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The paper describes the design and operation of a laboratory combustion chamber used to measure the ignition delay times of diesel engine fuels at atmospheric pressure in near quiescent air. The flow apparatus has the means to provide air temperatures in the range between 650 and 730°K which is the typical temperature range at the end of the compression stroke in a diesel engine. An injection pump with a trigger mechanism delivers equal amounts of fuel to an injector, which sprays it into the constantly replensihed supply of fresh, hot air for combustion. An infrared radiation detector monitors the evolution of the temperature inside the combustion chamber. Ignition delay is measured as the time interval between the beginning of the needle lift and the beginning of increase in infrared radiation detected by the sensor. Test results for two fuels are presented and compared with the results from previous studies performed under similar test conditions.

The rate of energy absorption during the plastic deformation of structural components is an important factor in the design of automotive safety systems such as chassis crumple zones. This paper describes a design tool for predicting energy absorption characteristics. The tool was based on measurements of the energy absorption rates of twenty-three selected materials subjected to three impact energy conditions. A well-established finite element code, LS-DYNA3D, was used with a mesh representing a hollow column of square cross-section to establish a database of energy absorption characteristics. A mathematical model representing the energy absorption rates was determined and the material properties most influencing the energy absorption rates were identified. A parabolic model best represented the energy absorption charactersitics. The regression coefficients for the model were determined for all tested materials under the selected test conditions.

The paper* describes the analysis of experimental results of a laboratory flow apparatus used to measure the energy released during premixed combustion at atmospheric pressure in near quiescent air. The flow apparatus, described in a parallel paper, has the means to provide air temperatures in the range between 800 and 950° K. An infrared radiation detector and a photodiode sensitive to radiation in the visible range of the electromagnetic spectrum monitor the events taking place inside the combustion chamber through a sapphire lens. A beam splitter permits simultaneous observation of the combustion events by both sensors. The difference in response times between the two sensors offers information about the non-luminous premixed combustion. Four fuels, No. 2-D diesel fuel, a 50/50% volumetric mixture of diesel fuel and sunflower oil, neat sunflower oil, and neat high oleic safflower oil were used.

The paper* describes the design and operation of a laboratory combustion chamber used to study the energy released during the premixed burning phase of diesel combustion. The flow apparatus operates at atmospheric pressure and has the means to provide near quiescent air at temperatures in the range between 800 and 950° K which is the typical temperature range at the end of compression stroke in a diesel engine. A rotary injection pump with a trigger mechanism delivers equal amounts of fuel to an injector, which sprays it into the constantly replenished supply of fresh, hot air for combustion. An infrared radiation detector and a photodiode sensitive to radiation in the visible range of the electromagnetic spectrum monitor the events taking place inside the combustion chamber through a sapphire lens. A beam splitter permits simultaneous observation of the combustion events by both sensors.