Reduction mechanism of NOx derived from post injection

Yukito Watanabe (YANMAR Holdings)･Yoji Hiraiwa (Hokkaido University Graduate School of Engineering)･Gen Shibata･Hideyuki Ogawa (Hokkaido university Research faculty of engineering)

It has been reported that post-injection in diesel engines has a NOx reduction effect, but the detailed mechanism remains unclear. In this study, the NOx reduction effect of post-injection was investigated in detail through engine experiments, and the potential for NOx reduction by ammonia generated during combustion was analyzed using zero-dimensional chemical kinetics calculations.

Estimation of Gas Temperature in Intake System of a Diesel Engine Using Modeling Method Based on Machine Learning

Takato Ikedo･Yoshifumi Wakisaka (Toyota Central R&D Labs.)

This report proposes a model to estimate gas temperature in intake system of a diesel engine with high accuracy for the purpose of improving fuel consumption and reducing emissions by optimizing the control of diesel engine. The proposed model combines neural network and physics, and it is based on the energy conservation law and the mass conservation law in order　to estimate gas temperature in intake system. As a result of evaluating the estimation accuracy for the test data created using virtual diesel engine data, the mean absolute error in all sections was 0.692 degC.

Proof of advanced emission control systems and thermal strategies for future NRMM regulations

Bernhard Raser (AVL List)･Joachim Demuynck･Dirk Bosteels (AECC)･Hannes Noll (AVL List)

The regulation of pollutant emissions for Non-Road Mobile Machinery is under review in the US (CARB Tier 5 proposal) and EU (Stage V review). Future regulations are expected to emphasize diverse operating conditions, including continuous low load. CO2-neutral fuels are being explored to mitigate the carbon footprint of NRMM Internal Combustion Engines (ICE), a key powertrain for the sector. This study evaluates NOx and CO2 reduction potential using an NRMM engine model simulation across test cycles (NRTC, NRSC, LLC) and in-use scenarios. Additionally, test results of an NRMM engine are presented, examining various future exhaust emission control systems combined with advanced engine temperature management strategies. These findings demonstrate the potential for optimizing pollutant reduction technologies and thermal management to meet stringent future emissions standards while maintaining performance and efficiency.

Optical Analysis of Mixture Formation by Spraying Urea-Emulsion Fuel

Ryosuke Takeda･Daisuke Oda･Akihiro Kido (Tohoku Gakuin Univercity)

Conventional emulsion fuel used water, in contrast in this study used urea water mixture. The results of this study provide insight into the mixture formation characteristics of urea- emulsion by comparing it with gasoline and diesel fuels, which are currently the mainstream fuels, and ammonia and emulsion fuels, which are attracting attention as alternative fuel to petroleum, and their respective fuel spraying.

Evaluation of Urea-added Emulsion Fuels by Chassis Dynamometer Tests using an IDI Diesel Engine Vehicle

Daisuke Oda･Ryosuke Takeda･Akihiro Kido (Tohoku Gakuin University)

The Ammonia, which can be generated from renewable energy, has been attracting attention towards achieving carbon neutrality in internal combustion engine vehicles. And a Urea synthesized by ammonia is easy to handle. In this study, various performances of urea-added emulsion fuels when applied to a diesel engine with sub-chamber were evaluated using a chassis dynamometer test.