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Title: Cycle-by-cycle combustion variations in spark-ignited engines

Conference ·
OSTI ID:522755
 [1];  [2];  [3]
  1. Oak Ridge National Lab., TN (United States)
  2. Univ. of Tennessee, Knoxville, TN (United States). College of Engineering
  3. Ford Motor Company, Dearborn, MI (United States); and others

Under constant nominal operating conditions, internal combustion engines can exhibit substantial variation in combustion efficiency from one cycle to the next. Previous researchers have attempted to explain these variations as resulting from stochastic, linear, or chaotic physical processes. Our investigations indicate that cyclic combustion variations can be explained as the result of interactions between a global low-dimensional nonlinearity and small-scale, high-dimensional processes that perturb the nonlinearity. Using this approach, we have proposed a simple model that accurately simulates experimentally observed patterns in cyclic combustion variations. Our model also explains the apparent discrepancies among previous investigators regarding the basic nature of cyclic variations. Further, it appears that symbol dynamics are useful for characterizing the observed model and experimental behavior.

Research Organization:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Organization:
USDOE Office of Energy Research, Washington, DC (United States)
DOE Contract Number:
AC05-96OR22464
OSTI ID:
522755
Report Number(s):
CONF-970851-1; ON: DE97008566; TRN: 97:005059
Resource Relation:
Conference: 4. experimental chaos conference, Boca Raton, FL (United States), 6-8 Aug 1997; Other Information: PBD: 1997
Country of Publication:
United States
Language:
English