Simplified Method for Fuel Quality Prediction

2005 ◽  
Author(s):  
Aravind Sivaraman ◽  
Sridhar Ranganathan ◽  
Shashank Tangirala ◽  
G. Lakshmi Narayana Rao
Keyword(s):  
Diesel Engine ◽  
Standard Test ◽  
Operating Conditions ◽  
Exhaust Gas ◽  
Test Rig ◽  
Single Cylinder ◽  
Fuel Ratio ◽  
Test Conditions ◽  
Quality Rating

The objective of this work is to compare the quality of various diesel fuels using a normal engine and carrying out the test under the actual operating conditions of the engine, unlike the conventional test methods that uses standard test conditions. The standard test conditions involve the running of the diesel engine test rig at a speed of around 800 rpm, which is not the condition when the fuel is actually being used, as the operational speed of commercial engines is around 1500–2000 rpm. Also the non-engine based quality rating methods are not economically liable and are inaccurate as they depend too much on the chemical nature of the fuel. So, the objective of this work is to develop a generalized quality rating procedure with less number of parameters, with a simpler and cheaper method compared to other available methods. A single cylinder diesel engine was used to study the ignition quality of various reference fuels of known Cetane numbers. A relatively simple and compact setup was used, by modifying the existing test rig. The inlet manifold was incorporated with an airflow control valve so that the quantity of air let into the cylinder can be varied. The exhaust gas manifold was modified to enable easier observation of the exhaust gas. The single cylinder diesel engine was made to run at two distinct conditions, namely, the normal and white-puff / critical condition, with the reference fuels of known cetane numbers. The quantity of air available for the fuel to combust is the only difference between the two conditions. The air-fuel ratio of each fuel under both the conditions was continuously monitored. A correlation was developed between the critical air-fuel ratios and the corresponding Cetane numbers. From this correlation, a test fuel can be rated easily by finding the air-fuel ratio, by running it in the same engine at an identical load, at an instant when the “white puff” is observed.

New Modular Test Rig for Unsteady Performance Assessment of Automotive Turbocharger Turbines

2017 ◽  
Author(s):  
Paul Lyttek ◽  
Harald Roclawski ◽  
Martin Böhle ◽  
Marc Gugau
Keyword(s):  
Gas Flow ◽  
Measurement Techniques ◽  
Basic Research ◽  
Standard Test ◽  
Operating Conditions ◽  
Test Facility ◽  
Exhaust Gas ◽  
Special Device ◽  
Test Rig ◽  
Inflow Conditions

Standard test rigs for basic research on turbochargers usually do not provide the capability of periodically changing, instantaneous process values, which are characteristic for the real application of these turbines. The challenge of testing the performance potential of turbocharger turbines under pulsating inflow conditions is mainly originated by the complex compatibility of two main issues that need to be implemented at a test facility: Firstly, a special device is required that reproducibly provides real engine-like exhaust gas pulsations with some variability representing different engine operating conditions. Secondly, appropriate real time measurement techniques for all significant transient values are required to measure both, instantaneous turbine inflow conditions and turbine power output. This paper presents a new developed test rig that enables a preferably high overlap between the above mentioned supply of approximately real engine exhaust gas conditions and the fundamental and scientifically based attempt of unsteady gas flow examinations.

Simulation of a Single Cylinder Diesel Engine Under Cold Start Conditions Using Simulink

2000 ◽  
Vol 123 (1) ◽  
pp. 117-124 ◽  
Author(s):  
H.-Q. Liu ◽  
N. G. Chalhoub ◽  
N. Henein
Keyword(s):  
Diesel Engine ◽  
Direct Injection ◽  
Cold Start ◽  
Operating Conditions ◽  
Combustion Model ◽  
Nonlinear Dynamic Model ◽  
Single Cylinder ◽  
Engine Model ◽  
Simulink Model ◽  
Engine Components

A nonlinear dynamic model is developed in this study to simulate the overall performance of a naturally aspirated, single cylinder, four-stroke, direct injection diesel engine under cold start and fully warmed-up conditions. The model considers the filling and emptying processes of the cylinder, blowby, intake, and exhaust manifolds. A single zone combustion model is implemented and the heat transfer in the cylinder, intake, and exhaust manifolds are accounted for. Moreover, the derivations include the dynamics of the crank-slider mechanism and employ an empirical model to estimate the instantaneous frictional losses in different engine components. The formulation is coded in modular form whereby each module, which represents a single process in the engine, is introduced as a single block in an overall Simulink engine model. The numerical accuracy of the Simulink model is verified by comparing its results to those generated by integrating the engine formulation using IMSL stiff integration routines. The engine model is validated by the close match between the predicted and measured cylinder gas pressure and engine instantaneous speed under motoring, steady-state, and transient cold start operating conditions.

Effect of Fuel Injection Strategy on DPF Regeneration in Single Cylinder Diesel Engine

2015 ◽  
Author(s):  
Sungjun Yoon ◽  
Hongsuk Kim ◽  
Daesik Kim ◽  
Sungwook Park
Keyword(s):  
Diesel Engine ◽  
Fuel Injection ◽  
Operating Conditions ◽  
Experimental Results ◽  
Exhaust Gas ◽  
Post Injection ◽  
Gas Temperature ◽  
Injection Strategy ◽  
Dpf Regeneration ◽  
Exhaust Gas Temperature

Stringent emission regulations (e.g., Euro-6) force automotive manufacturers to equip DPF (diesel particulate filter) on diesel cars. Generally, post injection is used as a method to regenerate DPF. However, it is known that post injection deteriorates specific fuel consumption and causes oil dilution for some operating conditions. Thus, an injection strategy for regeneration becomes one of key technologies for diesel powertrain equipped with a DPF. This paper presents correlations between fuel injection strategy and exhaust gas temperature for DPF regeneration. Experimental apparatus consists of a single cylinder diesel engine, a DC dynamometer, an emission test bench, and an engine control system. In the present study, post injection timing covers from 40 deg aTDC to 110 deg aTDC and double post injection was considered. In addition, effects of injection pressures were investigated. The engine load was varied from low-load to mid-load and fuel amount of post injection was increased up to 10mg/stk. Oil dilution during fuel injection and combustion processes were estimated by diesel loss measured by comparing two global equivalences ratios; one is measured from Lambda sensor installed at exhaust port, the other one is estimated from intake air mass and injected fuel mass. In the present study, the differences in global equivalence ratios were mainly caused from oil dilution during post injection. The experimental results of the present study suggest an optimal engine operating conditions including fuel injection strategy to get appropriate exhaust gas temperature for DPF regeneration. Experimental results of exhaust gas temperature distributions for various engine operating conditions were summarized. In addition, it was revealed that amounts of oil dilution were reduced by splitting post injection (i.e., double post injection). Effects of injection pressure on exhaust gas temperature were dependent on combustion phasing and injection strategies.

Effect of Operating Conditions on the Particulates from a Single Cylinder Diesel Engine

1983 ◽  
Author(s):  
Henry Richard ◽  
Deighton Simpson ◽  
Barbara Mary Andon ◽  
William George Thilly ◽  
Joe Merrill Rife
Keyword(s):  
Diesel Engine ◽  
Operating Conditions ◽  
Single Cylinder

scholarly journals Cyclic NO2:NOx ratio from a diesel engine undergoing transient load steps

2019 ◽  
Vol 22 (1) ◽  
pp. 284-294 ◽  
Author(s):  
FCP Leach ◽  
MH Davy ◽  
MS Peckham
Keyword(s):  
Diesel Engine ◽  
High Speed ◽  
Exhaust Gas Recirculation ◽  
Operating Conditions ◽  
Formation Mechanisms ◽  
Exhaust Gas ◽  
Work Cycle ◽  
Wide Range ◽  
Gas Recirculation ◽  
Aftertreatment Systems

As the control of real driving emissions continues to increase in importance, the importance of understanding emission formation mechanisms during engine transients similarly increases. Knowledge of the NO2/NOx ratio emitted from a diesel engine is necessary, particularly for ensuring optimum performance of NOx aftertreatment systems. In this work, cycle-to-cycle NO and NOx emissions have been measured using a Cambustion CLD500, and the cyclic NO2/NOx ratio calculated as a high-speed light-duty diesel engine undergoes transient steps in load, while all other engine parameters are held constant across a wide range of operating conditions with and without exhaust gas recirculation. The results show that changes in NO and NOx, and hence NO2/NOx ratio, are instantaneous upon a step change in engine load. NO2/NOx ratios have been observed in line with previously reported results, although at the lightest engine loads and at high levels of exhaust gas recirculation, higher levels of NO2 than have been previously reported in the literature are observed.

scholarly journals Design and Testing of a 10KW Steam Turbine for Steam Turbochargers

1985 ◽  
Author(s):  
M. Rautenberg ◽  
M. Malobabic ◽  
A. Mobarak ◽  
M. Abdel Kader
Keyword(s):  
Waste Heat ◽  
Rankine Cycle ◽  
Operating Conditions ◽  
Experimental Investigations ◽  
Exhaust Gas ◽  
Test Rig ◽  
Pelton Turbine ◽  
Partial Admission ◽  
Turbine Design ◽  
Design And Testing

A Clausius-Rankine-cycle has been proposed to recover waste heat from a piston engine. This waste heat is then used to supercharge the cylinders by means of a steam turbocharger. The advantage of using this steam turbocharger system is to avoid the losses due to the engine back pressure which accompany the use of the conventional exhaust gas turbocharger. The mass flow rate of turbines for steam turbochargers in the range from 1 to 10 kW is about 0.03 to 0.08 kg/s. This implies a special turbine design, characterised by partial admission and supersonic flow, which unfortunately leads to low turbine efficiencies. A small Pelton turbine for steam has been designed and produced. The turbine is connected to the radial compressor of a conventional exhaust gas turbocharger which works, in this case, as a brake to dissipate the generated turbine power. A special test rig has been built to carry out the experimental investigations on the proposed Pelton turbine. The test rig is supplied with superheated steam from the University’s power plant. Two different rotors for this Pelton turbine have been tested under the same operating conditions (rotor 2 see Fig. 1). Some experimental test results of a special Pelton turbine are presented and discussed in this report.

Impact of Intake Induced Swirl on Combustion and Emissions on a Single Cylinder Diesel Engine

2016 ◽  
Author(s):  
Eduardo Barrientos ◽  
Ivan Bortel ◽  
Michal Takats ◽  
Jiri Vavra
Keyword(s):  
Diesel Engine ◽  
Heat Release ◽  
Operating Conditions ◽  
Common Rail ◽  
Injection System ◽  
Nox Emissions ◽  
Cylinder Pressure ◽  
Swirl Ratio ◽  
Single Cylinder ◽  
Optimal Values

Engine induced swirl improves mixing of fuel and air and at optimal values accelerates burn, improves the combustion stability and can decrease particulate matter (PM). However, swirl increases convective heat loss and cylinder charge loss and could increase nitrogen oxides (NOx) emissions. High intensity of swirl could impede flame development and increases emissions of total hydrocarbons (THC) and carbon monoxide (CO). Therefore, careful and smart selection of optimal swirl values is paramount in order to obtain beneficial impact on combustion and emissions performance. This study is conducted on a 0.5L single cylinder research engine with common rail (CR) diesel injection system, with parameters corresponding to modern engines of passenger cars. The engine has three separate ports in the cylinder head. The change of swirl ratio is defined by closing appropriate ports. There are three levels of swirl ratio under study — 1.7, 2.9 and 4.5, corresponding to low, medium and high swirl levels respectively. This study highlights the influence of intake induced swirl on combustion parameters and emissions. Assessed combustion parameters are, among others, heat release rate, cylinder pressure rise and indicated mean effective pressure. Assessed emissions are standard gaseous emissions and smoke, with emphasis on PM emissions. An engine speed of 1500 rpm was selected, which well represents common driving conditions of this engine size. Various common rail pressures are used at ambient inlet manifold pressure (without boost pressure) and at 1 bar boosted pressure mode. It is found that when the swirl level is increased, the faster heat release during the premixed combustion and during early diffusion-controlled combustion causes a quick increase in both in-cylinder pressure and temperature, thus promoting the formation of NOx. However, since swirl enhances mixing and potentially produces a leaning effect, PM formation is reduced in general. However, maximum peak temperature is lower for high swirl ratio and boosted modes due to the increase of heat transfer into cylinder walls. Furthermore, it is necessary to find optimal values of common rail pressures and swirl ratio. Too much mixing allows increase on PM, THC and CO emissions without decrease on NOx emissions in general. Common rail injection system provides enough energy to achieve good mixing during all the injection time in the cases of supercharged modes and high common rail pressure modes. Positive influence of swirl ratio is found at lower boost pressures, lower revolution levels and at lower engine loads. The results obtained here help providing a better understanding on the swirl effects on diesel engine combustion and exhaust emissions over a range of engine operating conditions, with the ultimate goal of finding optimal values of swirl operation.

Optical Patternation of Gas Turbine Fuel Sprays During Simulated Engine Operating Conditions

2009 ◽  
Author(s):  
S. R. D. Guy ◽  
W. D. E. Allan ◽  
Marc LaViolette ◽  
P. R. Underhill
Keyword(s):  
Gas Turbine ◽  
Ambient Air ◽  
Operating Conditions ◽  
Test Apparatus ◽  
Test Rig ◽  
Transport Aircraft ◽  
Test Conditions ◽  
Free Air ◽  
Primary Zone ◽  
Future Experimentation

Fuel atomizer condition can have a significant impact on gas turbine hot section component life. In order to investigate the depth of this influence, an experimental test apparatus was constructed, which allowed for optical access to the primary zone of a Rolls-Royce/Allison T56–A–15 turboprop combustion chamber. Test conditions were matched to simulate altitude cruise conditions of a C–130H Hercules military transport aircraft. T56 fuel nozzles of various conditions were tested in free air and then in the test rig using optical patternation techniques. Results indicated that spray characteristics observed in quiescent ambient air persisted under the representative engine operating conditions both burning and non-burning. The optical patternation tests also revealed the influence of combustion liner airflow patterns on the spray within the region of the primary zone that was observed. Conclusions were drawn such as the persistence of spray features observed in open air testing when nozzles were tested at engine representative conditions and recommendations were made for future experimentation.

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