Effect of Shock Compression on Germination Rate of Plant Seeds
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摘要: 为分析冲击加载对植物种子萌发率的影响,利用轻气炮加载装置,对2种典型植物种子(苜蓿草种子和萝卜种子)进行飞片撞击实验。采用非显性有限元分析软件ANSYS AUTODYN,模拟盖板的变形以及冲击波在凹槽内的传播。通过测定实验后收集到的植物种子的萌发率,得到苜蓿草种子和萝卜种子的萌发率随峰值压力变化的关系。在385 MPa的峰值压力作用下,苜蓿草种子和萝卜种子的相对萌发率分别降为65.4%和6.1%。分析表明,实验中的种子破损是影响萌发率的次要原因。Abstract: The influence of shock compression on the germination rate of plant seeds was investigated experimentally by a light gas gun and numerically by finite element method.The deformation of cover-plate and the shock wave propagation in groove were simulated by ANSYS AUTODYN.The germination rates of two kinds of plant seeds (alfalfa and turnip) were assayed after experiments, and the experimental results indicated the different sensitivity of these two seeds and the relationship between germination rate and peak pressure.At the peak pressure of 385 MPa, the relative germination rates of alfalfa and turnip seeds were decreased to 65.4% and 6.1%, respectively.Different type of damage seeds were observed by a scanning electron microscope.It is believed that the damage is only a minor factor for germination rate of plant seeds.
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Key words:
- shock loading /
- plant seeds /
- germination rate /
- numerical simulation
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表 1 实验选用的植物种子参数
Table 1. Parameters of plant seeds in experiments
Seed Shape Size/(mm) Germination time/(d) Alfalfa Ovoid 12.64 3-5 Turnip Flat 17.80 7-12 表 2 不同撞击速度下的峰值压力
Table 2. Peak pressures under different impact velocities
No. v/(m/s) Peak pressure/(MPa) P1 93.5 116 P2 154.2 220 P3 165.2 237 P4 201.9 297 P5 229.8 385 表 3 冲击压缩后苜蓿草种子和萝卜种子的相对萌发率
Table 3. Relative germination rates of alfalfa and turnip seeds after shock compression
No. v/(m/s) Peak pressure/(MPa) aalfalfa/(%) aturnip/(%) P0 0 0 100.0 100.0 P1 93.5 116 81.6 46.5 P2 154.2 220 81.8 48.4 P3 165.2 237 75.4 33.8 P4 201.9 297 70.4 11.9 P5 229.8 385 65.4 6.1 -
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