With the rapid development of urbanization in China, the gap between urban and rural areas is decreasing. The traditional approach of constructing fire stations based on urban built-up areas is no longer suitable for the needs of modern fire rescue. Therefore, a comprehensive fire station location model is proposed based on fire risk assessment. This method divides the protected area units based on the urban road network. By evaluating different regions based on spatial position, land attributes, population density, floor area ratio, and fire incident indicators, the fire rescue risk levels and categorize regions into four risk levels are assessed. Corresponding response times were determined, and an objective model was developed to maximize the coverage area for fire response. The Baidu API was utilized to accurately calculate driving distances and times, and Gurobi optimization software was used to solve the model. Taking Shanghai as an example, the fire station location and layout from two perspectives—re-planning based on overall station placement and re-planning based on existing stations—were analyzed. The results suggest that constructing around 150 fire stations in Shanghai would effectively meet the fire rescue needs, which aligns with the actual situation in Shanghai and demonstrates the strong applicability of this model. This approach enables the meeting of new demand for fire station construction due to the significant increase in the coverage area while effectively utilizing firefighting resources.

To explore the mechanism and detailed gas flow in the ceiling vented compartment due to the unique ceiling vented ventilation condition, a numerical study on fire induced gas flow in a narrow compartment is carried out. Using the Fire Dynamic Simulator (FDS) program, the detailed fire induced gas flow in the ceiling vented compartment is studied. The simulation has been validated with real fire experiments in the exact same set-up, and the simulation results was proved to be in accordance with the experiments. It was found that the ceiling vent flow was strongly controlled by the fire plume. Regardless the boundary resistance, a distinct gas flow cycle is found in the ceiling vented compartment. Such kind of ceiling vent flow is principally different from the normal doorway flow. The fire plume and reverse gas inflow together establish a flow cycle inside the compartment.

With the advancement of Fuel Cell Vehicles (FCVs), detecting hydrogen leaks is critically important in facilities such as hydrogen refilling stations. Despite its significance, the dynamic response performance of hydrogen sensors in confined spaces, particularly under ceilings, has not been comprehensively assessed. This study utilizes a catalytic combustion hydrogen sensor to monitor hydrogen leaks in a confined area. It examines the effects of leak size and placement height on the distribution of hydrogen concentrations beneath the ceiling. Results indicate that hydrogen concentration rapidly decreases within a 0.5–1.0 m range below the ceiling and declines more gradually from 1.0 to 2.0 m. The study further explores the attenuation pattern of hydrogen concentration radially from the hydrogen jet under the ceiling. By normalizing the radius and concentration, it was determined that the distribution conforms to a Gaussian model, akin to that observed in open space jet flows. Utilizing this Gaussian assumption, the model is refined by incorporating an impact reflux term, thereby enhancing the accuracy of the predictive formula.

To improve our understanding of flaming, smoldering, or self-extinction in the burning of wood, it is necessary to quantify the conditions that lead to self-extinguished and self-sustained smoldering combustion. Experiments were performed in a cone calorimeter under an external irradiation of 10 to 25 kW/m² to analyze the temperature and mass loss of self-extinguished and self-sustained smoldering. The smoldering front depth was the significant parameter used to capture the smoldering characteristic, and it was defined as the axial thickness that reaches the smoldering characteristic temperature. The critical smoldering front depth of self-extinguished smoldering was lower than 10–15 mm for 30 mm thick wood at 15.5 kW/m² irradiation. This critical depth decreased with the increase in heat flux, from 26.5 ± 1.5 mm at 10 kW/m² to 11 ± 1 mm at 25 kW/m². A simple theoretical analysis is proposed to explain the smoldering thickness threshold of self-sustained smoldering propagation based on the local heat balance. The equation predicts that the critical depth decreases as the heat flux increases, from 23.9 mm at 8 kW/m² to 7.3 mm at 25 kW/m². The predicted critical depth and heating duration were consistent with the experimental results. This study proposes a feasible parameter to help understand the threshold of smoldering propagation and the development of biomass burners.

In this study, small-scale aviation kerosene pool fire experiments were carried out. The experiments were conducted by measuring the flame temperature and plume temperature on the axis by thermocouples and obtaining 50% of the flame intermittency height from the images taken by the camera. Using the Heskestad’s model, the fitting result of flame height and pan size was obtained. Moreover, the surface emission power of aviation kerosene flame was calculated based on the cylindrical flame theory. The experimental data in this paper will contribute to studies of aviation kerosene fire simulations.

The ultra-high-voltage (UHV) transmission engineering of China leads the world. However, the presence of large oil-filled equipment in converter stations poses explosion and fire risks. The safety operation is critical for its large-scale development. This study proposes a fire safety assessment strategy based on fire risk and the Internet of Things (IoT) according to the distribution characteristics of fire risks in converter stations. The fire safety assessment index system was established through theoretical analysis, on-site inspections, and case validation, including 5 primary indicators, 23 secondary indicators, and 67 tertiary indicators. The Analytic Hierarchy Process (AHP) and fuzzy comprehensive evaluation are employed to analyze and calculate the weights of each assessment indicator. The model was applied to typical converter stations. The results have guided the improvement of equipment safety and firefighting forces.