An Investigation Into the Causes of Transient Particulate Matter Spikes in Production Diesel Engines

2011 ◽  
Author(s):  
Indranil Brahma
Keyword(s):  
Particulate Matter ◽  
Diesel Engines ◽  
Fuel Efficiency ◽  
Volumetric Efficiency ◽  
Pressure Differential ◽  
Intake Manifold ◽  
Engine Operation ◽  
Transient Data ◽  
Charge Flow ◽  
Oxygen Ratio

Particulate matter spikes occurring during transient engine operation have important health implications. This paper investigates the root cause of particulate matter spikes in modern electronically controlled diesel engines that impose strict fuel-Oxygen ratio limits during the turbocharger lag period. It is proposed that these spikes can be significantly reduced by improved estimation of transient charge flow through the engine. Through transient data analysis and with the aid of transient data based empirical models, it has been shown that the fuel-Oxygen ratio restrictions imposed by contemporary engine controllers are ineffective during transients because of temporary but large differences between exhaust and intake manifold pressures during aggressive transients resulting in inaccurate volumetric efficiency and charge flow estimation. Steady state experiments with artificially generated high engine manifold pressure differentials have been conducted to support this hypothesis. The engine manifold pressure differential hypothesis is a consequence of previous investigations to explain the baffling inability of empirical data based models to predict the magnitudes of transient particulate matter spikes. Accurate volumetric efficiency estimation during transients can make the fuel-Oxygen ratio limits more effective at reducing opacity spikes. It would also make model based transient calibration more useful by increasing the accuracy of particulate matter models and by directing any dynamic optimization process to mould calibratable surfaces to minimize engine manifold pressure differential spikes. Fuel efficiency benefits due to lower pumping losses during transients and lower regeneration penalties would also result.

Soot Load Sensing in a Diesel Particulate Filter via Electrical Capacitance Tomography

2013 ◽  
Author(s):  
Ragibul Huq ◽  
Sohel Anwar
Keyword(s):  
Particulate Matter ◽  
Diesel Engines ◽  
Diesel Particulate Filter ◽  
Internal Combustion Engines ◽  
Fuel Efficiency ◽  
Particulate Filter ◽  
Electrical Capacitance Tomography ◽  
Electrical Capacitance ◽  
Diesel Particulate ◽  
Capacitance Tomography

Diesel engines are widely used in heavy duty trucks and off road vehicles due to their fuel efficiency and high power outputs. Environmental regulatory agencies have pushed ever stringent regulations on all internal combustion engines, including Diesel engines on gaseous as well as particulates (soot) emissions. In order to meet today’s and tomorrow’s stringent emission requirements, modern diesel engines are equipped with diesel particulate filters (DPF’s), as well as on-board technologies to evaluate the status of DPF. In course of time, particulate matter (soot) will be deposited inside the DPFs which tend to clog the filter and hence generate a back pressure in the exhaust system, negatively impacting the fuel efficiency. To remove the soot build-up, regeneration (active or passive) of the DPF must be done as an engine exhaust after treatment process at pre-determined time intervals. Since the regeneration process consume fuel, a robust and efficient operation based on accurate knowledge of the particulate matter deposit (or soot load) becomes essential in order to keep the fuel consumption at a minimum. In this paper, we propose a sensing method for a DPF that can accurately measure in-situ soot load using Electrical Capacitance Tomography (ECT). Simulation results show that the proposed method offers an effective way to accurately estimate the soot load in DPF. The proposed method is expected to have a profound impact in improving overall PM filtering efficiency (and thereby fuel efficiency), and durability of a Diesel Particulate Filter (DPF) through appropriate closed loop regeneration operation.

Dynamic cylinder activation in diesel engines

2018 ◽  
Vol 20 (8-9) ◽  
pp. 849-861 ◽  
Author(s):  
Dheeraj B Gosala ◽  
Cody M Allen ◽  
Gregory M Shaver ◽  
Lisa Farrell ◽  
Edward Koeberlein ◽  
...  
Keyword(s):  
Thermal Management ◽  
Diesel Engines ◽  
Fuel Efficiency ◽  
Engine Operation ◽  
Cylinder Deactivation ◽  
Fuel Savings ◽  
Cycle Basis ◽  
Strong Candidate ◽  
Number Of Cycles ◽  
Fixed Cylinder

Cylinder deactivation has been recently demonstrated to have fuel savings and aftertreatment thermal management benefits at low to moderate loads compared to conventional operation in diesel engines. This study discusses dynamic cylinder activation as an effective variant to fixed diesel engine cylinder deactivation. The set of inactive and active cylinders varies on a cycle-by-cycle basis during dynamic cylinder activation. This enables greater control over forcing frequencies of the engine, thereby allowing the engine to operate away from the drivetrain resonant frequency at all engine speeds, while maintaining similar fuel savings, thermal management, and emission characteristics as fixed cylinder deactivation. Additional benefits of dynamic cylinder activation include a reduction in the consecutive number of cycles a given cylinder is deactivated, and more even cylinder usage. Enablement of engine operation without exciting drivetrain resonant frequencies at similar fuel efficiency and emissions as fixed cylinder deactivation makes dynamic cylinder activation a strong candidate to augment the benefits already demonstrated for fixed cylinder deactivation.

On the Use of VVT Strategy for the Maximum Volumetric Efficiency in Turbocharged Diesel Engines

2006 ◽  
Author(s):  
S. Ahmad Ghazi Mir Saied ◽  
Amir H. Shamdani ◽  
Amir H. Shamekhi
Keyword(s):  
Diesel Engine ◽  
Diesel Engines ◽  
Mass Conservation ◽  
Management Control ◽  
Volumetric Efficiency ◽  
Valve Train ◽  
Intake Manifold ◽  
Power Performance ◽  
Optimal Control Strategy ◽  
Variable Valve

This paper presents a variable valve lifting methodology for turbocharged diesel engines. For this purpose, the diesel engine is modeled based on a modified mean-value engine modeling. An optimal control strategy is used for maximum volumetric efficiency acquirement. Using camless valve train strategy makes better fuel economy and improved air intake characteristics throughout the engine operating map. The system is capable of continuously, independently and virtually controlling all standard parameters of variable valve motion. This permits optimization of valve events for any operating condition without compromise. The optimized intake valve profile is determined, to have the best volumetric efficiency and proper operation for each running condition based on the existing model make use of numerical techniques. The model used in this paper is validated using simulation results of references. The model treats the cylinder and the manifolds as thermodynamic control volumes by using the filling and emptying method, solving energy and mass conservation equations with sub models for intake manifold, variable valve timing, cylinder breathing dynamics and turbocharger including turbine and compressor. This model is a crank angle based dynamic nonlinear model of a four-cylinder turbocharged (TC) diesel engine, which captures the interactions among the VVT actuation, the turbocharger dynamics and the cylinder-to-cylinder breathing characteristics. The model have been implemented in Matlab/Simulink and tested. This work shows the results obtained for air management control in a turbocharged diesel engine, specifically, manifold pressure and air mass flow. These variables are often required to achieve better power performance and lower emissions.

Development of a Soot Load Sensor Using Electrical Capacitance Imaging

2015 ◽  
Vol 137 (11) ◽  
Author(s):  
Ragibul Huq ◽  
Sohel Anwar
Keyword(s):  
Particulate Matter ◽  
Diesel Engines ◽  
Fuel Efficiency ◽  
Exhaust System ◽  
Particulate Filter ◽  
Electrical Capacitance ◽  
Engine Exhaust ◽  
Efficient Operation ◽  
The Status ◽  
Exhaust After Treatment

This paper presents an innovative approach for measuring particulate matter deposition (soot load) in a diesel particulate filter (DPF) using electrical capacitance imaging. Emission regulations on diesel engines for gaseous as well as particulate matter (soot) emissions are getting stringent every few years by the environment regulatory agencies. Modern diesel engines are equipped with DPFs, as well as on-board technologies to evaluate the status of DPF, because complete knowledge of DPF soot load is very critical for robust and efficient operation of the engine exhaust after treatment system. In course of time, soot will be deposited inside the DPF which will clog the filter and generate a back pressure in the exhaust system, negatively impacting the fuel efficiency. To remove the soot build-up, regeneration (active or passive) of the DPF must be done as an engine exhaust after treatment process periodically. Since the regeneration process consumes fuel, a robust and efficient operation based on accurate knowledge of the soot load becomes essential in order to keep the fuel consumption at a minimum. In this paper, we propose a novel sensing method for a DPF that can measure in situ soot load using electrical capacitance imaging. Experimental results show that the proposed method offers an effective way to measure the soot load in DPF. The proposed method is expected to have a profound impact in improving overall DPF filtering efficiency and durability of a DPF through appropriate closed-loop regeneration operation.

Assessment of Solar Steam Injection in Gas Turbines

2016 ◽  
Author(s):  
C. Kalathakis ◽  
N. Aretakis ◽  
I. Roumeliotis ◽  
A. Alexiou ◽  
K. Mathioudakis
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Fuel Efficiency ◽  
Thermal Power ◽  
Steam Injection ◽  
Power Production ◽  
Engine Operation ◽  
Efficiency Increase ◽  
Solar Receiver ◽  
Steam Production

The concept of solar steam production for injection in a gas turbine combustion chamber is studied for both nominal and part load engine operation. First, a 5MW single shaft engine is considered which is then retrofitted for solar steam injection using either a tower receiver or a parabolic troughs scheme. Next, solar thermal power is used to augment steam production of an already steam injected single shaft engine without any modification of the existing HRSG by placing the solar receiver/evaporator in parallel with the conventional one. For the case examined in this paper, solar steam injection results to an increase of annual power production (∼15%) and annual fuel efficiency (∼6%) compared to the fuel-only engine. It is also shown that the tower receiver scheme has a more stable behavior throughout the year compared to the troughs scheme that has better performance at summer than at winter. In the case of doubling the steam-to-air ratio of an already steam injected gas turbine through the use of a solar evaporator, annual power production and fuel efficiency increase by 5% and 2% respectively.

Fuel Efficiency – Challenges and Innovations in Emulsified Fuel Technology

2015 ◽  
Author(s):  
Jerry Ng ◽  
Kaisa Honkanen
Keyword(s):  
Diesel Engines ◽  
Fuel Injection ◽  
Fuel Efficiency ◽  
Combustion Efficiency ◽  
Secondary Atomization ◽  
Emulsified Fuel ◽  
Main Challenge ◽  
Marine Diesel ◽  
Initial Fuel ◽  
Fuel Technology

Emulsified fuel technology has been developed since the early 1980’s to the improve combustion efficiency of marine diesel engines by creating a secondary atomization effect after the initial fuel injection. The main challenge is to measure the improved sfoc of ships accurately and reliably. This paper presents a proposed method to measure the sfoc accurately and reliably to the order of 1%. Electronic governor also poses new challenge to measuring the sfoc of ships burning emulsified fuel. Meanwhile, fuel types supplied to ship owners are of increased varying properties although still complying to ISO8217 standard. This paper describes the innovations in emulsified fuel technology that were developed to meet these challenges.

Fuel Quality Effects on Particulate Matter Emissions from Light- and Heavy-Duty Diesel Engines

1994 ◽  
Author(s):  
C. J. J. Den Ouden ◽  
R. H. Clark ◽  
L. T. Cowley ◽  
R. J. Stradling ◽  
W. W. Lange ◽  
...  
Keyword(s):  
Particulate Matter ◽  
Diesel Engines ◽  
Fuel Quality ◽  
Heavy Duty ◽  
Particulate Matter Emissions ◽  
Heavy Duty Diesel

scholarly journals Performance evaluation of common rail direct injection (CRDI) engine fuelled with Uppage Oil Methyl Ester (UOME)

2015 ◽  
Vol 4 (1) ◽  
pp. 1-10 ◽  
Author(s):  
D.N. Basavarajappa ◽  
N. R. Banapurmath ◽  
S.V. Khandal ◽  
G. Manavendra
Keyword(s):  
Diesel Engine ◽  
Methyl Ester ◽  
Diesel Engines ◽  
High Speed ◽  
Alternative Fuels ◽  
High Pressures ◽  
Fuel Injection ◽  
Injection Timing ◽  
Engine Operation ◽  
Performance And Emission

For economic and social development of any country energy is one of the most essential requirements. Continuously increasing price of crude petroleum fuels in the present days coupled with alarming emissions and stringent emission regulations has led to growing attention towards use of alternative fuels like vegetable oils, alcoholic and gaseous fuels for diesel engine applications. Use of such fuels can ease the burden on the economy by curtailing the fuel imports. Diesel engines are highly efficient and the main problems associated with them is their high smoke and NOx emissions.  Hence there is an urgent need to promote the use of alternative fuels in place of high speed diesel (HSD) as substitute. India has a large agriculture base that can be used as a feed stock to obtain newer fuel which is renewable and sustainable. Accordingly Uppage oil methyl ester (UOME) biodiesel was selected as an alternative fuel. Use of biodiesels in diesel engines fitted with mechanical fuel injection systems has limitation on the injector opening pressure (300 bar). CRDI system can overcome this drawback by injecting fuel at very high pressures (1500-2500 bar) and is most suitable for biodiesel fuels which are high viscous. This paper presents the performance and emission characteristics of a CRDI diesel engine fuelled with UOME biodiesel at different injection timings and injection pressures. From the experimental evidence it was revealed that UOME biodiesel yielded overall better performance with reduced emissions at retarded injection timing of -10° BTDC in CRDI mode of engine operation.

scholarly journals The analysis of the influence of stabilization conditions of working filters on the sample mass of diesel particulates

2012 ◽  
Vol 148 (1) ◽  
pp. 48-52
Author(s):  
Andrey POLIVYANCHUK ◽  
Oleg IGNATOV
Keyword(s):  
Particulate Matter ◽  
Measurement Error ◽  
Measurement Uncertainty ◽  
Diesel Engines ◽  
Final Part ◽  
Heavy Duty ◽  
Gravimetric Measurement ◽  
Sample Mass ◽  
Particulate Matter Emission ◽  
Passenger Vehicles

The paper presents the influence of the conditioning of filters used in the gravimetric measurement of particulate matter emission on the mass of the particles. The influence of the time of filter conditioning on the obtained results as well as the influence of the temperature of the sample before the filtering on the measurement uncertainty have been subjected to analysis. In the further part the influence of the ranges of temperatures of the filter conditioning on the mass of the PM sample have been determined as per the standardization for the tests of diesel engines fitted in passenger vehicles, heavy-duty vehicles and buses (regulation R-83 and R-49 respectively). In the final part recommendations have been formulated that allow a reduction of the measurement error.

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