Combustion Diagnostics by Means of Multizone Heat Release Analysis and NO Calculation
Author
Summary, in English
In this paper a combustion diagnostic method is presented
where measured pressure data is used to calculate the heat release, local temperatures and concentrations of NO and other species. This is done by a multizone model where the lambda value, i.e. 1/equivalence ratio, in each zone can be chosen arbitrarily. In homogenous charge engines lambda is given by the global air/fuel ratio. The local lambdas during initial combustion in stratified charge and diesel engines have to be estimated either as an average value or with a chosen distribution.
One new zone of each local lambda is generated and the temperature, volume and species in all old zones are updated at each time step of calculation. In this paper the
model is demonstrated by using pressure data from premixed
and direct injected stratified charge natural gas SI engines and from a DI diesel engine.
The pre-mixed data is used to validate the model as such
while the ambition in the stratified charge and diesel
cases has been to find the average local lambda that gives the same NOx emission as measured. The emphasis in the latter cases has been to study the influence on average local lambda of the duration of the fuel injection. Early injected fuel seems to burn at slightly leaner mixtures
than later injected.
where measured pressure data is used to calculate the heat release, local temperatures and concentrations of NO and other species. This is done by a multizone model where the lambda value, i.e. 1/equivalence ratio, in each zone can be chosen arbitrarily. In homogenous charge engines lambda is given by the global air/fuel ratio. The local lambdas during initial combustion in stratified charge and diesel engines have to be estimated either as an average value or with a chosen distribution.
One new zone of each local lambda is generated and the temperature, volume and species in all old zones are updated at each time step of calculation. In this paper the
model is demonstrated by using pressure data from premixed
and direct injected stratified charge natural gas SI engines and from a DI diesel engine.
The pre-mixed data is used to validate the model as such
while the ambition in the stratified charge and diesel
cases has been to find the average local lambda that gives the same NOx emission as measured. The emphasis in the latter cases has been to study the influence on average local lambda of the duration of the fuel injection. Early injected fuel seems to burn at slightly leaner mixtures
than later injected.
Department/s
Publishing year
1998
Language
English
Publication/Series
SAE technical paper series
Volume
107
Full text
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Document type
Journal article
Publisher
Society of Automotive Engineers
Topic
- Other Mechanical Engineering
Keywords
- Multi Zone
- NO
- Heat Release
- Cylinder Pressure
- Combustion
- Engine
Status
Published
ISBN/ISSN/Other
- ISSN: 0148-7191