摘要
No-till planting method is widely used for maize-wheat two-crops-a-year area in the North China Plain.However,cruel soil conditions,especially the large number of maize stalks which are hard to cutoff covering,often cause an unsatisfying planting quality.Based on the authors’previous investigation,ultrahigh-pressure(UHP)waterjet is capable to solve this problem and obtain qualified seedbeds.Thus,a UHP waterjet assisted furrow opener for no-till seeder was designed.Field tests showed that double-disc furrow openers worked well with UHP waterjet,since the sharpened disc blades could help to cut soil and residue,meanwhile,minimize soil disturbance.Response surface method(RSM)was used to investigate the relationship among forward speed,waterjet pressure,jet impingement angle and anti-blocking performance(stalks cutoff ratio and depth of soil cutting),and a Box-Behnken three-factor design was used to identify the optional operation parameters.A total of 17 combinations were conducted,and the results showed all three operation parameters significantly affected anti-blocking performance.Stalks cutoff ratio and depth of soil cutting increased with the increase of waterjet pressure,jet impingement angle,and decreased with the increase of forward speed.The optimization analysis indicated that when waterjet pressure was 267-280 MPa,jet impingement angle was 80.2°to 90.0°and forward speed was 4.00-4.42 km/h,the overall performance of UHP waterjet assisted double-disc furrow opener for no-till seeder was maximized.Stalks cutoff ratio could be above 95%and no blockage occurred.This study may provide a new approach and reference for the anti-blocking technology of no-tillage seeding.
基金
This study was financially supported by the Special Fund for Agro-scientific Research in the Public Interest from the Ministry of Agriculture,China(Grant No.201503136).