when the inlet temperature is 36.0 K,36.5 K,and 37.0 K,respectively.The maximum nucleation rate decreases with increasing inlet temperature,and the nucleation region of the Laval nozzle becomes wider.The liquefaction efficiency can be effectively improved by lowering the inlet temperature.This is because a lower inlet temperature provides more subcooling,which allows the hydrogen to reach the thermodynamic conditions required for large-scale condensation more quickly.展开更多
In order to further understand the effect of solid impurities on pipeline wall during erosion,the particle impact process without fluid was extracted for specific study.The effect of multi-impact particles on the wall...In order to further understand the effect of solid impurities on pipeline wall during erosion,the particle impact process without fluid was extracted for specific study.The effect of multi-impact particles on the wall of pipeline was studied experimentally and simulated.In this experiment,an improved ejection apparatus was implemented to carry out multi-impacts non-overlapping impingement by rhombic particles made of high speed steel(W18Cr4V)on the AA6061 aluminum alloy plate through changing particle angle,incident angle,orientation angle and impact velocity.As a result,each particle's penetration depth was investigated and particles' rebound trajectory can be described through this experiment as well as surface morphology of the target material after impingement.The ductile damage criterion,shear damage criterion and MSFLD damage criterion were jointly implemented in ABAQUS/CAE software to simulate the whole process of collision which proved to be effective by getting consistent result compared with experimental data.It is found that under the condition of continuous non-overlapping impact,the target material produces a small work hardening effect in the impact area by converting kinetic energy of moving particles into internal energy of plate so as to reduce the penetration depth of each impact particle.展开更多
The influence of the material stress state induced by internal and external forces on the erosion rate of pipelines has rarely been investigated in the literature.In order to fill this gap,using a tensile tester machi...The influence of the material stress state induced by internal and external forces on the erosion rate of pipelines has rarely been investigated in the literature.In order to fill this gap,using a tensile tester machine,a two–phase gas–solid particles jet erosion test was carried out considering a 316L stainless steel under different tensile stresses and different erosion angles.The results show that:1)In the elastic range,with the increase of stress,the erosion rate manifests a rising trend;2)In the metal plastic range,the increase of stress leads to a decrease of the erosion rate;3)The erosion rate at a small erosion angle is more sensitive to the increment of stress.The present research demonstrates that the combined effect of erosion and material internal stress can contribute to determine the effective resistance of the vulnerable parts of piping systems(such as elbows or similar components).展开更多
To improve the accuracy of erosion prediction,the effect of subsequent particles impacting the same area while the first single particle rebounds from the substrate must be considered.This issue has rarely been consid...To improve the accuracy of erosion prediction,the effect of subsequent particles impacting the same area while the first single particle rebounds from the substrate must be considered.This issue has rarely been considered in studies pertaining to erosion damage.In the present study,the ABAQUS software is used to investigate the erosion crater morphology and stress distribution on a target material subjected to overlapping impacts of spherical particles.Subsequently,the validated model is applied to investigate the effect of the overlapping impacts of particles on the target.Accordingly,the correlation between erosion severity and the impact locations of the two incident particles is quantified.The results show that the horizontal distance between two solid particle impact locations can significantly affect the erosion magnitude and pattern.The interactions of the resulting craters diminish when the horizontal distance exceeds 0.6 times the particle diameter.When the horizontal distance is approximately 0.06 times the particle diameter,the energy loss originating from collisions reaches the maximum,which modifies the crater morphology.The present study is expected to provide in-depth insights into erosion mechanisms and erosion modeling.展开更多
The internal erosion of pipelines in oil and gas storage and transportation engineering is highly risky.High gas velocity of annular flow entrained sand will cause damage to the pipelines,and may further result in thi...The internal erosion of pipelines in oil and gas storage and transportation engineering is highly risky.High gas velocity of annular flow entrained sand will cause damage to the pipelines,and may further result in thinning of the wall.If this damage lasts for a long time,it may cause pipeline leakage and cause huge economic losses and environmental problems.In this research,an experimental device for studying multiphase flow erosion is designed,including an erosion loop and an experimental elbow that can test the erosion rate.The annular flow state and pipe wall erosion morphology can also be tested by the device.The computational fluid dynamics(CFD)method is combined with the experiment to further study the annular flow erosion mechanism in the pipeline.The relationship between gas-liquid-solid distribution and erosion profile was studied.The results show that the most eroded region occurs be-tween 22.5° and 45° in the axial angle direction and between 90° and 135° in the circumferential angle direction of the elbow.The pits and deep scratches form on the surface of the sample after the sand collision.展开更多
Sand particle erosion is always a challenge in natural gas production.In particular,the erosion in gas-liquid-solid annular flow is more complicated.In this study,a three-phase flow numerical model that couples the vo...Sand particle erosion is always a challenge in natural gas production.In particular,the erosion in gas-liquid-solid annular flow is more complicated.In this study,a three-phase flow numerical model that couples the volume of fluid multiphase flow model and the discrete phase model was developed for prediction of erosion in annular flow.The ability of the numerical model to simulate the gas-liquid annular flow is validated through comparison with the experimental data.On the basis of the above numerical model,the phase distribution in the pipe was analyzed.The liquid entrainment behavior was reasonably simulated through the numerical model,which guaranteed the accuracy of predicting the particle erosion.Additionally,four erosion prediction models were used for the erosion calculation,among them,the Zhang et al.erosion model predicted the realistic results.Through the analysis of the particle trajectory and the particle impact behavior on the elbow,the cushion effect of the liquid film on the particles and the erosion morphology generation at the elbow were revealed.展开更多
基金supported by the National Natural Science Foundation of China(U2241257)the Postdoctoral Science Foundation of China(2022M723497)。
文摘This paper introduced supersonic expansion liquefaction technology into the field of hydrogen liquefaction.The mathematical model for supersonic condensation of hydrogen gas in a Laval nozzle model was established.The supersonic expansion and condensation characteristics of hydrogen gas under different temperature conditions were investigated.The simulation results show that the droplet number rises rapidly from 0 at the nozzle throat as the inlet temperature increases,and the maximum droplet number generated is 1.339×10^(18)kg^(-1)at inlet temperature of 36.0 K.When hydrogen nucleation occurs,the droplet radius increases significantly and shows a positive correlation with the increase in the inlet temperature,and the maximum droplet radii are 6.667×10^(-8)m,1.043×10^(-7)m,and 1.099×10^(-7)m when the inlet temperature is 36.0 K,36.5 K,and 37.0 K,respectively.The maximum nucleation rate decreases with increasing inlet temperature,and the nucleation region of the Laval nozzle becomes wider.The liquefaction efficiency can be effectively improved by lowering the inlet temperature.This is because a lower inlet temperature provides more subcooling,which allows the hydrogen to reach the thermodynamic conditions required for large-scale condensation more quickly.
基金financial support from the National Natural Science Foundation of China (China, Grant No. 51874340)the Natural Science Foundation of Shandong Province (China, Grant No. ZR2018MEE004)。
文摘In order to further understand the effect of solid impurities on pipeline wall during erosion,the particle impact process without fluid was extracted for specific study.The effect of multi-impact particles on the wall of pipeline was studied experimentally and simulated.In this experiment,an improved ejection apparatus was implemented to carry out multi-impacts non-overlapping impingement by rhombic particles made of high speed steel(W18Cr4V)on the AA6061 aluminum alloy plate through changing particle angle,incident angle,orientation angle and impact velocity.As a result,each particle's penetration depth was investigated and particles' rebound trajectory can be described through this experiment as well as surface morphology of the target material after impingement.The ductile damage criterion,shear damage criterion and MSFLD damage criterion were jointly implemented in ABAQUS/CAE software to simulate the whole process of collision which proved to be effective by getting consistent result compared with experimental data.It is found that under the condition of continuous non-overlapping impact,the target material produces a small work hardening effect in the impact area by converting kinetic energy of moving particles into internal energy of plate so as to reduce the penetration depth of each impact particle.
基金This paper is financially supported from the National Natural Science Foundation of China(Grant No.51874340)the Natural Science Foundation of Shandong Province(Grant No.ZR2018MEE004)Project of China Petroleum Engineering Construction Co.,Ltd.,China(Grant No.CPECC2020KJ07).
文摘The influence of the material stress state induced by internal and external forces on the erosion rate of pipelines has rarely been investigated in the literature.In order to fill this gap,using a tensile tester machine,a two–phase gas–solid particles jet erosion test was carried out considering a 316L stainless steel under different tensile stresses and different erosion angles.The results show that:1)In the elastic range,with the increase of stress,the erosion rate manifests a rising trend;2)In the metal plastic range,the increase of stress leads to a decrease of the erosion rate;3)The erosion rate at a small erosion angle is more sensitive to the increment of stress.The present research demonstrates that the combined effect of erosion and material internal stress can contribute to determine the effective resistance of the vulnerable parts of piping systems(such as elbows or similar components).
基金the National Natural Science Foundation of China(Grant No.51874340)the Natural Science Foundation of Shandong Province(Grant No.ZR2018MEE004)+1 种基金the National Key R&D Program of China(Grant No.2016YFC0802301)the Graduate Innovation Foundation of China University of Petroleum(East China)(Grant No.CXJJ-2022-44).
文摘To improve the accuracy of erosion prediction,the effect of subsequent particles impacting the same area while the first single particle rebounds from the substrate must be considered.This issue has rarely been considered in studies pertaining to erosion damage.In the present study,the ABAQUS software is used to investigate the erosion crater morphology and stress distribution on a target material subjected to overlapping impacts of spherical particles.Subsequently,the validated model is applied to investigate the effect of the overlapping impacts of particles on the target.Accordingly,the correlation between erosion severity and the impact locations of the two incident particles is quantified.The results show that the horizontal distance between two solid particle impact locations can significantly affect the erosion magnitude and pattern.The interactions of the resulting craters diminish when the horizontal distance exceeds 0.6 times the particle diameter.When the horizontal distance is approximately 0.06 times the particle diameter,the energy loss originating from collisions reaches the maximum,which modifies the crater morphology.The present study is expected to provide in-depth insights into erosion mechanisms and erosion modeling.
基金sponsored by Natural Science Foundation of Henan Province,China(No.212300410306)National Natural Science Foundation of China(No.51931008).
文摘The internal erosion of pipelines in oil and gas storage and transportation engineering is highly risky.High gas velocity of annular flow entrained sand will cause damage to the pipelines,and may further result in thinning of the wall.If this damage lasts for a long time,it may cause pipeline leakage and cause huge economic losses and environmental problems.In this research,an experimental device for studying multiphase flow erosion is designed,including an erosion loop and an experimental elbow that can test the erosion rate.The annular flow state and pipe wall erosion morphology can also be tested by the device.The computational fluid dynamics(CFD)method is combined with the experiment to further study the annular flow erosion mechanism in the pipeline.The relationship between gas-liquid-solid distribution and erosion profile was studied.The results show that the most eroded region occurs be-tween 22.5° and 45° in the axial angle direction and between 90° and 135° in the circumferential angle direction of the elbow.The pits and deep scratches form on the surface of the sample after the sand collision.
基金support of National Natural Science Foundation of China(No.51874340)Natural Science Foundation of Shandong Province(No.ZR2018MEE004)National Key R&D Program of China(No.2016YFC0802302).
文摘Sand particle erosion is always a challenge in natural gas production.In particular,the erosion in gas-liquid-solid annular flow is more complicated.In this study,a three-phase flow numerical model that couples the volume of fluid multiphase flow model and the discrete phase model was developed for prediction of erosion in annular flow.The ability of the numerical model to simulate the gas-liquid annular flow is validated through comparison with the experimental data.On the basis of the above numerical model,the phase distribution in the pipe was analyzed.The liquid entrainment behavior was reasonably simulated through the numerical model,which guaranteed the accuracy of predicting the particle erosion.Additionally,four erosion prediction models were used for the erosion calculation,among them,the Zhang et al.erosion model predicted the realistic results.Through the analysis of the particle trajectory and the particle impact behavior on the elbow,the cushion effect of the liquid film on the particles and the erosion morphology generation at the elbow were revealed.
