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Summary This article presents a large eddy simulation and experimental study of cedar façade behavior exposed to a 900 kW window spilled flame. The experiments used for validation were carried out in the Building Research of Institute of Japan in Tsukuba according to JIS A 1310 method. The compartment fire was modeled by using the modified eddy dissipation model with a diffusion mixing time scale for the near wall laminar region of combustion model, oneEqEddy model of turbulence model, pyrolysis chemistry mode of pyrolysis model, and finite volume discrete ordinates method of radiation model. The fire flame is treated as optically thin, and a fixed radiant fraction 0.35 is used to calculate the radiation source term. The pyrolysis model of cedar was modeled and optimized according to the results of fire propagation apparatus test. The influence of cedar parameters on time‐to‐pHRR (peak HRR), pHRR, and (total heat release rate) THR curves of facade fire were clarified by a series of simulation varying from thermal density, conductivity, heat capacity, and pyrolysis reaction parameters. It indicates the simulation results show a reasonable good quantitative agreement with experimental measurements. The activation energy of cedar pyrolysis shows a great influence on the time‐to‐pHRR, low pHRR, and THR of cedar facade. [ABSTRACT FROM AUTHOR]

Introduction: Patients with combined burns and trauma are often seen in the United States. The combination of trauma with burns increases mortality. In contrast, the characteristics and outcomes of these cases remain unknown in Japan. This study investigated the characteristics and outcomes of trauma associated with burns in Japan., Methods: This multicenter retrospective cohort study was conducted by utilizing data from the Japan Trauma Data Bank for the period between 2004 and 2017. We evaluated the characteristics of burn patients (n = 5783) divided into two groups: burns only (n = 5537) and combined burns and trauma (n = 246). Clinical characteristics, including patient background, severity of trauma, injury mechanism, total body surface area affected, injury location, treatments, and clinical outcomes, were examined., Results: Most patients in both the groups were injured by flames. The number proportion of patients with 40-89% of the total body surface area affected was 1069/5537 (19.3%) in the burn-only group and 23/246 (9.3%) in the combined burn and trauma group. The in-hospital mortality was 1006/5537 (18.2%) in the burn-only group and 17/246 (6.9%) in the combined burn and trauma group., Conclusions: We demonstrated the characteristics of Japanese patients with burns only compared with those with combined burns and trauma. Flames were the main cause of burns, and in-hospital mortality was lower in the combined burn and trauma group associated with a smaller burn area., Competing Interests: Declaration of Competing Interest The authors declare no conflicts of interest related to this study., (Copyright © 2024 Elsevier Ltd and International Society of Burns Injuries. All rights reserved.)

In this paper, an improved auto disturbance rejection controller (ADRC) is applied to permanent magnet synchronous motor (PMSM) speed control system. Specifically, the improved ADRC is proposed to solve the defect that the nonlinear function of traditional ADRC is not differentiable at the piecewise point. In addition, considering that there are numerous parameters to be optimized in ADRC, an improved moth‐flame optimization (MFO) is proposed to obtain ADRC parameters, and adaptive inertia weight coefficient and optimization mechanism based on the fusion of refraction operation and chaotic search are proposed to improve the convergence speed and optimization accuracy for MFO. Simulation and experimental results show that the improvement strategies proposed in this paper can increase the optimization performance for MFO algorithm effectively so that obtained more appropriative ADRC parameters. The improved ADRC can effectively improve the tracking control performance of PMSM speed control system. © 2021 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

A flame-retardant jute/PP composite with excellent flame retarding and mechanical properties was prepared by the surface powder spraying process. The flame-retardant layer used the green and pollution-free β-cyclodextrin as a char agent. To improve the char forming ability of β-cyclodextrin, ammonium polyphosphate (APP) and melamine (MEL) were also used as acid source and a blowing agent, respectively. The results indicated that the char forming ability of β-CD could be improved by the reaction between β-CD and APP. The composite with 20% flame retardants containing β-CD, APP and MEL (1:2:1) showed the better flame-retardant properties. The LOI value of the composite increased to 27.8%, which reached the second fire resistance according to Japan's JISD 1201-77 standard, and the self-extinguishing time reached to 37 s. Compared with pure jute/PP, the PHRR value and Av-EHC value of the composites were reduced by 50% and 21%, respectively. The carbon residual at 700 °C was increased by 10.9%. The tensile strength and bending strength were increased by 5% and 19%. These results revealed that the flame retardancy, thermal stabilities and mechanical properties of composites containing β-CD/APP/MEL system were significantly improved by the surface powder spraying method. [ABSTRACT FROM AUTHOR]

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In this paper, we report on our investigations into the behavior of successive fire spread between multiple houses in an urban area. More specifically, to acquire data necessary for the validation of our computational models, we conducted a fire spread experiment with nineteen 1/3-scale model houses aligned in a former quarry at Iwafune Mt. in Tochigi Prefecture, Japan. Most previous experiments used wood cribs or gas burners as fire sources to investigate the behavior of a fully-developed urban fire, but gave less attention to its formation due to successive occurrence of fire spread between houses. Successive fire spread between houses cannot be adequately simulated as discrete fuel elements in urban areas without replicating the exterior geometry, including openings allocated in each wall; however, this factor, which affects the intensity of heat transfer between houses, has not yet been considered in previous experiments except those that used disused houses. The experiment comprised two tests. In test 1, fire spread between model houses did not occur as was originally expected because of the short duration of the fully developed fire phase at the fire origin model house. The average mass loss rate in the fully developed fire phase was 1.33 kg/s with the maximum flame height of 7.8 m. In test 2, ceilings and roofs of model houses that were left unburnt in test 1 were reinforced so as to enhance their compartmentation, which in turn extends the duration of fire at each model house and the heating period of the adjacent model houses. As a result, fifteen out of eighteen model houses were burnt due to successive fire spread that lasted for about 50 min. The estimated maximum heat release rate of the group fire was about 100 MW with the maximum flame height of 11.0 m. The flame height after roof burn-through was modeled by introducing a conversion factor into one of the standard flame height model considering fresh air supply through openings due to the pressure difference between inside and outside of a model house. Although the quantitative agreement was not satisfactory, the overall change in flame height over time was adequately captured with the present model. [ABSTRACT FROM AUTHOR]

Abstract: The concentrations of traditional brominated flame retardants (BFRs) and organophosphate flame retardants (OPFRs) in new consumer products, including electronic equipment, curtains, wallpaper, and building materials, on the Japanese market in 2008 were investigated. Although some components of the electronic equipment contained bromine at concentrations on the order of percent by weight, as indicated by X-ray fluorescence analysis, the bromine content could not be fully accounted for by the BFRs analyzed in this study, which included polybrominated diphenylethers, decabromodiphenyl ethane, tetrabromobisphenol A, polybromophenols, and hexabromocyclododecanes. These results suggest the use of alternative BFRs such as newly developed formulations derived from tribromophenol, tetrabromobisphenol A, or both. Among the 11 OPFRs analyzed, triphenylphosphate was present at the highest concentrations in all the products investigated, which suggests the use of condensed-type OPFRs as alternative flame retardants, because they contain triphenylphosphate as an impurity. Tripropylphosphate was not detected in any samples; and trimethylphosphate, tributyl tris(2-butoxyethyl)phosphate, and tris(1,3-dichloro-2-propyl)phosphate were detected in only some components and at low concentrations. Note that all the consumer products evaluated in this study also contained traditional BFRs in amounts that were inadequate to impart flame retardancy, which implies the incorporation of recycled plastic materials containing BFRs that are of global concern. [Copyright &y& Elsevier]