A numerical investigation is performed to illustrate the effects of internal sheltering and outlet shaping on the surface temperature and infrared radiation characteristics of rear airframe with an integrating infrared suppressor. The results show that the internal sheltering between the mixing duct and rear airframe skin can decrease the peak temperature on the rear airframe side-surface corresponding to the mixing duct trailing section, either by a full-covering shelter or semi-covering contoured plate. Both schemes can effectively reduce the infrared radiation intensity in 3-5 μm and 8-14 μm bands detected in the horizontal detection plane as well as from the top in the vertical detection plane. However, the presence of a full-covering shelter affects the rotor downwash flow suction into the rear airframe, making the 3-5 μm infrared radiation intensity a little higher than the baseline case, when viewed from the bottom in the vertical detection plane. The outlet shaping could effectively improve the temperature distribution on the rear airframe side-surface, although it shows a weak role on reducing the infrared radiation intensity in 3-5 μm and 8-14 μm bands. By using the slit outlet structure to cool the lower side-surface of the rear airframe, the peak temperature could be maintained close to the ambient temperature, within a 10 K relative increase.
JIANG Kunhong
,
ZHANG Jingzhou
,
SHAN Yong
,
ZHENG Zhen
,
YANG Zongyao
. Effects of sheltering and outlet shaping on surface temperature and infrared radiation characteristics of rear airframe with an integrating infrared suppressor[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2020
, 41(2)
: 123497
-123497
.
DOI: 10.7527/S1000-6893.2019.23497
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