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An Arbitrary Lagrangian Eulerian (ALE) approach was adopted in this study to predict the responses of side crash pressure sensors in an attempt to assist pressure sensor algorithm development by using computer simulations. Acceleration-based crash sensors have traditionally been used to deploy restraint devises (e.g., airbags, air curtains, and seat belts) in vehicle crashes. The crash pulses recorded by acceleration-based crash sensors usually exhibit high frequency and noisy responses depending on the vehicle's structural design. As a result, it is very challenging to predict the responses of acceleration-based crash sensors by using computer simulations, especially those installed in crush zones. Therefore, the sensor algorithm developments for acceleration-based sensors are mostly based on physical testing.

This work presents a study of crash energy and severity in frontal offset Vehicle-To-Vehicle (VTV) crash tests. The crash energy is analyzed based on analytical formulations and empirical data. Also, the crash severity of different VTV tests is analyzed and compared with the corresponding full frontal rigid barrier test data. In this investigation, the Barrier Equivalent Velocity (BEV) concept is used to calculate the initial impact velocity of frontal offset VTV test modes such that the offset VTV tests are equivalent to full frontal impact tests in terms of crash severity. Linear spring-mass model and collinear impact assumptions are used to develop the mathematical formulation. A scale factor is introduced to account for these assumptions and the calculated initial velocity is adjusted by this scale factor. It is demonstrated that the energies due to lateral and rotational velocity components are very small in the analyzed frontal VTV tests.

1 The fluid spray exits the nozzle in the form of a stream, which decays rapidly to ligaments that break up into droplets. All these transitions occur in a very short time and region. This work provides a fundamental analysis of the jet stability in general form, but it is devoted particularly to fluidic jets. Such jets exist in different industrial applications; automobile windshield washer and diesel fuel injector sprays are good examples. A computational analysis is developed that predicts the break up distance and velocity of the fluidic jets, which is one of the important factors that helps in prediction of the spray pattern and droplet strike location. Thus reduces number of the required prototypes and saves time and cost. Also, a parametric study is conducted to analyze the effect the jet breakup on the spray trajectory.

This research provides a fundamental study of the fluid mechanics of an automobile washer spray system from the reservoir to the windshield. A computational model is developed that specifies the strike location of the washer spray on the windshield. The model is useful to designers as an initial locator for nozzles, thus reducing wind-tunnel and road test time. A new algebraic model predicting the frequency and exit velocity of fluidic devices is successfully developed. It is generated by applying design of experiment and statistical regression analysis on a set of computational experimental data. The two phase flow (air and washer liquid) is modeled using the source panel method for the air flow and Newton’s Second Law to track the spray droplets. The numerical scheme is designed to simplify the complexity of the two-phase flow analysis and is thus computationally economical. The computational results have been compared with experimental tests.