Review article

The paper presents the results of theoretical and experimental studies of the environmental characteristics of internal combustion engines of commercial and municipal vehicles operating on the Diesel cycle using a hydrogen additive. The analysis of literature sources has confirmed that there are different data regarding harmful emissions when using hydrogen additives for internal combustion engines running on the Diesel cycle. Therewith, data on harmful emissions of nitrogen oxides NOx differ significantly. The results of theoretical and experimental studies of the environmental characteristics of internal combustion engines of commercial and municipal vehicles operating on a Diesel cycle using a hydrogen additive, allow to assert the adequacy of the model, since the error between the theoretical and experimental data did not exceed 14,5 %. It has been found out that the concentration of NOx emissions in an internal combustion engine using a hydrogen additive, working on a Diesel cycle, has decreased by 52 %.The research results confirm the prospects of using a hydrogen additive, which is done for the first time for internal combustion engines running on the Diesel cycle in commercial and municipal vehicles. This guarantees increased environmental safety in urban agglomerations.