Experiment and analysis of potato-soil separation based on impact recording technology

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.