Emission Characteristics of Heavy-Duty Vehicle Diesel Engines at High Altitudes

Document Type : Regular Article


CATARC Automotive Test Center (Kun Ming) Co., Ltd. Kunming, Yunnan 651701, China



The aim of this study was to accurately quantify the emission characteristics of pollutants at different altitudes. We used an intake and exhaust altitude simulation system that could simulate the intake and exhaust pressures of a national sixth vehicle diesel engine at different altitudes. Experimental research was conducted on the World Harmonized Transient Cycle (WHTC) and World Harmonized Steady State Cycle (WHSC) of the diesel engine. The results showed that carbon monoxide (CO) emissions increased with the altitude at full load, but their rates were significantly reduced at low speed (800 rpm), increasing by 0.0084–0.665 ppm/m. Hydrocarbon (HC) emissions showed an initial decreasing and then increasing trend, with a rise of up to 30%. Nitrogen oxides (NOx) showed a linear decreasing trend, especially at low speed. With the increase in altitude, the cycle work of the diesel engine decreased in a non-linear manner, and the decrease became more pronounced above 3000 m. The raw emission results of the WHTC and WHSC tests also revealed that CO increased exponentially, NOx decreased slightly and then increased rapidly, HC increased linearly, and the emissions of all pollutants deteriorated significantly above 3000 m. The exhaust emission results of the WHTC and WHSC tests showed that the CO emission showed an initial decreasing and then increasing trend with the elevation of the altitude, approximately 15 ± 5 mg/kWh. HC emissions showed an increasing trend, with HC emissions of 3 – 6 mg/kWh for the WHTC and 1 – 2 mg/kWh for the WHSC. NOx emissions did not follow any obvious rule, while the particulate matter (PM) tended to increase and then decrease with the elevation of the altitude. In relation to the current emission standards, the limit value margin for CO and HC exhaust emissions is greater than 95% and the limit value margin for PM emissions is greater than 88% at an altitude of 4000 m. The NOx emission limit is greater than 87% (within 3000 m), but there is a risk of exceeding the limit above 3000 m. The second sampling data from the WHTC and WHSC showed that the raw emissions of the engine were higher in the high-altitude area than in the low-altitude area, but the change law of the exhaust emissions was not obvious, and the levels of both emissions were low.


Main Subjects

Agarwal, A., Kumar, V., Kalwar, A.&  Kalwar, A. (2022). Fuel injection strategy optimisation and experimental performance and emissions evaluation of diesel displacement by port fuel injected methanol in a retrofitted mid-size genset engine prototype. Energy, 248, 123593. https://doi.org/10.1016/J.ENERGY.2022.123593
Benjumea, P., Agudelo J. & Agudelo A. (2009). Effect of altitude and palm oil biodiesel fuelling on the performance and combustion characteristics of a HSDI diesel engine. Fuel, 88, 725–731. https://doi.org/10.1016/j.fuel.2008.10.011
Bo, Y. Q., Liu, F. S., Wu, H. & Li, H. Y. (2021). A numerical investigation of injection pressure effects on wall-impinging ignition at low-temperatures for heavy-duty diesel engine. Applied Thermal Engineering, 184, 116366. https://doi.org/10.1016/j.applthermaleng.2020.116366
Chaffin, C. A., & Ullman T. L. (1994). Effects of increased altitude on heavy-duty diesel engine emissions. SAE Technical Paper, 1, 940669. https://doi.org/https://doi.org/10.4271/940669
Chen, H., He, L., Chen J. & Yuan, B. (2019). Impacts of clean energy substitution for polluting fossil-fuels in terminal energy consumption on the economy and environment in China. Sustainability, 11, 6419. https://doi.org/10.3390/su11226419
Duan, X., Fu, J., Zhang, Z. & Liu, J. (2017). Experimental study on the energy flow of a gasoline-powered vehicle under the NEDC of cold starting. Applied Thermal Engineering, 115, 1173–1186. https://doi.org/10.1016/j.applthermaleng.2016.10.002
Fang, L., Lou, D. M., Hu, Z. Y. & Tan, P. Q. (2022). Study on the First-Firing-Cycle combustion characteristics of high-altitude and low-temperature environments during diesel engine cold start. Fuel, 322, 124186. https://doi.org/10.1016/j.fuel.2022.124186
Fenger, J. (2009). Air pollution in the last 50 years–from local to global. Atmospheric Environment 43, 13–22. https://doi.org/10.1016/j.atmosenv.2008.09.061
Gallagher, K., Zhang, F., Orvis, R., & Rissman, J. (2019) Assessing the policy gaps for achieving china’s climate targets in the paris agreement. Nature Communications 10, 1256. https://doi.org/10.1038/s41467-019-09159-0
Giraldo, M., & Huertas, J. I. (2019). Real emissions, driving patterns and fuel consumption of inuse diesel buses operating at high altitude. Transportation Research Part D-transport and Environment, 77, 21–36. https://doi.org/10.1016/j.trd.2019.10.004
Greene, S., & Façanha, C. (2019). Carbon offsets for freight transport decarbonization. Nature Sustainability, 2, 994–996. https://doi.org/10.1038/s41893-019-0413-0
Hamedi, M. R., Tsolakis, A. & Herreros, J. M. (2014). Thermal performance of diesel aftertreatment: material and insulation CFD analysis. SAE Technical Paper, 1, 2818. https://doi.org/10.4271/2014-01-2818
Jiao, Y. F., Liu, R. L., Zhang, Z. J. & Yang, G. M. (2019). Comparison of combustion and emission characteristics of a diesel engine fueled with diesel and methanol Fischer Tropsch diesel biodiesel diesel blends at various altitudes. Fuel, 243, 52–59. https://doi.org/10.1016/j.fuel.2019.01.107
Kelly, F. J., & Fussell, J. C. (2012). Size, source and chemical composition as determinants of toxicity attributable to ambient particulate matter. Atmospheric Environment, 60, 504–526. https://doi.org/10.1016/j.atmosenv.2012.06.039
Kim, C. H., Paratore, M., Gonze, E. & Solbrig, C. (2012). Electrically heated catalysts for cold-start emissions in diesel aftertreatment. SAE Technical Paper 1, 1092. https://doi.org/10.4271/2012-01-1092
Li, Y., Wen, C., Luo, Z. & Jin, L. (2022). Dynamic characteristics analysis of a dual-rotor system with bolted-disk joint. Proceedings of the Institution of Mechanical Engineers Part C-Journal of Mechanical Engineering Science, 214, 1040473. https://doi.org/10.1177/09544062221123988
Liu, J. L., Li, Y. Y., Zhang, C. H. & Liu, Z. T. (2022). The effect of high altitude environment on diesel engine performance: Comparison of engine operations in Hangzhou, Kunming and Lhasa cities. Chemosphere, 309, 136621. https://doi.org/10.1016/j.chemosphere.2022.136621
Liu, J., Ge, Y., Wang, X. & Hao, L. (2017). On-board measurement of particle numbers and their size distribution from a light-duty diesel vehicle: Influences of VSP and altitude. Journal of Environmental Sciences, 57, 238–248. https://doi.org/10.1016/j.jes.2016.11.023
Liu, R., Zhang, Z., Dong, S. & Zhou, G. (2017). High-altitude matching characteristic of regulated two-stage turbocharger with diesel engine. Journal of Engineering for Gas Turbines and Power-Transactions of the Asme, 39, 094501. https://doi.org/10.1115/1.4036283
Liu, Z. T., & Liu, J. L. (2021). Effect of altitude conditions on combustion and performance of a turbocharged direct-injection diesel engine. Proceedings of the Institution of Mechanical Engineers Part D-Journal Automobile Engineering, 1–12. https://doi.org/10.1177/09544070211026204
Liu, Z. Q., Chen, J. Y., Su, Z. J. & Liu, Z. X. (2023). Acid rain reduces plant-photosynthesized carbon sequestration and soil microbial network complexity. Science of Total Environment, 873, 162030. https://doi.org/10.1016/j.scitotenv.2023.162030
Motahari, S., & Chitsaz, I. (2019). Effects of altitude and temperature on the performance and efficiency of turbocharged direct injection gasoline engine. Journal of Applied Fluid Mechanics, 12, 1825–1836. https://doi.org/10.29252/jafm.12.06.29862
Nie, X., Bi, Y. H., Liu, S. H. & Shen, L. Z. (2022). Impacts of different exhaust thermal management methods on diesel engine and SCR performance at different altitude levels. Fuel, 324, 124747. https://doi.org/10.1016/j.fuel.2022.124747
Rounce, P., Tsolakis, A. & York, A. (2012). Speciation of particulate matter and hydrocarbon emissions from biodiesel combustion and its reduction by aftertreatment. Fuel, 96, 90–99. https://doi.org/10.1016/j.fuel.2011.12.071
Sayed, E. T., Wilberforce, T., Elsaid, K. & Rabaia, M. H. (2021). A critical review on environmental impacts of renewable energy systems and mitigation strategies: Wind, hydro, biomass and geothermal. Sci Total Environ, 766, 144505. https://doi.org/10.1016/j.energy.2020.118987
Serrano, J. R., Piqueras, P., Abbad, A. & Tabet, R. (2019). Impact on reduction of pollutant emissions from passenger cars when replacing Euro 4 with Euro 6d diesel engines considering the altitude influence. Energies, 12, 1278. https://doi.org/10.3390/en12071278
Shannak, B. A., & Alhasan, M. (2002). Effect of atmospheric altitude on engine performance. Forsch Ingenieurwes, 67, 157–160. https://doi.org/10.1007/s10010-002-0087-y
Shi, Z., Lee, C. F., Wu, H. & Wu, Y. (2019). Optical diagnostics of lowtemperature ignition and combustion characteristics of diesel/kerosene blends under cold-start conditions. Applied Energy, 251, 113307. https://doi.org/10.1016/j.apenergy.2019.113307
Snow, S. J., Krug, J. D., Turlington, J. M. & Richards, J. E. (2023). Differential cardiopulmonary effects of isoprene-versus toluene-generated photochemically-Aged smog in rats. Atmospheric Environment, 295, 119525. https://doi.org/10.1016/j.atmosenv.2022.119525
Sun, X., Liu, C., Chen, X. & Li, J. (2017). Modeling systemic risk of crude oil imports: case of China’s global oil supply chain. Energy, 121, 449–465. https://doi.org/10.1016/j.energy.2017.01.018
Wang, X. T., J. Y. Pan, W. Li & H. P. Pan (2020). Optical experiments on diesel knock for high altitude engines under spray impingement conditions. Fuel 278, 118268. https://doi.org/10.1016/j.fuel.2020.118268
Wang, D. F., Z. J. Shi, Z. M. Yang & H. Y. Chen (2022). Numerical study on the wall-impinging diesel spray mixture formation, ignition, and combustion characteristics in the cylinder under cold-start conditions of a diesel engine. Fuel 317, 123518. https://doi.org/10.1016/j.fuel.2022.123518
Wang, X., Y. S. Ge, L. X. Yu & X. Y. Feng (2013). Comparison of combustion characteristics and brake thermal efficiency of a heavy-duty diesel engine fueled with diesel and biodiesel at high altitude. Fuel 107, 852–858. https://doi.org/10.1016/j.fuel.2013.01.060
Yang, M. Y., Gu, Y. C., Deng, K. Y. & Yang, Z. H. (2018). Analysis on altitude adaptability of turbocharging systems for a heavy-duty diesel engine. Applied Thermal Engineering 128, 1196–1207. https://doi.org/10.1016/j.applthermaleng.2017.09.065
Ye, J., & Peng, Q. (2023). Effects of porosity setting and multilayers of diesel particulate filter on the improvement of regeneration performance. Energy, 263, 126063. https://doi.org/10.1016/j.energy.2022.126063
Zhang, C. H., Li, Y., Liu, Z. T. & Liu, J. L. (2022). An investigation of the effect of plateau environment on the soot generation and oxidation in diesel engines. Energy, 253, 124086. https://doi.org/10.1016/j.energy.2022.124086
Zhu, Z. X., Zhang, F., Li, C. J. & Wu, T. (2015). Genetic algorithm optimization applied to the fuel supply parameters of diesel engines working at plateau. Applied Energy, 157,789–797. https://doi.org/10.1016/j.apenergy.2015.03.126