Comparative Analysis of Diesel Engine Exhaust Emissions with and without Thermostat Installation

Brilian Vadiansyah; Achmad Ridjanto; Nuril Ahmad

doi:10.59890/ijatss.v4i8.295

Authors

Brilian Vadiansyah Mechanical Engenerin Majapahit Islamic University
Achmad Ridjanto Mechanical Engenerin Majapahit Islamic University
Nuril Ahmad Mechanical Engenerin Majapahit Islamic University

DOI:

https://doi.org/10.59890/ijatss.v4i8.295

Keywords:

Coolant Temperature, Cooling System, Diesel Engine, Exhaust Emission, Thermostat

Abstract

This study examines the exhaust emission characteristics of a diesel engine operating with and without thermostat installation in the cooling system, focusing on carbon monoxide (CO), hydrocarbon (HC), and nitrogen oxide (NOx) emissions. An experimental research design with a comparative approach was employed, in which a single-cylinder diesel engine test unit was tested under two cooling system configurations at a constant engine speed of 1500 rpm using a portable exhaust gas analyzer. The results show that installing the thermostat helped the engine reach a more stable and higher coolant temperature, which improved combustion completeness and reduced CO and HC emissions compared with the condition without a thermostat, although it also led to a slightly higher NOx concentration. These findings indicate that thermostat installation plays an important role in diesel engine thermal management and combustion quality, and that its emission benefits should be balanced with complementary NOx-control strategies for more comprehensive emission reduction

References

Anwar, S. (2019). Effect of Coolant Temperature on Diesel Engine Performance and Emission Characteristics. International Journal of Engineering Inventions, 8(4), 7–17. www.ijeijournal.com

Huang, F., Zhu, Y., Wan, M., Shen, L., Peng, Y., & Xia, D. (2024). Exaust thermal management control of diesel engines via intake throttling coupled with post injection strategy. Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering, 40(2), 196–207. https://doi.org/10.11975/j.issn.1002-6819.202307047

Mancarella, A., & Marello, O. (2023). Effect of Coolant Temperature on Performance and Emissions of a Compression Ignition Engine Running on Conventional Diesel and Hydrotreated Vegetable Oil (HVO). Energies, 16(1). https://doi.org/10.3390/en16010144

Milojević, S., Stopka, O., Kontrec, N., Orynycz, O., Hlatká, M., Radojković, M., & Stojanović, B. (2025). Analytical Characterization of Thermal Efficiency and Emissions from a Diesel Engine Using Diesel and Biodiesel and Its Significance for Logistics Management. Processes, 13(7). https://doi.org/10.3390/pr13072124

Seo, J., Yun, B., Kim, J., Shin, M., & Park, S. (2022). Development of a cold-start emission model for diesel vehicles using an artificial neural network trained with real-world driving data. Science of the Total Environment, 806, 151347. https://doi.org/10.1016/j.scitotenv.2021.151347

Sun, K., Zhang, G., Wang, Z., Li, D., Li, G., Bai, S., Lin, C., & Cheng, H. (2024). Thermal Management of Diesel Engine Aftertreatment System Based on Ultra-Low Nitrogen Oxides Emission. Applied Sciences (Switzerland), 14(1). https://doi.org/10.3390/app14010237

Suryapradana, I., & Halim, A. (2024). Analysis of Application of the Thermostat in the Cooling System of the Nissan CWB 45 Dump Truck Engine. Sebatik, 28(2), 313–319. https://doi.org/10.46984/sebatik.v28i2.2496

Turabimana, P., Sohn, J. W., & Choi, S. B. (2023). A Novel Active Cooling System for Internal Combustion Engine Using Shape Memory Alloy Based Thermostat. Sensors, 23(8). https://doi.org/10.3390/s23083972

Zacharewicz, M., Zadrąg, R., Bogdanowicz, A., Socik, P., Wirkowski, P., & Hołownia, J. (2024). Evaluation of the impact of the thermal state of a diesel engine on its efficiency. Combustion Engines, 196(1), 30–36. https://doi.org/10.19206/CE-170793