The Heat and Mass Transfer Analysis of a Leaf  

作　　者：Hong Ye Zhi Yuan Shuanqin Zhang 

机构地区：[1]Department of Thermal Science andEnergy Engineering, University of Science and Technology of China, Hefei 230027, P. R. China [2]The First Engineers Scientific Research Institute, Wuxi 214035, P. R. China

出　　处：《Journal of Bionic Engineering》2013年第2期170-176,共7页仿生工程学报（英文版）

基　　金：Acknowledgment This work was funded by National Nature Science Foundation （No. 50402009）.

摘　　要：Understanding the heat and mass transfer processes of plant leaves is essential for plant bionic engineering. A general thermophysical model was established for a plant leaf with particular emphasis on the transpiration process. The model was verified by the field measured stomatal resistance and temperature of a camphor leaf. A dynamical simulation revealed that diurnal transpiration water consumption is dominated by the solar irradiance and the day-average temperature of the leaf is dominated by the ambient air temperature; transpiration plays an important role in the cooling of the leaf, in average it could dissipate around 32.9% of the total solar energy absorbed by the leaf in summer. To imitate the thermal infared characteristic of the real leaf, the up surface of the bionic leaf must have emissivity and solar absorptivity close to those of a real leaf and its shape and surface roughness must be similar to those of the real leaf. The key point is that the bionic leaf must be able to evaporate water to simulate the transpiration of a plant leaf, appropriate adsorbent can be used to realize this function.Understanding the heat and mass transfer processes of plant leaves is essential for plant bionic engineering. A general thermophysical model was established for a plant leaf with particular emphasis on the transpiration process. The model was verified by the field measured stomatal resistance and temperature of a camphor leaf. A dynamical simulation revealed that diurnal transpiration water consumption is dominated by the solar irradiance and the day-average temperature of the leaf is dominated by the ambient air temperature; transpiration plays an important role in the cooling of the leaf, in average it could dissipate around 32.9% of the total solar energy absorbed by the leaf in summer. To imitate the thermal infared characteristic of the real leaf, the up surface of the bionic leaf must have emissivity and solar absorptivity close to those of a real leaf and its shape and surface roughness must be similar to those of the real leaf. The key point is that the bionic leaf must be able to evaporate water to simulate the transpiration of a plant leaf, appropriate adsorbent can be used to realize this function.

关 键 词：heat and mass transfer leaf temperature transpiration water consumption thermal infrared 

分 类 号：S793.9[农业科学—林木遗传育种] TS205.1[农业科学—林学]