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1.
Environmental pollution due to emissions from an IC engine is an important problem appearing under cold weather conditions. In this study, air pre-heating as well as pre-heating of the IC engine is done to ensure efficient combustion and reduction in emission level during a cold start. A thermal energy storage device (TESD) and an air pre-heater is designed and tested for the purpose of pre-heating. The TESD contains paraffin as a phase-changing material which works on the principle of absorption and rejection of thermal energy during the phase-changing temperature Normal, discharge and pre-heat emissions for diesel and different blends of Karanja oil are compared. From the experiment, it is observed that carbon monoxide (CO), hydrocarbon (HC) and smoke emissions are reduced during engine pre-heating and air pre-heating compared to normal condition with respect to increase in time and load at compression ratio 18.  相似文献   

2.
ABSTRACT

In order to improve its performance and emission parameters, higher alcohols are mixed to neat diesel. Higher alcohol (Pentanol) has the capacity for oxygen enrichment during combustion process which put into the catalytic reaction and gets better the combustion process. Pentanol is blended with neat diesel at different measured volumes of 15%, 25% and 35%. Three blended fuels prepared by volume of 85% of diesel and 15% of pentanol (D85P15), 75% of diesel and 25% of Pentanol (D75P25) and 65% of diesel and 35% of Pentanol (D65P35) respectively. Effect of emission and performance parameters have been studied in an unmodified diesel engine propelled with pentanol-diesel blends at various proportions. Pentanol acts as a catalyst (oxidising) and it was helpful in reducing carbon monoxide and hydrocarbon emissions. It is found that a considerable reduction in NOx emission and it also reduces fuel consumption which increases in brake thermal efficiency.  相似文献   

3.
ABSTRACT

The improvement in engine performance and exhaust emissions reduction are the major important issues in developing a more efficient engine. The injection timing is one the major parameters that affect the engine performance and emissions for a diesel engine. The present work focused on characterising the in?uence of injection timing on engine performance and exhaust emissions. This has been critically investigated for B20?+?25?ppm (20% Mimusops Elangi methyl ester-80% diesel fuel?+?25?ppm of TiO2 nanoparticle) additive as alternative fuel. The B20?+25 ppm TiO2 nanoparticle additive produces more HC and CO emission, but reduce NOX emission when injection timing is retarded. Advancement in injection timing for B20?+25?ppm TiO2 nanoparticle additive results in an increase of brake thermal efficiency, decreases brake specific fuel consumption and giving out less HC, CO, smoke emissions but the marginal increase in the NOX emission.  相似文献   

4.
ABSTRACT

In this study, emission level under different load conditions at constant speed was tested for a one-cylinder Compression ignition engine using preheated cnsl oil & diesel blends and ethanol fumigation. According to the emission characteristics and performance of the engine, the temperature of 80°C is considered to be excellent at preheated state. The various blends are [(Preheated CNSL20?+?D80) +E fumigation], [(Preheated CNSL40?+?D60) +E fumigation], [(Preheated CNSL60?+?D40) +E fumigation), (Preheated CNSL80?+?D20) +E fumigation], [(Preheated CNSL100) +E fumigation] are being examined at 80° C. The outputs comprehension is done with pure diesel.  相似文献   

5.
An experimental study is conducted to evaluate the use of rubber seed oil with diesel at a proportion of 20% by volume (RSO20) in a constant speed (1500?rpm) direct injected four-stroke air-cooled single-cylinder compression ignition engine at different injection timings (24°, 27°, 30°, 33° bTDC (before top dead centre)). A series of tests were conducted at various engine load conditions at the rated power of 5.9?kW. The injection pressure was maintained at 200?bar. As a result of investigations, at the full load condition, the brake thermal efficiency of RSO20 at 30° bTDC is high compared with other injection timings and brake energy fuel consumption is increased when advancing injection timing. There is a significant reduction in unburned hydrocarbon emission and carbon monoxide emission, and the oxides of nitrogen emission (NOx) is increased when advancing the injection timing.  相似文献   

6.
Petroleum-based fuels is a finite resource that is rapidly depleting. Consequently, petroleum reserves are not sufficient enough to last many years. In this research, an experimental investigation has been performed to give insight into the potential of biodiesel as an alternative fuel for direct injection (DI) diesel engines. The experimental work has been carried out to estimate the combustion characteristics of a single-cylinder, four-stroke, DI diesel engine fuelled with corn oil methyl ester (COME) and diesel blends. The COME was preheated to temperatures namely 50°C, 70°C and 90°C before it was supplied to the engine. The optimised preheated temperature of 70°C was chosen based on the higher brake thermal efficiency and lower specific fuel consumption. The performance, emission and combustion characteristics are evaluated by running the engine with COME and diesel blends at this preheated temperature. In this paper, the combustion characteristics are only discussed. The combustion characteristics such as ignition delay, maximum rate of pressure, heat release rate, cumulative heat release rate, mass fraction burned and combustion duration of COME methyl ester and diesel were evaluated and compared with neat diesel. The rate of pressure rise and maximum combustion pressure inside the cylinder were high for COME blends compared with neat diesel. The heat release rate of diesel is higher compared with COME blends. The ignition delay and combustion duration are decreased for COME blends compared with neat diesel. The cumulative heat release rate and mass fraction burnt of COME blends are higher than neat diesel.  相似文献   

7.
In this investigation, biogas (BG) was used as an alternative fuel in a single-cylinder, four-stroke, air-cooled, direct injection (DI) diesel engine that was operated on a dual fuel mode. Biogas was produced from a non-edible seed de-oiled cake-pongamia pinnata (Karanja), which was collected from the biodiesel industries. The BG was inducted along with the air in suction of the engine at four different flow rates varying from 0.3?kg/h to 1.2?kg/h in steps of 0.3?kg/h. The investigation results revealed that BG inducted at a flow rate of 0.9?kg/h gives better combustion characteristics of engine behaviour than those of other flows throughout the engine operation. The ignition delay (ID) and combustion duration of the engine run by dual fuel operation at a BG flow rate of 0.9?kg/h were found to be longer by about 2 °CA and 2.9 °CA, respectively, in comparison with diesel at full load. The cylinder peak pressure was found to be overall higher by about 11?bar than that of diesel at full load.  相似文献   

8.
Experimental studies on the Phase Change Material (PCM) storage unit for building ventilation in dry and hot climates were conducted to determine its thermal performance. The PCM unit stored the night time coolness and used it for cooling the hot ambient air during day time. The influence of air flow rate and the inlet air temperature on cold accumulation in PCM during charging process and cold extraction from the PCM during discharging process were analyzed. The air temperatures used for charging of PCM were 20oC, 22oC and 24oC, while during the discharging process, it was at 36oC, 38oC and 40oC. The air flow rates considered for charging of PCM were 4 and 5 m3/hr/kg of PCM. Experimental observations showed that solidification of PCM was more sensitive to the charging air temperature compared to the air flow rate. When the charging air temperature was reduced from 22oC to 20oC, ∼33% less time was needed to completely solidify the PCM. Moreover, when the charging temperature was increased from 22oC to 24oC, ∼52% more time was required by the PCM to complete the solidification process. Changing the air flow rate from 4 m3/hr to 5 m3/hr reduced the solidification time period up to ∼16%.  相似文献   

9.
An experimental investigation to measure the evaporation rates, PSZ-coated engine performance and emissions of radish biodiesel (Methyl Ester of radish oil) and its blends in different volumetric proportions with diesel is presented. The thermo-physical properties of all the fuel blends have been measured and presented. Evaporation rates of neat radish biodiesel, neat diesel and their bends have been measured under slow convective environment of air velocity of 0.2?m/s with a constant temperature of 200°C. Evaporation constants have been determined by using the droplet regression rate data. The neat fuels and fuel blends have been utilised in a test engine with different load conditions to evaluate the performance and emission characteristics of the fuels. From the observed evaporation, performance and emissions characteristics, it can be suggested that a blend of B25–B75 could be optimally used in coated diesel engine settings without any modifications on it.  相似文献   

10.
ABSTRACT

The present paper discusses a comparative study of single- and pilot-injection strategy fuelled with diesel (i.e. Bu00) and 15% of butanol blend (i.e. Bu15). The effects of pilot injection timing (?33° bTDC to ?73° bTDC) and pilot injection fuel quantity (5–20%) with 15% of butanol blend were carried out numerically using CONVERGE CFD Code. The results show that in single-injection strategy, NOx, CO and soot emissions reduce, whereas UBHC emission increases with the addition of butanol content. In pilot-injection strategy, when the first fuel injection timing is advanced, the peak value of heat release rate (HRR) for the first injected fuel reduces, but marginally improves for the main injected fuel. Increasing the first injection fuel quantity, the HRR of the peak value for first injected fuel increases but the HRR of the peak value for second injected fuel reduces. Minimum ISFC was obtained at 10% of pilot injection fuel quantity and ?53° bTDC of pilot injection timing.  相似文献   

11.
This aim of the current study is to evaluate the performance and emission characteristics of pumpkin seed oil with diesel at different blended ratios (B10-CR15, B20-CR15, B10-CR18 and B20-CR18) in a constant speed (1500?rpm) engine. The tests were conducted at various loads of the engine and with specific compression ratios of 15 and 18. The performance and emissions were compared with the different blend ratios and compression ratios. As a result of which the higher compression ratios shows better performance and emission than the lower compression ratio; among them B20-CR18 shows better results such that CO2, HC and CO emissions were reduced and there is a slight increase in NOX value compared to diesel and other blend ratios and also there is an increased brake thermal efficiency for the blend B20-CR18. This shows that the optimum blend is chosen from the results is identified as B20-CR18, which has better performance and emission than other blends and compression ratios.  相似文献   

12.
An experimental investigation of an evacuated tube solar air collector coupled to a latent thermal energy store for generating hot air when no solar radiation is incident was undertaken. Acetamide was used as a phase change material (PCM). The latent thermal energy store was integrated with the manifold of the solar collector and water was used as the working fluid transferring solar gain to the air being heated. The maximum measured temperature differential between the heated air and the ambient air was 37°C and 20.2°C during conditions of incident and non-incident solar radiation, respectively. This occurred using a circular fin configuration at a flow rate of 0.018?kg?s?1. The efficiency at low (0.018?kg?s?1) air flow rates was 0.05–0.50 times less as compared to high (0.035?kg?s?1) air flow rates. This system has advantages over systems using sensible storage as it can be used after sunset due to better heat storing capacity of the PCM.  相似文献   

13.
ABSTRACT

This work investigates the effect of adding Cerium oxide nanoparticles at different proportions (30, 60 and 90?ppm) to Calophyllum inophyllum methyl ester and diesel blends (20% CI methyl ester and 80% diesel) in a four-stroke single-cylinder diesel engine. Addition of nanoparticles is a strategy to reduce emission and to improve the performance of the biodiesel. Modified fuels are introduced into the engine by admitting exhaust gas recirculation (EGR) at a rate of 10% and 20% so as to reduce nitrogen oxide (NOX) emissions from biodiesel and diesel blends. Results revealed a significant reduction in emissions (CO, NOX, HC and Smoke) at a 10% EGR rate. However, brake thermal efficiency is reduced with an increase in brake-specific fuel consumption at higher EGR rates. Hence, it is observed that 10% EGR rate is an effective method to control the emission of biodiesel and diesel blends without compromising much on engine efficiency.  相似文献   

14.
ABSTRACT

The limitations and ramifications of petroleum fuel on the present environmental society raised the necessity of alternative fuel. The physicochemical properties of biodiesel and its ability to reduce emissions have engaged the attention of researchers to prefer biodiesel as a better alternative fuel. A modification in engine parameters is proven to be one of the best techniques to obtain comparable results with diesel. The following study emphasises TSME 20 (20% Tamarind Seed Methyl Ester with 80% diesel) as an alternative fuel and its performance and emission characteristics are deciphered at different injection timings (19°, 23° and 27° bTDC) at different loads. Focusing on the results obtained at full-load condition, considerable improvement in brake thermal efficiency by 3.18% was noticed with the significant reduction in carbon monoxide, hydrocarbon, oxides of nitrogen and smoke by 17.3%, 57.3%, 31.34% and 8.1%, respectively, at retarded injection timing compared to standard injection timing.  相似文献   

15.
ABSTRACT

In today’s world, the usage of internal combustion engines is inevitable. Particularly the diesel engines find their importance more than the petrol engines due to their operating cost. But diesel engines have their demerits in the area of exhaust and power loss. Necessary steps have to be taken in order to effectively use the fuel available. In this technical presentation, we have discussed about the utilisation of six-stroke engines which run on dual fuel. The six-stroke engine’s principle resembles a double-stage compressor. By this way, effective compression is done and the need for turbocharger is completely neglected. We have also considered cylinder’s position in a six-stroke engine. As the lubrication and cooling system needs special attention in the case of opposing-type cylinders, we have formulated a better and simple arrangement in which same power is produced, eradicating the lubrication problems. Also, the pollution (NOx) emitted by the diesel engines is also taken into account. We found the solution in the form of dual-fuel and exhaust gas recirculation system. The combusting temperature of the diesel engine is above 2000°F and this is the prime reason for NOx emission. So an alternative fuel which can be combusted below the level of diesel should be used. Moreover, the availability and production cost must be taken into consideration. We found ethanol as a better alternative for diesel. The cold starting of the engine is made easier using a glow plug, which is used to preheat the charge coming inside the combustion chamber.  相似文献   

16.
Stringent emission regulations and health awareness about air pollution have led researchers to find alternative means of minimising emissions in diesel engines. In this article, the influence of oxygen enrichment is discussed to determine the effect on diesel engine performance, emission characteristics and combustion characteristics. Normal diesel and oxygen-enriched diesel are used in this experiment. The increase in oxygen concentration led to complete combustion, producing higher thermal efficiency and low harmful emissions. From the results, it is noted that oxygen-enriched diesel fuel showed reduction of CO, HC and smoke emissions, while NOx emission increased.

Abbreviations/Nomenclature DI: direct injection; NOx: oxides of nitrogen; O2: oxygen; HC: hydrocarbon; PM: particulate matters; CO: carbon monoxide; CO2: carbon dioxide  相似文献   


17.
Biodiesel is a promising renewable alternative fuel for diesel. The need of biodiesel fuels for the diesel engines is to restrict the dependency on the fossil fuels in context to the world energy oil crisis. The objective of this article is to investigate the performance and emission characteristics of a CI engine with diesel and blends of canola biodiesel Emulsion at 200, 220 and 240?bar. The fuel injection system in a diesel engine is to achieve a high degree of atomisation for better penetration of fuel in order to utilise the full air charge and to promote the evaporation in a very short time and to achieve higher combustion efficiency. Emulsified fuels showed an improvement in brake thermal efficiency of 28.8% at 240?bar accompanied by the drastic reduction in NOx at 200?bar.  相似文献   

18.
Experiments were conducted on a 4-cylinder direct-injection diesel engine with fumigation methanol injected into the air intake of each cylinder. The fumigation methanol was injected to top up 10%, 20% and 30% of the power output under different engine operating conditions. The effects of fumigation methanol on engine performance, gaseous emissions and particulate emission were investigated. The experimental results show that there is a decrease in the brake thermal efficiency when fumigation methanol is applied, except at the highest load of 0.67 MPa. At low loads, the brake thermal efficiency decreases with increase in fumigation methanol; but at high loads, it increases with increase in fumigation methanol. The fumigation method results in a significant increase in hydrocarbon (HC), carbon monoxide (CO), and nitrogen dioxide (NO(2)) emissions. The concentration of nitrogen oxides (NOx) is significantly reduced except at close to full load condition. There is also a reduction in the smoke opacity and the particulate matter (PM) mass concentration. For the submicron particles, the total number of particles decreases at low and medium loads but increases at high loads. In all cases, there is a shift of the particles towards smaller geometrical mean diameter, especially at high loads. The increase in nano-sized particles and the increase in NO(2) emission could have serious impact on human health.  相似文献   

19.
ABSTRACT

Bioalcohols have recently become one of the promising alternate fuels. Lower alcohols exhibit some problems like phase separation, stability issues, storage problems, corrosion etc. Hence, the addition of higher alcohols is regarded least-problematic and the concept of using higher alcohols as fuel blends is relatively new. In this article, the effects of the addition of higher alcohol (1-pentanol) on engine performance and emission characteristics are discussed. Two reference fuels (diesel and biodiesel derived from waste cooking oil) and two test fuels (blends of 20% of 1-pentanol and 80% of either diesel or biodiesel) are tested in a single cylinder compression ignition diesel engine for six load conditions (0, 4, 8, 12, 16, and 20?kg) at a constant speed of 1200?rpm. The engine performance and emission characteristics are determined and discussed.  相似文献   

20.
ABSTRACT

Injection timing (IT) is a vital factor among different injection parameters which governs the emissions and performance factors of the engine. This work portrays the effect of IT on cerium oxide nanoparticle doped Waste Cooking Palm Oil biodiesel and diesel blends. The doping is made at 30, 60 and 90?ppm. The modified fuels are introduced in reducing IT of 19°, 21° and 23°bTDC. 1500?rpm engine is made use in this study. Results revealed a significant reduction in emissions (CO, NOX, HC and Smoke) at IT?=?23°bTDC. Furthermore, performance (BSFC, BTE) is improved for fuel blends at IT?=?23°bTDC.  相似文献   

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