甜瓜常温运输不同堆高层次的三维轴向振动强度差异

西州蜜17号甜瓜采用发泡网单个包装,置于瓦楞纸箱(4个/箱)内,共2 849箱11层堆高,用货车后挂载装,设置底层(2箱高)、中层(6箱高)和顶层(10箱高)三个堆高层次处理,使用振动记录仪监测载重33 t、时速57 km/h、54 h运输全程的X轴向(左右方向)、Y轴向(前后方向)和Z轴向(上下方向)振动的响应加速度,分析不同堆装高度三维轴向振动加速度的差异,为采后甜瓜适宜的运输条件提供理论依据。试验结果表明,甜瓜运输全程85.87%~92.33%的X轴向振动加速度为0.020~0.058 g,70.85%~91.63%的Y轴向振动加速度为0.033~0.083 g,67.33%~74.91%的Z轴向振动加速度为0.093~0.140 g。常温运输的甜瓜垂直方向振动强度最高,前后方向次之,左右方向最低。堆装高度的增加将提高三维轴向的振动强度,中层和顶层堆高存在水平方向对垂直方向的振动递增效应。中层堆高瓜箱内的温度与相对湿度较低;顶层堆高的相对湿度较大,底层堆高的温度偏高。

Difference of Vibration Acceleration on 3 Dimensional Axial of Different Stacking Height Layers of Melon during Normal Temperature Transport

The differences of melons transport vibration acceleration on 3-axial of different stacking height layers were analyzed according to the truck transportation vibration monitoring at normal temperature, in order to offer the test basis for the further study on the simulated transport. 2 849 packages (4 fruits per package) about 33 t mask melons of Xizhoumi No.17 variety were packaged in foam nets and corrugated paper cartons, and stacked height of 11 layers then transported with open trucks at 57 km/h velocity. Vibration acceleration of X-axial (lateral), Y-axial (longitudinal) and Z-axial (vertical) of cartons stacked at bottom(2 cartons height layer), middle(6 cartons height layer) and top (10 cartons height layer) on cargo were measured during 54 h transportation. The results showed that, 85.87%~92.33% X-axial vibration acceleration ranged from 0.020~0.058 g, 70.85%~91.63% Y-axial vibration acceleration ranged from 0.033~0.083 g, 67.33%~74.91% Z-axial vibration acceleration ranged from 0.093~0.140 g correspondingly in entire course. The highest level vibration generated in vertical cargo during truck transportation at normal temperature, secondly in lateral and last in longitudinal. Rising of cartons stacking height increased 3-axial vibration level correspondingly. Cartons stacked at middle and top showed obvious response increment of vertical vibration and horizontal vibration. Temperature and relative humidity inside of cartons stacking at middle were lower than cartons at top and bottom, corresponding to the higher humidity inside of top cartons and higher temperature inside of bottom cartons.