Use this URL to cite or link to this record in EThOS:
Title: Measurement of liquid fuel within the cylinder of a spark ignition engine
Author: Taylor, Greg
Awarding Body: UCL (University College London)
Current Institution: University College London (University of London)
Date of Award: 2005
Availability of Full Text:
Access from EThOS:
Full text unavailable from EThOS. Please try the link below.
Access from Institution:
It is appreciated that the deposition of liquid gasoline on the wall of the cylinder liner is known to be detrimental to the life of an SI engine. Liquid fuel on the combustion chamber and cylinder liner surfaces may lead to an increase in hydrocarbon emissions, particularly during cold-start operation. In addition, liquid fuel on the cylinder bore may wash the protective oil film from the surface liner, making it vulnerable to increased wear and chemical attack by the corrosive combustion chamber products (the latter particularly true when the liner surface is still cold, promoting the condensation of acids). Finally, liquid fuel on the cylinder wall may pass the piston rings, particularly when clearances are at their largest, causing high rates of 'lost fuel' to the crankcase and dilution of the crankcase oil. In 1997 BMW admitted they had a problem with their small capacity 6-cylinder engines. BMW was forced to retrofit customer cars with new engines after relatively low mileage and change the design of the engine from Nikasil coated aluminium liners to a more durable cast iron liner. Nikasil coated liners are particularly vulnerable due to the fact that the nickel coating is relatively thin. If wear of the cylinder wall exceeds the 80-micron coating thickness, then the softer aluminium backing material is exposed and wear is accelerated. The Jaguar AJV8 engine employs Nikasil liners similar to those used by BMW. There has been no published information suggesting that there is a bore wear concern with the Jaguar AJV8. However, being able to evaluate the deposition of liquid fuel of the cylinder wall of an engine during the development process would be extremely valuable. This thesis details the instrumentation, tools and techniques which can be used for such analysis. The results obtained provide an insight into the wall wetting characteristics of a number of four-valve cylinder head designs. There is an absence of such information in the scientific literature. This research suggests that the engine geometries tested in this work should not suffer from any durability concerns related to bore wetting.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available