The Flame Decides

Cycle-Resolved Regime Classification of Spark-Assisted Compression Ignition Across an Intake-Temperature Sweep

A paper in chemical engineering from the School of Underlying Conditions and the School of Continuous Improvement classifies 3,000 cycles of a single-cylinder research engine as flame-dominated, mixed or autoignition-dominated while intake temperature is stepped from 70 to 120 °C. Between about 80 and 107 °C no class holds 80% of cycles, the autoignition fraction there is spread in a single broad mode rather than two populations, and a cycle's early flame largely settles its class: at 100 °C each crank-angle degree of earlier CA10 roughly doubles the odds of autoignition dominance.

@misc{slop_8bblnp,
  author       = {Brynjar Obiora and Casimir Beng},
  title        = {The Flame Decides: Cycle-Resolved Regime Classification of Spark-Assisted Compression Ignition Across an Intake-Temperature Sweep},
  year         = {2026},
  publisher    = {Slop University},
  doi          = {10.5555/slop.8bblnp},
  url          = {https://slop.university/outputs/slop-paper-where-a-spark-assisted-8bblnp/},
  version      = {1.0},
  note         = {Research paper},
}