The influence of engine warm up phase on nitrogen oxides emission for heavy-duty Euro VI diesel engine

Abstract

Abstract. This article presents test results achieved under World Harmonized Transient Driving Cycle (WHTC) run on heavy-duty diesel engine compliant with Euro VI standard. The emission cycle was performed both for cold and hot engine start up conditions. Modal analysis of emission compounds was carried out with the focus on nitro-gen oxides (NOx) emission. The scope of the work was to assess the influence of cold start effect on selective catalytic reduction (SCR) system operation efficiency. Due to the fact that the urea injection strategy in SCR system can by activated only after certain exhaust gas temperature threshold is achieved, the NOx emission on WHTC cold start cycle is significantly greater than for the hot start one. Result analysis included also determination of time period needed for achieving the readiness of SCR system to work efficiently. The occurrence of ammonia slip emissions downstream SCR was also monitored.

Development and Research of the Adaptive Cooling System with an Electric Pump

“…Using a non-stationary ETC cycle allows obtaining good results to study of ways to modernize cooling systems for both internal combustion engines and electric transport, as well as in the papers [1][2][3][4][5][6][7][8][9][10][11][12][13][14].…”

“…Also, some studies are under way using transient cycles to assess the environmental performance of emissions [7] and non-volatile particle (PN) emissions in heavy-duty diesel vehicles (HDV) using the WHTC cycle [8], and Willems et al [9] presents an integrated power control strategy (IPC) for power and emissions for the Euro-VI diesel engine with a waste-heat recovery system (WHR) and reduced fuel consumption for trucks, which provides an additional 2.6% reduction in CO2 compared to the base strategy while meeting the NOx limit in the exhaust pipe. Sala et al [10] analyses emission compounds within WHTC with a focus on the emission of nitrogen oxides (NOx).…”

Diesel Engine 2-Stroke Breathing for Aftertreatment Warm-Up

“…11 The HD-FTP begins with the engine and aftertreatment system cold, so at the beginning of the first cycle, a high fraction of the NOx produced goes out the tailpipe. 12 A substantial fraction of the cumulative cycle tailpipe NOx can come from the first few minutes, before the SCR gets hot enough to convert effectively. Thus, getting the SCR hot as quickly as possible is critical to having low NOx emissions for the cycle as a whole, making it an essential part of the process often referred to as aftertreatment thermal management.…”

From metal-supported oxides to well-defined metal site zeolites: the next generation of passive NOxadsorbers for low-temperature control of emissions from diesel engines

“…6,8 Despite the excellent catalytic behavior and hydrothermal stability off the commercial zeolitebased SCR catalysts, they are not active enough at low exhaust temperatures, such as those occurring during the warming up of the catalytic system when the engine has been switched on. 14 This limited cold start NOx control can be explained by the negligible NOx catalytic activity at temperatures below 200°C when using Cu-or Fe-containing SCR zeolite-based catalysts (see Figure 2), and by the slow rate of urea decomposition into ammonia at low temperatures, limiting the presence of the required reducing agent to undergo the SCR of NOx. 6 Recently, it has been proposed the inclusion of a passive NOx adsorber (PNA) as a new component of the emission control system in HDD vehicles.…”