In order to discover the damage mechanism and improve separation performance in the separation process of potato-soil mixture,the experiment was conducted on an in-house test-bed.The impact recording device and high-s...In order to discover the damage mechanism and improve separation performance in the separation process of potato-soil mixture,the experiment was conducted on an in-house test-bed.The impact recording device and high-speed camera technology were employed in order to obtain the instantaneous dynamics of the potato-soil mixture for detail data analysis.Five vibration intensities were defined according to the vibration frequency and amplitude.It was found that the mean number of impacts and maximum impact acceleration increased significantly as the level of vibration intensity rose.As a result,the separation performance increased significantly,however,the bruising rate also increased to a certain extent.The mathematical relationship between the maximum impact acceleration and the factors of interest,including vibration amplitude,the vibration frequency and the operating speed of the separation sieves was established through the response surface experiment.It was demonstrated that the presented model was capable to reflect the degree of the factors on influencing bruising rate and separation performance.According to the significance on the maximum impact acceleration,the factors of interest were given in a descending order with vibration frequency,vibration amplitude,running speed of the separation sieve.A set of the optimum operating parameters were found to achieve a desired separation performance as follows,the vibration amplitude was 34.1 mm,the vibration frequency was 5.24 Hz,the running speed of the separation sieve was 2.05 m/s;where the maximum impact acceleration was 98.62 g,the relative error was 3.23%,the bruising rate was 1.81%and the separation performance was 98.5%.The presented model can potentially provide a technical reference for further investigation of the separation mechanism and development of measures for reducing the loss of separation.展开更多
Slungshots can be induced by earthquake, causing heavy damage to people. Preliminary study of this problem was carried out. Firstly,?a mathematical model for describing the movement of slungshot was presented based on...Slungshots can be induced by earthquake, causing heavy damage to people. Preliminary study of this problem was carried out. Firstly,?a mathematical model for describing the movement of slungshot was presented based on the theories of rigid body kinematics and aerodynamics. The effects of air drag and the rotation of rock were considered. Secondly, the trail of movement and the velocity were studied based on the presented model, taking the slungshot recorded in the 5.12 earthquake in the Yingxiu County as example. Thirdly, the impact force of the slungshot on the ground was studied. This study provides a reference for the forecast and prevention of the slungshot hazard.展开更多
基金supported by the Program for National Key Research and Development Plan(2016YFD0701603-02)Shandong Taishan Industry Leading Talent Project(LJNY201615)+2 种基金Shandong Province Major Science and Technology Innovation Project(2017CXGC0219)Innovative Research Team in University of China(IRT13039)Shandong Province Agricultural Machinery Equipment Research and Development and Innovation Project(2016YF034).
文摘In order to discover the damage mechanism and improve separation performance in the separation process of potato-soil mixture,the experiment was conducted on an in-house test-bed.The impact recording device and high-speed camera technology were employed in order to obtain the instantaneous dynamics of the potato-soil mixture for detail data analysis.Five vibration intensities were defined according to the vibration frequency and amplitude.It was found that the mean number of impacts and maximum impact acceleration increased significantly as the level of vibration intensity rose.As a result,the separation performance increased significantly,however,the bruising rate also increased to a certain extent.The mathematical relationship between the maximum impact acceleration and the factors of interest,including vibration amplitude,the vibration frequency and the operating speed of the separation sieves was established through the response surface experiment.It was demonstrated that the presented model was capable to reflect the degree of the factors on influencing bruising rate and separation performance.According to the significance on the maximum impact acceleration,the factors of interest were given in a descending order with vibration frequency,vibration amplitude,running speed of the separation sieve.A set of the optimum operating parameters were found to achieve a desired separation performance as follows,the vibration amplitude was 34.1 mm,the vibration frequency was 5.24 Hz,the running speed of the separation sieve was 2.05 m/s;where the maximum impact acceleration was 98.62 g,the relative error was 3.23%,the bruising rate was 1.81%and the separation performance was 98.5%.The presented model can potentially provide a technical reference for further investigation of the separation mechanism and development of measures for reducing the loss of separation.
文摘Slungshots can be induced by earthquake, causing heavy damage to people. Preliminary study of this problem was carried out. Firstly,?a mathematical model for describing the movement of slungshot was presented based on the theories of rigid body kinematics and aerodynamics. The effects of air drag and the rotation of rock were considered. Secondly, the trail of movement and the velocity were studied based on the presented model, taking the slungshot recorded in the 5.12 earthquake in the Yingxiu County as example. Thirdly, the impact force of the slungshot on the ground was studied. This study provides a reference for the forecast and prevention of the slungshot hazard.
