Bats colliding with spinning wind turbine blades result in bat mortality. Carcass surveys at individual wind turbines vary from daily to once a week and from large cleared plots to only the road and pad area. A physics-based model is proposed to guide carcass surveys, for designing curtailment studies to detect treatment fatalities and for improving fatality estimates by accounting for unsearched areas. The model considers the effects of carcass size, weight, and drag, and it accounts for the turbine rotor size and rotation rate to simulate the trajectory of a carcass after it is struck by a wind turbine blade. A carcass parameter is defined as the ratio of drag force to body weight, which accounts for the relative effect of bat biophysical and aerodynamic characteristics. By applying restrictions on carcass survey and turbine yaw data, a limited sample of bat fatalities was obtained, and the analysis revealed that bats fall downwind of wind turbines, indicating wind drift significantly influences carcass fall trajectories. The new ballistics model includes the effect of wind drift on fall trajectory of a carcass. The model was used to investigate the sensitivity of carcass fall trajectories to variability of the input parameters. The tests showed that larger values of the carcass parameter, that is, when drag dominates, such as for small carcasses, resulted in larger downwind drift, whereas large carcasses with smaller carcass parameter values resulted in larger distances within the rotor plane. The relationship of wind speed and RPM was found to influence the carcass downwind distance more compared to the within rotor plane distance. Using carcass survey data, turbine operation data, and wind speed records, for seven bats surveyed the day after colliding with a wind turbine, modelled back-trajectories were used to identify the likely strike location on the rotor. The model can be improved by validating the modelled trajectories with the recorded bat-blade strikes in thermal videos. It should be noted that the findings of the present study are based on the bat fatalities that met strict criteria leading to small sample size and hence requires further evaluation for testing the robustness of the model.

中文翻译：

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蝙蝠撞击风力涡轮机的三维弹道模型的开发和测试

蝙蝠与旋转的风力涡轮机叶片相撞导致蝙蝠死亡。个别风力涡轮机的尸体调查从每天到每周一次，从大型清理地块到仅道路和垫区。提出了一个基于物理的模型来指导屠体调查，设计减少研究以检测治疗死亡率，并通过考虑未搜索区域来改进死亡率估计。该模型考虑了骨架尺寸、重量和阻力的影响，并考虑了涡轮转子尺寸和转速，以模拟骨架被风力涡轮机叶片撞击后的轨迹。尸体参数被定义为阻力与体重的比率，它解释了蝙蝠生物物理和空气动力学特性的相对影响。通过对尸体调查和涡轮偏航数据应用限制，获得了有限的蝙蝠死亡样本，分析显示蝙蝠落在风力涡轮机的下风向，表明风漂移显着影响尸体坠落轨迹。新的弹道模型包括风漂移对尸体坠落轨迹的影响。该模型用于研究胴体下落轨迹对输入参数可变性的敏感性。测试表明，较大的胴体参数值，即当阻力占主导地位时，例如对于小型胴体，会导致更大的顺风漂移，而具有较小胴体参数值的大型胴体导致转子平面内的距离更大。发现与转子平面内距离相比，风速和 RPM 的关系对胎体顺风距离的影响更大。使用胴体调查数据，在与风力涡轮机相撞后的第二天调查了七只蝙蝠的涡轮机运行数据和风速记录，使用建模的反向轨迹来确定转子上可能的撞击位置。可以通过使用热视频中记录的蝙蝠叶片撞击来验证建模轨迹来改进模型。应该指出的是，本研究的结果基于符合导致样本量较小的严格标准的蝙蝠死亡率，因此需要进一步评估以测试模型的稳健性。可以通过使用热视频中记录的蝙蝠叶片撞击来验证建模轨迹来改进模型。应该指出的是，本研究的结果基于符合导致样本量较小的严格标准的蝙蝠死亡率，因此需要进一步评估以测试模型的稳健性。可以通过使用热视频中记录的蝙蝠叶片撞击来验证建模轨迹来改进模型。应该指出的是，本研究的结果基于符合导致样本量较小的严格标准的蝙蝠死亡率，因此需要进一步评估以测试模型的稳健性。