| As the key component of the pneumatic seeder,the performance of the pneumatic syst em plays a significant role in the seed-metering.At present,the momentum brought by the rear power outputting shaft is the main driver under the influence of terrible environment a nd surface features in the actual field experiment,however,it often triggers to rotational sp eed fluctuation,a problem often occurs in engine operation,which can cause some changes in the speed of wind turbines and led to the negative pressure of the seed-meter instability in further step,undermine the seed-metering performance eventually.The main research st udy is shown as the following:a.Optimizing design in pneumatic system transmission,the replacement of the hydrau lic transmission for the rear power outputting shaft as the solution for reducing the influenc e on the transmission made by the rotational speed of tractor engine in this article.Hydrauli c circuit is designed on request of the pneumatic seeder in operation,and then decide the h ydraulic components.Hydraulic circuit design is reasonable and it is proven by an experim ent based on the pneumatic corn planter 2BYQF-4 by the means of simulation on AMEsim software.The experiment indicates that the perfect negative pressure(4kPa~6kPa)can be achieved when the tractor rotational speed is lower in its operation by the adoption of this d evice.Compared to the traditional transmission mode,it promotes the effective workspace of engine rotational speed over 22.3%.The two problems,unstable long-time operation an d fixed working position,brought by the poor heating diffusion of the hydraulic system an d the three-point linkage working mode on the hydro-meter operation separately,are solve d.b.Upgrading the structure design of wind turbines and reducing its rotational speed in operation to make sure that the request on the negative pressure can be still satisfied under the low rotational speed in wind turbine operation.Taking hydrodynamics simulations on wind turbines through the Fluent date based simulation software,the width and the number of wind turbines and setting angel on outlets and inlets as experimental elements,negative pressure on inlets as assessment indicator,the three-factors and four-levels orthogonal expe riment is carried out.The best collaboration is drawn from the analysis on the variance data,with twelve turbines,fifty millimeters width and140°setting angle on the outlet.c.In accordance with the parameters from the best collaboration,3D model and simul ation are made through SolidWorks and Fluent software.A contrast with simulation results and experiment dates from original type wind turbines platform is also made.The result shows that updated wind turbines raise its rotational speed by 450 Pa on average at each level in operation and also satisfy the request on pneumatic seeder maintaining the rotational spe ed around 3400rpm~4600rpm in its operation(400rpm lower than the minimum rotational speed in operation),comparing with the original type wind turbines from the point of static pressure in inlets.Furthermore,it can be concluded that this solution can make an advance in the performance of wind turbine at low speed and a reduction on sensibility of its rotati onal speed fluctuation to enhance the pneumatic system stability of the pneumatic seeder. |
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