Hydrogen Fuel Addition in Diesel Engines: Current and Future Research Trends through Bibliometric Analysis

Eswanto; Mohd Adnin Hamidi; Sarbani Daud; Ahmad Fitri Yusop; Moaz  Allehaibi

doi:10.57159/jcmm.5.3.26566

Authors

Eswanto Faculty of Mechanical and Automotive Engineering Technology, Universiti Malaysia Pahang Al-Sultan Abdullah, Pahang, Malaysia; Mechanical Engineering, Universitas Negeri Medan, Medan, Indonesia https://orcid.org/0000-0003-1924-6716
Mohd Adnin Hamidi Faculty of Mechanical and Automotive Engineering Technology, Universiti Malaysia Pahang Al-Sultan Abdullah, Pahang, Malaysia; Pusat Kejuruteraan Automotif, Universiti Malaysia Pahang Al-Sultan Abdullah, Pahang, Malaysia https://orcid.org/0000-0002-0916-8155
Sarbani Daud Faculty of Mechanical and Automotive Engineering Technology, Universiti Malaysia Pahang Al-Sultan Abdullah, Pahang, Malaysia; Pusat Kejuruteraan Automotif, Universiti Malaysia Pahang Al-Sultan Abdullah, Pahang, Malaysia https://orcid.org/0000-0003-1170-409X
Ahmad Fitri Yusop Faculty of Mechanical and Automotive Engineering Technology, Universiti Malaysia Pahang Al-Sultan Abdullah, Pahang, Malaysia; Pusat Kejuruteraan Automotif, Universiti Malaysia Pahang Al-Sultan Abdullah, Pahang, Malaysia https://orcid.org/0000-0002-5449-3766
Moaz Allehaibi Faculty of Mechanics and Mathematics, Moscow Lomonosov State University, Moscow, Russia

DOI:

https://doi.org/10.57159/jcmm.5.3.26566

Keywords:

Hydrogen, Diesel Engine, Bibliometric Analysis, VOSviewer, Fuel Addition

Abstract

Purpose: This study maps recent research trends on hydrogen fuel addition in diesel engines through a bibliometric analysis of Scopus-indexed publications, aiming to identify trends and developments in hydrogen utilization as a fuel mixture in diesel combustion.
Methods: Publications documented between 01 January 2021 and 30 May 2025 were retrieved from the Scopus database. VOSviewer was applied to map research trends by analyzing citation frequencies, leading authors, collaboration networks, and publication patterns across countries.
Results: The analysis shows a maximum citation count of 120 across seven publications, with India emerging as the most productive nation in this field. Current research trends highlight dual-fuel diesel engines, combustion efficiency, and emission characteristics as dominant themes.
Conclusions: Future research is projected to expand toward tri-fuel modes, hydrogen blending ratios, alternative fuels, reactivity-controlled compression ignition (RCCI), applications in marine diesel engines, and hydrogen storage and distribution technologies. These findings help researchers define roles and focus areas to strengthen discourse on hydrogen in diesel engines, contributing to sustainable advancements in hydrogen fuel research.

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