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In order to improve the understanding of the burning behavior for the in-situ burning of the spilled crude oil on water, the influence of the oil pool diameter and oil layer thickness of pool fire on open water were studied in relation to the flame height, boilover, and burning efficiency. A series of experiments were conducted in a specially designed experimental setup which could simulate the boundary conditions of the actual ISB operation on water. Three quartz tubes with different diameters and three initial oil layer thicknesses were set as the initial conditions in this study. The results showed that the burning process of oil pool fire on open water could be divided into four stages which are growth stage, quasi-steady stage, decay stage and extinguishing stage. The average flame height of quasi-steady stage increased with oil pool diameter but was little influenced by the initial oil layer thickness. Boilover phenomena were observed in the experiment processes when the oil pool diameter was 150 mm, which showed much later boilover onset time, longer boilover duration and higher average flame height than that for the same size oil paool fire in steel vessel with water sublayer. The burning efficiencies increased with the initial oil layer thicknesses for a given oil pool diameter, which could be explained as the thermal insulation of oil layer. All of the burning efficiencies on experimental dimensions are below 65%, owing to the significant cooling effect of the large amount of water surrounding the burning system.

The safety, performance and durability of the Li-ion battery module are limited by the operating temperature especially in the hot temperature regions, hence the thermal management system is essential for battery module. In this paper a novel phase change material (PCM) and fin structure was proposed for the thermal management system of LiFePO4 battery module to reduce the maximum temperature and improve the temperature uniformity in high-temperature environment (40 °C). Carefully designed experiments were performed for model validation. The effects of PCM species, fin thickness, fin spacing and PCM thickness on the cooling performance of battery module were investigated numerically. The results showed that PCM-fin structure thermal management system with optimized design exhibited good thermal performance, keeping the maximum temperature of the battery surface under 51 °C at relatively high discharge rate of 3C. Moreover, by investigating the thermal behavior of PCM during discharge process and cycle test, it has been found that PCM-fin structure has the advantage of improving natural convection and heat conduction within the PCM structure, and as a result enhances heat dissipation efficiency and reduces failure risk in passive thermal management systems using PCMs.

In order to improve the working performance of the lithium-ion battery pack in continuous operation under different ambient temperatures, a coupled composite phase change material and liquid cooling thermal management system is proposed. The simulation for this system under a cycle that a 3C rate discharging and then a 0.5C charging was conducted, as well as comparison tests concerning factors such as cell-to-cell spacing, cell-to-tube distance, channel number and coolant velocity. Simulation results showed that the coupled system with suitable design exhibited good thermal performance at an ambient temperature of 30 °C, which kept the maximum surface temperature and the temperature difference of the battery pack at 41.1 °C and 4 °C at the end of 3C discharge. Then, the latent heat of phase change material was also recovered by the liquid cooling during the 0.5C charge. Specially designed experiments have also been conducted to verify the effectiveness and practicability of the proposed coupled system. Based on this system, a liquid cooling strategy was proposed for controlling the velocity and inlet temperature of coolant by monitoring the temperature of the phase change material and environment. This further improved the thermal performance of the battery pack during cycling at different ambient temperatures and significantly reduced the unnecessary power consumption of liquid cooling during this process.

Spontaneous combustion risk of sulfurized rust is the main cause of fire and explosion accidents during crude oil storage and transportation. In order to analyze the effect of crude oil on the thermal behavior of sulfurized rust, thermos-gravimetric analysis (TG) and differential scanning calorimeter (DSC) were used to evaluate the thermal behavior of the sulfurized rust, crude oil and their mixture. A deconvolution method is employed to analyze the complex thermal behavior of the mixture. The results indicate that the oxidation of crude oil can be separated into low temperature oxidation (LTO) and high temperature oxidation (HTO). The thermal behavior of mixture is similar to that of crude oil. It can be found that sulfurized rust may inhibit the decarboxylation reaction of crude oil in LTO while the sulfurized rust and crude oil promote each other in the HTO. With the increases of the mass percentage of crude oil, the onset temperature of mixture decreases and the reaction heat increases. The promotion effect is the most significant when the ratio of sulfurized rust and crude oil is 1:1.