| Experimental and Simulated Results Detailing the Sensitivity of Natural Gas HCCI Engines to Fuel Composition |
| Journal & Paper No: |
| SAE Paper 2001-01-3609 |
| Authors: |
| Scott B. Fiveland, Rey Agama, Magnus Christensen, Bengt Johansson, Joel Hiltner, Fabian Mauss, Dennis N. Assanis |
| Abstract: |
Natural
gas quality, in terms of the volume fraction of higher hydrocarbons,
strongly affects the auto-ignition characteristics of the air-fuel
mixture, the engine performance and its controllability. The influence
of natural gas composition on engine operation has been investigated
both experimentally and through chemical kinetic based cycle simulation.
A range of two component gas mixtures has been tested with methane
as the base fuel. The equivalence ratio (0.3), the compression
ratio (19.8), and the engine speed (1000 rpm) were held constant
in order to isolate the impact of fuel autoignition chemistry.
For each fuel mixture, the start of combustion was phased near
top dead center (TDC) and then the inlet mixture temperature was
reduced. These experimental results have been utilized as a source
of data for the validation of a chemical kinetic based full-cycle
simulation. Results reported here clearly demonstrate the ability
of a thermo-kinetic, single-zone model to capture the fuel composition
effects seen in the experiments. The uncertainty that exists in
both the experiment and simulation is discussed in light of the
model predictions. This uncertainty is used to quantify what reasonable
level of accuracy can be expected between a model and experiment
under HCCI operation. Finally, the simulation has been further
exercised to compute the sensitivity of ignition timing to changes
in hydrocarbon composition outside what has been experimentally
tested. |
| Paper: P2001_05.PDF |
Copyright
2008
University of Michigan