Wathen P, Mitchell J W, Porter W P
Biophys J. 1971 Dec;11(12):1030-47. doi: 10.1016/S0006-3495(71)86276-8.
Convection properties of jackrabbit ears were examined in a wind tunnel and in the field in an attempt to study the possible thermal role of the large ears. This work was part of a study on energy exchange of appendages. Cylindrical copper models of various shapes, aluminum castings of domestic and jackrabbit ears, and an amputated jackrabbit ear were studied in a wind tunnel (a) to define the range for convective heat loss for appendages of various shapes, and (b) to study the effect on convection of model shape and orientation to the wind. Shape, i.e. length and closure, proved important. Orientation to the wind produced no consistent or significant variation in the convection coefficient. The convection coefficients from the ear castings fell within the range generated from the cylindrical models. The convection coefficients for the amputated rabbit ear fell partially within the range. Net thermal radiation loss at midday from the jackrabbit ears was found to be small. Convection from the ears, however, could account for the loss of over 100% of the animal's metabolic heat at an air temperature of 30 degrees C. If air temperature exceeds body temperature, the animal must either store heat or resort to the evaporation of water.
在风洞中和野外对长耳大野兔耳朵的对流特性进行了研究，以探究大耳朵可能具有的散热作用。这项工作是关于附属肢体能量交换研究的一部分。在风洞中研究了各种形状的圆柱形铜模型、家兔耳朵和长耳大野兔耳朵的铝铸件以及一只被截断的长耳大野兔耳朵，目的如下：(a) 确定各种形状附属肢体对流热损失的范围；(b) 研究模型形状和风向对对流的影响。结果表明，形状（即长度和闭合情况）很重要。风向对对流系数没有产生一致或显著的变化。耳朵铸件的对流系数落在圆柱形模型产生的范围内。被截断的兔耳的对流系数部分落在该范围内。发现长耳大野兔耳朵在中午的净热辐射损失很小。然而，在30摄氏度的气温下，耳朵的对流散热可能超过动物代谢产热的100%。如果气温超过体温，动物必须要么储存热量，要么依靠水分蒸发散热。
