Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 15 of 15 for “"HCCI combustion"”.
-
The HCCI Fuel Number - Measuring and Describing Auto-ignition for HCCI Combustion Engines
HCCI is an advanced combustion concept, using premixed fuel and air with a diluted charge. This is thermodynamically favorable, leading to high efficiency and therefore lower CO2 emissions. The well-premixed and diluted fuel charge gives lower cylinder temperatures than conventional diesel …
-
Determination of the effectiveness of a Hot Tube igniter for initiating HCCI combustion
Homogeneous Charge Compression Ignition (HCCI) is a new internal combustion system that promises high efficiency and dramatically reduced nitrous oxide (NOJ and particulate matter (PM) emissions when compared to current spark ignition (SI) and compression ignition (CI) engine technologies. In its …
-
Closed-Loop Control of HCCI Engine Dynamics
… of Homogeneous Charge Compression Ignition (HCCI) engine dynamics. HCCI offers a potential to combine high efficiency with very low emissions. In order to fulfill the potential benefits, closed-loop control is needed. The thesis discusses sensors, feedback signals and actuators for …
-
Characterization of Glow Plug and HCCI Combustion Processes in a Small Volume at High Engine Speed - Load Range, Emission Characteristics and Optical Diagnostics
… halfway to my PhD degree was to understand how HCCI combustion behaves in a small volume at high rotational speed. The investigation has been carried out using a modified model airplane engine. The whole study can be divided into two main parts; in the first, the nature of the glow plug …
-
The combustion and emissions performance of fuel blends in modern combustion systems
The combustion and emissions performance of fuel blends in modern combustion systems has been investigated with the intention of reducing emissions, improving efficiency and assessing the suitability of future automotive fuels. The combustion systems used in this study include Homogeneous Charge …
-
Fuel effects in homogeneous charge compression ignition (HCCI) engines
Homogenous-charge, compression-ignition (HCCI) combustion is a new method of burning fuel in internal combustion (IC) engines. In an HCCI engine, the fuel and air are premixed prior to combustion, like in a spark-ignition (SI) engine. However, rather than using a spark to initiate combustion, the …
-
Effect of ambient conditions and fuel properties on homogeneous charge compression ignition engine operation
… of Homogeneous Charge Compression Ignition (HCCI) combustion must demonstrate robust responses to variations in environmental conditions. This work examines the impact of ambient conditions and fuel changes on HCCI engine operation, and evaluates cam phasing as a mechanism to compensate for …
-
Understanding HCCI characteristics in mini-HCCI engines
… use of Homogeneous-Charge, Compression-Ignition (HCCI) combustion in a standard issue model-aero “diesel” engine. This two-stroke engine, unlike the more common glow-plug versions, operates without any form of combustion initiator. The fuel and air are premixed using a simple carburettor and …
-
Design of a viable homogeneous-charge compression-ignition (HCCI) engine : a computational study with detailed chemical kinetics
The homogeneous-charge compression-ignition (HCCI) engine is a novel engine technology with the potential to substantially lower emissions from automotive sources. HCCI engines use lean-premixed combustion to achieve good fuel economy and low emissions of nitrogen-oxides and particulate matter. …
-
A theoretical assessment of fuel combustion attributes to enhance the operational envelope of HCCI engines
Homogeneous Charge Compression Ignition (HCCI) is an alternative internal combustion (IC) engine that can provide high efficiencies while producing ultra-low nitrous oxides (NOx) and particulate matter (PM) emissions compared to existing compression ignition (CI) and spark ignition (SI) engines. …
-
Two contrasting approaches to auto-ignition modelling for HCCI engines
… models formulated for the emulation of combustion dynamics in Homogeneous Charge Compression Ignition (HCCI) engines. The first (empirical) auto-ignition model was adapted from its previously published form, for HCCI engine model implementation. This model was then combined with an …
-
Optimizing the scavenging system for high efficiency and low emissions: a computational approach
A free piston internal combustion engine operating on high compression ratio, HCCI combustion is being developed to significantly improve the thermal efficiency and exhaust emissions relative to conventional crankshaft-driven SI and Diesel engines. A two-stroke scavenging process recharges the …
-
Combustion modeling for diesel engine control design
… for a computationally efficient modeling of HCCI or PCCI combustion, respectively. The physical domain in the CFD code is subdivided into multiple zones based on three phase variables (fuel mixture fraction, dilution, and total enthalpy). These phase variables are sufficient for the …
-
Turbo Charged Low Temperature Combustion - Experiments, Modeling and Control
… technology involves the use of internal combustion engines in one way or another. Because of the large numbers of internal combustion engines in use around the world, their emissions have a significant environmental impact. Therefore, considerable efforts have been invested into …
-
Non-linear model-based predictive control of a low-temperature gasoline combustion engine
… a non-linear MPC for the lowtemperature gasoline combustion (CAI) in a four-stroke single-cylinder engine. This process must be steered without the actuator of the spark plug. Moreover, smallest changes in the ambient conditions move the self-ignition towards disadvantageous timings and a rough …