Experimental Investigation Of Combustion Research Articles

Experimental investigation of combustion and ash deposition characteristics of coal-NH3 cofiring in a 200 kW furnace

The coal-NH3 co-firing experiment was conducted in a 200 kW one-dimensional furnace to study the flue gas emission characteristics and ash deposition characteristics under different ammonia co-firing ratios. As ammonia is a carbon-free fuel, CO2 shows a decreasing trend, while H2O gradually increases with the increase of ammonia co-firing ratio. With the increase of ammonia co-firing ratio, the proportion of unburned carbon increases slightly. Compared with the ammonia in flue gas, the ammonia attached to ash is the main reason for ammonia slip. The total ammonia slip rate of the three co-firing ratio conditions is 0.26% (5% NH3), 0.29% (10% NH3) and 0.67% (20% NH3), respectively. The NOx emission reaches the maximum of 349.05 ppm when the ammonia co-firing ratio is 10%, then decreases as the ratio increase to 20%. Ammonia co-firing does not change the composition of ash particles but has a certain deterioration of heat transfer of heat exchange surface in high temperature zone of furnace. This is related to the adhesion of ammonia on the surface of fly ash and the reduction of the size of fly ash.

EXPERIMENTAL INVESTIGATION OF COMBUSTION AND SOOT FORMATION CHARACTERISTICS OF IMPINGING BIODIESEL-BLENDED SPRAYS IN CONSTANT VOLUME CHAMBER

EXPERIMENTAL INVESTIGATION OF COMBUSTION AND SOOT FORMATION CHARACTERISTICS OF IMPINGING BIODIESEL-BLENDED SPRAYS IN CONSTANT VOLUME CHAMBER

Experimental investigation of combustion, performance and emission characteristics of a diesel engine fuelled with diesel–biodiesel–alcohol blends

The purpose of this study is to investigate the impacts of diesel–biodiesel–alcohol blends on the combustion, performance and emissions characteristics of a single-cylinder diesel engine. Tests were conducted at different engine speeds of 1750, 2250, 2750 and 3250 rpm and under full load. In this study, different fuels [called as reference diesel (D100), 20 vol% cottonseed methyl ester (D80C20), 10 vol% ethanol (D90E10) and finally the ternary type of their derivations (D70C20E10)], were used. The experimental results showed that the highest reduction values were observed on CO emission by 42%, 30% and 8% for the D90E10, D70C20E10 and D80C20 fuels, respectively. These reductions for HC emission were achieved as 40%, 31% and 23% for the D90E10, D70C20E10 and D80C20, respectively. On the other hand, the reductions of NOx and CO2 emissions were not sharp and varied between 2–7%. Besides the reductions on the exhaust emissions, biodiesel–ethanol blend presented better results in terms of HRRmax and CPmax than using biodiesel alone. Additionally, ignition delay of the biodiesel blends was longer than that of D100 fuel owing to their low cetane numbers. Combustion duration was shortened with the increment in engine speed because the turbulence increased in the combustion chamber at high engine speed. This case also improved the homogeneity of test fuels and increased the quality of the combustion process. As a consequence, this paper clearly reported that it is possible to achieve fewer emissions, the highest CPmax values with the presence of ethanol in biodiesel fuels rather than using biodiesel alone for diesel engines.

Experimental investigation of combustion and particle emissions under different combustion modes on a heavy-duty diesel engine fueled by diesel/gasoline/diesel from direct coal liquefaction

In an effort to contribute in further reducing pollution and fuel consumption, the effects of various combustion modes on the combustion process and emissions were investigated on a modified single cylinder from a six-cylinder engine using diesel, gasoline, and diesel from direct coal liquefaction (DDCL). The engine was run at 1000 r/min with an indicated mean effective pressure (IMEP) of 0.7 MPa. Additionally, we experimentally evaluated the impact of exhaust gas recirculation (EGR) and did comparisons among the tested fuels. Gasoline was injected into the intake port to form a homogeneous mixture and compression ignition, which led to homogeneous charge compression ignition (HCCI). Diesel was injected near top dead center (TDC), which was dominated by diffused combustion depending on the mixing rate of diesel and air. DDCL was also injected near TDC. In comparison with diesel, DDCL has a longer ignition delay (ID) than diesel due to low cetane number and high volatility. It also had a heat release rate between that of gasoline and diesel. Among the tested fuels, gasoline displayed the highest gross indicated thermal efficiency, followed by DDCL, and then diesel. Moreover, emission test results showed that gasoline had the lowest NOx and soot emissions, but had the highest CO and HC emissions. Different particle modes were present under different EGR conditions. For instance, at an EGR ratio lower than 20%, the particles of the tested fuels were composed mainly of nucleation-mode particles. When the EGR ratio was higher than 20%, the particles of DDCL and diesel were of accumulation-mode, whereas those of gasoline were of small-diameter nucleation-mode.

Experimental Investigations of Combustion: (95 WT.-%) HAN–Water Solution with High-SSA Activated Carbons

ABSTRACTThe thermal decomposition of hydroxylamine nitrate (HAN) 95% water solution, a “green” alternative of fuel/oxidizer formulation to hydrazine nitrate, as a rocket propellant in the presence of the high-specific surface area (SSA)-activated carbons was investigated. It was shown that the linear burning rate increased for the system of HAN 95% water solution admixed with activated carbons compared to that of the 95% water solution HAN alone. Also, decomposition of the mixture (HAN spiked with rice husk (RH)-derived activated carbons by 1 mass %) was monitored by electron ionization–mass spectrometry (EI–MS) at different heating rates (from 16 to 128 K/min). EI MS analysis of the formation of major gas products (NO, NO2 and N2O) at the HAN decomposition in presence carbon particles shown various results.

Experimental investigation of Combustion, Performance and Emission in single cylinder diesel engine operated on blends of diesel and waste cooking oil

We all are aware with the limited amount of energy and there resources. Today the agriculture sector needs good amount of energy, mainly energy from CI engine. As the consumption of energy increase the demand of energy also increases, mainly in petroleum sector. Today 90 % of the total demand is full filled by the fossil fuels. The petroleum sector needs some alternative fuels to reach the demand. This research straightly focused on the use of waist cooking oil This concept also needs to aware with the consequences of reusing the WCO domestically and in restaurants. whenever the demand of energy needed we searches about alternative fuels so to complete the research for a alternative fuel we have to learn about fossil fuels ,exhaust emissions ,global warming etc. Here we used blends of waist cooking oil and diesel oil which are prepared by volume name as B5 using 5% of WCO and B10 comprise 10% WCO. The combustion , performance and emission properties are studied experimentally by combustion of different blends at different loads. It has to observed that in performance characteristic Mechanical efficiency is more for B10 when compare with B5 and conventional Diesel. When the load is increases fuel consumptions shows a considerable fall while it is noticeable that CO emission trend decreases and NOx increases after increasing some loads and HC are also indicate a down fall trend ,on other hand CO2 emissions shows less affected.

Experimental Investigation of Combustion and Emission Characteristics of Variable Compression Ratio Compression Ignition Engine Using Cotton Seed Oil Biodiesel Blends

<p>The increasing demand of petroleum and its availability is inversely to each other. This gives the new area to researcher to find out the solution to this problem. This problem is also concern with socioeconomically issue; the solution should be acceptable to each one. The alternative fuels derived from vegetable are the keen area of research, which are economical, environment friendly and easily available. In this paper the cottonseed oil biodiesel blends is considered as fuel for variable compression ratio diesel engine. The combustion characteristics in terms of mass of fraction burnt is investigated for different compression ratio. The emission characteristics are also investigated in comparison with petroleum diesel without any modification in engine. The results are compatible with petroleum diesel.</p>

Experimental investigation of combustion, emissions and thermal balance of secondary butyl alcohol-gasoline blends in a spark ignition engine

An experimental investigation of butanol as an alternative fuel was conducted. A four-cylinder, four-stroke gasoline engine was used to investigate the engine combustion emissions and thermal balance characteristics using 2-butanol–gasoline blended fuels at 50% throttle wide open. In this experimental study, the gasoline engine was tested at 2-butanol–gasoline percentage volume ratios of 5:95 (GBu5), 10:90 (GBu10) and 15:85 (GBu15) of gasoline to butanol, respectively. Combustion analysis results showed that 2-butanol–gasoline blends have a lower in-cylinder pressure, rate of pressure rise and rate of heat release. However, as the 2-butanol addition increases in the blended fuels, increasing trends of in-cylinder pressure, rate of pressure rise and rate of heat release are observed, but it is still lower than G100 fuels. Moreover, even 5%, 10% and 15% additions of 2-butanol in the gasoline fuels improve the COV of IMEP by 3.7, 3.46 and 3.26, respectively, which indicates that the presence of 2-butanol stabilises the combustion process. Comparative analysis of the experimental results by exhaust emissions produced an average of 7.1%, 13.7%, and 19.8% lower NOx for GBu5, GBu10 and GBu15, respectively, over the speed range of 1000–4000 RPM. Other emission contents indicate lower CO and HC but higher CO2 from 2500 to 4000RPM for the blended fuels with regard to G100. The thermal balance analysis mainly exhibits an improvement in effective power, cooling energy and exhaust energy by average differences of 3.3%, 0.8% and 2.3% for GBu15 compared with G100.

Experimental investigations of combustion, performance and emission characteristics of a hydrogen enriched natural gas fuelled prototype spark ignition engine

In this study, spark ignition of hydrogen enriched natural gas (HCNG), a fast emerging alternative gaseous fuel, was experimentally investigated in a suitably modified single cylinder spark ignition (SI) engine. Port fuel injection of the HCNG engine using a high volume flow rate solenoid injector, controlled by a customized injector control unit and electronic control unit (ECU) was done and the fuel injection timings and duration were controlled for each load. Fuels with different H/C ratios in the final HCNG mixture were investigated for their engine performance, emissions and combustion characteristics. Engine investigations were carried out at constant engine speed of 1500rpm for different H/C ratios (4, 4.22, 4.5, 4.85, 5.33 and ∞). Spark timing was kept constant (32° bTDC) for all test blends. Relative air–fuel ratio (RAFR) was kept constant for all loads during the experiments in order to avoid misfire at lower engine load. Hydrogen exhibited higher pressure peak (Pmax) but lower maximum brake torque (MBT) compared to other test fuels due to lower knocking limit. Brake thermal efficiency (BTE) was superior for test fuel with H/C: 4.5. NOx emissions were higher for test fuel with H/C: 4.22 and relatively lower for hydrogen compared to baseline natural gas.

Fe Reduction by Carbon during Self-Propagating High-Temperature Synthesis of Fe-TiC Composite

The results of experimental investigations of combustion of the powder mixture of titanium, carbon, and ferrous oxide (III) are shown in this paper. Iron reduction by carbon is an endothermic reaction and proceeds in combustion wave of SHS due to the heat of high-exothermic reaction of TiC formation. It was found that it is impossible to initiate the combustion process with (Fe2O3+C) content of 50 wt. % or more of the initial charge composition. With not very high content of (Fe2O3+C), only Fe and TiC are found in the reaction products. When approaching its content to 50 wt. %, also С and FeO impurity phases are detected. The SHS product is a cake of separate granules of Fe-TiC with the granule size of 100-500 μm.

Experimental investigation of combustion, performance and emission characteristics of a modified piston

In this investigation, the combustion, performance and emission characteristics of a diesel engine powered with Modified piston (MP) are studied. Engine tests have been carried out using conventional diesel and 20% blend of adelfa biodiesel [A20]. Results obtained from renewable fuel A20 in conventional engine have shown reduction in brake thermal efficiency that may be ascribed to poor air fuel mixing characteristics and higher viscosity of the fuel. This prompted the research towards improvement of turbulence for better air fuel mixing through a novel modification of the piston. The engine with modified piston has shown improved Brake thermal efficiency (BTE), Combustion characteristics and reduced hydrocarbon (HC), carbon mono oxide (CO), and smoke emissions. Nevertheless, the nitrogen oxide emissions have been found to be slightly higher than the conventional unmodified engine.

Combustion and Emission Investigation of Diesel Fuel and Kerosene Blends

This study presents experimental investigation of combustion of diesel fuel, kerosene and their blends. The objective of this study is to determine the combustion performance and gas emission of diesel fuel, kerosene and various mixtures of diesel fuel and kerosene in a horizontally positioned cylindrical furnace. Heat was removed from the system by the use of water around a jacket of the combustion unit. The combustion unit is capable of burning most types of liquid and gaseous hydrocarbon fuels. Results on combustion performance and gas emissions are presented for a wide range of air fuel equivalence ratios. The results of exhaust gas analyses of carbon monoxide, carbon dioxide and oxygen are presented. Combustion efficiency and the effect of blending of fuels on its performance are also presented. In general, some improvements in exhaust gas emission and combustion efficiency were obtained upon using mixtures of fuels. The best results were obtained when a fuel blend of 75% kerosene and 25% diesel was prepared and burned in the unit.

Experimental Investigation of Combustion and Emission Characteristics for Internal Combustion Rankine Cycle Engine under Different Water Injection Laws

This paper discusses a novel oxyfuel combustion method named internal combustion rankine cycle (ICRC) used in reciprocating engines. Water is heated up through heat exchanger by exhaust gas and engine coolant, and then injected into the cylinder during the combustion to control the oxyfuel combustion temperature and reaction rate. Moreover, evaporation of the water mist increases the mass of working fluid so indicated thermal efficiency of the cycle is enhanced. This study investigates combustion and emission characteristics of ICRC engine under different water injection laws. The results show that indicated work and thermal efficiency increases significantly due to water injection process. The properly increase of injection duration and pressure improve IMEP (Indicated mean effective pressure) and thermal efficiency. Engine stability becomes better under lower water injection pressure and less injection duration. Less water injection duration and better injection atomization causes lower HC emissions, while NOx emissions stay under low level.

Experimental investigations of combustion, performance and emission characterization of biodiesel fuelled HCCI engine using external mixture formation technique

In the present research, effect of biodiesel content on homogeneous charge compression ignition (HCCI) engine combustion, performance and emission characteristics has been investigated experimentally. Experiments were performed in a modified two cylinder engine, in which, one cylinder was operated in HCCI mode while other was operated in conventional CI mode. HCCI engine can be operated with a wide variety of fuels starting from mineral diesel to various blends of biodiesel (B20 and B40). The basic requirement of the HCCI engines is homogeneous mixing of fuel and air, which is done by using port fuel injection strategy in this study. An external device was used for fuel vaporization and mixture formation. For controlling HCCI combustion, different EGR conditions (0%, 15% and 30%) were also applied. In the experiments, combustion results were found to be more stable for biodiesel HCCI compared to diesel HCCI due to lower rate of heat release (RoHR) for biodiesel. A reduction in power output and an increase in ISFC were observed upon increasing the biodiesel content in the test fuel. A small increase in CO, HC and smoke emissions was observed with increasing biodiesel content due to slower evaporation rate of biodiesel. A significant reduction in NOx emissions was also observed with for biodiesel blends.

Experimental investigations of combustion and emission characteristics of rapeseed oil–diesel blends in a two cylinder agricultural diesel engine

The main objective of this paper was to study the performance, emissions and combustion characteristics of a diesel engine using rapeseed oil–diesel blends. The main fuel properties of rapeseed oil (RSO) were investigated and compared with that of diesel fuel. The experimental results showed that the viscosity and density of the blends were decreased and approached to that of diesel fuel when RSO volume fraction was less than 20%. At low engine loads, the start of combustion for the blends was almost similar to that for diesel fuel, but the peak cylinder pressure and heat release rate were higher. At high engine loads, the start of combustion for the blends was slightly earlier than that for diesel fuel, but the peak cylinder pressure and heat release rate were identical. For the blends, there was slightly higher brake specific fuel consumptions (BSFC) and brake specific energy consumptions (BSEC) at low engine loads. Smoke emission was higher at low engine loads, but lower at high engine loads. Nitrogen oxide (NOx) emission was observed slightly lower at low engine loads and almost identical at high engine loads. Carbon monoxide (CO) and hydrocarbon (HC) emission were higher under all range of engine loads for the blends.

Experimental Investigation of Emissions from Biodiesel

Biodiesel from waste cooking oil offers sustainable alternative to diesel. This paper presents an experimental investigation of combustion of biodiesel derived from waste cooking oil to study the characteristics of biodiesel emissions compared to diesel. The combustion of neat biodiesel and biodiesel blended in different ratios with diesel was investigated using continuous combustion rig. The temperature of combustion gases, emissions of un-burnt HC and NO for different airflow rates were evaluated. Differences in the chemical composition between biodiesel and diesel result in different mechanisms of NO and HC formation. The results provide insight into combustion and emission from biodiesel. It was observed that the combustion gas temperature (CGT), adiabatic flame temperature, unburned hydrocarbon (HC) and carbon monoxide (CO) decrease, while nitrogen oxides (NOx) increases when the proportion of biodiesel is increased in the blend. Combustion of biodiesel blends for 2% excess O2 shows the best compromise between the reduction in unburned HC and the lowest increase in NOx. It can be concluded that biodiesel made from waste cooking oil has potential to use as alternative to diesel fuel in internal combustion engine and has significant environmental benefits compare to diesel.

Early Flame Development in the Combustion of Droplet and Vapour Mixtures

Experimental investigations of combustion of droplet and vapour mixtures under quiescent condition have been conducted in a closed combustion vessel. Droplet and vapour mixtures or aerosol mixtures were generated by expansion of iso-octane gaseous pre-mixture to produce a homogeneously distributed suspension of fuel droplets. The aerosol mixtures were ignited centrally in the combustion vessel and the flame development was recorded by schlieren photography. The effect of fuel droplets in the early stage of flame propagation was investigated by comparing the flame structure and flame speed of gaseous mixtures at identical conditions. Comparison between gaseous and aerosol flame have shown quantitatively that the presence of fuel droplets causes earlier onset of instabilities and cellularity than for gaseous flames, particularly at rich conditions. This difference was shown to be a function of droplet size and overall equivalence ratio. It is suggested that these factors lead to vary the local equivalence ratio which increases the initial burning rate of lean aerosols, but decreases that of rich ones.

Numerical and Experimental Investigation of Combustion and Knock in a Dual Fuel Gas/Diesel Compression Ignition Engine

Conventional compression ignition engines can easily be converted to a dual fuel mode of operation using natural gas as main fuel and diesel oil injection as pilot to initiate the combustion. At the same time, it is possible to increase the output power by increasing the diesel oil percentage. A detailed performance and combustion characteristic analysis of a heavy duty diesel engine has been studied in dual fuel mode of operation where natural gas is used as the main fuel and diesel oil as pilot. The influence of intake pressure and temperature on knock occurrence and the effects of initial swirl ratio on heat release rate, temperature-pressure and emission levels have been investigated in this study. It is shown that an increase in the initial swirl ratio lengthens the delay period for auto-ignition and extends the combustion period while it reduces NOx. There is an optimum value of the initial swirl ratio for a certain mixture intake temperature and pressure conditions that can achieve high thermal efficiency and low NOxemissions while decreases the tendency to knock. Simultaneous increase of intake pressure and initial swirl ratio could be the solution to power loss and knock in dual fuel engine.

Experimental investigation of combustion and heat transfer in a direct-injection spark ignition engine via instantaneous combustion chamber surface temperature measurements

An experimental study was performed to provide the combustion and in-cylinder heat transfer characteristics resulting from different injection strategies in a direct-injection spark ignition (DISI) engine. Fast-response thermocouples were embedded in the piston top and cylinder head surface to measure the instantaneous combustion chamber surface temperature and heat flux, thus providing critical information about the combustion characteristics and a thorough understanding of the heat transfer process. Two distinctive operating modes, homogeneous and stratified, were considered and their effect on combustion and heat transfer in a DISI engine was investigated. The stratified operating mode yielded significantly higher spatial variations of heat flux than the homogeneous mode. This behaviour is directly caused by the main features of stratified combustion, i.e. vigorous burning of a close-to-stoichiometric mixture near the spark, and a cool, extremely lean mixture at the periphery. The cooling effect of the spray impinging on the piston surface when the fuel is injected late in compression could be detected too. The local phenomena change with varying speed and injection parameters. Comparison between the calculated global heat fluxes and measured local heat fluxes were performed in order to assess the behaviour of classic heat transfer models. Comparisons between the global and local heat fluxes provide additional insight into spatial variations, as well as indications about the suitability of different classic models for investigations of the heat transfer aspect of DISI engines. Special consideration is required when applying classic heat transfer correlations to stratified DISI operation as heat flux values are lower by more than 30 per cent when compared with homogeneous operation of the same engine at the same load.

05/01983 Experimental investigation of combustion in porous heating burners

05/01983 Experimental investigation of combustion in porous heating burners