The physical properties of organic aircraft deicers under low temperature

Abstract

Ethylene glycol (EG) deicer and propylene glycol (PG) deicer were frequently used as the aircraft de-icing fluids in cold region. In this paper, the icing pressure (Ip), icing volume expansion rate (ΔVP), freezing point (T0) and under-cooling (△T) of aircraft deicers with different concentrations were investigated, and the above indicators of aircraft deicers were also compared with that of water and NaCl deicers. The results showed that the icing volume expansion of deicers was the direct cause of icing pressure. During the cooling process, values of Ip and ΔVP firstly increased sharply, then slowly, and finally became stable. The stabilized values of Ip and ΔVP decreased with concentration. The stabilized Ip value of EG deicer was slightly higher than that of 3.5% NaCl deicer and far greater than 3.5% PG deicer. Of all the tested deicers, the stabilized ΔVP value of NaCl deicer was the highest and that value of EG deicer was close to that of PG deicer. The results further confirmed the feasibility of using impulse of icing pressure as the indicator to evaluate the freeze-thaw deterioration to concrete.