The study presents a one-dimensional, transient and compressible flow models of a commercial Common Rail Injector (CRI) and a prototype of a single-fuel Hydraulically actuated Electrically controlled Unit Injector (HEUI) developed at the University of New South Wales (UNSW) in conjunction with local industry. The unique feature of the UNSW HEUI is the fact that it uses diesel fuel as the driver for pressure amplification within the unit injector. The work undertaken is part of a wider study aimed at optimization of the design of diesel injectors for dual-fuel systems to reduce green house gas emissions. The contribution of this thesis is the development of the model of the UNSW HEUI injector, which can be used to investigate possible modifications of the injector for its use in dual-fuel injection systems. The developed models include electrical, mechanical and hydraulic subsystems present in the injectors. They are based on Kirchhoff??s laws, on the mass and momentum conservation equations and on the equilibrium of forces. The models were implemented in MATLAB/SIMULINK graphical software environment, which provides a high degree of flexibility and allows simulation of both linear and nonlinear elements. The models were used to perform sensitivity analysis of both injectors. The sensitivity analysis has revealed that the temperature of the solenoid coil is one of the critical parameters affecting the timing and the quantity of the fuel injection of both injectors. Additional critical parameters were found to be the dimensions of the piston of the CRI, the stiffness of the needle spring of the HEUI and the dimensions of the intensifier of the HEUI. The models also revealed that in the case of pilot injections the speed of the solenoid is the major limiting factor of the performance. The developed models provide better understanding of the issues and limitations of the injectors. They give detailed insight into their working principles. The investigations of the models permit making quantitative analysis of the timing of the HEUI solenoid and to evaluate the proposed change of the direction of the pressure acting on the HEUI solenoid plunger.

Our nation is faced with a shortfall in funding desired transportation improvement programs. Texas is one of many states currently at crisis level as it is faced with an estimated annual funding shortfall of about $7 billion dollars between projected needs and transportation fund availability. This is a result of increased vehicle miles traveled and significant population growth that has outpaced the state’s transportation fund availability. Not only is the Texas transportation system declining in quality, but it is rapidly falling behind in the quantity needed to maintain current quality of life. As the Texas Mobility Fund balance approaches zero, the state needs to look toward non-traditional financing mechanisms to address its revenue shortfall. This report examines the problems associated with increased transportation demands in Texas and financing the expansion and maintenance of the state’s transportation system. / text

The main aim of this work is a development of electric car. This car has fuel cells as a primary source of electrical energy which will be performed with regard to the maximum roll-out and to maximize the efficiency of hydrogen conversion into electricity. The first part is dedicated to the concept of drive as a whole, the second part is dedicated to solving vehicle dynamics. The third part describes the design of mathematical models of drive components. Part four gives the results of simulations of traffic on the route at different ways of managing fuel cells and various vehicle speeds.

This diploma thesis is focused on examining the development of a diesel tractor engine with a newer injection system, concretely common-rail system. Mainly it is about the application of the high pressure fuel pump, fuel rail and injectors. With regard to the used components are appropriate adjustments made on the engine, and then checked using the available calculations. Brief mention is given to the theoretical summary of the contemporary state of applied injection system and its development trend. Selecting adjustments is primarily based on observed operating load. However, it is also striving to their simplest implementation. An integral part of this work is drawing documentation of newly designed components.

Thesis (MScEng (Mechanical and Mechatronic Engineering))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: This thesis comprises of the testing and evaluation of a modern diesel engine running on both biodiesel and mineral diesel on the upgraded Bio-fuels Testing Facility (BTF) at Stellenbosch University. The project was motivated by the need to install a modern diesel engine onto the existing BTF test rig for biodiesel testing. In this project, the BTF was re-designed to support a new Volkswagen 1.9L TDI engine. The capabilities of the BTF were then expanded further by the implementation of a low-cost pressure indicating system, utilising an optical pressure transducer. During the testing of biodiesel, it was found that the calorific value of the biodiesel was 14% lower than that of the tested mineral diesel. The ignition quality (cetane index) of the biodiesel was also lower than that of the mineral diesel. Even so, the engine only experienced a maximum power loss of 4.2%. During heat-release analysis, it was determined that there was no significant difference in the combustion process of biodiesel and that of mineral diesel. The conclusion could be made that biodiesel is suitable for use in modern TDI engines. Testing validated the operation of the upgraded test cell, and in trials it was determined that the test results are highly repeatable. The pressure indicating set proved to have some limitations. Only simplified heat-release analyses and reasonable indicated power calculations could be performed with the indicating set. Recommendations were made for improvement in future research. / Centre for Renewable and Sustainable Energy Studies

The aim of this diploma thesis is to draw up a business plan regarding an extension of an existing car repair service by adding a public fuel filling station to it. The public fuel filling station will be built directly within the area of the existing car repair service located in the village of Jemnice, in the district of Žďár nad Sázavou. The theoretical part generally describes the business activity, possible forms of business and individual analyses used in this diploma thesis. The second part briefly describes the chosen company, for which the above mentioned draft of the businnes plan is intended. The last part of the diploma thesis presents the actual construction plan of the public fuel filling station based on the elaborated analyses, including the time schedule of the execution.

This work focuses on the cooling of diesel engines. Facing heavy constraints such<p>as emissions control or fossil energy management, political leaders are forcing car<p>manufacturers to drastically reduce the fuel consumption of passenger vehicles. For<p>instance, in Europe, this fuel consumption has to reach 120 g CO2 km by 2012, namely 25 % reduction from today's level.<p>Such objectives can only be reached with an optimization of all engines components<p>from injection strategies to power steering. A classical energy balance of an internal<p>combustion engine shows four main losses: enthalpy losses at the exhaust, heat<p>transfer to the cylinder walls, friction losses and external devices driving. An<p>optimized cooling will improve three of them: the heat transfer losses by increasing<p>the cylinder walls temperature, the friction losses by reducing the oil viscosity and<p>the coolant pump power consumption.<p>A model is first built to simulate the engine thermal behavior from the combustion<p>itself to the temperatures of the different engine components. It is composed by two<p>models with different time scales. First, a thermodynamic model computes the in cylinder<p>pressure and temperature as well as the heat flows for each crank angle.<p>These heat flows are the main input parameters for the second model: the nodal<p>one. This last model computes all the engine components temperatures according<p>to the nodal model theory. The cylinder walls temperature is then given back to<p>the thermodynamic model to compute the heat flows.<p>The models are then validated through test bench measurements giving excellent<p>results for both Mean Effective Pressure and fluids (coolant and oil) temperatures.<p>The used engine is a 1.9l displacement turbocharged piston engine equipped with<p>an in-cylinder pressure sensor for the thermodynamic model validation and thermocouples<p>for the nodal model validation.<p>The model is then used to optimize the coolant mass flow rate as a function of<p>the engine temperature level. Simulations have been done for both stationary<p>conditions with effciency improvement up to 7% for specific points (low load, high<p>engine speed) and transient ones with a heating time improvement of about 2000s.<p>This gains are then validated on the test bench showing again good agreement. / Doctorat en Sciences de l'ingénieur / info:eu-repo/semantics/nonPublished