Comparison of Cylinder Pressure Measurements on a Heavy-Duty Diesel Engine Using a Switching Adapter

2019 ◽  
Vol 141 (8) ◽  
Author(s):  
Adam B. Dempsey ◽  
Patrick J. Seiler ◽  
Simon Johnson
Keyword(s):  
High Pressure ◽  
Diesel Engine ◽  
Thermal Shock ◽  
Pressure Sensor ◽  
Absolute Pressure ◽  
Cylinder Pressure ◽  
Heavy Duty ◽  
Measurement Variability ◽  
Piezoresistive Sensor ◽  
The Impact

In this study, a variety of piezoelectric pressure transducer designs and mounting configurations were compared for measuring in-cylinder pressure on a heavy-duty single-cylinder diesel engine. A unique cylinder head design was used which allowed cylinder pressure to be measured simultaneously in two locations. In one location, various piezoelectric pressure transducers and mounting configurations were studied. In the other location, a Kistler water-cooled switching adapter with a piezoresistive pressure sensor was used. The switching adapter measured in-cylinder pressure during the low-pressure portion of the cycle. During the high-pressure portion of the cycle the sensor is protected from the high-pressure and high-temperature gases in the cylinder. Therefore, the piezoresistive sensor measured in-cylinder pressure highly accurately, without the impacts of short-term thermal drift, otherwise known as thermal shock. Additionally, the piezoresistive sensor is an absolute pressure sensor which does not require a baseline or “pegging” on every engine cycle. With this measurement setup, the amount of thermal shock and induced measurement variability was accurately assessed for the piezoelectric sensors. Data analysis techniques for quantifying the accuracy of a piezoelectric cylinder pressure measurement are also presented and discussed. It was observed that all the piezoelectric transducers investigated yielded very similar results regarding compression pressure, start of combustion, peak cylinder pressure, and the overall heat release rate shape. Differences emerged when studying the impact of the transducer mounting (e.g., recessed versus flush-mount). Recessed-mount transducers tended to yield a more accurate measurement of the cycle-to-cycle variability when compared to the baseline piezoresistive sensor. This is thought to be due to reduced levels of thermal shock, which can vary from cycle-to-cycle.

Comparison of Cylinder Pressure Measurements on a Heavy-Duty Diesel Engine Using a Switching Adapter

2018 ◽  
Author(s):  
Adam B. Dempsey ◽  
Patrick J. Seiler ◽  
Simon Johnson
Keyword(s):  
High Pressure ◽  
Diesel Engine ◽  
Thermal Shock ◽  
Pressure Sensor ◽  
Absolute Pressure ◽  
Pressure Measurements ◽  
Cylinder Pressure ◽  
Heavy Duty ◽  
Piezoresistive Sensor ◽  
The Impact

In this study, a variety of piezoelectric pressure transducer designs and mounting configurations were compared for measuring in-cylinder pressure on a heavy-duty single-cylinder diesel engine. A unique cylinder head design was used which allowed cylinder pressure to be measured simultaneously in two locations. In one location, various piezoelectric pressure transducers and mounting configurations were studied. In the other location, a Kistler water-cooled switching adapter with a piezoresistive pressure sensor was used. The switching adapter measured in-cylinder pressure during the low pressure portion of the cycle. During the high pressure portion of the cycle the sensor is protected from the high pressure and high temperature gases in the cylinder. Therefore, the piezoresistive sensor measured in-cylinder pressure highly accurately, without the impacts of short term thermal drift, otherwise known as thermal shock. Additionally, the piezoresistive sensor is an absolute pressure sensor which does not require a baseline or “pegging” on every engine cycle. With this measurement setup, the amount of thermal shock and induced measurement variability was accurately assessed for the piezoelectric sensors. Data analysis techniques for quantifying the accuracy of a piezoelectric cylinder pressure measurements are also presented and discussed. It was observed that all the piezoelectric transducers investigated yielded very similar results regarding compression pressure, start of combustion, peak cylinder pressure, and the overall heat release rate shape. Differences emerged when studying the impact of the transducer mounting (e.g., recessed vs. flush-mount). Recessed-mount transducers tended to yield a more accurate measurement of the cycle-to-cycle variability when compared to the baseline piezoresistive sensor. This is thought to be due to reduced levels of thermal shock, which can vary from cycle-to-cycle.

Numerical and Experimental Study on the Impact of Mild Cold EGR on Exhaust Emissions in a Biodiesel Fueled Diesel Engine

2021 ◽  
Author(s):  
Alex Oliveira ◽  
Junfeng Yang ◽  
Jose Sodre
Keyword(s):  
Diesel Engine ◽  
Fuel Consumption ◽  
Exhaust Emissions ◽  
Pollutant Emissions ◽  
Cylinder Pressure ◽  
Nox Formation ◽  
Ratio Distribution ◽  
Engine Model ◽  
Gas Recirculation ◽  
The Impact

Abstract This work evaluated the effect of cooled exhaust gas recirculation (EGR) on fuel consumption and pollutant emissions from a diesel engine fueled with B8 (a blend of biodiesel and Diesel 8:92%% by volume), experimentally and numerically. Experiments were carried out on a Diesel power generator with varying loads from 5 kW to 35 kW and 10% of cold EGR ratio. Exhaust emissions (e.g. THC, NOX, CO etc.) were measured and evaluated. The results showed mild EGR and low biodiesel content have minor impact of engine specific fuel consumption, fuel conversion efficiency and in-cylinder pressure. Meanwhile, the combination of EGR and biodiesel reduced THC and NOX up to 52% and 59%, which shows promising effect on overcoming the PM-NOX trade-off from diesel engine. A 3D CFD engine model incorporated with detailed biodiesel combustion kinetics and NOx formation kinetics was validated against measured in-cylinder pressure, temperature and engine-out NO emission from diesel engine. This valid model was then employed to investigate the in-cylinder temperature and equivalence ratio distribution that predominate NOx formation. The results showed that the reduction of NOx emission by EGR and biodiesel is obtained by a little reduction of the local in-cylinder temperature and, mainly, by creating comparatively rich combusting mixture.

First Unsteady Pressure Measurements With a Fast Response Cooled Total Pressure Probe in High Temperature Gas Turbine Environments

2010 ◽  
Author(s):  
Mehmet Mersinligil ◽  
Jean-Franc¸ois Brouckaert ◽  
Julien Desset
Keyword(s):  
High Pressure ◽  
Pressure Sensor ◽  
Total Pressure ◽  
Fast Response ◽  
Design Stage ◽  
Absolute Pressure ◽  
Pressure Probe ◽  
Probe Design ◽  
Flame Tube ◽  
Blade Passing Frequency

This paper presents the first experimental engine and test rig results obtained from a fast response cooled total pressure probe. The first objective of the probe design was to favor continuous immersion of the probe into the engine to obtain time series of pressure with a high bandwidth and therefore statistically representative average fluctuations at the blade passing frequency. The probe is water cooled by a high pressure cooling system and uses a conventional piezo-resistive pressure sensor which yields therefore both time-averaged and time-resolved pressures. The initial design target was to gain the capability of performing measurements at the temperature conditions typically found at high pressure turbine exit (1100–1400K) with a bandwidth of at least 40kHz and in the long term at combustor exit (2000K or higher). The probe was first traversed at the turbine exit of a Rolls-Royce Viper turbojet engine, at exhaust temperatures around 750 °C and absolute pressure of 2.1bars. The probe was able to resolve the high blade passing frequency (≈23kHz) and several harmonics up to 100kHz. Besides the average total pressure distributions from the radial traverses, phase-locked averages and random unsteadiness are presented. The probe was also used in a virtual three-hole mode yielding unsteady yaw angle, static pressure and Mach number. The same probe was used for measurements in a Rolls-Royce intermediate pressure burner rig. Traverses were performed inside the flame tube of a kerosene burner at temperatures above 1600 °C. The probe successfully measured the total pressure distribution in the flame tube and typical frequencies of combustion instabilities were identified during rumble conditions. The cooling performance of the probe is compared to estimations at the design stage and found to be in good agreement. The frequency response of the probe is compared to cold shock tube results and a significant increase in the natural frequency of the line-cavity system formed by the conduction cooled screen in front of the miniature pressure sensor were observed.

Impact of military JP-8 fuel on heavy-duty diesel engine performance and emissions

2007 ◽  
Vol 221 (8) ◽  
pp. 957-970 ◽  
Author(s):  
G Fernandes ◽  
J Fuschetto ◽  
Z Filipi ◽  
D Assanis ◽  
H McKee
Keyword(s):  
Particulate Matter ◽  
Diesel Engine ◽  
Fuel Economy ◽  
Engine Performance ◽  
Heavy Duty ◽  
Heavy Duty Diesel Engine ◽  
Performance And Emissions ◽  
Heavy Duty Diesel ◽  
Engine Performance And Emissions ◽  
The Impact

Investigating the impact of jet fuel on diesel engine performance and emissions is very important for military vehicles, due to the US Army Single Fuel Forward Policy mandating that deployed vehicles must refuel with aviation fuel JP-8. There is a known torque and fuel economy penalty associated with the operation of a diesel engine with JP-8 fuel, due to its lower density and viscosity. On the other hand, a few experimental studies have suggested that kerosene-based fuels have the potential for lowering exhaust emissions, especially particulate matter, compared to diesel fuel #2 (DF-2). However, studies so far have typically focused on quantifying the effects of simply replacing the regular DF-2 with JP-8, rather than fully investigating the reasons behind the observed differences. This research evaluates the effect of using JP-8 fuel in a heavy-duty diesel engine on fuel injection, combustion, performance, and emissions, and subsequently utilizes the obtained insight to propose changes to the engine calibration to mitigate the impact of the trade-offs. Experiments were carried out on a Detroit Diesel Corporation (DDC) S60 engine outfitted with exhaust gas recirculation (EGR). The results indicate that torque and fuel economy of diesel fuel can be matched, without smoke or NO x penalty, by increasing the duration of injection to compensate for the lower fuel density. The lower cetane number of JP-8 caused an increased ignition delay and increased premixed combustion, and their cumulative effect led to relatively unchanged combustion phasing. Under almost all conditions, JP-8 led to lower NO x and particulate matter (PM) emissions and shifted the NO x-PM trade-off favourably.

The Effects of Intake Plenum Volume on the Performance of a Small Naturally Aspirated Restricted Engine

2009 ◽  
Author(s):  
Leonard J. Hamilton ◽  
Jim S. Cowart ◽  
Jasen E. Lee ◽  
Ryan E. Amorosso
Keyword(s):  
Steady State ◽  
Performance Metrics ◽  
Full Range ◽  
Engine Performance ◽  
Absolute Pressure ◽  
Cylinder Pressure ◽  
Formula Sae ◽  
Indicated Mean Effective Pressure ◽  
Competition Rules ◽  
The Impact

Intake tuning is a widely recognized method for optimizing the performance of a naturally aspirated engine for motorsports applications. Wave resonance and Helmholtz theories are useful for predicting the impact of intake runner length on engine performance. However, there is very little information in the literature regarding the effects of intake plenum volume. The goal of this study was to determine the effects of intake plenum volume on steady state and transient engine performance for a restricted naturally aspirated engine for Formula SAE (FSAE) vehicle use. Testing was conducted on a four cylinder 600 cc motorcycle engine fitted with a 20 mm restrictor in compliance with FSAE competition rules. Plenum sizes were varied from 2 to 10 times engine displacement (1.2 to 6.0 L) and engine speeds were varied from 3,000 to 12,500 RPM. Performance metrics including volumetric efficiency, torque and power were recorded at steady state conditions. Experimental results showed that engine performance increased modestly as plenum volume was increased from 2 to 8 times engine displacement (4.8L). Increasing plenum volume beyond 4.8L resulted in significant improvement in performance parameters. Overall, peak power was shown to increase from 54 kW to 63 kW over the range of plenums tested. Additionally, transient engine performance was evaluated using extremely fast (60 msec) throttle opening times for the full range of plenum sizes tested. In-cylinder pressure was used to calculate cycle-resolved gross indicated mean effective pressure (IMEPg) development during these transients. Interestingly, the cases with the largest plenum sizes only took 1 – 2 extra cycles (30–60 msec) to achieve maximum IMEPg levels when compared to the smaller volumes. In fact the differences were so minor that it would be doubtful that a driver would notice the lag. Additional metrics included time for the plenums to fill and an analysis of manifold absolute pressure (MAP) and peak in-cylinder pressure development during and after the throttle transient. Plenums below 4.8L completely filled even before the transient was completed.

The Impact Upon Durability of Heavy-Duty Diesel Engine Using 5 Percentage Biodiesel

2013 ◽  
Vol 6 (1) ◽  
pp. 241-250 ◽  
Author(s):  
Yong-Yuan Ku ◽  
Ko Wei Lin ◽  
Ya-Lun Chen ◽  
Ching-Fu Liao
Keyword(s):  
Diesel Engine ◽  
Heavy Duty ◽  
Heavy Duty Diesel Engine ◽  
Heavy Duty Diesel ◽  
The Impact

scholarly journals Tailored Air-Handling System Development for Gasoline Compression Ignition in a Heavy-Duty Diesel Engine

2021 ◽  
Vol 7 ◽  
Author(s):  
Praveen Kumar ◽  
Yu Zhang ◽  
Michael Traver ◽  
John Watson
Keyword(s):  
High Pressure ◽  
Steady State ◽  
Diesel Engine ◽  
Low Pressure ◽  
Single Stage ◽  
Variable Geometry ◽  
Compression Ignition ◽  
Heavy Duty ◽  
Variable Geometry Turbocharger ◽  
Handling System

The simultaneous application of new low-NOx emissions standards and greenhouse gas (GHG) rules has placed great pressure on the commercial vehicle industry and has driven demand for innovative solutions. One potential solution, gasoline compression ignition (GCI), utilizes gasoline’s lower reactivity to promote partially premixed combustion and extract efficiency while reducing the PM-NOx trade-off curve. Gasoline’s volatility allows for the use of higher levels of exhaust gas recirculation (EGR), a key enabler of GCI combustion. In order to deliver higher levels of EGR while maintaining sufficient boost pressure, a tailored and efficient air-handling system is critical. This work presents the analysis-led development of a low-NOx GCI air-handling system including both turbocharger matching and EGR configuration for a prototype heavy-duty GCI engine based on a model year 2013 Cummins ISX diesel engine using low octane gasoline (RON80). In the analysis-driven development process, a 1D engine system-level analysis was closely coupled with closed-cycle 3D CFD GCI combustion development. Three different boost systems were investigated using a validated 1D engine model: 1) the production turbocharger; 2) an off-the-shelf single-stage waste-gate turbocharger; 3) a prototype single-stage variable geometry turbocharger. For each boost system, three EGR configurations were evaluated: 1) a high-pressure EGR route; 2) a low-pressure EGR route; 3) a dual-loop EGR route. The air-handling system performance was first investigated over five steady-state engine operating conditions extracted from the ramped modal cycle supplemental emissions test. Then, through cosimulation using a Simulink-based engine controls model, the best performing candidates under transient operation through the Heavy-Duty Federal Test Procedure certification cycle were identified. The production turbocharger, designed for 4–6 g/kWh engine-out NOx, suffered from low combined turbocharger efficiency under the low-NOx GCI thermal boundary conditions. The prototype 1-Stage variable geometry turbocharger, when used with a high-pressure EGR configuration, demonstrated higher combined efficiencies, while the waste-gate turbocharger showed the best results when used with a dual-loop EGR system. All low-pressure only EGR configurations were found to incur additional pumping penalties due to the need for a back pressure valve to drive sufficient EGR levels. In the transient test cycle analysis, the single-stage high-pressure EGR system was capable of delivering the target boost and EGR, while the off-the-shelf waste-gate turbocharger, with its higher mass inertia, showed slower turbine response and a resulting lag in boost response. Unsurprisingly, the dual-loop EGR system also suffered from delays in EGR delivery during engine acceleration. In summary, the prototype single-stage variable geometry turbocharger with a high-pressure EGR system produced the best performance over both the steady-state and transient engine cycles and was identified as the best candidate for the prototype low-NOx heavy-duty GCI engine.

Aerodynamic Optimization of High Pressure Turbine and Interstage Duct in a Two-Stage Air System for a Heavy-Duty Diesel Engine

2017 ◽  
Author(s):  
Uswah Khairuddin ◽  
Aaron W. Costall
Keyword(s):  
High Pressure ◽  
Diesel Engine ◽  
Operating Point ◽  
Heavy Duty ◽  
Aerodynamic Optimization ◽  
High Pressure Turbine ◽  
Two Stage ◽  
Turbine Wheel ◽  
Heavy Duty Diesel Engine ◽  
Heavy Duty Diesel

Turbochargers are a key technology for reducing the fuel consumption and CO2 emissions of heavy-duty internal combustion engines by enabling greater power density, which is essential for engine downsizing and downspeeding. This in turn raises turbine expansion ratio levels and drives the shift to air systems with multiple stages, which also implies the need for interconnecting ducting, all of which is subject to tight packaging constraints. This paper considers the challenges in the aerodynamic optimization of the exhaust side of a two-stage air system for a Caterpillar 4.4-litre heavy-duty diesel engine, focusing on the high pressure turbine wheel and interstage duct. Using the current production designs as a baseline, a genetic algorithm-based aerodynamic optimization process was carried out separately for the wheel and duct components in order to minimize the computational effort required to evaluate seven key operating points. While efficiency was a clear choice for the cost function for turbine wheel optimization, the most appropriate objective for interstage duct optimization was less certain, and so this paper also explores the resulting effect of optimizing the duct design for different objectives. Results of the optimization generated differing turbine wheel and interstage duct designs depending on the corresponding operating point, thus it was important to check the performance of these components at every other operating point, in order to determine the most appropriate designs to carry forward. Once the best compromise high pressure turbine wheel and interstage duct designs were chosen, prototypes of both were manufactured and then tested together against the baseline designs to validate the CFD predictions. The best performing high pressure turbine design, wheel A, was predicted to show an efficiency improvement of 2.15 percentage points, for on-design operation. Meanwhile, the optimized interstage duct contributed a 0.2 and 0.5 percentage-point efficiency increase for the high and low pressure turbines, respectively.

Diesel Engine Research at High B.M.E.P.

1985 ◽  
Vol 199 (4) ◽  
pp. 285-292 ◽  
Author(s):  
A G Osborne
Keyword(s):  
High Pressure ◽  
Diesel Engine ◽  
Compression Ratio ◽  
Engine Performance ◽  
Research Programme ◽  
Boost Pressure ◽  
Effective Pressure ◽  
Cylinder Pressure ◽  
Experimental Part ◽  
Peak Cylinder Pressure

Demands for more power from the turbocharged diesel, without increase in bulk or weight, has led to an increase in levels of mean effective pressure by the application of high-pressure turbocharging. An investigation was conducted to determine engine performance under high b.m.e.p. conditions and this paper presents results of the experimental part of the research programme. Test work was carried out on a single-cylinder research engine equipped with an independent pressure-charging facility. Boost pressure ratios up to 6.2:1 were used with the geometric compression ratio reduced, in stages, to 8:1, to limit peak cylinder pressure. Power levels up to 35.4 bar b.m.e.p. were produced.

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