In order to explore the aerodynamics characteristics of flax threshing material,and accurately obtain the movement trajectory of the material of each component in air-screen cleaning,the suspension velocities of flax ...In order to explore the aerodynamics characteristics of flax threshing material,and accurately obtain the movement trajectory of the material of each component in air-screen cleaning,the suspension velocities of flax grains,capsules,short stalks and capsule husks at different stages were measured by means of the suspension velocity device.The experimental results showed that the suspension velocity range was 4.55-8.64 m/s for flax grains,6.46-10.90 m/s for flax capsules,3.23-7.75 m/s for flax short stalks,and 1.06-4.21 m/s for flax capsule shells.Based on the experimental results,the overall interval distribution of each component of flax threshing material and the separation characteristics were discussed and the discrete element model of each component of the flax threshing material was established.Through simulation measurement of angle of repose of the material and the sliding friction angle with steel,the reliability of the established model was verified.The gas-solid coupling method was used to simulate the suspension velocity of each component of the flax threshing material,and the suspension velocity of the four components of flax threshing material was obtained.The simulation measurement results were within the actual measurement range,showing that the test results were basically in line with the simulation results.The simulation on the suspension velocity of different components of flax threshing material based on gas-solid coupling had high precision degree.Therefore,the feasibility of the suspension velocity of the flax threshing material measured in the simulation test based on CFD-DEM coupling was verified.展开更多
On the basis of analysing the outer performance degradation of shock absorber on suspenson and from the relationship between outer and inner performances of the shock absorber, an internal relationship between the str...On the basis of analysing the outer performance degradation of shock absorber on suspenson and from the relationship between outer and inner performances of the shock absorber, an internal relationship between the structure design and degradation of the shock absorber is discussed in the paper. From dynamic property, analysed the dynamic cause for degradation, the paper proposes a technical method of improving outer performance and a concept of critical velocity, and discusses what effects the critical velocity and the outer performance mance degradation has.展开更多
基金supported by China Agriculture Research System of MOF and MARA(Grant No.CARS-14-1-28)Fuxi Young Talents Fund of Gansu Agricultural University(Gaufx-03Y01)Key Research and Development Program of Gansu Province(20YF3WA019).
文摘In order to explore the aerodynamics characteristics of flax threshing material,and accurately obtain the movement trajectory of the material of each component in air-screen cleaning,the suspension velocities of flax grains,capsules,short stalks and capsule husks at different stages were measured by means of the suspension velocity device.The experimental results showed that the suspension velocity range was 4.55-8.64 m/s for flax grains,6.46-10.90 m/s for flax capsules,3.23-7.75 m/s for flax short stalks,and 1.06-4.21 m/s for flax capsule shells.Based on the experimental results,the overall interval distribution of each component of flax threshing material and the separation characteristics were discussed and the discrete element model of each component of the flax threshing material was established.Through simulation measurement of angle of repose of the material and the sliding friction angle with steel,the reliability of the established model was verified.The gas-solid coupling method was used to simulate the suspension velocity of each component of the flax threshing material,and the suspension velocity of the four components of flax threshing material was obtained.The simulation measurement results were within the actual measurement range,showing that the test results were basically in line with the simulation results.The simulation on the suspension velocity of different components of flax threshing material based on gas-solid coupling had high precision degree.Therefore,the feasibility of the suspension velocity of the flax threshing material measured in the simulation test based on CFD-DEM coupling was verified.
文摘On the basis of analysing the outer performance degradation of shock absorber on suspenson and from the relationship between outer and inner performances of the shock absorber, an internal relationship between the structure design and degradation of the shock absorber is discussed in the paper. From dynamic property, analysed the dynamic cause for degradation, the paper proposes a technical method of improving outer performance and a concept of critical velocity, and discusses what effects the critical velocity and the outer performance mance degradation has.