Doss Jereme R, Shanahan Michelle H, Wohl Christopher J, Connell John W
National Institute of Aerospace, Hampton, VA 23666-6147, United States.
Advanced Materials and Processing Branch, NASA Langley Research Center, Hampton, VA 23681-2199, United States.
Prog Org Coat. 2016 Jun;95:72-78. doi: 10.1016/j.porgcoat.2016.02.003. Epub 2016 Mar 11.
Coatings with the ability to minimize adhesion of insect residue and other debris are of great interest for future aircraft. These aircraft will exhibit increased fuel efficiency by maintaining natural laminar flow over greater wing chord distances. Successful coatings will mitigate the adhesion of debris on laminar flow surfaces that could cause a premature transition to turbulent flow. The use of surface modifying agents (SMA) that thermodynamically orient towards the air side of a coating can provide specific surface chemistry that may lead to a reduction of contaminate adhesion. Aluminum surfaces coated with urethane co-oligomers containing various amounts of pendant fluoroalky ether groups were prepared, characterized and tested for their abhesive properties. The coated surfaces were subjected to controlled impacts with wingless fruit flies () using both a benchtop wind tunnel and a larger-scaled wind tunnel test facility. Insect impacts were recorded and analyzed using high-speed digital photography and the remaining residues characterized using optical surface profilometry and compared to that of an aluminum control. It was determined that using fluorinated oligomers to chemically modify coating surfaces altered the adhesion properties relative to the adhesion of insect residues to the surface.
具有将昆虫残留物和其他碎片的附着力降至最低能力的涂层，对未来飞机具有极大的吸引力。这些飞机通过在更大的翼弦距离上保持自然层流，将展现出更高的燃油效率。成功的涂层将减轻碎片在层流表面的附着力，而这种附着力可能会导致过早地过渡到湍流。使用热力学上朝向涂层空气侧取向的表面改性剂（SMA），可以提供特定的表面化学性质，这可能会减少污染物的附着力。制备了涂覆有含有不同量侧链氟代烷基醚基团的聚氨酯共聚体的铝表面，对其进行了表征，并测试了它们的防粘性能。使用台式风洞和更大规模的风洞测试设施，对涂覆表面进行了无翅果蝇（）的受控撞击试验。使用高速数码摄影记录并分析昆虫撞击情况，使用光学表面轮廓仪对剩余残留物进行表征，并与铝对照物进行比较。结果表明，使用氟化共聚体对涂层表面进行化学改性，相对于昆虫残留物在表面的附着力而言，改变了附着力特性。
