Worldwide Harmonized Light Duty Test Cycle Research Articles

Particulate matter emissions from light-duty gasoline vehicles under different ambient temperatures: Physical properties and chemical compositions

Fine particulate matter (PM2.5) from vehicle exhaust is typically emitted at breathing height and thus imposes severe adverse effects on human health and air quality. However, there is currently limited knowledge on the characteristics of PM2.5 in exhaust, specifically its chemical components, at different ambient temperatures. Particulate emissions from typical light-duty gasoline vehicles (LDGVs) were investigated on a chassis dynamometer according to the Worldwide Harmonized Light-Duty Test Cycle at ambient temperatures of 38 °C, 28 °C, 15 °C, 5 °C and − 7 °C. The results showed a significant increase in particulate mass (PM) and particle number (PN) emissions with decreasing ambient temperature, particularly during cold starts below 5 °C. The particle size distributions exhibited distinct bimodal patterns, with accumulation-mode (AM) particles (60–125 nm) dominating the gasoline direct injection (GDI) distribution and nucleation-mode (NM) particles (8–12 nm) dominating the port fuel injection (PFI) distribution. AM particles were more temperature-sensitive than NM particles. Lower temperatures produced higher emissions of elements, carbonaceous components, and large-ring polycyclic aromatic hydrocarbons, while water-soluble ions showed an opposite trend. The total toxic equivalent, primarily influenced by benzo[a]pyrene, was significantly higher at −7 °C. The penalty distribution of LDGV PM and PN, defined by comparing the emissions at the various temperatures to those at regulated temperatures (23–30 °C), exhibited notable temporal heterogeneity (winter > autumn > spring > summer) and spatial heterogeneity (northern China > southern China). These findings are essential for establishing more stringent vehicle emission standards and improving emission models in cold environments.

The Assessment of PM2.5 and PM10 Immission in Atmospheric Air in a Climate Chamber during Tests of an Electric Car on a Chassis Dynamometer

Electric cars, like internal combustion vehicles, emit particulate pollution from non-exhaust systems, i.e., tires and brakes, which is included in the Euro 7 emission standard planned for implementation. Tests conducted on chassis dynamometers are accompanied by particulate emissions from non-exhaust systems, which are introduced into the ambient air on the test bench. Particulate emissions tests from non-engine systems on chassis dynamometers are mainly aimed at measuring the mass or number of particulates from tires and brakes. In contrast, little attention is paid to the immission of particulate matter from tires and brakes on the dynamometer during tests, which in the case of electric cars include, for example, measurements of energy consumption or range. Therefore, in order to draw attention to the problem of these emissions, the authors carried out measurements of PM2.5 and PM10 immissions into the air in the climatic chamber during tests of an electric car on a chassis dynamometer. The car tests were carried out in accordance with the WLTC (Worldwide harmonized Light duty Test Cycle) and at constant speed. Based on the test results, a model was proposed for the immission of particulate matter in laboratory air from tire and brake abrasion, taking traffic parameters into account. The results and the developed model show that air quality, in terms of particulate content, deteriorates significantly during testing.

A methodology to develop multi-physics dynamic fuel cell system models validated with vehicle realistic drive cycle data

Fuel cell (FC) technology has been identified as a technically attractive solution to decarbonize the transportation sector, especially for heavy-duty vehicles. In this context, the industry and the scientific community are in need of advanced fuel cell systems (FCS) models that are able to replicate real-world operating conditions. Due to the scarcity of said models in the open literature, this study aimed to develop a comprehensive methodology to calibrate and validate multi-physics dynamic FCS models. Therefore, the key contribution of this paper is the detailed description of the calibration process for each component and the calibration order. The specific focus here was to accurately describe the behavior of the FC stack as well as the cathode, anode, and cooling circuits of the balance of plant. The model was calibrated with the aid of experimental data from a Toyota Mirai FC electric vehicle, which was predominantly retrieved from the vehicle’s Controller Area Network (CAN) bus system thereby negating the need for major intrusion into the powertrain system. The validation process was deemed successful with the model being able to truthfully replicate the characteristics of the FC vehicle operated on the World-wide harmonized Light duty Test Cycle (WLTC) 3b and US06 driving cycle. The time-resolved physical parameters such as the cathode pressure, mass flow, or the FC stack temperature were captured with high fidelity, while the overall performance parameters such as the H2 consumption in the stack and the system, and the compressor energy consumption were predicted accurately with a deviation lower than 0.47%, 1.75% and 1.89% with respect to the experimental data, respectively.

Experimental Validation of a Permanent Magnets Magnetorheological Device under a Standardized Worldwide Harmonized Light-Duty Test Cycle

In this paper, the experimental validation of an innovative clutch based on magnetorheological fluids (MRFs) excited by permanent magnets is described. The device, used in automotive applications to engage and disengage the vacuum pump, is tested using a standardized Worldwide harmonized Light-duty Test Cycle (WLTC). A test bench is built, and the system is observed in its operation for one hour, considering two consecutive WLTCs. The temperature increase slightly impacts the clutch’s behavior; in particular, the on-state performance of the device, mainly determined by the magnetic field-induced torque, remains largely unaffected by the temperature increase. The results showed that the performance of the proposed MRF-based device is only marginally affected by the phenomena that take place during the actual operation (e.g., temperature increase, shaft slip), confirming the effectiveness of the design.

Emission Reduction from a Light-Duty Diesel Vehicle over Two Driving Cycles through Dynamic Correction Calibration.

The potential of a method of transient control of model-based engine charge control (MCCT) is investigated to minimize nitrogen oxide (NOx) emissions of a light-duty diesel vehicle over two driving cycles, the worldwide harmonized light-duty test cycle (WLTC) and real driving emission (RDE) cycle. The MCCT function was switched on by calibrating factor maps corrected for several parameters. In addition, the relationship between electronic control unit signals and nitrogen oxide (NOx) emissions was analyzed under the WLTC and RDE. The engine-out and tail-pipe NOx emissions in the WLTC and RDE could achieve varying degrees of reduction with MCCT.

Research on Multifractal Characteristics of Vehicle Driving Cycles

Vehicle driving cycles have complex characteristics, but there are few publicly reported methods for their quantitative characterization. This paper innovatively investigates their multifractal characteristics using the fractal theory to characterize their complex properties, laying the foundation for applications such as vehicle driving cycle feature identification, vehicle energy management strategies (EMS), and so on. To explore the scale-invariance of the vehicle driving cycles, the four vehicle driving cycles were analyzed using the Multifractal Detrended Fluctuation Analysis (MF-DFA) method, three of which are standard vehicle test cycles: the New European Driving Cycle (NEDC), the World-wide harmonized Light-duty Test Cycle (WLTC) and the China Light-duty Vehicle Test Cycle for Passenger Car (CLTC-P), and the other is the Urban Road Real Driving Cycle (URRDC), which was obtained by analyzing and processing vehicle driving data collected in actual urban driving conditions. The fluctuation functions, the generalized Hurst exponents, the mass exponent spectra, the multifractal singularity spectra, and the multifractal characteristic parameters were calculated to verify the multifractal characteristics, and to quantify the fluctuation singularities of different driving cycles as the time series. The results show that the fluctuations of all four driving cycles have long-range anticorrelations and exhibit significant multifractal characteristics. The results can provide a basis for the analysis of the complexity of the vehicle driving cycles.

Hydrogenated terpenic renewable fuels: Emissions and combustion analysis

Waste terpenes from paper industry, pine resin tapping or citric industry are abundant feedstocks that can be used as components in diesel blends. However, terpenes such as turpentine or orange oil are highly reactive, tend to form deposits and show high sooting tendency. These drawbacks can be solved with hydrogenation, which reduces the degree of unsaturation of the molecule and thus, the formation of soot. In this work, blends at 20 vol % of hydrogenated turpentine and hydrogenated orange oil in diesel fuel were tested in a Euro 6 diesel engine following Worldwide harmonized Light-duty Test Cycle (WLTC). Engine performance, gaseous and particle matter emissions and combustion analysis from these blends were compared with those from diesel fuel. Engine performance was similar for all fuels, with slight differences in equivalence ratio and exhaust gas recirculation (EGR) rate. CO and HC emissions were increased whereas NOx emissions remained constant when blends were tested, with respect to diesel. Sooting tendency was improved since particle mass emissions were reduced despite the particle number emissions were similar to those from diesel. Combustion was quite similar between all fuels and only ignition delay was longer and combustion velocity higher for blends in comparison with diesel.

Modeling and Simulation of Extended-Range Electric Vehicle with Control Strategy to Assess Fuel Consumption and CO2 Emission for the Expected Driving Range

Extended-Range Electric Vehicles (EREVs) are intended to improve the range of battery electric vehicles and thus eliminate drivers’ concerns about running out of energy before reaching the desired destination. This paper gives an insight into EREV’s performance operating according to the proposed control strategy over various driving cycles, including the Worldwide Harmonized Light-duty Test Cycle Class 3b (WLTC 3b), Federal Test Procedure (FTP-75), and China Light-Duty Vehicle Test Cycle (CLTC-P). Simulation runs were performed in Matlab-Simulink® for different cases of drive range, electricity mix, and vehicle mass. The control strategy goal was to aim at a specified value of battery state of charge at the targeted range value. The obtained test results included: pure electric drive range, acceleration times, EREV range tests, control strategy range errors, Range Extender (REX) utilization metric and distribution of its engagement instances, fuel consumption, total equivalent CO2 emission, powertrain efficiency, and specific energy consumption. The control strategy operated on average with a range error of −1.04% and a range mean square error of 2.13%. Fuel consumption (in range extension mode) varied between 1.37 dm3/100 km (FTP-75) and 6.85 dm3/100 km (WLTC 3b Extra-High 3). CO2eq emission was 95.3–244.2 g/km for Poland, 31.0–160.5 g/km for EU-27, and 1.2–147.6 g/km for Sweden. This paper is a valuable source of information for scientists and engineers seeking to learn the advantages and shortcomings of EREV drives with a proposed control strategy, based on various sets of results.

Driving Cycles for Estimating Vehicle Emission Levels and Energy Consumption

Standard driving cycles (DCs) and real driving emissions (RDE) legislation developed by the European Commission contains significant gaps with regard to quantifying local area vehicle emission levels and fuel consumption (FC). The aim of this paper was to review local DCs for estimating emission levels and FC under laboratory and real-world conditions. This review article has three sections. First, the detailed steps and methodologies applied during the development of these DCs are examined to highlight weaknesses. Next, a comparison is presented of various recent local DCs using the Worldwide Harmonized Light-Duty Test Cycle (WLTC) and FTP75 (Federal Test Procedure) in terms of the main characteristic parameters. Finally, the gap between RDE with laboratory-based and real-world emissions is discussed. The use of a large sample of real data to develop a typical DC for the local area could better reflect vehicle driving patterns on actual roads and offer a better estimation of emissions and consumed energy. The main issue found with most of the local DCs reviewed was a small data sample collected from a small number of vehicles during a short period of time, the lack of separate phases for driving conditions, and the shifting strategy adopted with the chassis dynamometer. On-road emissions measured by the portable emissions measurement system (PEMS) were higher than the laboratory-based measurements. Driving situation outside the boundary conditions of RDE shows higher emissions due to cold temperatures, road grade, similar shares of route, drivers’ dynamic driving conditions, and uncertainty within the PEMS and RDE analysis tools.

Twin‐model framework development for a comprehensive battery lifetime prediction validated with a realistic driving profile

AbstractLithium‐ion technologies have become the most attractive and selected choice for battery electric vehicles. However, the understanding of battery aging is still a complex and nonlinear experience which is critical to the modeling methodologies. In this work, a comprehensive lifetime modeling twin framework following semi‐empirical methodology has been developed to predict the crucial degradation outputs accurately in terms of capacity fade and resistance increase. The constructed model considers all the relevant aging influential factors for commercial nickel manganese cobalt (NMC) Li‐ion cells based on long‐term laboratory‐level investigation and combines both the cycle life and the calendar life aspects. To demonstrate robustness, the model is validated with a real‐life worldwide harmonized light‐duty test cycle (WLTC). The model can precisely predict the capacity fade and the internal resistance growth with a root‐mean‐squared error (RMSE) of 1.31% and 0.56%, respectively. The developed model can be used as an advanced online tool forecasting the lifetime based on dynamic profiles.

Primary organic gas emissions from gasoline vehicles in China: Factors, composition and trends

Continuous tightening emission standards (ESs) facilitate the reduction of organic gas emissions from gasoline vehicles. Correspondingly, it is essential to update the emissions and chemical speciation of total organic gases (TOGs), including volatile organic compounds (VOCs), intermediate volatility organic compounds (IVOCs), CH4, and unidentified non-methane hydrocarbons (NMHCs) for assessing the formation of ozone and secondary organic aerosol (SOA). In this study, TOG and speciation emissions from 12 in-use light-duty gasoline vehicle (LDGV) exhausts, covering the ESs from China II to China V, were investigated on a chassis dynamometer under the Worldwide Harmonized Light-duty Test Cycle (WLTC) in China. The results showed that the most effectively controlled subgroup in TOG emissions from LDGVs was VOCs, followed by the unidentified NMHCs and IVOCs. The mass fraction of VOCs in TOGs also reduced from 61 ± 9% to 46 ± 18% while the IVOCs gently increased from 2 ± 0.4% to 8 ± 4% along with the more stringent ESs. For the VOC subsets, the removal efficiency of oxygenated VOCs (OVOCs) was lower than those of other VOC subsets in the ESs from China IV to V, suggesting the importance of OVOC emission controls for relatively new LDGVs. The IVOC emissions were mainly subject to the ESs, then driving cycles and fuel use. The formation potentials of ozone and SOA from LDGVs decreased separately 96% and 90% along with the restricted ESs from China II-III to China IV. The major contributor of SOA formation transformed from aromatics in the VOC subsets for China II-III vehicles to IVOCs for China IV/V vehicles, highlighting that IVOC emissions from LDGVs are also needed more attentions to control in future.

Structure majorization on the surface of microporous layer in polymer electrolyte membrane fuel cells to optimize performance and durability

Proton exchange membrane fuel cell (PEMFC) is regarded as a potential future power source for automotive applications. Microporous layer (MPL) enhances the output performance and durability of PEMFCs by regulating water management. In this study, the structure majorization on the surface of MPL is investigated for the first time. Polymethyl Methacrylate (PMMA), a kind of pore agent that can form specific size and regular shape, is used in this paper to create the special structure. Worldwide Harmonized Light-duty Test Cycle (WLTC) operating condition is used in durability tests, which is in line with the actual application conditions of PEMFC. The sample with smaller PMMA (MPL-S) exhibits predominant performance, maximum power density reaching 1.30 W/cm2 under the humidification of 100%RH (relative humidity). After online durability test, MPL-S best maintains its performance. The maximum power density of MPL-S only drops by 10.6% after 100 h durability test. Results can prove that water is uniformly guided into the structure and then discharged, not hindering the contact between the gas and active sites of the catalyst. The mass transfer resistance is reduced and the drainage capacity is improved. The majorization is instructive for water management research on MPL in PEMFCs and the durability under WLTC operating condition can be used as a reference for practical applications.

Battery cycle life study through relaxation and forecasting the lifetime via machine learning

Battery lifetime modeling and prediction of precise capacity degradation for real-life applications are critical to understanding the complex and non-linear battery behavior. However, the application of accurate and robust aging models on dynamic on-road scenarios is still a challenge. In this work, a comprehensive aging dataset of 40 Nickel Manganese Cobalt (NMC) cells is generated for two years considering distinct relaxation phases in the function of the state of charge (SoC), temperature, and time. A qualitative analysis of the diversified aging parameters along with the sensitivity analysis of the rest criteria is conducted. Taking the discharge capacity as the pivotal predictor, a robust training dataset is built and preliminary fed to common data-driven models. Among them, the Gaussian process regression (GPR) is identified to be the best suit with which a 0.02% root-mean-squared error (RMSE) can be achieved for battery life prediction when tested with a static profile choosing an exponential kernel. Further, to demonstrate a real-life scenario, a worldwide harmonized light-duty test cycle (WLTC) is performed, and the capacity fade percentile can be predicted accurately with a 0.05% RMSE. This research shows that data-driven algorithms like GPR can be a promising online tool that can forecast the entire lifetime with high precision for dynamic profiles.

Particulate emissions from direct-injection and combined-injection vehicles fueled with gasoline/ethanol match-blends – Effects of ethanol and aromatic compositions

Gasoline direct injection (GDI) vehicles are up against the great challenge of particulate emissions, which were mandatorily constrained by the China-6 emission standard. Given the worldwide fuel transition from gasoline to gasoline/ethanol blends, it is important to discuss the effects of ethanol and aromatic contents on particulate emissions of GDI vehicles. In this work, 10% volume of ethanol was added into China-6b gasoline replacing C8 (carbon atoms = 8) alkanes (E10), and the specific aromatic compounds in E10 fuels were adjusted under holding total aromatic content. As there was no limit on individual aromatic compounds in the gasoline standard, the effects of aromatic compounds were investigated over the worldwide harmonized light-duty test cycle (WLTC) with engine cold-start and hot-start at room and low temperatures. For GDI vehicles, the results showed that ethanol substituting part of C8 alkanes in gasoline increased the particulate number (PN) but decreased particulate mass (PM) emissions. For vehicles using the combined port fuel injection (PFI)/GDI injection systems, the PM and PN emissions climbed. Aromatic compositions significantly impacted the particulate emissions. With the concentrations of heavy aromatics increased, PM and PN emissions of both GDI and combined-injection vehicles were shown to multiply.

WLTC and real-driving emissions for an autochthonous biofuel from wine-industry waste

Residues from the wine industry constitute an abundant feedstock for biodiesel production in wine-producing countries. The use of grapeseed oil, together with bioethanol obtained from distillation of wine surplus or grape skins and stalks and wine lees, as reagents in the transesterification reaction, results in a mixture of fatty acid ethyl esters (FAEE), which is a fully renewable, autochthonous, and waste-derived biofuel. In this work, a blend of FAEE produced from grape seed oil with diesel fuel was selected based on a study of fuel properties, and the optimal blend, with 30% v/v of FAEE, was tested in a Euro 6 engine following the Worldwide harmonized Light-duty Test Cycle (WLTC) and a Real Driving Emissions Cycle (RDE), as required in the new certification procedures. Engine performance and emissions from this blend and a commercial diesel fuel were compared. The FAEE blend showed a significant potential to reduce particle emissions, both in mass and number (from 23% in number to 46.5% in mass for WLTC, and from 56% in number to 61% in mass for RDE), and CO (25.5% for WLTC and 39% for RDE) but penalized NOx (32% higher in WLTC and 26.4% higher in RDE).

Impacts of the New Worldwide Light-Duty Test Procedure on Technology Effectiveness and China's Passenger Vehicle Fuel Consumption Regulations.

As a main measure to promote the development of China’s energy–saving and new energy vehicles, the Phase V fuel consumption regulation is dramatically different from the past four phases, especially in the test procedure, moving from the New European Driving Cycle (NEDC) to the worldwide harmonized light duty test cycle (WLTC) and corresponding test procedure (WLTP). The switch of test procedure will not only affect the effectiveness of technologies but also change the fuel consumption target of the industry. However, few studies have systematically investigated the impacts of the new WLTP on the Chinese market. This study establishes a “technology–vehicle–fleet” bottom–up framework to estimate the impacts of test procedure switching on technology effectiveness and regulation stringency. The results show that due to the WLTP being closer to the real driving condition and more stringent, almost all baseline vehicles in the WLTP have higher fuel consumption than that in the NEDC, and diesel vehicles are slightly more impacted than gasoline vehicles. In addition, the impacts are increased with the strengthening of electrification, where the fuel consumption of plug–in hybrid electric vehicles (PHEVs) and range-extended electric vehicles (REEVs) in the WLTP are about 6% higher than that in the NEDC. Engine technologies that gain higher effects in low load conditions, such as turbocharging and downsizing, fuel stratified injection (FSI), lean–burn, and variable valve timing (VVT), are faced with deterioration in the WLTP. Among these, the effect of turbocharging and downsizing shows a maximum decline of 8.5%. The variable compression ratio (VCR) and stoichiometric gasoline direct injection (SGDI) are among the few technologies that benefited from procedure switching, with an average improvement of 1.6% and 0.2% respectively. Except for multi–speed transmissions, which have improvement effects in the WLTP, all automatic transmissions are faced with decreases. From the perspective of the whole fleet and national regulation target, the average fuel consumption in the WLTP will increase by about 7.5% in 2025 compared to 4 L/100 km in the NEDC. According to the current planning of the Chinese government, the fuel consumption target of Phase V is set at 4.6 L/100 km in 2025, which is equivalent to loosening the stringency by 0.3 L/100 km. In Phase VI, the target of 3.2 L/100 km is maintained, which is 30.4% stricter than that of Phase V, and the annual compound tightening rate reaches 7.5%. This means that automakers need to launch their product planning as soon as possible and expand the technology bandwidth to comply with the Phase VI fuel consumption regulation, and the government should evaluate the technical feasibility before determining the evaluation methods and targets of the next phase.

Immersion temperature effects on light-duty gasoline vehicles’ fuel consumption under world-wide harmonized light-duty test cycle (WLTC)

Basing on the experimental study of fuel consumbtion in World-wide Harmonized Light-duty Test Cycle (WLTC ), this paper conducted the effects of using different immersion temperature on the fuel consumption of a light-duty gasoline vehicle. The study mainly studied the first phase of WLTC with three gaseous pollutant emissions: carbon dioxide, carbon monoxide and unburned hydrocarbon(CO2, CO and HC )which is measured to caculate the fuel consumption of Light-duty Gasoline Vehicles. It appears that with the increase of time the working condition of the vehicle tends to be stable resulting in the similar emission of the gaseous pollutant in the different test. Which means the immersion temperature mainly effects gaseous pollutant emissions in low-speed phase in WLTC. Besides, the cold start of engine had generated a large quantity of carbon monoxide and unburned hydrocarbon, but it is different for the carbon dioxide which was generated continuously in the first whole phase. The study also found that the use of a higher immersion temperatures (26℃) is more favorable than a lower immersion temperatures (23℃) in the typy of testing vehicle’s fuel consumption in the WLTC test cycle.

Influence of Test Cycles on Energy Consumption Test of Electric Vehicles

In order to verify the necessity of the application of China Automotive Test Cycle which is constructed through actual driving data in china of more than 55 million kilometers in the energy consumption test of electric vehicles in China, this paper compares the characteristics of New European Test Cycle (NEDC), World-wide harmonized Light duty Test Cycle (WLTC) and China light-duty vehicle test cycle for passenger car(CLTC-P), and analyzes the differences of vehicle energy demand under different test cycles from theoretical and simulation point, simulation results show that the endurance mileage is longest and the energy recovery strategy is more effective under CLTC-P cycle. Finally, four types of vehicles are selected to carry out the endurance mileage test under these three test cycles. The test results are consistent with the simulation results. Therefore, in order to make the test results of electric vehicle energy consumption closer to the actual use of our country, CLTC-P should be selected to replace NEDC and WLTC cycle.

Experimental study on the energy consumption of gasoline engine lubricating pumps in standardized driving cycles

This paper aims to evaluate the potential of lubricating pumps to reduce the fuel consumption of passenger cars under the standardized driving cycles conditions. The transient parameters of lubricating pump in a gasoline engine are measured based on the test bench, and a quasi-steady-state model is brought forward to calculate the matching work state of lubricating pump and engine lubricating system. The result shows that a certain amount of excessive hydraulic power is needed under low speed condition to meet the step increase of lubricating requirement. In the range over piston spray cooling speed, the excessive hydraulic power of lubricating system is proportional to engine speed, and this part of driving power can be saved. The duration of acceleration conditions in driving cycles and the lubricant temperature are the most critical factors affecting the lubricating pump’s driving power. At 100 °C, the lunricating system driving energy costed in the Urban Driving Cycle (UDC) is 60.2% lower than 25 °C, but it is 42.1% in the World-wide harmonized Light duty Test Cycle (WLTC) due to the increase of acceleration condition. With a fully variable lubrication pump, the driving energy levels can reduce by 5.76%, 8.96%, 32.1% in WLTC, Extra-Urban Driving Cycle (EUDC), and UDC, respectively.

Numerical research on the performance, combustion and energy flow characteristics of gasoline-powered vehicle under WLTC

In order to evaluate and improve the performance of a vehicle equipped with a gasoline engine, an integrated model of the vehicle coupling with a detailed engine model was established to investigate the performance, combustion and energy distribution under the Worldwide Harmonized Light duty Test Cycle (WLTC) of cold start. The results show that 2.3–3.2 kW of brake power is required for the automatic transmission under idling conditions. Brake thermal efficiency mainly ranges from 17.71% to 31.94% apart from the rapid deceleration conditions and exhibits poor fuel economy under low-speed phase. Combustion phase of 50% mass fraction burnt (CA50) is usually delayed in case of knocking combustion under higher speed conditions. Moreover, it is delayed to 65 °CA at the initial stage of cold start for fast light-off of three-way catalyst (TWC), but 10–90% combustion duration (CA10-90) is not very sensitive to the cold start. The heat cumulated in the engine structure is obvious at the initial stage and up to 37.39% but finally occupies 4.93%. The proportion of heat transfer loss to coolant increases after 300 s and finally occupies 22.71%. Exhaust gas loss mainly ranges from 0.91 kW to 28.42 kW and its proportion first decreases and then increases to 26.46%. After 1160 s, it exhibits higher growth rate. Pumping loss varies from 0.1 kW to 2.67 kW and occupies 2.2% in the total energy. Furthermore, the findings in the paper can be applied to evaluate and optimize the energy distribution by changing different technologies or strategies in the future.