Tailpipe control

Since these emissions are not controlled or limited within the cleaning machine, treatment of them is called "tailpipe" control. 

Tends to burn visually cleaner at the exliaust tailpipe, since it operates in a closed-loop electronic mode (oxygen sensors interacting with the powertrain control module) to maintain an ideal air/fucl ratio of 14.7 1. 

Exhaust system The engine operating mode controls the tailpipe emissions of hydrocarbons (HC) and carbon monoxide (CO). Over 80% of HC and CO emissions are generated during cold-start and warm-up due to incomplete combustion. Fuel vaporization and fuel/ air mixing are important factors in achieving thorough combustion of the hydrocarbons. 

Tailpipe emissions of HC and CO are affected by the levels of heavy aromatics in gasoline. Like sulfur, the heavy aromatics are in the back end of the boiling range (Figure 10-4). As with sulfur, reduction of end point directly controls the concentration of heavy aromatics in finished gasoline. 

There is currently no air quality regulation in Europe or any other part of the world to control the ambient concentrations of particles on a number basis. However, particle numbers are currently being regulated at vehicle tailpipe exhausts through Euro-5 and Euro-6 emission standards [103]. These are the first ever limits of this kind, though only applicable in Europe, to control the emissions of particle numbers at source. These standards include a lower size limit of 23 nm for minimising the... 

Black FM, High LE, Lang JM. 1980. Composition of automobile evaporative and tailpipe hydrocarbon emissions. J Air Pollut Control Assoc 30 1216-1221. 

Figure 5 Effect of engine control on tailpipe emissions A well-calibrated gasoline engine results in significantly lower emissions after the catalyst (A) than does the vehicle with a poor engine calibration (B)...

Table 18. Engine-out and tailpipe emissions of a passenger car equipped with a closed-loop three-way emission control catalyst in the three phases of the US-FTP 75 vehicle test cycle (engine aged catalyst).

Chemical sensors are key in the transportation industry. Sensors are used to determine the fuel ratio, manage the optimum ratio, and measure the oil quality for pollution control. Chemical sensors monitor tailpipe emissions and catalytic converters. Additionally, sensors aid in chemical diagnostics of oil, transmission fluids, and other performance fluids. 

An NG vehicle can run eitlier near tlie stoichiometric point, or under fuel-lean conditions, due to its wide ignition range. If the vehicle is nm near the stoichiometric point, optimum conversion of methane is obtained mider slightly rich conditions. Rumiing the engine under fiiel-lean conditions provides better fuel economy and lower CO and NOx emissions [7]. Adequate NOx reduction luider fliel lean conditions is not yet practical, so tailpipe NOx emissions are likely to be lower with operation near the stoichiometric point. This study primarily focused on controlling emissions from vehicles running near the stoichiometric point, which is where conventional tliree-way catalysts will be the most useflil. 

The composition and quantity of the particles emitted from motor vehicles could be determined by direct and indirect methods. The most widely used methods for evaluating vehicle tailpipe emissions are dynamometer tests, which involve measurements of emissions from selected vehicles using standardized driving cycles under controlled conditions. However, a key concern with these tests is that they do not fully represent real-world driving conditions and emissions. A number of studies reported that particulate emissions from motor vehicles operated under real-world conditions can be significantly different from the results obtained from dynamometer-based studies conducted in the laboratory (Fraser et al. 1999). 

Increased use of leaded gasoline in Canada may generate pressures to control automotive exhaust lead emissions, although there is no established health-based lead-in-air standard to serve as the basis for such control. If reduction of automotive lead emissions into the atmosphere should be required, controls should be placed on the amount of lead emitted from the tailpipe, similar to the manner by which gaseous emissions are controlled. Such action is more energy efficient than reducing the amount of lead used in gasoline. One effective way to control tailpipe lead emissions is the use of automotive exhaust lead trap that replaces the standard muffler (2). 

Black, F.M. High, C.E. and Lang, J.M. (1980) Composition of automobile evapourative and tailpipe hydrocarbon emissions. Journal of Air Pollut. Control Assoc., 16, 67. 

Our goal in this chapter is to understand how to determine reaction rates and to consider the factors that control these rates. What factors determine how rapidly food spoils, for instance, or how does one design a fast-setting material for dental fiUings What determines the rate at which steel rusts, or how can we remove hazardous pollutants in automobile exhaust before the exhaust leaves the tailpipe Although we will not address these specific questions, we will see that the rates of all chemical reactions are subject to the same principles. 

In this case, under FEREl the engineers had a derivative ethical responsibility to situate their design work in a broad socio-technical-environmental system context, for example, the driver + engine + HAC -l- sensor + ECC + fuel injectors H- emissions control equipment -I- tailpipe -l- natural environment -I- humans living in that natural environment system. That was the broad system context within which the new chips were going to function and within which they could (and did) have noteworthy harmful effects. 

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