Post by StuartG on Oct 4, 2010 5:36:45 GMT 1
Here's one of those 'geography' emails from About.com
"From Matt Rosenberg, your Guide to Geography
Hi folks! Even though it's officially autumn, here in Los Angeles the city experienced its highest record high temperature last Monday of 113 degrees (45C). It was pretty warm."
This put me in mind of why we all have catalytic converters on our vehicles. As told at the time, Los Angeles is built in a 'bowl' formed by the surrounding countryside. The exhaust gases from their vehicles were not being dispersed by the wind, and was retained by the 'bowl'. This built up to unbearable proportions, exacerbated by strong sunlight, so it was decided to do something. As this country [UK] then exported vehicles to the US they had to abide by the ledgislation, and conform to the 'Californian Cycle' for vehicle emissions. Practically this meant closed fuel systems, where evaporating fuel from tanks, carburettors etc, had either to be absorbed by a device [usually a charcoal filled cylinder] or fed back to the engine in some way. Another example would be 'air injection' into the earlier [before silencer/muffler] part of the exhaust, of air, from a compressor mounted like the generator [dynamo or alternator, still new] on the engine. Closed engine breather systems and 'gulp' valves, 'capsules' to slow the closed throttle to idle when decelerating. The catalytic converter, meant a change to unleaded fuel [known then a 'weasel pee'] . All this without engine management systems.
The vehicles were driven through what was known as the 'Californian Cycle' a series of accelerations/decels and gear changes, to simulate urban driving, but on a rolling road [chassis dynamometer]. The exhaust gases were analysed and graphs drawn to show conformity [or not!].
Just thought You'd like to know...
Stuart
"From Matt Rosenberg, your Guide to Geography
Hi folks! Even though it's officially autumn, here in Los Angeles the city experienced its highest record high temperature last Monday of 113 degrees (45C). It was pretty warm."
This put me in mind of why we all have catalytic converters on our vehicles. As told at the time, Los Angeles is built in a 'bowl' formed by the surrounding countryside. The exhaust gases from their vehicles were not being dispersed by the wind, and was retained by the 'bowl'. This built up to unbearable proportions, exacerbated by strong sunlight, so it was decided to do something. As this country [UK] then exported vehicles to the US they had to abide by the ledgislation, and conform to the 'Californian Cycle' for vehicle emissions. Practically this meant closed fuel systems, where evaporating fuel from tanks, carburettors etc, had either to be absorbed by a device [usually a charcoal filled cylinder] or fed back to the engine in some way. Another example would be 'air injection' into the earlier [before silencer/muffler] part of the exhaust, of air, from a compressor mounted like the generator [dynamo or alternator, still new] on the engine. Closed engine breather systems and 'gulp' valves, 'capsules' to slow the closed throttle to idle when decelerating. The catalytic converter, meant a change to unleaded fuel [known then a 'weasel pee'] . All this without engine management systems.
The vehicles were driven through what was known as the 'Californian Cycle' a series of accelerations/decels and gear changes, to simulate urban driving, but on a rolling road [chassis dynamometer]. The exhaust gases were analysed and graphs drawn to show conformity [or not!].
Just thought You'd like to know...
Stuart