| Plastic film mulching technology is beneficial to the growth of crops and plays a role in increasing production and income.It has been rapidly promoted in agricultural production since it was introduced to my country in the 1970 s.With the extensive use of plastic film,the residual film left in the farmland has caused terrible "white pollution",which not only destroys the soil structure,causes crop yield reduction,and even affects the healthy development of my country’s agriculture.At present,the mechanized recovery of residual film has been widely used.In the process of residual film recovery,the stripping operation is the key link and the difficulty of residual film recovery.Aiming at the problems of serious film wrapping and poor film removal effect in the stripping device of the residual film recovery machine,a "mechanical + airflow" combined stripping device is designed,which is mainly composed of a blade-type stripping roller and a guide shell.The stripping and film transporting work can be completed in sequence.The specific research carried out is as follows:(1)The field investigation work was carried out,and the shallow soil residual film and soil samples were collected.The residual film samples were weighed to study the distribution of residual film before sowing;In order to understand the working environment of residual film recovery,the moisture content of soil samples was measured;The basic material properties of the residual film were measured,and the suspension speed and friction coefficient of the residual film were statistically analyzed.(2)Aiming at the problems of serious film wrapping and poor film removal effect in the film removal device of the residual film recovery machine,a combined "mechanical + air flow" film removal device was designed.The structure,composition and working principle of the stripping device are analyzed.The important parameters of the device and the stripping conditions were determined through the analysis of the stripping mechanism and the force analysis.(3)Fluent software was used to simulate the flow field inside the device,and the important factors affecting the eddy current inside the device were obtained;the rotational speed of the blade-type stripper roller,the inclination angle of the stripper blade,and the diameter of the stripper drum were used as test factors,and the eddy current in the device was used as the test factors.The ratio of the area to the effective area is used as the evaluation index to design a three-factor and three-level orthogonal simulation experiment.Through optimization,the optimal parameter combination suitable for the stripping flow field is obtained:the rotation speed of the blade-type stripping roller is 1721 r/min,The inclination angle of the stripping blade is 15°,and the diameter of the stripping roller is 187 mm.Using Ansys/Workbench software,the modal analysis of the blade-type stripper roller was carried out,and its first six-order frequencies were obtained.The analysis results showed that the blade-type stripper roller did not resonate during the working process,and the structure design was reasonable.(4)The stripping device was trial-manufactured with the optimal combination of parameters,and the field performance test was carried out.The results showed that the stripping rate of the stripping device was98.04%,and there was no film wrapping during the operation.It can meet the needs of recycling of residual film before sowing. |
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