Search Results

In this work, experimental and numerical study was performed to investigate the macroscopic spray structure and the spray characteristics of common rail type high-pressure injector with multi-hole. The global spray structure and microscopic characteristics of high-pressure diesel injector were investigated at various injection and ambient pressures. Spray developing process and spray tip penetration were obtained by spray visualization system, and the quantitative spray characteristics such as local Sauter mean diameter were measured by using phase Doppler particle analyzer. The numerical study was conducted to analyze the atomization characteristics of common-rail type injector at the same conditions with the experiment. In order to improve the prediction accuracy, the numerical analysis was modified using the hybrid breakup model that is composed of primary breakup and secondary breakup.

This paper deals with the Real Time Simulator concerned with entire physical values applied to the automatic climate control for the vehicle, the automatic climate controller and the temperature variation of cabin inside. The control performance is under the characteristics of HVAC system, cabin structure, thermal loads from cabin outside and control algorithm. However, one of the biggest problem with automatic climate control is that it requires a heavy cost and much time for the experimental verification. Moreover, CFD cannot afford to analyze all these values perfectly. For this reason, we solved this problem through the simplified mathematical model and the equations which are evaluated from experimental background. The main objective of this study is to develop a simulator which can replace actual vehicle test on automatic climate control thoroughly.

Exact simulation of conducted EMI in switched mode power supplies is proposed. In order to achieve exact simulations, PSPICE active component ABM model and modified transformer model are proposed. Each model parameter is extracted from measurements and data-books. PSPICE simulation results with high frequency PCB pattern model are accordant with EMI measurements for a 50[W] isolated flyback converter. EMI relations of each component and EMI patterns are analyzed.

A spreadsheet model of a fuel cell was developed for use during the early stages of stack design and development. The model uses a plot of cell potential versus current, referred to as a polarity plot, electrochemical equations, and mass and energy balances to develop relationships among the design and operating variables and the internal fuel cell stack conditions. The model produces the temperature, pressure and humidity profiles for the proposed stack as well as the amount of oxygen in the flow passage. The model is implemented on a spreadsheet which makes it easy to use and quick to change. An example of investigating the feasibility of converting Phosphoric Acid bi-polar plates to a Proton Exchange Membrane fuel cell is presented. The cell dimensions and operating conditions were provided to the model and the temperature variation was calculated. An inlet condition was then altered and the temperature variation recalculated.

A new approach for development of a 50-kW directly solar-pumped iodine laser (DSPIL) system as a space-based power station was made using a confocal unstable resonator (CUR). The CUR-based DSPIL has advantages, such as performance enhancement, reduction of total mass, and simplicity which alleviates the complexities inherent in the previous system, master oscillator/power amplifier (MOPA) configurations. In this design, a single CUR-based DSPIL with 50-kW output power was defined and compared to the MOPA-based DSPIL. Integration of multiple modules for power requirements more than 50-kW is physically and structurally a sound approach as compared to building a single large system. An integrated system of multiple modules can respond to various mission power requirements by combining and aiming the coherent beams at the user's receiver.