Sökning: "compression ratio"
Visar resultat 16 - 20 av 132 avhandlingar innehållade orden compression ratio.
16. Deformation and failure of brittle rocks under compression
Sammanfattning : This thesis describes the deformation and failure of rocks under compression through a micromechanics model and laboratory studies of the Kaiser effect. It comprises an overview and seven appended papers. The deformation model is developed based on the analysis of the behaviour of microcracks. LÄS MER
17. Optical Diagnostics for Engine Efficiency in Gasoline Compression Ignition
Sammanfattning : The internal combustion engine has played a significant role in a vast number of applications from small cars to giant tankers, setting people free from geographical barriers and heavy labor. However, it has also generated many tons of harmful emissions and CO2that damage to humans and the environment. LÄS MER
18. Characterization of the Homogeneous Charge Compression Ignition Combustion Process
Sammanfattning : The main objective of this project was to characterize the HCCI combustion process. Central parts in the project were the progress of the HCCI combustion process, the influence of charge homogeneity on the combustion process and sources of UHC and CO emissions in HCCI combustion. LÄS MER
19. Modelling for Fuel Optimal Control of a Variable Compression Engine
Sammanfattning : Variable compression engines are a mean to meet the demand on lower fuel consumption. A high compression ratio results in high engine efficiency, but also increases the knock tendency. On conventional engines with fixed compression ratio, knock is avoided by retarding the ignition angle. LÄS MER
20. CFD Modelling of a Free-Piston Engine Using Detailed Chemistry
Sammanfattning : The Free Piston Engine, FPE, which is capable of operating in a variable compression ratio mode, is highly suitable for the promising Homogeneous Charge Compression Ignition (HCCI) concept, allowing flexible auto-ignition control on a cycle-to-cycle basis without any hardware modifications. In this study, the effects of varying the start of injection on the emission formation and efficiency of such an engine have been investigated, using simulations based on the KIVA-3V CFD code. LÄS MER