Fuel Injection Timing Research Articles

Characterisation of emission-performance paradigm of a reactivity-controlled compression ignition engine using artificial intelligent based multi-objective response surface methodology model fuelled with ternary fuel

Petroleum reserves all over the world have been severe to the point of depletion in the previous several decades. Modern transportation and industry employ diesel-fuelled engines because of their higher thermal efficiency. This study investigates the reactivity-controlled compression ignition engine characteristics utilising n-octanol and Moringa oleifera oil blended with diesel. Tests are carried out at maximum load with different bowl geometries to examine the influence of operating parameters, namely injection pressure (500–1000 bar) and static injection timing (23–27°bTDC). Box–Behnken Forecasting input variables like injection pressure and timing with different piston bowls is done using the response surface approach. Maximum brake thermal efficiency and brake power are achieved with this ideal model, and the emission of unburned HC and NO x is decreased. The effects of several variables, including piston bowls, fuel injection timing (FIT) and fuel injection pressure, are examined for an reactivity-controlled compression ignition engine running on Moringa oleifera oil/1-octanol fuel using an L27 orthogonal array. Various models were created and verified using experiment findings as the basis.

Experimental investigations on impact of exhaust gas recirculation in CI engine using jute biodiesel

Biodiesel can be used in place of diesel. Biodiesels produce less HC; they are renewable, less toxic, and biodegradable. There are certain drawbacks to the use of biodiesel, like low performance and high NOx. There is a need to search for a technology that decreases emissions and increases performance. Exhaust Gas Recirculation (EGR) is the optimal solution. Investigations were executed on a diesel engine installed with an exhaust gas recirculator and fuelled with jute biodiesel and assessed for 5%, 10%, and 15% EGR along with variations in fuel injection timing of 27 bTDC and 29 bTDC. The results of these conditions were compared with that of diesel and analysed. The heat release rate for 27 bTDC injection timing has increased by 6 kJ, and for 29 bTDC injection timing, it has increased by 5 kJ for 5%, 10%, and 15% EGR valve openings.

Effect of fuel injection timing on performance and emissions with a dedicated direct injector in a hydrogen engine

In this study, hydrogen fuel was injected directly into a cylinder using a prototype of a dedicated hydrogen direct injector (HDI). The effects of fuel injection timing and amount of hydrogen fuel injected on engine output performance and emissions (e.g., nitrogen oxides and carbon dioxide) were investigated by varying the fuel injection timing from before top dead center (BTDC) 190 crank angle degree (CAD) toward BTDC 60 CAD. Strategies for maximizing the engine’s output performance when an after-treatment system for nitrogen oxide removal catalysts is not used were assessed. When using the HDI, a torque improvement result (up to 35.9%) can be obtained even under the condition that the hydrogen supply pressure was half as low as compared to the case of using a gasoline direct injector for hydrogen fuel. Under the condition of retarded fuel injection timing, a locally rich mixture is formed to increase the emission of nitrogen oxides at a level of 50 ppm or higher. The engine oil is burned to affect the emission of carbon dioxide (CO2), which is proportional to the load.

Development of a Zero-Dimensional Model for a Low-Speed Two-Stroke Marine Diesel Engine with Exhaust Gas Bypass and Performance Evaluation

Most large commercial vessels are propelled by low-speed two-stroke diesel engines due to their fuel economy and reliability. With increasing international concern about emissions and the rise in oil prices, improvements in engine efficiency are urgently needed. In the present work, a zero-dimensional model for a low-speed two-stroke diesel engine is developed that considers the exhaust gas bypass and geometry structures for the gas exchange model. The model was applied to a low-speed two-stroke 7G80 ME-C9 marine diesel engine and validated with engine shop test data, which consisted of the main engine performance parameters and cylinder pressure diagrams at different loads. The simulation results were in good agreement with the experimental data. Thus, the model has the ability to predict engine performance with good accuracy. After model validation, the variations in compression ratio, fuel injection timing, exhaust gas bypass valve opening portion, exhaust valve opening timing, and exhaust valve closing timing effects on engine performance were tested. Finally, the influence level of different parameters on engine performance was summarized, which can be used as a reference to determine the reasons for high fuel consumption in some cases. The developed engine performance model is considerable in digital twins for performance simulation, health management, and optimization.

Parametric optimization with Biodiesel-water emulsion under premixed lean combustion to achieve high efficiency and clean combustion

Advanced low temperature combustion (LTC) aids in simultaneously controlling exhaust emissions of oxides of nitrogen (NOx) and particulate matter (PM). However, LTC strategies are constrained by achievable load range restriction and higher levels of unburned hydrocarbon (HC) and carbon monoxide (CO). The present investigation envisages combining renewable biodiesel-water emulsions and an advanced premixed lean combustion strategy to curtail the higher HC and CO emissions without sacrificing engine performance. Non-edible Karanja oil was the source of biodiesel and the emulsion stabilizer. A production light-duty diesel engine is modified to run under premixed lean combustion conditions based on late injection using a fully-flexible electronic fuel injection system. The engine operating parameters were optimized, including fuel injection timing, EGR flow rate, and emulsion water concentration. Emulsions of neat biodiesel were prepared to contain 6, 12, and 18% water on a mass basis using 1 and 2% surfactant by mass. The fuel injection timing was varied from 2 to 4 degrees after the top dead centre, and up to 15% EGR flow rate was utilized. Design of experiments aided in minimizing the number of engine tests. The performance and emission parameters were the output responses. Taguchi Grey Relational Analysis established the optimal combination of input factors to improve engine performance and reduce exhaust emissions. Engine experiments at optimized operating conditions revealed that compared to conventional diesel combustion, the brake thermal efficiency and brake specific fuel consumption improved by 33 and 16%, respectively, at 5.08 bar BMEP. The NOx, smoke and HC emissions were reduced by 68, 73 and 46%, while CO emissions increased nearly two-fold.

Experimental Evaluation of Pilot and Main Injection Strategies on Gasoline Compression Ignition Engine—Part 1: Combustion Characteristics

<div>Climate change and stringent emission regulations have become major challenges for the automotive sector, prompting researchers to investigate advanced combustion technologies. Gasoline compression ignition (GCI) technology has emerged as a potential solution, delivering higher brake thermal efficiency with ultra-low nitrogen oxides (NOx) and particulate emissions. Combustion stability and controls are some of the significant challenges associated with GCI. This study investigates the combustion characteristics of a two-cylinder diesel engine in GCI mode. GCI experiments were performed using a low-octane fuel prepared by blending 80% (v/v) gasoline and 20% (v/v) diesel (G80). Baseline experiments were conducted in conventional diesel combustion (CDC) mode. These experiments investigated the effects of double pilot injection, first pilot fuel ratio, and the start of main fuel injection timing (10–8°CA before top dead center, bTDC). The results indicated that the GCI mode produced significantly lower (~10%) in-cylinder pressure than the CDC mode. Higher pilot fuel proportions exhibited a lower heat release rate (HRR) at low loads. Retarded main injection showed a lower heat release in the premixed combustion phase than the advanced main injection case at all loads. In addition, retarded main injection timing showed retarded start of combustion (SoC) and end of combustion (EoC). GCI mode exhibited higher cyclic variations than baseline CDC mode, which need to be addressed.</div>

Collective influence and optimization of 1-hexanol, fuel injection timing, and EGR to control toxic emissions from a light-duty agricultural diesel engine fueled with diesel/waste cooking oil methyl ester blends

This study attempts to utilize a ternary blend comprising diesel, biodiesel, and 1-hexanol in a direct injection (DI) diesel engine. A response surface methodology (RSM) based optimization with the full factorial experimental design was used to optimize the fuel injection timing and exhaust gas recirculation (EGR) with an objective to maximize the performance of the engine with minimum emissions. Three injection timings and three EGR rates were used. Multiple regression models developed using RSM for the responses were found to be statistically significant. Interactive effects between injection timing and EGR on responses for the blends were studied. From a desirability approach, a HX20 blend (diesel 50 v/v% + biodiesel 30 v/v% + 1-hexanol 20 v/v%) injected at lesser fuel injection timing and EGR rate delivered optimum emission and performance characteristics. Confirmatory tests validated the models to be adequate. With reference to diesel, at optimum conditions, there was a significant reduction in nitrogen oxides (NOx) emission with a marginal increase in smoke, hydrocarbon (HC) and carbon monoxide (CO) emissions. Also, it was found that there was minimal loss in brake thermal efficiency (BTE) of the engine. With respect to waste cooking oil methyl ester operation, the blend reduced nitrogen oxides (NOx), smoke, carbon monoxide (CO) and hydrocarbon (HC) emissions significantly with marginal loss in BTE.

RSM approach for optimising engine operating parameters of VCR engine fuelled with Xanthium strumarium L. seed oil biodiesel blends

With the depletion of fossil fuels, the demands for fuel prices led by OPEC are increasing so possible fuel power for the current-day diesel engine is the need of today. Biodiesel is a significant alternative fuel; however, engine parameters need to be optimised on the basis of best performance and least exhaust discharges. In this work, experimentation was carried out fuelling blends of Xanthium strumarium L. seed oil biodiesel with diesel in volumetric proportions of 10%, 20% and 30% on a VCR diesel engine under engine fluctuations of engine’s volumetric ratio, fuel injection pressure and the start of fuel injection timing. Response surface methodology was employed and modelled output responses of the engine were quadratic and observed to be statistically fit with good confidence levels. Based on the RSM optimiser, the predictions made were marked as IT 24.57580bTDC, IP-180 bar, CR-16.5657 and blend levels 29.1919%v/v with a composite desirability score of 0.6824.

Performance optimization of RCCI engines running on landfill gas, propane and hydrogen through the deep neural network and genetic algorithm

The present study is to optimize the performance of the reactivity controlled compression ignition engines taking landfill gas plus propane or hydrogen or a combination of both as low reactivity fuels. A heavy duty, 2.44 L caterpillar 3401E single-cylinder diesel engine is employed for the numerical simulation, and a number of the most effective variables on the engine performance are determined as inputs. The research purposes are to procure the maximum energy efficiency (i.e. the maximum thermodynamics first and second law efficiencies, and the minimum indicated specific fuel consumption), and to fulfill the Euro VI engine emissions standards (i.e. CO, UHC, and NOX maximum emissions 1.5, 0.13, and 0.4 gr/kW-hr, respectively). The maximum peak pressure and peak pressure rise rate are restricted to 150 bar and 10 bar/crank angle deg., respectively. The deep neural networks are utilized to obtain the engine mathematical model and the genetic algorithms are used to attain the intended optimization. Based on the outcomes, injecting a combination of propane and hydrogen to the premixed charge by 3.4 and 6.6 % by volume, respectively, and adopting an engine equivalence ratio of 0.31, an intake pressure of 1.983 bar, and a diesel fuel injection timing of about 75 deg. before the top dead center provide the maximum performance for the considered engine. In the optimized state, a 6.6 % hydrogen by volume takes 2.5 % of the total fuels energy. This research has proven that numerical modeling in combination with deep neural networks and genetic algorithms is an effective methodology to optimize the performance of the reactivity controlled compression ignition engines. Moreover, a dimensional analysis made shows the dimensionless peak pressure is function of the dimensionless engine heat release and the ratio of the engine cumulative heat release to the primary inlet mixture flow work. In the optimized case, the dimensionless ratio of cumulative heat release to the inlet flow work of fluid is 11.5.

Control-Oriented Combustion Modeling for Compression-Ignition Engines Operating With Low Cetane Fuels

To support the transition toward sustainable alternative fuels in the transportation sector, advanced statistical modeling techniques are needed to characterize and control combustion at low cetane fueling conditions. In this work, a novel control-oriented combustion phasing model is presented that simulates asymmetrical phasing distributions as a function of fuel cetane, fuel injection timing, and electrical power supplied to a thermal ignition assist device. The model was regressed using experimental data from a commercial compression-ignition (CI) engine operating with four fuel blends of cetane number ranging from 25 to 48. The model estimates the mode and median of phasing distributions within 2.4 and 2.6 crank angle degrees (CAD), respectively, over a range of 52 CAD. Additionally, kernel density estimation (KDE) is proposed for nonparametric modeling of torque as a function of phasing. A set of KDE-driven extremum seeking algorithms for learning torque-optimal phasing ranges and probabilistic misfire limits is validated across the multi-fuel data. By using a probabilistic criteria, this approach can permit an acceptable proportion of undesired events to occur before classifying a limit. This feature better suits it for engine operation with low cetane fuels, where late burns and misfires may not be entirely avoidable. This work will facilitate online learning-based control strategies that can enable CI engines to adapt to fuels with a wide range of ignition behaviors.

Effect of Fuel Injection Timing on Marine Diesel Engine Blended with Isoamyl Alcohol

In order to study the problem that the pressure in the cylinder decreases significantly after diesel is mixed with isopentanol, which leads to the reduction of power performance, the software of AVL-FIRE is used for simulation, and the angle of start injection is adjusted to improve cylinder pressure. It turns out that in terms of combustion, The maximum burst pressure is reduced after mixing isoamyl alcohol. By increasing fuel injection timing, maximum burst pressure can rise to 87.8%-94.5% of the original engine respectively. The indicated power can be increased to 91.92%-95.62% of the original. In terms of emissions, after mixing, with the increase of fuel injection timing, NO does not change significantly, Soot shows a downward trend.

Study on Combustion and Emission Performance of Dual Injection Strategy for Ammonia/Hydrogen Dual-Fuel Engine

To realize zero carbon emission in internal combustion engines and boost the growth of ammonia fuel, we mixed a few hydrogens into ammonia fuel to boost the atomization and combustion performance in the combustion chamber. We study hydrogen and ammonia mixed and injected directly through two injectors, the intake temperature is 551k, to find the best injection advance angle combination to ensure the overall working performance of the ammonia Dual fuel engine. The investigation shows that when the main/auxiliary fuel injection timing is 704°CA, the knock value is less than 2, the combustion in the cylinder is gentle, and the negative work phenomenon of knock combustion is avoided. The engine power is the highest and the best economy. The emissions of soot, CO, HC, and CH2O are at a very low level, the CO2 content before and after combustion increases to zero, and the NOx emission is slightly higher than the original engine. We will improve engine NOx emission through SCR Technology in the future. The investigation results will boost the development of an ammonia and hydrogen compression ignition engine and boost the internal combustion engine to zero carbon combustion mode.

Static fuel injection timing’s effect on emissions of madhuca indica bio-diesel mixtures as fuel to operate direct injection diesel engine

The CIDI engine parameters of Madhuca indica bio-diesel and its various mixtures with conventional fuel is demonstrated. A four-stroke conventional CI engine tests are conducted with various static fuel injection timings (SITs) of 22°, 23° and 24° bTDC with 220 bar standard NOP at full load. From the present experimental outcomes, it is found that 22° bTDC for base fuel (B-0) and 50% of base fuel and 50% of bio-diesel (B-50) fuel give lower HC, CO, smoke density and NOx.

Optimization of fuel injection timing and ignition timing of hydrogen fueled SI engine based on DOE-MPGA

For the port injection hydrogen-fueled spark ignition (SI) engine modified from the Jialing JH600 gasoline engine, the hydrogen injection timing and ignition timing of the hydrogen SI engine are comprehensively optimized on the AVL-FIRE software based on the combination of design of experiment (DOE) and multiple population genetic algorithm (MPGA). Firstly, the effects of hydrogen injection timing and ignition timing on the performance of the hydrogen engine are investigated through the full factors design of experiment scheme, and then the optimum intervals of them are determined respectively. Secondly, the uniform design of experiments scheme is arranged, and the regression functions of indicated power, indicated thermal efficiency and emissions of the hydrogen engine under different working conditions are fitted. Then, the comprehensive optimization model is constructed. Finally, the optimum hydrogen injection timing and ignition timing of the hydrogen engine under different working conditions are solved based on MPGA. The results show that, compared with the standard genetic algorithm (SGA), the MPGA has faster convergence speed and higher convergence accuracy. In addition, as the load increases from low to high, the optimum hydrogen injection timing is advanced and the rate of variation increases from 0.6% to 1.1%, the optimum ignition timing is delayed and the rate of variation decreases from 29.1% to 17.8%.

The Impact of Fuel Injection Timing and Charge Dilution Rate on Low Temperature Combustion in a Compression Ignition Engine

Using high charge dilution low temperature combustion (LTC) strategies in a diesel engine offers low emissions of nitrogen oxides (NOx). These strategies are limited to part-load conditions and involve high levels of charge dilution, typically achieved through the use of recirculated exhaust gases (EGR). The slow response of the gas handling system, compared to load demand and fuelling, can lead to conditions where dilution levels are higher or lower than expected, impacting emissions and combustion stability. This article reports on the sensitivity of high-dilution LTC to variations in EGR rate and fuel injection timing. Impacts on engine efficiency, combustion stability and emissions are assessed in a single-cylinder engine and compared to in-cylinder flame temperatures measured using a borescope-based two-colour pyrometer. The work focuses on low-load conditions (300 kPa gross indicated mean effective pressure) and includes an EGR sweep from conventional diesel mode to high-dilution LTC, and sensitivity studies investigating the effects of variations in charge dilution and fuel injection timing at the high-dilution LTC condition. Key findings from the study include that the peak flame temperature decreased from ~2580 K in conventional diesel combustion with no EGR to 1800 K in LTC with low-NOx, low-soot operation and an EGR rate of 57%. Increasing the EGR to 64% reduced flame temperatures to 1400 K but increased total hydrocarbon (THC) and carbon monoxide (CO) emissions by 30–50% and increased fuel consumption by 5–7%. Charge dilution was found to have a stronger effect on the combustion process than the diesel injection timing under these LTC conditions. Advancing fuel injection timings at increasing dilution kept combustion instability below 2.5%. Peak in-cylinder temperatures were maintained in the 2000–2100 K range, while THC and CO emissions were controlled by delaying the onset of bulk quenching. Very early injection (earlier than 24 °CA before top-dead-centre) resulted in spray impingement on the piston crown, resulting in degraded efficiency and higher emissions. The results of this study demonstrate the potential of fuel injection timing modification to accommodate variations in charge dilution rates while maintaining low NOx and PM emissions in a diesel engine using low-temperature combustion strategies at part loads.

Asymmetric spray characteristics of opposed-piston two-stroke gasoline direct injection engine

The opposed-piston two-stroke (OP2S) gasoline direct injection (GDI) engine has a larger stroke-bore ratio than conventional piston-rod-crank engine, and its fuel injector and spark plug are arranged on the side wall of the cylinder liner, which puts forward new requirements for the distribution of spray and mixture formation. In this paper, an asymmetric spray method is designed on the intake and exhaust sides with the cylinder center cross-section as the reference plane. AVL-FIRE software is used to simulate the effects of injection direction, timing, and pressure on the mixture formation and equivalence ratio distribution in asymmetric spraying process. While the injection angle of the intake and exhaust side affect the spray distribution, the increase of the injection angle of the intake side is beneficial to improve the mixture uniformity, and the increase of injection angle of the exhaust side will lead to the decrease of the evaporation rate. For the injection angle of intake side (α) = 30° and the injection angle of exhaust side (β) = 15°, the fuel evaporation rate is the highest. The fuel injection timing is 220°CA at 3000 rpm and 200°CA at 6000 rpm, which can improve the fuel evaporation rate, enhance the mixture uniformity and avoid the fuel short circuit. The injection pressure of 13 MPa is set to optimize the mixture formation at the speed of 6000 rpm. At part load, the effect of two-stage injection strategy with different injection timing and injection ratio on mixture stratification is studied based on optimized results. Research indicates that mixture distribution is effected by the second injection ratio and mixture uniformity is effected by the second injection timing. The first injection timing of 220°CA and the second injection timing at 270°CA with 20% total fuel quantity can reach the ideal in-cylinder mixture distribution of 50% load at 3000 rpm.

Experimental and empirical analysis of performance, combustion and emission characteristics of diesel engine fueled with pyrolysis waste engine oil under single and split injection strategy

The present investigation studies the effects of single and split injection strategies on a diesel engine fuelled with diesel and microwave pyrolysis oil (MPO). MPO was extracted from waste engine oil (WEO) at 350–380 °C and utilized in a diesel engine after purification. The engine study was conducted using different nozzle opening pressures (NOP: 200 to 500 bar) and fuel injection timings (FIT: 17 to 27 oCA bTDC). Further, this work was extended to investigate the effect of a split injection strategy for MPO at 400 bar NOP under full load. In split injection, different split ratios, start of main injection time, and the start of post-injection time were studied. MPO's brake-specific energy consumption decreased by 7% at 400 bar NOP. NO and soot were 10% and 27% lower than diesel emissions at 400 bar NOP and bTDC 21 oCA FIT, respectively. Split injection strategy improved BTE by 1.4% and reduced NO and soot by 21% and 58% compared to the single injection strategy. The ANN model predicted the experimental results with a higher correlation coefficient (R) in the range of 0.98–0.99. Overall, the study inferred that the split injection strategy reduces exhaust emissions of MPO without affecting engine performance.

Study on injection strategy of ammonia/hydrogen dual fuel engine under different compression ratios

In order to achieve zero carbon emissions in the field of internal combustion engines, ammonia/hydrogen hybrid fuel engines are one of the best solutions. However, due to the poor ignition and combustion performance of ammonia fuel, the ammonia/hydrogen mixed fuel engine has the problems of high NOx emissions and long ignition delay, poor power performance. Therefore, this paper will study the injection strategy of ammonia/hydrogen dual fuel engine under different compression ratio to optimize the engine performance, and find the best combination of compression ratio and ammonia/hydrogen mixed fuel injection timing. In the simulation study, there are four groups of compression ratios from 13.5 to 16.5, and each group of compression ratios corresponds to eight groups of injection timing from 12°CA BTDC to 24°CA BTDC. The results show that after delaying the injection timing of ammonia/hydrogen mixture fuel, the power performance and economy of the engine are reduced, the ignition delay period is shortened, HC, CH2O, CO and soot emissions are gradually increased but at a very low level, and NOx emissions are significantly improved; After the compression ratio is increased, the engine's power performance and economy are greatly improved, HC, CH2O, CO and soot emissions are slightly higher, and NOx and N2O emissions are gradually increased. Under any combination of compression ratio coupling injection timing, the engine NOx emission can meet the Tier II emission standard. When the injection timing of ammonia/hydrogen mixed fuel is 12°CA BTDC and the compression ratio is 13.5, the NOx emission of this operation combination of ammonia hydrogen dual fuel engine can meet the Tier III emission standard. The research results of this paper can promote the engine field to zero carbon emissions and meet the Tier III emission standards, while ensuring that the engine has sufficient power.

Combined effect of intake pipe deflection and injection timing on In-cylinder flow and combustion characteristics of a gasoline direct injection Wankel rotary engine

To improve the fuel–air mixing and burning processes in a rotary gasoline engine to achieve efficient combustion, this paper used a computational fluid dynamics method to establish numerical simulation models for the in-cylinder flow and combustion of the rotary engine with a peripheral intake system. The effects of the intake pipe deflection angle and fuel injection timing on the in-cylinder flow, fuel distribution, and combustion characteristics were studied. The results showed that deflecting the intake pipe to the left generated a stronger tumble flow in the cylinder to effectively increase the turbulence intensity. A greater deflection angle provided a more obvious improvement. Moreover, deflecting the intake pipe to the left made the fuel distribution more towards the rear part of the combustion chamber and a more uniform fuel distribution in the cylinder. The spray impingement effect on the rotor surface was also greatly improved. Fuel injection timing also has a great impact on the mixing process of the combustible mixture in the cylinder. More advanced fuel injection timing resulted in longer mixing time of the fuel and air to make the mixture more uniform. Finally, deflecting the intake pipe to the left significantly increased the in-cylinder peak pressure and improved accumulated heat release. However, these effects became weakened when the fuel injection timing was retarded. Particularly, when the intake pipe was deflected to the left by 10°, the in-cylinder peak pressure increased most with a 27.9% increase compared with the original design. When the intake pipe was deflected to the left by 30°, the turbulent kinetic energy increased most with a 93% increase compared with the original design. The intake pipe was deflected by 10° to the left and the fuel injection timing was 250° CA BTDC, which is the most helpful for improving engine performance. This study can provide guidance for design of the injection and intake systems of the rotary engine.

Thermofluids analysis of combustion, emissions, and energy in a biodiesel (C11H22O2) / natural gas heavy-duty engine with RCCI mode (Part II: Fuel injection time/ Fuel injection rate)

• With the same energy production by diesel and biodiesel, the biodiesel combustion start earlier because of more oxygen content. • The biodiesel fuel (C11H22O2) used in this research is a new fuel derived from algae and is being simulated for the first time at this level for heavy-duty biodiesel engine. • The maximum pressure for biodiesel fuel is approximately equal to 9.12 MPa and for diesel fuel is equal to 8.9 MPa. • By advancing the injection start time from 16 to 8 crank angle degrees, the mass of soot is facing a decreasing trend. Among the measures that improve the combustion process and reduce emissions in the design of dual-fuel engines is the use of the RCCI combustion strategy. This paper attempts to investigate the effects of biodiesel and diesel fuels, fuel injection time, and fuel injection rate in the RCCI combustion mode. In this study, using CONVERGE CFD commercial software and SAGE combustion model for the simulation. Accordingly, the geometry of a biodiesel (C 11 H 22 O 2 ) / natural gas dual-fuel engine (Caterpillar 3401E) was exploited for experimental tests and numerical simulations. Results show that: The pressure inside the combustion chamber is especially greater from -12° to +10° crank angle for biodiesel, in fact, the maximum pressure for biodiesel fuel is approximately equal to 9.12 MPa and for diesel fuel is equal to 8.9 MPa. The mass of HC emissions for the two fuels is almost equal, but the mass of CO emissions for biodiesel is higher than diesel. By reducing the duration of fuel injection from 16° to 8° crank angle, the mass of soot is facing a decreasing trend, and this amount lowers from 0.065 to 0.00086 mg. Moreover, the indicated mean effective pressure (IMEP) and production work have increased from Case A (8 and 16 mg biodiesel in the first and second injection) to C (16 and 8 mg biodiesel in the first and second injection), and the knocking rate is reached from 3.4 to 6.6.