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Knock is one of the main factors limiting the efficiency of spark-ignition engines. The introduction of alternative fuels with elevated knock resistance could help to mitigate knock concerns. Alcohols are prime candidate fuels and a model that can accurately predict their autoignition behavior under varying engine operating conditions would be of great value to engine designers. The current work aims to develop such a model for neat methanol. First, an autoignition delay time correlation is developed based on chemical kinetics calculations. Subsequently, this correlation is used in a knock integral model that is implemented in a two-zone engine code. The predictive performance of the resulting model is validated through comparison against experimental measurements on a CFR engine for a range of compression ratios, loads, ignition timings and equivalence ratios.

Using liquid alcohols, such as methanol and ethanol, in spark-ignition engines is a promising approach to decarbonize transport and secure domestic energy supply. Methanol and ethanol are compatible with the existing fuelling and distribution infrastructure and are easily stored in a vehicle. They can be used in internal combustion engines with only minor adjustments and have the potential to increase the efficiency and decrease noxious emissions compared to gasoline engines. In addition, methanol can be synthesized from a wide variety of sources, including renewably produced hydrogen in combination with atmospheric CO₂. Presently, during the production of ethanol or methanol a dehydration step is always applied. This step accounts for a significant part of the entire production process' energy consumption and thus, from an economical point of view, methanol and ethanol could become more interesting alternative fuels if the costs related with dehydration could be reduced.