Small Direct Injection Diesel Engine Research Articles

Sampled-data model validation: An algorithm and experimental setup of dual fuel IC engine

This research work investigates the usage of hybrid based Artificial Neural Network-Harris Hawks and whale optimization algorithm (ANN-HHOWOA) for forecast of emission properties and performance of small utility single cylinder direct injection (DI) diesel engine inlet with rice bran biodiesel blends under dual fuel mode along with biogas. This Artificial Neural Network based hybrid Harris Hawks and whale optimization algorithm was developed and optimized to forecast the values of brake thermal efficiency (BTE), hydrocarbon (HC), carbon monoxide (CO) and carbon dioxide (CO2) based on the gathered input data from the experimental setup of dual fuel engine by varying engine operating load, blends of rice bran biodiesel, air fuel ratio and injection timings. To experimentally validate the results by using hybrid based Artificial Neural Network-Harris Hawks and whale optimization algorithm (ANN-HHOWOA), 500 trial runs were performed on objective functions of gathered data to find optimal solution. 70% of data were used for training, 15% for testing and other 15% were used for validation. It has been concluded that hybrid based Artificial Neural Network-Harris Hawks and whale optimization algorithm (ANN-HHOWOA) gave remarkable results with classification rate 98.6667% which is much better than other meta-heuristic algorithms. It is found that Artificial Neural Network based hybrid Harris Hawks and whale optimization algorithm is a very useful tool for prediction and optimization of combustion performance and emissions properties of dual fuel engine fuelled with biogas-biodiesel blends.

The effect of operating parameters on performance and emissions of DI diesel engine fuelled with Jatropha biodiesel

In the present investigation the combustion, performance and emission analysis of a small Direct Injection diesel engine was done in order to find the effect of Jatropha Methyl Ester as a fuel on the engine. In this study, speed, load and fuel injection timing were varied according to (3 × 3 × 3) full factorial design and cylinder pressure, fuel consumption, smoke and emissions of HC and NOx were measured. For understanding the nature of cylinder pressure rise and combustion characteristics of Jatropha Methyl Ester and diesel fuel, the cylinder pressures were recorded for all the combinations of load, speed and injection timing. Comparative study of engine emissions and fuel economy was carried between Jatropha Methyl Ester and Diesel. The response surface quadratic models were generated for the four output parameters viz. smoke, brake specific fuel consumption, unburned hydrocarbons and NOx relative to the three input parameters: speed, load and injection timing. The response surface equations were then solved as multi-objective nonlinear constrained optimization problem using the Design-Expert 10.0 software, which makes use of the desirability functions. Further, optimization was done to search the optimum combinations of load, speed, and injection timing which give the possible minimum emissions, well lower than the set values. The maximum rate of heat release was found to be higher for diesel than that of JME at all the speeds, loads and injection timings combinations. The maximum reduction of 72.56% in smoke level was observed at 12°CA btdc, 70% load and at 3100 rpm when JME was used as fuel. Maximum increase of 30% in NOx emission was found at 15° crank angle, 70% load and 2300 rpm when JME was used as fuel. Response surface methodology (RSM) was found to be a useful technique for modeling engine responses using three input parameters viz. speed, load and injection timing.

Exergy analysis of small DI diesel engine fueled with waste cooking oil biodiesel

ABSTRACT This study investigates the merits of exergy analysis over energy analysis for small direct injection (DI) diesel engine using the blend of waste cooking oil biodiesel and petroleum diesel. Taguchi’s “L’ 16” orthogonal array has been used for the design of experiment. The engine tested at different engine speeds, load percentages, and blend ratios, using the waste cooking oil biodiesel. Basic performance parameters and fuel input exergy, exergetic efficiency (second law efficiency), exergy associated with heat transfer, exergy associated with the exhaust gas and destruction of exergy are calculated for each blend of waste cooking oil biodiesel and diesel. Results show that the optimum operating conditions for minimum brake-specific fuel consumption (BSFC) and exergy destruction are achieved when engine speed at 1900 rev/min, load percentage is 75%, and the engine is fueled with B40.

Parametric optimisation of exergy destruction in small DI diesel engine fuelled with neem biodiesel using the Taguchi method

ABSTRACTLarge amount of emissions from vehicles have led to the degradation of urban air quality and have resulted in serious health issues. Biodiesel, a substitute fuel for diesel engine, is receiving great attention worldwide. This work investigates the merits of using neem-biodiesel and diesel blends for single cylinder small direct injection diesel engine. The energy (the first law) and exergy (the second law) analyses of direct injection diesel engine using neem-biodiesel blends have been presented. Taguchi’s ‘L’ 16’ orthogonal array has been used for the design of experiments. The engine was tested at different engine speeds, load percentages and blend ratios, using neem biodiesel. The results show that the optimum operating conditions for minimum brake specific fuel consumption are achieved when the engine speed is 1900 rev/min, load percentage is 75 and the engine is fuelled with B40.

Experimental investigation on the influence of engine operating conditions on combustion and nanoparticle emission characteristics of a small DI diesel engine

The influence of variations in engine speed, injection pressure, injection timing, and multiple injection strategies on the combustion and nanoparticle characteristics of a small Direct injection (DI) diesel engine was experimentally investigated. To measure the size distribution and number concentration of particle emissions, a rotating disk thermo-diluter (dilution system), a Condensation particle counter (CPC), and a Scanning mobility particle sizer (SMPS) were used. The injection pressure was changed from 60 MPa to 120 MPa, at an engine speed of 1200 rpm. Injection timing was varied from Before top dead center (BTDC) 40˚ to Top dead center (TDC). To investigate the effect of multiple-injection strategies, the injection strategies consisted of two pulse signals with different dwell time. The experimental results show that the peak combustion pressure and Rate of heat release (ROHR) profile are increased and ignition delay is shortened with the increase of injection pressure from 60 MPa to 120 MPa. The concentration of soot emission for 120 MPa is lower than that of 60 MPa at advanced injection timing from TDC up to BTDC 25°. As the injection timing advances to over BTDC 30°, soot emissions rapidly increase and the high injection pressure case (120 MPa) creates more emissions than the 60 MPa case. The overall trends of total particle number are relatively increased with high injection pressure for single injection conditions. In the advanced injection timings of over BTDC 30°, the trend of total particle number is high for all injection pressures. For multiple injections, the peak combustion pressures and ROHR of multiple-injection strategies are slightly lower compared with those of single-combustion results. Comparing the multiple injection strategies, soot emission is reduced with the retard of second injection timing (-30°+5°). The overall trends of particle size and total number for the 7 mg+3 mg case revealed the lowest level compared with other cases, which is 50% lower than that for the 5 mg+5 mg case. When compared with single injection results, the total particle number and Dp of multiple injection cases were eventually lower.

Micro-structural and components evolution mechanism of particular matter from diesel engines with non-thermal plasma technology

The present study is about the influence of non-thermal plasma (NTP) technology on soot emissions and physico-chemical properties (morphology, particle size, chemical composition and ignition temperature) of diesel PM. Experiments have been carried out using a small direct injection diesel engine with NTP technology based on a bench test. The physico-chemical properties of PM samples were detected by GC–MS, SEM, EDX, and TGA. PM samples after NTP treatment consisted of mainly hydrocarbons with less than 18 carbon atoms and few hydrocarbons with higher than 20 carbon atoms. Analysis by SEM and EDX showed that the agglomeration degree and the mean spherule diameters were markedly reduced by NTP oxidation. TGA showed that the ending combustion temperatures of PM samples in oxygen environment were 670.03 °C and 550.54 °C before and after NTP treatment, respectively. The mean temperature difference was nearly 120 °C, which indicated that NTP technology could effectively reduce the burning combustion temperature of diesel PM emissions.

Effects of High EGR Rate on Dimethyl Ether (DME) Combustion and Pollutant Emission Characteristics in a Direct Injection Diesel Engine

This study investigated the effects of high exhaust gas recirculation (EGR) rates on dimethyl ether (DME) fuel combustion performance, exhaust emissions and particle emission characteristics in a small direct injection diesel engine under various injection timings. To examine the effect of EGR and injection timings, the experiment was performed under high EGR rates (0%, 30%, 50%) and injection timings were varied from 40° before top dead center (BTDC) to top dead center (TDC) of the crank angle to examine the effects of early injection of DME fuel. The combustion pressures and heat release rates for different EGR rates followed similar trends. As the injection timing was advanced, the indicated mean effective pressure (IMEP) differed little in response to EGR rate in the range from TDC to 25° BTDC, and more for crank angles beyond 25° BTDC. DME combustion exhibited very little soot emission, but soot emission increased slightly with EGR rate. The use of high EGR during combustion produced very low NOx concentrations but increased HC and CO emissions for advanced injection timings from 25° BTDC to 40° BTDC. The use of EGR increased both the emissions of total particle number and particle volume over the whole range of the injection timings; for all cases, total particle volume decreased as injection timing was advanced.

Influence of 1-butanol addition on diesel combustion with palm oil methyl ester/gas oil blends

PME (Palm oil methyl ester) is a promising alternative fuel among biodiesels, because palm oil is the most produced feedstock and its yield is the highest among vegetable oil crops. However, PME has a serious drawback in its relatively high pour point. The aim of this investigation is to extend the range of utilization of PME by improving its low temperature fluidity. The present study used three kinds of blended fuels composed of PME/gas oil/1-butanol to show the effect of lower pour points. Neat PME has a pour point of 19 °C, for a PME blend with 20% PME (PME20) the pour point is −5 °C, and with 40 mass% 1-butanol blended into the PME20 the pour point is −10 °C. Using four kinds of PME/gas oil blends as the base fuels the influence of 1-butanol addition on the engine performance, combustion characteristics, and exhaust emissions of a small single cylinder DI (direct injection) diesel engine was examined. The brake thermal efficiency of the base fuels changed little when 1-butanol was added up to 40 mass%. The results also showed that at the rated output condition the smoke emissions decreased considerably with increasing 1-butanol addition ratios.

The use of Koroch seed oil methyl ester blends as fuel in a diesel engine

An experimental investigation was carried out on a small direct injection (DI) diesel engine, fuelling the engine with 10% (B10), 20% (B20), 30% (B30) and 40% (B40) blending of Koroch seed oil methyl ester (KSOME) with diesel. The performance and combustion characteristics of the engine at various loads are compared and analyzed. The results showed higher brake specific fuel consumption (BSFC) and lower brake thermal efficiency (BTE) for the KSOME blends. The engine indicated power (IP) was more for the blends up to B30, but found to be reduced for the blend B40 when compared to that of diesel. The engine combustion parameters such as pressure crank angle diagram, peak pressure, time of occurrence of peak pressure, net heat-release rate, cumulative heat release, ignition delay and combustion duration were computed. The KSOME blends exhibited similar combustion trend with diesel. However, the blends showed an early start of combustion with shorter ignition delay period. The study reveals the suitability of KSOME blends up to B30 as fuel for a diesel engine mainly used in generating sets and the agricultural applications in India without any significant drop in engine performance.

Optimization of Injection System Parameters and EGR on Jatropha Biodiesel Engine using Taguchi Approach

The diesel engine injection system parameters apart from the operating parameters such as load and speed significantly affect its performance and exhaust emissions. The effect is even adverse sometimes when the engine is tried with some alternative fuels, such as Jatropha biodiesel due to its physico-chemical properties. For better performance and to meet out stringent emission norms, these parameters have to be optimized. An experimental investigation and analysis carried out to simultaneously optimize injection system parameters and exhaust gas recirculation (EGR) levels of small direct injection diesel engine for lower fuel consumption and higher thermal efficiency and peak cylinder pressure is presented in this paper. During the experiments, the different parameters such as fuel type, injection timing, injector opening pressure, nozzle configuration, nozzle tip protrusion, percentage of exhaust gas recirculation (EGR), load torque and speed were changed. Taguchi's signal-to-noise ratio approach was applied to obtain an optimal setting of these parameters. From the experimental results and further analysis it is concluded that under 95% confidence interval the injection timing 340°CA, injector opening pressure 250 bar, nozzle configuration 5x0.18, EGR 0%, load torque 15Nm, speed 1800rpm with Jatropha biodiesel, gave the maximum peak cylinder pressure, while the lowest BSFC with diesel fuel was obtained with nozzle configuration 4x0.18, load torque 15Nm and speed 1800rpm and the highest brake thermal efficiency with nozzle configuration 4x0.18, tip protrusion 2mm, load torque 15Nm and speed 1800rpm. However, the significant control parameters responsible for brake thermal efficiency with their percentage contribution were load torque (79.13%), speed (17.54%), nozzle configuration (1.33%) and tip protrusion (0.96%).

A procedure to reduce pollutant gases from Diesel combustion during European MVEG-A cycle by using electrical intake air-heaters

While intake air heating is a widespread technology used in heavy duty diesel engines, it rarely appears in the field of HSDI diesel engines. Nevertheless, intake air heating is currently under study as a possible alternative to glow plugs for cold start assistance in HSDI diesel engines. Since the use of intake air heaters involves a cylinder-head simplification, this solution presents both economical and combustion advantages. Despite of the negative impact of the high intake temperatures on NO x emissions, intake air heating reduces significantly HC and CO emissions during warm up due to combustion improvement. While the potential of intake air heating technology to assist cold start is proved, the present paper is devoted to the evaluation of the intake air heating technology potential to reduce pollutant emissions from Diesel combustion. To deal with this objective a deep analysis of both glow plug and intake air heating technology behaviour during the MVEG-A cycle is done. Experimental tests are carried out on a small turbocharged direct injection Diesel engine in an engine-in-the-loop (EIL) approach. Results prove that an optimal intake air heating strategy together with an adapted air loop control calibration can improve HC, CO and NO x emissions with only a scarce PM increase.

Diesel Combustion Characteristics of Palm Oil Ethyl Ester

In order to utilize palm oil ethyl ester (PEE) as an alternative diesel fuel, the combustion characteristics and exhaust emissions are investigated using a small direct injection diesel engine, and are compared with palm oil methyl ester (PME), rapeseed oil ethyl and methyl esters (REE and RME) and the gas oil. As a result, PEE has lower pour point compared with PME. The thermal efficiency of PEE is almost the same as those of the other test fuels. PEE and PME have lower exhaust emissions compared with the other test fuels. Although CO and smoke emissions of PEE are slightly higher than that of PME, NOx and HC emissions of PEE are almost the same as that of PME. It is concluded that PEE can be used as an alternative petroleum diesel fuel.

The use of micro-orifice nozzles and swirl in a small HSDI engine operating at a late split-injection LTC regime

This paper describes the investigation of low-temperature combustion (LTC) in a small single-cylinder research high-speed direct injection (HSDI) diesel engine. This engine is representative of passenger car turbocharged diesel engines equipped with a particulate trap and an oxidation catalyst. A medium-load operation mode has been evaluated where the diesel fuel is injected in two injection events close to top dead centre, and high levels of exhaust gas recirculation are used (near stoichiometric air-fuel ratios). The combustion is characterized by extremely low emission of nitrogen oxides (of the order of 10–15 parts per million) and low combustion noise. Three injector nozzles have been tested with 6, 12, and 18 orifices. The orifice diameters are in the range 70–120 μM and have been chosen to obtain injector nozzles with the same hydraulic flow. All three nozzles have been tested at a condition without swirl and at a mean swirl number of 1.7. The effects of the nozzle orifice number and swirl have been investigated by means of analysis of fuel spray, combustion, and emissions. It was found that when the number of orifices is increased, the rate of heat release during the first half of combustion is enhanced. However, during the second part of the combustion, interactions between sprays worsen the air-fuel mixing process and reduce the rate of heat release. Swirl was found to amplify the effects of spray interactions. While normally swirl speeds up the combustion in the second half of the combustion, the opposite happens when spray-spray interaction occurs.

Turbulent gas jets and diesel-like sprays in a crossflow: A study on axis deflection and air entrainment

The interaction between a turbulent gas jet/diesel spray and a crossflow has been analysed. This phenomenon is a simplification of a more complex one that takes place in the combustion chamber of small direct injection diesel engines, and its study will help to better understand this more complex case. The two main aspects analysed here are axis deflection and air entrainment. It was found that both aspects are related to each other, and that the air/jet (or air/spray) momentum flux ratio is very relevant in the phenomenon. Scaling laws for the axis deflection of a jet/spray were obtained, and an original method to obtain fuel concentration along the axis of a jet/spray in a crossflow has been established. Gas jets and diesel sprays are found to be very similar even when they interact with a crossflow.

Effect of Compression Ratio and Spray Injection Angle on HCCI Combustion in a Small DI Diesel Engine

An experimental investigation was performed on a small direct injection (DI) diesel engine equipped with a common-rail injection system to find the optimal operating conditions of a homogeneous charge compression ignition (HCCI) engine. It is generally agreed that NOx is formed within the stoichiometric diffusive flame and may continue to form in the hot combustion products and that particulate matter is formed under a rich fuel/air mixture condition. Therefore, if an adequately diluted fuel/air mixture is formed before the start of ignition by prolonging the ignition delay, a homogeneous lean mixture is burned at a low temperature. In this way, simultaneous reduction of NOx and soot can be achieved. To realize this fundamental concept and find the optimal operating conditions, injection timing was varied from top dead center (TDC) to 80° before TDC and up to 45% of exhaust gas recirculation (EGR) was tested. The features of the base engine were modified as follows. First, the geometric compression ratio was reduced from 17.8 of the base diesel engine to 15 for expanding ignition delay by modification of the piston shape. Second, the injection angle was reduced from 156° of the base engine to 60° to reduce fuel deposition on the wall of the combustion chamber when using early injection timing. Experimental results showed that clean operating conditions existed either at an early start of injection timing with/without EGR or at a very late start of injection timing near TDC with high rates of EGR.

Parameter optimization of a diesel engine to reduce noise, fuel consumption, and exhaust emissions using response surface methodology

The conflicting effects of the operating parameters and the injection parameter (injection timing) on engine performance and environmental pollution factors is studied in this paper. As an optimization objective, a 3.5 kW small direct injection diesel engine was used as the test engine, and its speed, load, and static injection timing were varied as per 4 × 4 × 3 full factorial design array. Radiated engine noise, smoke level, brake specific fuel consumption, and emissions of unburned hydrocarbons and nitrogen oxides were captured for all test runs. Objective functions relating input and output parameters were obtained using response surface methodology (RSM). Parameter optimization was carried out to control output responses under their mean limit using multi-objective goal programming and minimax programming optimization techniques.

Investigation of diesel engine operating and injection system parameters for low noise, emissions, and fuel consumption using Taguchi methods

In order to optimize the performance of a small direct injection (DI) diesel engine with respect to noise, emissions, and fuel economy, an experimental investigation was undertaken using Taguchi methods. A single-cylinder 3.5 kW diesel engine was selected for performance tests at different levels of two operating parameters (speed and load) and six injection parameters of the engine (static injection timing, plunger diameter, nozzle valve opening pressure, nozzle hole diameter, number of nozzle holes, and nozzle tip protrusion). These controlled parameters were varied at two levels, and the resulting changes in responses were investigated, namely engine noise, combustion noise, smoke, brake specific fuel consumption (b.s.f.c.), and emissions of unburned hydrocarbons (HC), oxides of nitrogen (NO x), and carbon monoxide (CO) were investigated. The optimum values of engine noise, combustion noise, smoke, emissions, and b.s.f.c. could be predicted using signal-noise ( S/N) ratios, and a relevant combination of controlled input parameters was specified. Results of confirmation runs of the engine showed good agreement with the predicted quantities of interest based on Taguchi analysis. The relative importance of the controlled parameters to the above responses was evaluated in terms of the percentage contributions of the parameters using analysis of variance (ANOVA). The Taguchi method of experimental design was found to be robust and more cost effective for understanding the relationship between diesel engine parameters and noise, emissions, and b.s.f.c. than full factorial design.

322 小形直噴ディーゼル機関の二段燃焼の研究(OS-1 直噴ディーゼル機関,研究発表講演)

The early injection quantity in small direct-injection diesel engines is limited by the wall-wetting. Accordingly, a narrow spray angle nozzle was applied in order to keep the early injected fuel in the combustion chamber. Moreover, the two stage combustion that the second injection spray near the top dead center impinges and diffuses on the center projection of the combustion chamber has been investigated.

Adaptability of Direct Injection Impinging Distribution Combustion System to a Small Diesel Engine

An impinging distribution spray combustion system, named OSKA, was applied to a small direct injection diesel engine in order to reduce the wall quenching originated emittants, e. g. SOF and THC. Experimentation was carried out using a single cylinder engine of bore × stroke of 93×92 mm, with varying the piston cavity geometry and, the injection and impinging conditions. The combustion chamber geometry has great effects on emission characteristics and performances. KIVA 3 numerical analysis on the flow characterization has helped to interpret these effects. It also clarified the effect of dimple.

小型高速機関の低温始動性における燃料油性状の影響

Coastal fishing vessels use high speed diesel engines on board. A lot of problems regarding cold start are reported, for example, white smoke emission in winter when low ignition quality fuel is used. We conducted cold start tests for a small size direct injection diesel engine under the conditions of the fuels with a variety of cetane index and evaporability. White smoke emission become worse when the fuel with low cetane index was used, or the fuel with higher 50% distillate temperature was used. The effect of increasing the 50% distillate temperature with 30 °C was equivalent to decreasing cetane index with five. We also observed high CO emissions of cold start when low cetane index fuels were used.