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The ability to calculate the changes to vent flows when a sprinkler activates can lead to improved predictions of fire environments outside of the room of origin in sprinklered occupancies, ultimately leading to an engineering design tool based on numerical simulations. Hence, for the current study, numerical calculations using NIST Fire Dynamics Simulator (FDS) are compared with real scale compartment experimental data for unsprinklered and sprinklered cases. Mass flow rate and temperature are typical parameters used to quantify the flow induced by a fire in a compartment. Hence, numerical results for doorway mass flow rate and temperature are compared with the experimental data for three fire sizes in order to validate the numerical model. Then, using current experimental data for sprinkler characteristics, numerical calculations for doorway mass flow rate and temperature are compared with the experimental data for the three fire sizes of the sprinklered case.

In this paper, the aging processes of colored paving asphalt conforming to GB/15180-94 standard were studied by rotate thin film oven (RTFO) test. The results show that the established two dynamics models can be use to describe the aging velocity of the two kinds of colored paving asphalt perfectly. After aging, asphaltene content increased, resins and aromatics content, as well as saturate content decreased. As a result, the original colloidal structure of colored paving asphalt is destroyed, which deteriorates performance of the colored paving asphalt. During aging, the Gastel index (Ic), which is sensitive to aging conditions, decreased with increase of aging temperature and extension of aging time. Therefore, the Gastel index can be used to evaluate the aging resistance of the colored paving asphalt.

Passivity breakdown and pitting behavior in the presence of aggressive Cl− on ultra‐high strength steel Aermet 100, commonly used for landing gear, has been studied, the data are explained in view of the point defect model (PDM). Cyclic potentiodynamic polarization (CPP), electrochemical impedance spectroscopy (EIS), and X‐ray photoelectron spectroscopy (XPS) were examined to observe corrosion progress and corrosion products in the salt spray tests at 4, 8, 12, 16, and 20 days intervals. The breakdown behavior was studied using CPP, whereas scanning electron microscopy (SEM) and digital confocal microscopy were used to explore the micromorphology and depth distribution of pits. The cumulative distribution basically satisfies a normal probabilistic distribution at the different concentrations of chloride and pH, which is consistent with PDM assuming a near‐normal distribution of potential breakdown sites regarding to the cation vacancy diffusivity.

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