Design and Analysis of Automatic Fire Extinguisher for Vehicles

These days there is a rapid increase in automobile utilization in urban and rural areas, along with this there is an increase in the number of accidents related to automobiles. Apart from user/ driver related accidents a large number of other reasons cause fires in automobiles. Three components are needed to make a fire, Oxygen, Fuel and a source of ignition. Car fires are usually caused due to issues associated with fuel, electrical systems, the exhaust system and petroleum based fluids. By far though, the biggest causes of vehicle fires are fuel (gasoline) related. The source of fire can be external or within the vehicle itself. Vehicle fires used to be quite common. Back in 1980’s there were 456,000 car fires. In 1978 a big issue occurred with Pintos catching on fire. This led the manufacturers to look at what design changes in vehicles will limit the three elements of the fire triangle from coming together. Our project aims to design a device which automatically detect fire in vehicles and suppress them to prevent further damage to the vehicle. The device which contains sensors and an extinguisher and a microprocessor can be placed under the hood of vehicles near the engine compartment and works when the engine (or any other part) catches fire. This application minimizes the possibility of death or injury and loss of property due to fire accidents in vehicles.

Stochastic Thermal Demand and Resulting Capacity Loss of Concrete Tunnel Liners Subjected to Vehicle Fires

Fire resistant design of both structural and non-structural components in road tunnels is predicated on the determination of fire demand intensity. Current practice typically uses a conservative, deterministic fire curve that does not necessarily provide a representative evaluation of the spatial and temporal distribution of thermal demands in tunnels that are caused by large vehicle fires. This paper proposes a tunnel-specific probabilistic framework for evaluating vehicle fire frequency and intensity based on tunnel geometry and traffic information. The framework leverages a fast-running computational tool that has been previously developed by the authors for calculating fire-induced heat flux exposure on tunnel liners because of enclosed vehicle fires. The likelihood of a vehicular fire and the associated fire size distribution are used to generate probabilistic distributions of total fire exposure for the reinforced concrete tunnel liner. Critical heat flux values according to these probabilistic distributions are then used to assess reductions in concrete material strength and resulting losses in the structural performance of the system. A case study of the Fort Pitt Tunnel in Pittsburgh, PA, is included for demonstration. The proposed framework enables decision making regarding design and renovation of tunnels for fire resistance as well as post-fire inspection by quantifying the risk of capacity reduction in the concrete liner because of a realistic range of fire hazard intensities.

Epidemiology of Vehicle Fire Fatalities of Road Traffic Injuries in Kerman Province, Iran: A Cross-Sectional Study

BACKGROUND: Vehicle fires are one of the most important causes of fatalities in road traffic injuries (RTIs), but there are no accurate statistics about vehicle fire fatalities (VFFs) due to RTIs in Iran. AIM: This study aimed to investigate the Epidemiology of vehicle fire fatalities (VFFs) due to road traffic injuries (RTIs) in Iran.METHODS: In this cross-sectional study, a researcher-made checklist was used to collect the required data from the files of RTI fatalities in the Kerman Legal Medicine Organization (KLMO), or coroner’s office. All reported victims of vehicle fires in the ten years from 2007 to 2017 were included in the study. The data were analysed using SPSS ver. 18, with p = 0.05 considered as the level of significance. RESULTS: The authors found 124 cases of vehicle fire fatalities in Kerman, with a mean age of 30.45 ± 12.41, of which 50% were in the 25-49 years age group. Most frequently, the victims were Iranian (91.9%), married (66.1%), self-employed (51.6%), and urban dwellers (79.8%), and had died because of burns (91.9%). In 46.8% of cases, the victims were the driver, and in the remaining 53.2%, they were the passenger of the crashed vehicle. Most frequently, vehicle fires occurred on extra-urban roads (90.3%), during spring (35.5 %) or summer (32.3%), due to a vehicle-to-vehicle collision (66.9%), between sedans (69.9%), and at night (63.7%). Most victims died at the scene of the incident (87.9%) and had been transferred to hospital by an ambulance (71%).CONCLUSION: This study indicated that car fires caused the death of young and middle-aged people. The authors suggest the implementation of preventative measures promoting car safety; establishing speed management; establishing laws governing driving, manufacturing and importation of vehicles; construction of safe roads; identifying accident-prone points; installing road warning signs; establishing more roadside stations; ensuring stricter police monitoring; and improving vehicle safety standards and public awareness about the risks of speeding.

MICROSTRUCTURAL PHASE ANALYSIS OF COPPER WIRE SAMPLES HEATED BY DIRECT CURRENT

According to statistics, one of the most common causes of vehicle fires is the fire hazard of operating onboard electrical networks - 35%. The most common causes of vehicle fires, during their operation, are malfunctions of electrical equipment (short circuit and overload of on-board electrical wiring) and fuel systems. In this regard, the problem arose to identify the cause and establish the involvement of the ignition of the on-board electrical system and the electrical equipment of the vehicle by studying the microstructures of the conductive elements of the power grid. Microstructures were studied using a method of metallographic and X-ray spectral analysis, using a scanning electron microscope with an X-ray microanalysis system. The microstructure of the reference model of the wire is a copper polycrystal, which is elongated in the direction of deformation. It should be noted that after etching the microstructural heterogeneity is detected, it is observed on both longitudinal and transverse slices. The passage of a direct current through a wire significantly changes its microstructure: in it there are local areas of the globular shape, indicating the melting and subsequent rapid crystallization, resulting in the formation of separate sections in the form of round inclusions. It should be noted that under the influence of short-circuit currents, the gullet form is formed on the surface of the wires, and the dimensional characteristics of the melting regions become larger. In the complex action of the short-circuit of the direct current and the open flame of the model focus on the regions of the melting it becomes noticeable that from the action of the current, due to the sharp heating of the metal formed fine-grained structure, and with the subsequent action of the open flame in the wires formed a large-grained structure, and the action of the flame It is manifested in the fact that the oxidation of the grain boundaries occurs, which results in the destruction of the material of the wire along the grain boundaries. Performing research using the method of local X-ray spectral analysis enables us to determine the oxygen content of copper conductors by the principle of individuality of the spectra and provides sufficiently accurate data on its content in the structure of the conductor, depending on the heating conditions, which confirms the expediency of its use to detect the involvement of the conductors of the onboard electrical grids prior to the occurrence of fires.

Analysis of solutions of automatic exhaust systems for car vehicles

The article contains an analysis of the solutions of automatic fire extinguishing systems used in motor vehicles. Automobile vehicle fires do not occur as often as fires in buildings, but in the event of such a situation pose a threat to people and the environment. The motor vehicle is a conglomerate of combustible materials such as fuel, other combustible liquids and solid equipment materials such as polymers and other plastics. The article is an attempt to systematize and analyze currently used extinguishing devices. The analysis includes used extinguishing media and a review of selected technical solutions of individual systems