Improvement of Straw Throwing Performance of Harvester Based on Matching Header Width

Abstract

Aiming at the problem wherein a straw crushing and throwing device (SCTD) installed in a rice combine harvester (RCH) has a small throwing width and does not match the harvesting width, this paper proposes an improved plan for installing wind blades (WB) and optimizing the parameters of the deflector. The structural parameters of the WB were determined, and static analysis was carried out. The influence of the number of WB on the airflow field of the crushing chamber (CC) was studied by CFD simulation. The movement of the straw after entering the throwing device (TD) was analyzed. It was determined that the factors affecting the throwing width under the condition of a certain straw speed were the installation angle of the deflector (IAD), and the arc length of the deflector (ALD) through the bench test. The optimal combination of deflectors parameters was determined to match the width of the harvester header. When the straw feeding speed was 4 kg/s, and the straw moisture content was 33.80%, the optimal parameters are that the ALD was 400 mm and the IAD was 9°. The matching degree with the header width (4.50 m) is 98.44%. This study can effectively increase the straw throwing width and create conditions for the smooth implementation of straw returning to the field.