Light-Duty Diesel Emission Correction Factors for Ambient Conditions

1977 ◽  
Author(s):  
Charles T. Hare ◽  
Ronald L. Bradow
1978 ◽  
Vol 100 (4) ◽  
pp. 640-646 ◽  
Author(s):  
P. Donovan ◽  
T. Cackette

A set of factors which reduces the variability due to ambient conditions of the hydrocarbon, carbon monoxide, and oxides of nitrogen emission indices has been developed. These factors can be used to correct an emission index to reference day ambient conditions. The correction factors, which vary with engine rated pressure ratio for NOx and idle pressure ratio for HC and CO, can be applied to a wide range of current technology gas turbine engines. The factors are a function of only the combustor inlet temperature and ambient humidity.


2015 ◽  
Author(s):  
Joe Noto ◽  
Athul Radhakrishnan ◽  
Ye Sun ◽  
Josh Ferreira ◽  
Marc Compere

The combination of increasingly challenging emissions regulations and impending Corporate Average Fuel Economy (CAFE) standards of 54.5 mpg by 2025 presents auto makers with a challenge over the next 10 years. The most promising technologies currently available for meeting high fuel economy and low emissions regulations are increased hybridization, turbo downsizing, and increased Diesel engine implementation. Combining these into a hybrid turbo Diesel is an ideal transition technology for the very near future as battery and other alternative fuels become viable for widespread automotive use. This paper presents a Diesel emission test stand to improve Selective Catalytic Reduction (SCR) systems for light duty Diesel vehicles, particularly hybrid power systems that experience many start-stop events. Advanced modeling and control systems for SCR systems will further reduce tailpipe emissions below existing Tier structures and will prepare manufacturers to meet increasingly stringent Tier 3 standards beginning in 2017. SCR reduces oxides of Nitrogen, NO, and NO2, from otherwise untreated Diesel emissions. Scientific study has proved that inhaling this harmful exhaust gas is directly responsible for some forms of lung cancer and a variety of other respiratory diseases. In addition to EPA Tier emissions levels and CAFÉ standards, the On-Board Diagnostics (OBD) regulations require every vehicle’s emission control systems to actively report their status during all engine-on vehicle operation. Testing and development with production NOx sensors and production SCR components is critical to improving NOx reduction and for OEMs to meeting strict Tier 3 light duty emission standards. The test stand was designed for straightforward access to the NOx sensors, injector, pump and all exhaust components. A Diesel Particulate Filter (DPF) followed by a Diesel Oxidizing Catalyst (DOC) precedes the Selective Catalytic Reducer (SCR) injector, mixing pipe and catalyst. An upstream NOx sensor reads engine-out NOx and the downstream NOx sensor reports the post catalyst NOx levels. Custom fabrication work was required to integrate the SCR mechanical components into a simple system with exhaust components easily accessible in a repeatable, controlled laboratory environment. A Diesel generator was used in combination with a custom designed resistive load bank to provide variable NOx emissions according to the EPA drive cycles. A production exhaust temperature sensor was calibrated and integrated into the software test manager. Production automotive NOx sensors and SCR injector, pump and heaters were mounted on a production light duty vehicle exhaust system. The normalized nature of NOx concentration in parts per million (ppm) allows the small Diesel generator to adequately represent larger Diesels for controls development purposes. Both signal level and power electronics were designed and tested to operate the SCR pump, injector, and three Diesel Exhaust Fluid (DEF) heating elements. An Arduino-based Controller Area Network (CAN) communications network read the NOx Diesel emissions messages from the upstream and downstream sensors. The pump, injector, solenoid, and line heaters all functioned properly during DEF fluid injection. CAN and standard serial communications were used for Arduino and Matlab/Simulink based control and data logging software. Initial testing demonstrated partial and full NOx reduction. Overspray saturated the catalyst and demonstrated the production NOx sensor’s cross-sensitivity to ammonia. The ammonia was indistinguishable from NOx during saturation and motivates incorporation of a separate ammonia sensor.


DYNA ◽  
2020 ◽  
Vol 87 (212) ◽  
pp. 47-56
Author(s):  
Juan Carlos Castillo Herrera ◽  
Juan Camilo López Restrepo ◽  
David Andrés Serrato Tobón ◽  
Juan Esteban Tibaquirá Giraldo ◽  
Sergio Andrés Carvajal Perdomo

In this study, a methodology to measure fuel consumption for light duty vehicles (LDV) in Colombia was elaborated based on existing methodologies from road transportation worldwide. This methodology was proposed as a tool for the evaluation of energy efficiency strategies applied to vehicles, as well as establishing the baseline for measurement, control, and regulation of consumption of fossil fuels based on metrological criteria. Additionally, the capacities for measurement within Colombia were analyzed, and procedures stated by the Code of Federal Regulations of the United States of America were adopted for measuring fuel consumption of LDV by gravimetric methods. An uncertainty model based on the Guide to the expression of Uncertainty in Measurement (GUM) was elaborated, and the contribution of different variables associated to the measurement process the instruments, the equipment, and the ambient conditions over the uncertainty of the measurand, were analyzed.


2017 ◽  
Vol 10 (4) ◽  
pp. 1580-1587 ◽  
Author(s):  
Krishna Chilumukuru ◽  
Aniket Gupta ◽  
Michael Ruth ◽  
Michael Cunningham ◽  
Govindarajan Kothandaraman ◽  
...  

Symmetry ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 1237 ◽  
Author(s):  
Moo-Yeon Lee ◽  
Kunal Sandip Garud ◽  
Han-Byeol Jeon ◽  
Ho-Seong Lee

One of barriers for the present heat pump system’s application in an electric vehicle was decreased performance under cold ambient conditions due to the lack of evaporating heat source. In order to improve the heat pump’s performance, a high-pressure side chiller was additionally installed, and the tested heat pump system was modified with respect to refrigerant flow direction along with operating modes. In the present work, the performance characteristics of the heat pump system with a high-pressure side chiller for light-duty commercial electric vehicles were studied experimentally under hot and cold ambient conditions, reflecting real road driving. The high-pressure side chiller was located after the electric compressor so that the highest refrigerant temperature transferred the heat to the coolant. The controlled coolant with discharged refrigerant from the electric compressor was used to heat up the cabin, transferring heat to the inlet air like the internal combustion engine vehicle’s heating system, except with unused engine waste heat. In the cooling mode, for the exterior air temperature of 35 °C and interior air temperature of 25 °C, cooling performance along with the compressor speed showed that the system efficiency decreased by 16.4% on average, the cooling capacity increased by 8.0% on average and the compressor work increased by 27% on average. In heating mode, at the exterior and interior air temperature of −6.7 °C, compressor speed and coolant temperature variation with steady conditions were tested with respect to heating performance. In transient mode, to increase coolant temperature with a closed loop from −6.7 °C, tested system characteristics were studied along the compressor speed with respect to heating up the cabin. As the inlet air of the HVAC was maintained at −6.7 °C, even though the heat-up rate of the cabin room was a little slow, the cabin temperature reached 20 °C within 50 min and the temperature difference with the ambient air attained 28.7 °C.


1976 ◽  
Author(s):  
J. W. Marzeski ◽  
W. S. Blazowski

Recent investigations have indicated that aircraft engine exhaust emissions are sensitive to ambient conditions. This paper reports on combustor rig testing intended to evaluate variations due to ambient temperature and pressure with special emphasis on idle engine operating conditions. Empirically determined CO, CxHy, and NOx correction factors — the ratio of the pollutant emission index value obtained during standard day operation to that resulting during actual ambient conditions — are presented. The effects of engine idle cycle pressure ratio, primary zone fuel-air ratio, and fuel type were investigated. Ambient temperature variations were seen to cause substantial emission changes; correction factors in excess of 2.0 were determined in some cases. Ambient pressure variations were found to be less substantial. A previously published NOx emission model and a simplified hydrocarbon combustion analysis are shown to be in general agreement with the empirical results.


Author(s):  
Allan J. Volponi

The various parameters appearing along an engine’s gas path, such as flows, pressures, temperatures, speeds, etc., vary not only with power condition but also with the ambient conditions at the engine’s inlet. Since a change in inlet temperature and/or pressure will contribute to an attendant change in a gas path parameter’s value, it would be difficult to characterize the aero-thermodynamic relationships between gas turbine engine parameters, (even at a constant engine operating point) unless the ambient conditions are somehow accounted for. This is usually accomplished through the use of corrected engine parameters. Although most of these corrections are well known by practitioners in the industry, knowledge of their origin does not appear to be as commonplace. The purpose of this paper is to fill that gap and furnish a summary of the commonly used corrections for the “major” gas path parameters that are used in performance analysis, diagnostics and control design, and to offer a derivation of these corrections. We will suggest both an analytic approach as well as an empirical approach. The latter can be used to establish the correction for parameters not directly addressed in this paper, as well as to fine tune the correction factors when actual engine data is available.


1978 ◽  
Author(s):  
D. H. Lister ◽  
M. I. Wedlock

Emmission measurements of carbon monoxide (CO), hydrocarbons (HC), and oxides of nitrogen (NOx) have been carried out on 12 Pratt and Whitney JT9D-7 turbofan engines after overhaul, and the effect of ambient conditions and engine to engine variation has been examined. Semi-theoretical correction factors, based on combustor inlet conditions, have also been applied to the data and a reduction in data scatter of better than 50 percent has been demonstrated. Average EPAPs for CO, HC, and NOx, have been determined: these are 13.9, 5.9, and 5.3 and bear a close relationship to other published data. Tests using both a fully thermostatted (423 K) or an uncooled probe have shown no observable differences in the measured emission levels.


1999 ◽  
Vol 121 (4) ◽  
pp. 613-621 ◽  
Author(s):  
A. J. Volponi

The various parameters appearing along an engine’s gas path, such as flows, pressures, temperatures, speeds, etc., not only vary with power condition but also with the ambient conditions at the engine’s inlet. Since a change in inlet temperature and/or pressure will contribute to an attendant change in a gas path parameter’s value, it would be difficult to characterize the aero-thermodynamic relationships between gas turbine engine parameters, (even at a constant engine operating point) unless the ambient conditions are somehow accounted for. This is usually accomplished through the use of corrected engine parameters. Although most of these corrections are well known by practitioners in the industry, knowledge of their origin does not appear to be as commonplace. The purpose of this paper is to fill that gap and furnish a summary of the commonly used corrections for the “major” gas path parameters that are used in performance analysis, diagnostics, and control design, and to offer a derivation of these corrections. We will suggest both an analytic approach as well as an empirical approach. The latter can be used to establish the correction for parameters not directly addressed in this paper, as well as to fine tune the correction factors when actual engine data is available.


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