Research And Simulated Analysis For Corn Stalk Harvesting Technology And Equipment

Corn stalks are important biomass resources. Compared with fossil fuels, biomass has characteristics of being renewable, low pollution and zero emissions of carbon dioxide. Compared with other renewable energy resources, it has characteristics of being abundant, widely distributed, and multi-purpose. With the continuous development of modern biomass technologies, biomass will play an important role in the sustainable energy systems in future. Many countries of the world are seeking to develop biomass for fuel. The UN Food and Agriculture Organization (FAO) predicted that by2050, biomass-based renewable energy will provide60percent of the world’s electricity and40percent of the fuel.There are two issues that constrain corn stalk collection and utilization in China. Firstly, the water content of corn stalks is70%～80%during the harvest season. If left to dry naturally, the water loss rate will be very slow. This will have an adverse effect on the harvesting and baling. Secondly, corn stalks are hard and strong and difficult to bale due to the elastic recovery. The bale is easy to produce but tends to expand after compaction. Supported by National863Project and National Science and Technology Support Plan, this research was carried out by focusing on the above issues. The research aim was to develop a corn stalk adjusting(squeezing and kneading stalks,let it to be broken and split the epidermis) technology,and manufacture corn harvester with stalks adjusting device.Key technologies of corn stalks harvesting include cutting technology and adjusting technology. The theory and typical mechanism of these two technologies was researched, and experiments for cutting and adjusting corn stalk were carried out. A corn stalks cutting and adjusting parts were developed for the first time in China, they can quickly break the nodes and split the epidermis.3D solid modeling technology, the multi-body dynamics simulation technology and flexible body modeling technology were adopted during research on corn stalk cutting and adjusting parts. A corn stalk flexible body model was developed for the first time. A simulation experiment for stalk bending and adjusting was carried out. Digital prototyping for corn stalk cutting and adjusting device was built based on the flexible body model. Virtual simulation for cutting, conveying, adjusting corn stalk was realized. Kinematics and dynamics analysis was carried out and parameters of corn stalk and related working parts was achieved. The effectiveness of the simulation platform was tested.A prototype of corn harvester with stalk adjusting device was manufactured,which was integrated a row independent corn snapping head,a corn stalk cutting and adjusting device, a removing stems and leaves device, a ear transport and storage device, full hydraulic power self-propelled chassis. The matching application of corn harvesting technology and stalk adjusting technology was realized for the first time. Simultaneously with the harvesting of ears, the corn stalks can be cut, conveyed, squeezed and broken, and the epidermis split, stalks mechanics and physical state thus can be changed, the water loss rate would be accelerated, the elastic recovery can be decreased, the stalk can be baled with high density. This will promote the large scale utilization of corn stalks as a biomass fuel. The new R&D model of agricultural machine was explored, and technical support to accelerate the development cycle and reduce development cost was provided. Through independent innovation development, core technologies and equipment suited to China’s national conditions were acquired, The establishment of corn stalk collecting, curing, molding technology system was promoted.