| The rice is an very important food in the world. Rice planting areas share 23 percent of the total corn areas , the total yield occupies 29 percent. The rice is also one of important foods in our country, according to the relevant data of information center of national food and oil organization: the area of rice-planting is about 2823 ten thousand hectare in the year of 2004,and the yield is about 1770 hundred million kg. The yield per hectare is 6300 kg(namely 420 kg/acre),far higher than the level for yield 193 kg of average acre of current world rice. Further increasing the rice yields per unit area and the total yields in our country is very important for the sustainable development of rice-producing and the security problem of grain in the world.An important method of increasing rice yield per unit area is to improve the rice-planting mechanization lever and use advanced planting technology. The rice-planting mechanization includes rice transplanting and direct-sowing. In order to advance the working productivity ground productivity economize cost economize water make the completely mechanical production of rice, the ideal technology is rice direct-sowing. And in direct-sowing, the technology of rice-bud direct-sowing spread out quickly, it has many advantages: Firstly, after the seed germination, it is increased the ability to resist the low temperature, reduced the process of absorbing water in the soil, seed's survival ratio is higher than non-seed, and the young plants can come out earlier; Secondly, passing through the germination process, we can seek out bad seeds, improve the seedling rate; Finally, it can shorten the grouth period of time ,reduce the progress of breeding and suspending, reduce the cost. Thus it can be seen that rice-bud direct-sowing is an ordinary planting mode, the investment is little and the performance is high, it's operation is convenient, alleviating labour intensity greatly. It is an important reformation to the traditional mode, and it's developmental foreground is wide.The precision seeding technology is difined that according to the agricultural request including regulated row-spacing column-spacing planting depth etc., crop seed can be sowed to the soil with single number. It is a kind of modinized technology to increase rice yield per unit area. Precision seed sowing device is core of precision seeding-machine, it's performancecriterion is sowing equality degree. According to the sowing principle, the Precision seed sowing device can be divided into mechanism drive and air drive. The precision seed sowing device by air is not stricted with seed dimension, the seed does not need select carefully; and in order to sow other seed , wo can replace sowing component quickly; and we can work with an upper velocity. According to above advantages, the precision seed sowing device by air is developmental aspect for high speed sowing device.Suction planter is a kind of advanced seed sowing device. With its special advantage, it is mainly used for sowing cultivation crop, then its using for sowing rice bud is little reported. This papers that aim at the working process of the suction planter proceeded a lot of trial research.Firstly, established the trial setting to examine the sunction planter performance. The trial setting mainly included PSJ sowing performance tester precision seed sowing device for rice-bud exhaust fan pressure register board, etc.Secondly, introduced the structure and the working principle of the sunction planter. According to the working principle, divide the seed device into filling seed area taking seed area and casting seed area, analyze the seed to suffer the dint circumstance in different districts, and put forward the bore absorb the seed term. The seed was absorbed by the bore and need vacuum size. According to analysis result, considering that affecting suction seed dependable factor is vacuum, disk rotate speed, suction area, and seed characteristic, etc.This papers used hydro-engineering simulation software FLUENT to simulate the process of filling seed and casting seed of the sunction planter, introduced how to use the software of FLUENT to set up the mold, mesh division, add to the boundary term, etc. in detail, and the value imitates the result contrasts with experiment data ,fitting together better. FLUENT can imitate availably the air room flow, pressure and the trajectory of seed, velocity field distributes etc. This will beneficial to analyze the sowing device performance, then providing foundation to optimize further design.In order to improve the casting seeds performance of the sunction planter, find out the factors of effecting sowing equality degree, we use the high-speed video to examine the casting seeds process. After observing the casting seeds through high speed CCD video, weobserved three kinds of gesture of the seeds to be attached, and attained the trajectory of them when they moved down; Then I proceeded the kinematics analyzes to casting seeds process, the result express casting seeds time deviation affect sowing equality degree, so the planter can not reach the request of precision sowing.Above research contents just the precision seeding-machine of rice bud sows principium result. The other function needs further research.
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