Search

Introduction. Forensic fire and technical examination of a car is of high demand, and at the same time it is one of the most complicated examinations, because of its complicated nature and need in involvement of experts of various specialties. The design of automobiles and their components is continually improving. In this connection the methodological base of fire and technical examination should be duly adapted to present-day requirement. The safety requirements for prevention of fuel ignitions in a motor cabinet of a car have been analyzed during the research.Materials and Methods. Under the conditions of an accredited laboratory specializing in testing automobile fuels and oils, we have carried out the experiments in ignition of K4-class petrol being fed in drops and stream-like fed on a hot surface. We have also undertaken the experimental studies in order to find out an actual temperature of elements of engine exhaust systems of М1 and М1G automobiles of various models under the actual operating conditions. A thermal imaging camera and a thermocouple have been used to measure the surface temperature of the engine exhaust system parts. An elemental composition of a film formed on a hot steel surface upon contact with petrol has been determined with the use of a scanning electron microscopeResults. We have received the actual results on the temperature of the elements of light car exhaust systems under the various operating conditions. There are the results of experiments on the discharge of the petrol in the form of drops and stream on a hot surface presented in the article. An elemental composition of a film formed on a hot steel surface upon contact with petrol has been analyzed, and secondariness of film formation towards the fire cause has been proved.Conclusion. The results of the research could be used in the conduct of fire and technical examination of vehicles of М1 and М1G categories, what could increase reliability and validity of its conclusions.

Energy carried by engine exhaust pulses is critical to the performance of a turbine or any other exhaust energy recovery system. Enthalpy and exergy are commonly used concepts to describe the energy transport by the flow based on the first and second laws of thermodynamics. However, in order to investigate the crank-angle-resolved exhaust flow enthalpy and exergy, the significance of the flow parameters (pressure, velocity, and temperature) and their demand for high resolution need to be ascertained. In this study, local and global sensitivity analyses were performed on a one-dimensional (1D) heavy-duty diesel engine model to quantify the significance of each flow parameter in the determination of exhaust enthalpy and exergy. The effects of parameter sweeps were analyzed by local sensitivity, and Sobol indices from the global sensitivity showed the correlations between each flow parameter and the computed enthalpy and exergy. The analysis indicated that when considering the specific enthalpy and exergy, flow temperature is the dominant parameter and requires high resolution of the temperature pulse. It was found that a 5% sweep over the temperature pulse leads to maximum deviations of 31% and 27% when resolving the crank angle-based specific enthalpy and specific exergy, respectively. However, when considering the total enthalpy and exergy rates, flow velocity is the most significant parameter, requiring high resolution with a maximum deviation of 23% for the enthalpy rate and 12% for the exergy rate over a 5% sweep of the flow velocity pulse. This study will help to quantify and prioritize fast measurements of pulsating flow parameters in the context of turbocharger turbine inlet flow enthalpy and exergy analysis.

Measurements have been carried out on a four-cylinder spark-ignition engine to estimate the amount of heat recoverable in particular when the engine runs at llow loads. Such heat is sufficient to feed an absorption cooling system for car air conditioning when the speed is over a threshold value. Data for the design of a heat recovery system are reported and discussed. [ABSTRACT FROM AUTHOR]

An automotive air conditioning system based on absorption cycles has been studied. Such a system uses the recovered heat available in the engine exhaust gas. The lithium bromide-water pair is recommended as the working mixture owing to its present technological application level. A possible arrangement of the absorption for this system is proposed. The suitablity of such a system has been investigated, taking operating conditions and other standard requirements into account. Finaly, the particular features of the proposed scheme are pointed out, and a borderline (at least in stationary conditions) is located in the power-velocity diagram. [ABSTRACT FROM AUTHOR]

Energy carried by engine exhaust pulses is critical to the performance of a turbine or any other exhaust energy recovery system. Enthalpy and exergy are commonly used concepts to describe the energy transport by the flow based on the first and second laws of thermodynamics. However, in order to investigate the crank-angle-resolved exhaust flow enthalpy and exergy, the significance of the flow parameters (pressure, velocity, and temperature) and their demand for high resolution need to be ascertained. In this study, local and global sensitivity analyses were performed on a one-dimensional (1D) heavy-duty diesel engine model to quantify the significance of each flow parameter in the determination of exhaust enthalpy and exergy. The effects of parameter sweeps were analyzed by local sensitivity, and Sobol indices from the global sensitivity showed the correlations between each flow parameter and the computed enthalpy and exergy. The analysis indicated that when considering the specific enthalpy and exergy, flow temperature is the dominant parameter and requires high resolution of the temperature pulse. It was found that a 5% sweep over the temperature pulse leads to maximum deviations of 31% and 27% when resolving the crank angle-based specific enthalpy and specific exergy, respectively. However, when considering the total enthalpy and exergy rates, flow velocity is the most significant parameter, requiring high resolution with a maximum deviation of 23% for the enthalpy rate and 12% for the exergy rate over a 5% sweep of the flow velocity pulse. This study will help to quantify and prioritize fast measurements of pulsating flow parameters in the context of turbocharger turbine inlet flow enthalpy and exergy analysis. [ABSTRACT FROM AUTHOR]