EXPERIMENTAL INVESTIGATION ON THE EFFECT OF ADDING CYCLOHEXANONE TO GASOLINE IN SI ENGINE EMISSIONS AND PERFORMANCE

The aim of the present work is to investigate the influence of adding some ketone compounds on the performance, emissions, heat balance and exhaust gas temperature of spark ignition engine. The ketone used in this study is cyclohexanone (C6H10O). This ketone has been added to the base fuel (gasoline) with three concentration ranges (3, 6 and 9%) respectively. All experimental tests were carried out on gasoline engine type (Nissan QG18DE), four cylinders, 4-stroke, direct injection, with compression ratio (9.5:1). The acquired results showed that adding of ketones affect the physical properties of gasoline. Where the density changed from (710 kg/m3) for net gasoline to (740.8 kg/m3) for cyclohexanone at adding ratio of (9%). The octane number also increased from (86) for pure gasoline to (97.7) for fuel with 9% cyclohexanone. The calorific value will be decrease from (43000 kJ/kg) for gasoline to (42077.5) for cyclohexanone at adding ratio of (9%). The addition of ketones improves the emissions characteristic of engine. The best reduction of (UHC, CO_2, CO and NOx) was (49.04, 22.43, 35.02 and 42.14%) recorded by cyclohexanone addition at ratio of (9%). In the case of performance, all parameters of performance improved by adding ketones. The brake specific fuel consumption reduced by (8.9%) by adding (9%) of cyclohexanone which recorded as the best reduction through all types. The best increment of brake power, brake thermal efficiency, brake mean effective pressure and volumetric efficiency was (17.3, 8.98, 17.25 and 12.7%) is achieved by adding (9%) of cyclohexanone. Also, the exhaust gas temperature will be increase by adding ketones. The percentage increasing of exhaust gas temperature was (28.31%) recorded by cyclohexanone addition at ratio of (9%). In the case of heat balance, the best increment of total heat internal energy was (6.59) at (9%) of cyclohexanone.

A novel method to overcome the shortcomings of turbocharging a single cylinder diesel engine

Single-cylinder diesel engines are generally not turbocharged because of highly pulsating exhaust gas flow, resulting in increased speed fluctuations and reduced turbine performance. In the present work, a novel and simple method is proposed wherein an exhaust plenum is placed before the turbine to reduce the flow fluctuations. A production light-duty naturally aspirated (NA) diesel engine modified into the turbocharged version was incorporated with an exhaust plenum. Steady-state experiments were performed with the base naturally aspirated engine, the turbocharged version without an exhaust plenum (conventional pulse turbocharging), and the turbocharged version with the exhaust plenum. The present work attempts to establish the limitations of conventional pulse turbocharging in a single-cylinder diesel engine unavailable in the existing literature. Though the conventional pulse turbocharged version could deliver a boost pressure of about 2 bar (absolute), a brake power reduction of 40% and the associated drop in brake mean effective pressure was observed compared to the base NA engine due to high exhaust back pressures. The pumping work was four times higher in conventional pulse turbocharging than the NA engine, thus reducing the performance. After validating the simulation models, a one-dimensional simulation tool was used to evaluate the effect of incorporating exhaust plenum before the turbine. Simulated results predicted the brake power output within a 3% error for the NA and plenum turbocharging configurations. An optimal plenum volume was arrived at using the validated simulation model. Subsequent experiments on the turbocharged engine with the plenum in place showed a significant improvement in the engine performance and reduced exhaust emissions compared to the NA version. Brake power output was enhanced by 25%, which indicated improved thermal efficiency of 2%. Compared to the NA version, the soot, carbon monoxide (CO) and unburned hydrocarbon HC emissions were reduced by 93%, 88%, and 53%, respectively. However, an increase in oxides of nitrogen (NOx) emissions was seen, which can be controlled with suitable mitigation methods taking advantage of the significantly lower soot levels. Thus, the proposed method of placing an exhaust plenum before the turbine makes turbocharging viable on single-cylinder diesel engines with performance improvement and emission reduction when suitable NOx mitigation measures are adopted.

Impact of low reactivity fuel type on low load combustion, emissions, and cyclic variations of diesel-ignited dual fuel combustion

In this study, cyclic variations in dual fuel combustion with diesel ignition of three different low reactivity fuels (methane, propane, and gasoline) are examined under identical operating conditions. Experiments were performed on a single cylinder research engine (SCRE) at a low load of 3.3 bar brake mean effective pressure (BMEP). The start of injection (SOI) of diesel was varied from 280 to 330 absolute crank angle degrees (CAD). Engine speed, rail pressure, and boost pressure were held constant at 1500 rpm, 500 bar, and 1.5 bar, respectively. The energy substituted by the low reactivity fuel was fixed at 80% of the total energy input. It was found that diesel-methane (DM) and diesel-propane (DP) combustion were affected by diesel mixing to a greater extent than diesel-gasoline (DG) combustion due to the higher reactivity of gasoline. The magnitude of low temperature heat release was greatest for DG combustion followed by DM and DP combustion for all SOIs. The ignition delay for DG combustion was the shortest, followed by DM and DP combustion. DM and DP combustion exhibited more cyclic variations than DG combustion. Cyclic variations decreased for DM and DP combustion when SOI was advanced; however, DG combustion cyclic variations remained essentially constant for all SOIs. Earlier SOIs (280, 290, 300, and 310 CAD) for DM and (280, 290, and 300 CAD) for DP combustion indicated some prior-cycle effects on the combustion and IMEP (i.e. some level of determinism).

PERFORMANCE ASSESSMENT OF A LARGE INTERNAL COMBUSTION ENGINE DUE TO INLET AIR COOLING AND DEHUMIDIFICATION: GT-POWER SOFTWARE SIMULATION

Large internal combustion engines (ICEs) performance is limited by knocking phenomenon due to harsh ambient conditions such as hot temperature and excessive humidity. The performance of these engines can be enhanced by cooling and dehumidifying the inlet air on turbocharger upstream under safe operation conditions through a cooling coil heat exchanger, hence, increasing the power output as well as reducing the brake specific fuel consumption and pollutant specific emissions. Analysis have been performed in the GT-POWER software through a 1-D thermodynamic modelling of the Wärtsilä W20V34SG engine, making it possible to verify the influence of cooled and dehumidified ambient air, considering a temperature range from 9.5°C (282.7 K) to 15.5°C (288.7 K), while keeping 1 bar for pressure and relative humidity of 100%. Furthermore, the brake mean effective pressure (BMEP) has been set from 20 to 23.45 bar with a step of 1.15 bar. Such simulations are aimed to find the maximum air temperature at the cooling coil outlet in which the average of maximum cylinder pressures does not exceed the safety limit pressure of 186 bar while maintaining control on the wastegate valve. As a result, it was possible to evaluate that the maximum temperature to be chosen, under the conditions already mentioned, should be lower than 13.8°C (287 K).

Experimental Analysis of Water Pressure and Temperature Influence on Atomization and Evolution of a Port Water Injection Spray

Port water injection (PWI) is considered one of the most promising technologies to actively control the increased knock tendency of modern gasoline direct injection (GDI) engines, which are rapidly evolving with the adoption of high compression ratios and increased brake mean effective pressure levels in the effort to improve their thermal efficiency. For PWI technology, appropriately matching the spray evolution and the intake system design along with obtaining a high spray atomization quality, are crucial tasks for promoting water evaporation so as to effectively cool down the air charge with moderate water consumption and lubricant dilution drawbacks. In the present paper, a detailed experimental analysis of a low-pressure water spray is presented, covering a lack of experimental data on automotive PWI systems. Phase doppler anemometry and fast-shutter spray imaging allowed us to investigate the influence exerted by the injection pressure level and by the water temperature on spray drop size and global shape, obtaining a complete database to be used for the optimization of PWI systems. The obtained results evidence how significant benefits in terms of atomization quality can be obtained by adopting injection pressure and water temperature levels compliant with standard low injection pressure technologies.

Experimental Investigation on the Performance of a CI Engine Fueled with Waste Cooking Oil Biodiesel Blends

In this study, different performance parameters of a Compression Ignition (CI) engine fueled with waste cooking oil biodiesel blends with diesel in different percentage volumes of 5 % biodiesel and 95 % diesel (W5), 10 % biodiesel and 90 % diesel (W10), 15 % biodiesel and 85 % diesel (W15) and 20 % biodiesel and 80 % diesel (W20) were tested experimentally. First, biodiesel was produced from waste cooking oil by transesterification process. The physical-chemical properties of biodiesel and W20 were tested. The tested properties of W20 were found to American Society for Testing and Materials (ASTM) standards near to diesel fuel. Subsequently, test of diesel and biodiesel blended fuels were carried out using 15:1 compression ratio on Kirloskar Single Cylinder Compression Ignition Engine at 1500 rpm on varying loads. The engine performance parameters for biodiesel blends such as Indicated Power (IP), Brake Power (BP), Brake Mean Effective Pressure (BMEP), Brake Thermal Efficiency (BTE), Specific Fuel Consumption (SFC) and Mechanical Efficiency (ME) against load in comparison to diesel fuel were obtained and verified those with diesel fuel. IP for diesel, W5, W10, W15 and W20 at load of 12 kg are 4.3 kW, 4.8 kW, 4.7 kW, 4.75 kW and 4.2 kW respectively. ME of W20 at 12 kg load is less by 4.1 % than diesel. The difference in SFC of diesel and W20 at 12 kg load was 0.27 kg/kWh. The experimental outcomes confirm that the IP and SFC of blended biodiesel were slightly superior. Correspondingly, BP and BMEP were also found comparable to diesel fuel.

Performance Characteristics of Pine Oil Mixed Diesel Fueled Single Cylinder Four Stroke Diesel Engine

In this study, biodiesel from the stem of Pinus roxburghii was prepared by steam distillation process. Consequently, the physical and thermal properties of pine biodiesel (P100), and 20 % pine-biodiesel and 80 % diesel (P20) were tested on American Society for Testing and Materials (ASTM) standards. The test results confirmed that the thermophysical properties of pine biodiesel and its blend were suitable for the fuel in diesel engine without any modification in the test engine. Eventually, the engine performance and combustion parameters were evaluated for pine-biodiesel blend for 5 % biodiesel and 95 % diesel (P5), 10 % biodiesel and 90 % diesel (P10), 15 % biodiesel and 85 % diesel (P15) and P20, and compared with diesel on Kirloskar Single Cylinder Compression Ignition Engine for a compression ratio of 15:1. In the midst of those in different blends evaluated, P15 showed the better brake specific fuel consumption (BSFC) i.e 18.75 % lower than diesel fuel particularly up to 50 % of the engine load. However, at higher load, decrease rate in BSFC of P15 fuel is lower than engine load up to 50 %. Similarly, brake thermal efficiency (BTE) of P15 increases to 13.5% mainly on 50 % loading condition of the engine. At above, increment rate of BTE of pine oil biodiesel compared to diesel decreases. The brake power (BP) and brake mean effective pressure (BMEP) of P15 also found nearer to diesel. However, the BP of P15 found higher compared to diesel in all loading conditions. Thus, from the experimental investigations, P15 blend of pine oil biodiesel was found to be amenable for its use in compression ignition (CI) engine without any modification, as the BTE and SFC were found to better and, BP, indicated power (IP) and BMEP were also found nearer to diesel fuel.

Numerical study on the effects of intake charge on oxy-fuel combustion in a dual-injection spark ignition engine at economical oxygen-fuel ratios

In order to decrease Carbon Dioxide (CO2) emissions, Oxy-Fuel Combustion (OFC) technology with Carbon Capture and Storage (CCS) is being developed in Internal Combustion Engine (ICE). In this article, a numerical study about the effects of intake charge on OFC was conducted in a dual-injection. Spark Ignition (SI) engine, with Gasoline Direct Injection (GDI), Port Fuel Injection (PFI) and P-G (50% PFI and 50% GDI) three injection strategies. The results show that under OFC with fixed Oxygen Mass Fraction (OMF) and intake temperature, the maximum Brake Mean Effective Pressure (BMEP) is each 5.671, 5.649 and 5.646 bar for GDI, P-G and PFI strategy, which leads to a considerable decrease compared to Conventional Air Combustion (CAC). [Formula: see text], [Formula: see text] and [Formula: see text] of PFI are the lowest among three injection strategies. With intake temperature increases from 298 to 378 K, the reduction of BMEP can be up to 12.68%, 12.92% and 12.75% for GDI, P-G and PFI, respectively. Meantime, there is an increase of about 3% in Brake Specific Fuel Consumption (BSFC) and Brake Specific Oxygen Consumption (BSOC). Increasing OMF can improve the performance of BMEP and BSFC, and the trend is more apparent under GDI strategy. Besides, an increasing tendency can be observed for cylinder pressure and in-cylinder temperature under all injection strategies with the increase of OMF.

Evaluation of the performance and gas emissions of a tractor diesel engine using blended fuel diesel and biodiesel to determine the best loading stages

Fossil fuels are the main energy sources responsible for harmful emissions and global warming. Using biodiesel made from waste deep-frying oil as an alternative fuel source in diesel engines has drawn great attention. This biodiesel is produced using the transesterification process and blends with mineral diesel at Faculty of Agriculture Saba Basha, Alexandria University, Egypt. The turbocharged diesel engine of a Kubota M-90 tractor was tested. The objectives of this work are to test tractor as a source of power in the farm using waste deep-frying oil biodiesel to utilize waste frying oils (WFO) in clean energy production on the farm and determine the best engine loading stages to maximize engine efficiencies for different fuel blends and reduce the environmental impact of gas emissions from tractor diesel engines in the farms. The experiment design was factorial, with two factors, where the first was the engine load (0%, 25%, 50%, 75%, and 100%) and the second was fuel blend (0%, 5%, 20%, and 100% biodiesel), and the effects of loading stages and biodiesel percentage on engine performance indicators of engine speed, power take off torque, power take off power, brake power, brake mean effective pressure, brake thermal efficiency, brake specific fuel consumption, and gas emissions were studied. The experimental results indicated that engine load percentage and fuel blend percentage significantly affected all studied characters, and the best engine loading stages were between 25 and 75% to maximize engine efficiency and minimize the specific fuel consumption and gas emissions. Increasing the biodiesel percentage at all loading stages resulted decreasing in Engine brake power (BP), brake thermal efficiency, Power take-off (PTO) torque, and brake mean effective pressure and increases in brake specific fuel consumption. Increasing the engine load resulted in decreases in O2 emissions and increases in CO2, CO, NO, and SO2 emissions. Increasing the biodiesel percentage in the blended fuel samples resulted in increases in O2 and NO emissions and decreases in CO2, CO, and SO2 emissions. The use of biodiesel with diesel fuel reduces the environmental impact of gas emissions and decreases engine efficiency.