Reflected sunlight from the Walkie-Talkie building in 20 Fenchurch Street, London, was reported to have caused the melting of plastic components of a car parked at street level in late August of 2013. The incident was explained by the concave-shaped south façade of the building, which converges solar radiation into a hotspot. In this study, we test the sunlight concentation hypothesis with a lighting simulation. A geometry model with material properties was created, and different weather situations were modelled. The results are illustrated in irradiance maps indicating time, position and peak heat fluxes. The highest simulated flux on the day of the incident was 3320 Wm⁻² (10 to 15 fold increase compared to direct solar radiation). Additionally, the specific time and day for maximum heat fluxes between June and December were determined . For the worst scenario, which was avoided becuase the sky was partially cover with clouds that day and the hotspot did not fall on street level, the simulations showed that the peak heat flux would have reached well over 4000 Wm⁻².

据报道，2013年8月下旬，来自伦敦Fenchurch Street 20号对讲机大楼的反射阳光导致停放在街道上的一辆汽车的塑料部件融化。建筑物将太阳辐射会聚成一个热点。在这项研究中，我们通过照明模拟测试了日光集中度假设。创建了具有材料属性的几何模型，并对不同的天气情况进行了建模。结果显示在表示时间，位置和峰值热通量的辐照图中。事故发生日的最高模拟通量为3320 Wm ^-2（与直接太阳辐射相比增加了10到15倍）。另外，确定了六月和十二月之间最大热通量的具体时间和日期。对于最坏的情况，由于当天天空被部分云覆盖并且热点没有落在街道上，因此避免了这种情况，模拟显示峰值热通量将远远超过4000 Wm ^-2。