CFD-based evaluation of dimethyl carbonate (DMC) combustion in CI diesel engines using experimentally validated models

As the pursuit of sustainable energy solutions intensifies, internal combustion engines (ICEs) continue to play a vital role in heavy-duty transportation and long-distance applications. Within this framework, biofuels have gained prominence as renewable alternatives to conventional diesel, offering the potential to significantly reduce the environmental footprint of existing engine technologies. This study provides a comprehensive numerical assessment of DMC (dimethyl carbonate) in a compression-ignition (CI) engine using a thoroughly validated three-dimensional in-cylinder combustion computational fluid dynamics (3D ICC CFD) model. The model, developed for the Renault F8Q diesel engine, was calibrated against published experimental benchmarks and catalog specifications, ensuring high predictive reliability through extensive sensitivity analyses on mesh resolution, turbulence modeling, transient time-stepping, and heat transfer assumptions. Comparative simulations between standard diesel and the investigated DMC reveal notable shifts in combustion characteristics, performance, and emission trends. While DMC demonstrated lower unburned hydrocarbon and carbon monoxide emissions due to its inherent oxygenated composition, increases in torque and power output were observed due to increased combustion efficiency due to the oxygen in the engine, alongside a tendency for increased nitrogen oxide formation under certain operating conditions.