In order to understand the Supercooled Large Droplet (SLD) cloud evolution characteristics in icing wind tunnels, a method based on Eulerian theory is developed to simulate SLD cloud flows coupling of momentum, mass and heat transfer. Using this method, the evolution of SLD cloud is investigated for the horizonal contraction configuration of the main section in a 3 m×2 m icing wind tunnel. The SLD cloud evolution characteristics, including cloud sinking and contraction, cloud momentum equilibrium and cloud thermal equilibrium, are analyzed. The effects of droplet deformation and breakup on the SLD mechanical equilibrium characteristic are explored. The states of cloud momentum equilibrium and thermal equilibrium in the main test section are evaluated. Results show that SLD droplets with diameter larger than 250 μm would experience significant deformation in the configuration. The increased droplet size could enhance the degree of deformation. Particularly at the test section velocity of 160 m/s, SLD droplets with the diameter larger than 750 μm would break up. Then the effects of droplet deformation and breakup could increase the rates of droplet acceleration and temperature reduction, so that the SLD droplets would approach the momentum and thermal equilibrium states. The SLD cloud with the maximum diameter of 1000 μm shows size and concentration stratification, momentum stratification and thermal stratification at the configuration outlet. In the SLD cloud, the small droplets with diameter smaller than 100 μm would reach the equilibrium states with higher speed, lower temperature and constant condensation. However, large SLD droplets with diameter larger than 500 μm would deviate from equilibrium states significantly with lower speed, higher temperature and constant evaporation. Increased test section velocity could reduce the degree of SLD cloud concentration stratification, but enhance the degree of momentum and thermal stratification. In particular, in the condition with the test section of 160 m/s, the SLD cloud will be uniform in the central area of the outlet (almost -0.75 m < Y < 0.75 m and -0.5 m < Z < 0.5 m), but the maximum velocity difference and temperature difference compared with the equilibrium states are higher than 18 m/s and 20 ℃, respectively.
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