The effect of heat transfer on performance of the Diesel cycle and exergy of the exhaust gas stream in a LHR Diesel engine at the optimum injection timing

2005 ◽  
Vol 46 (2) ◽  
pp. 167-179 ◽  
Author(s):  
Adnan Parlak
Keyword(s):  
Heat Transfer ◽  
Diesel Engine ◽  
Injection Timing ◽  
Exhaust Gas ◽  
Diesel Cycle

Control-Oriented Physics-Based NOX Emission Model for a Diesel Engine With Exhaust Gas Recirculation

2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Saravanan Duraiarasan ◽  
Rasoul Salehi ◽  
Anna Stefanopoulou ◽  
Siddharth Mahesh ◽  
Marc Allain
Keyword(s):  
Diesel Engine ◽  
Test Procedure ◽  
Flame Temperature ◽  
Exhaust Gas Recirculation ◽  
Nox Emission ◽  
Injection Timing ◽  
Exhaust Gas ◽  
Engine Control ◽  
Gas Recirculation ◽  
The Impact

Abstract Stringent NOX emission norm for heavy duty vehicles motivates the use of predictive models to reduce emissions of diesel engines by coordinating engine parameters and aftertreatment. In this paper, a physics-based control-oriented NOX model is presented to estimate the feedgas NOX for a diesel engine. This cycle-averaged NOX model is able to capture the impact of all major diesel engine control variables including the fuel injection timing, injection pressure, and injection rate, as well as the effect of cylinder charge dilution and intake pressure on the emissions. The impact of the cylinder charge dilution controlled by the engine exhaust gas recirculation (EGR) in the highly diluted diesel engine of this work is modeled using an adiabatic flame temperature predictor. The model structure is developed such that it can be embedded in an engine control unit without any need for an in-cylinder pressure sensor. In addition, details of this physics-based NOX model are presented along with a step-by-step model parameter identification procedure and experimental validation at both steady-state and transient conditions. Over a complete federal test procedure (FTP) cycle, on a cumulative basis the model prediction was more than 93% accurate.

Effect of hydraulic flow rate, injection timing, and exhaust gas recirculation on particulate and gaseous emissions in a light-duty diesel engine

2019 ◽  
Vol 234 (5) ◽  
pp. 1279-1293 ◽  
Author(s):  
Khawar Mohiuddin ◽  
Minhoo Choi ◽  
Junkyu Park ◽  
Sungwook Park
Keyword(s):  
Diesel Engine ◽  
Flow Rate ◽  
Particle Number ◽  
Exhaust Gas Recirculation ◽  
Injection Timing ◽  
Exhaust Gas ◽  
Gaseous Emissions ◽  
Spray Tip Penetration ◽  
Hydraulic Flow ◽  
Gas Recirculation

Nozzle hydraulic flow rate is a critical parameter that affects the combustion process and plays a vital role in the production of emissions from a diesel engine. In this study, injection characteristics, such as normalized injection rate and spray tip penetration, were analyzed for different hydraulic flow rate injectors with the help of spray experiments. To further investigate the effects of hydraulic flow rate on engine-out particulate and gaseous emissions, engine experiments were performed for different values of hydraulic flow rate in multiple injectors. Various operating conditions and loading configurations were examined, and the effects of varying start of injection and exhaust gas recirculation rates for different hydraulic flow rates were analyzed. A separate Pegasor Particle Sensor (PPS-M) sensor was used to measure and collect data on the particle number, and an analysis was conducted to investigate the relation of particle number with hydraulic flow rate, injection timing, and exhaust gas recirculation rate. Results of the spray experiment exhibited a decreasing injection duration and increasing spray tip penetration with increasing hydraulic flow rate. Effect of hydraulic flow rate on combustion and emission characteristics were analyzed from engine experiment results. Least ignition delay was achieved using a smaller hole diameter, retarded injection timing, and lowest EGR%. Higher hydraulic flow rate with retarded injection timing and higher EGR% helped in reduction of NOx emissions and brake-specific fuel consumption, but particulate emissions were increased. Best particulate matter–NOx trade-off was achieved with lowest hydraulic flow rate.

scholarly journals Calculation studies of the influence of exhaust gas recirculation on the characteristics of the natural gas-fueled diesel engine

2021 ◽  
Vol 2061 (1) ◽  
pp. 012065
Author(s):  
I I Libkind ◽  
A V Gonturev
Keyword(s):  
Diesel Engine ◽  
Natural Gas ◽  
Fuel Mixture ◽  
Exhaust Gas Recirculation ◽  
Intake Manifold ◽  
Nox Emissions ◽  
Exhaust Gas ◽  
Diesel Cycle ◽  
Gas Fueled ◽  
Gas Recirculation

Abstract When converting diesel engines to run on natural gas on the gas-diesel cycle, additional problems arise associated with the high thermal stress of the exhaust valves and valve seats at high loads and engine speeds. There is also an increase in NOx emissions due to higher combustion temperatures of natural gas. One of the ways to improve the economic and environmental performance of engines operating on a gas-diesel cycle with a lean air-fuel mixture is to optimize the combustion of the air-fuel mixture by using an exhaust gas recirculation system (EGR). The principle of operation of this system is as follows: exhaust gas entering the intake manifold and further into the combustion chamber reduces the oxygen concentration in the air-fuel mixture, which leads to a dilution effect and, accordingly, to a decrease in combustion temperature and a decrease in NOx content. In order to study the influence of EGR on the dual-fuel gas and diesel engine parameters in the AVL Boost software package, a computer model of the existing 6ChN13/15 engine was developed. A low-pressure EGR system with an exhaust gas cooler was simulated on this engine. Values of NOx emissions, brake specific fuel consumption (BSFC) and brake efficiency have been obtained at different recirculation rate by calculation method. These values allow to estimate the feasibility of using a cooled EGR in a natural gas-fueled diesel engine.

Investigation of Emission Characteristic of a Diesel Engine by Simulation

2011 ◽  
Vol 80-81 ◽  
pp. 752-756
Author(s):  
You Hong Xiao ◽  
Pei Lin Zhou
Keyword(s):  
Diesel Engine ◽  
Air Temperature ◽  
Emission Characteristic ◽  
Injection Timing ◽  
Emission Characteristics ◽  
Exhaust Gas ◽  
No Emission ◽  
Variable Parameters ◽  
Hc Emissions ◽  
Gas Recirculation

This paper presented results of a study on emission characteristics of diesel engines. A numerical simulation model for a diesel engine was established by GT-POWER. Emission species studied include of NO, CO and HC. The developed model was validated by engine tests under laboratory condition. Based on the model, the simulation changing the variable parameters including injection timing, intake air temperature and EGR (exhaust gas recirculation) ratio were carried out to study their effect on emissions. The simulation results showed that with the decrease of CA BTDC, intake air temperature, compression ratio and EGR ratio respectively, the NO emission decreased. However, the CO and HC emissions increased.

Effect of exhaust gas recirculation and charge inlet temperature on performance, combustion, and emission characteristics of diesel engine with bael oil blends

2018 ◽  
Vol 29 (3) ◽  
pp. 372-391 ◽  
Author(s):  
M Krishnamoorthi ◽  
R Malayalamurthi
Keyword(s):  
Diesel Engine ◽  
Compression Ratio ◽  
Exhaust Gas Recirculation ◽  
Inlet Temperature ◽  
Injection Timing ◽  
Emission Characteristics ◽  
Exhaust Gas ◽  
Engine Operation ◽  
Engine Load ◽  
Gas Recirculation

The threat of fossil fuel depletion and augmented environmental pollution caused by diesel fleets can be curbed by adopting suitable fuel and engine modifications. In the present work, effects of engine speed (r/min), injection timing, injection pressure and compression ratio on performance and emission characteristics of a compression ignition engine were investigated. The ternary test fuel of 65% diesel + 25% bael oil + 10% diethyl ether has been used, where the tests have been conducted at different charge inlet temperature and exhaust gas recirculation. All the experiments were conducted at the trade-off engine load that is 75% engine load. When the diesel engine operating with 320 K charge inlet temperature, brake thermal efficiency has been improved to 28.6%. Meanwhile reduced emission levels of carbon monoxide (0.025%) and hydrocarbon (12.3 ppm) were observed during the engine operation with 320 K charge inlet temperature and compression ratio of 18:1. The oxides of nitrogen have been reduced to 226 ppm at 16:1 compression ratio with 30% exhaust gas recirculation mode.

Performance of a Low Heat Rejection Diesel Engine With Air Gap Insulated Piston

1999 ◽  
Vol 121 (3) ◽  
pp. 530-539 ◽  
Author(s):  
K. Rama Mohan ◽  
C. M. Vara Parasad ◽  
M. V. S. Murali Krishna
Keyword(s):  
Finite Element ◽  
Diesel Engine ◽  
Finite Element Modeling ◽  
Air Gap ◽  
Combustion Model ◽  
Injection Timing ◽  
Exhaust Gas ◽  
Full Load ◽  
Piston Crown ◽  
Finite Element Prediction

A threaded air gap insulated piston provided effective insulation without causing sealing problems. The performance of the diesel engine with the air gap insulated piston was obtained with different piston crown materials, at differing magnitudes of air gap with varying injection timings. The engine using Nimonic for the piston crown with an air gap of 3 mm at an injection timing of 29.5° bTDC reduced the BSFC by 12 percent at part loads and 4 percent at full load. The performance in terms of P-θ and T-θ was predicted employing a zero dimensional multizone combustion model, and the model results have been validated with measured pressures and the exhaust gas temperatures. More appropriate piston surface temperatures were employed in Annand’s equation to improve the computer predictions using finite element modeling of the piston. The measured temperatures of air in the air gap using an L-link mechanism provided excellent validation for the finite element prediction of isotherms in the piston.

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