Showing papers in "SAE transactions in 1992"

Exhaust Gas Ignition (EGI) - A New Concept for Rapid Light-Off of Automotive Exhaust Catalyst

Abstract: Increasing pressure on lowering vehicle exhaust emissions to meet stringent California and Federal 1993/1994 TLEV emission standards of 0125 gpm NMOG, 34 gpm CO and 04 gpm NOx and future ULEV emission standards of 004 gpm NMOG, 17 gpm CO and 02 gpm NOx has focused specific attention on the cold start characteristics of the vehicle's emission system, especially the catalytic converter From test data it is evident that the major portion of the total HC and CO emissions occur within the first two minutes of the driving cycle while the catalyst is heating up to operating temperature The use of an electrically heated catalyst (EHC) has been proposed to alleviate this problem but the cost and weight penalties are high and the durability has yet to be fully demonstrated (1)* This paper describes a method of reducing the light-off time of the catalytic converter to less than 20 seconds by means of an afterburner The system uses exhaust gases from the engine calibrated to run rich and additional air injected into the exhaust gas stream to form a combustible mixture The key feature concerns the method of making this combustible mixture ignitable within 2 seconds from starting the engine when the exhaust gases arriving at the afterburner are cold and essentially non-reacting © Copyright 1992 Society of Automotive Engineers, Inc

Comparisons of computed and measured three-dimensional velocity fields in a motored two-stroke engine

Abstract: Computer simulations are compared with measurements of the three-dimensional, unsteady scavenging flows of a motored two-stroke engine. Laser Doppler velocimetry measurements were made on a modified Suzuki DT-85 ported engine. Calculations were performed using KIVA-3, a computer program that efficiently solves the intake and exhaust port flows along with those in the cylinder. Measured and computed cylinder pressures and velocities are compared. Pressures agree well over the cycle as do the velocities at the intake ports. In-cylinder velocities differ in detail, but the tumbling motion in the cylinder is well replicated in vertical plane passing through the cylinder axis. 20 refs., 7 figs., 3 tabs.

Advanced emission speciation methodologies for the auto/oil air quality improvement research program. I: Hydrocarbons and ethers

Abstract: An analytical method for the determination of hydrocarbon and ether emissions from gasoline-, methanol-, and flexible-fueled vehicles is described. This method was used in Phase I of the Auto/Oil Air Quality Improvement Research Program to provide emissions data for various vehicles using individual reformulated gasolines and alternate fuels. These data would then be used for air modeling studies. Emission samples for tailpipe, evaporative, and running loss were collected in Tedlar bags. Gas chromatographic analysis of the emissions samples included 140 components (hydrocarbons, ethers, alcohols and aldehydes) between C1 and C12 in a single analysis of 54-minutes duration. Standardization, quality control procedures, and inter-laboratory comparisons developed and completed as part of this program are also described. (Copyright (c) 1992 Society of Automotive Engineers, Inc.).

The Measurement and Analysis of Swirl in Steady Flow

Abstract: The influence of swirl on combustion in diesel and spark ignition engines is reviewed briefly, and this leads to a resume of the swirl measuring techniques. The numerous ways of analysing swirl data are summarised and the relations between the different swirl parameters are presented. Experimental results are presented from a diesel engine in which the flow has been measured by a hot wire anemometer, a paddle wheel and a swirl torquemeter. The performance of the different measurement techniques is compared. Further results are presented (from a spark ignition engine) which illustrate the influence of the inlet port, manifold and entry conditions on the swirl measurements. Integration techniques are reviewed for producing a single swirl parameter to characterise the combined performance of the inlet port, valve and camshaft. Finally, the difficulty in standardising measurements of barrel swirl are discussed. © Copyright 1992 Society of Automotive Engineers, Inc.