\n~ Alex<\/p>\n
\u2014\u2014\u2014\u2014\u2014\u2014\u2014\u2014You\u2019re welcome, George.OK, I\u2019ve finally managed to grab some time & go through the book \u2013 here are my corrections for grammar\/spelling, suggestions & comments.\u00a0 Hope you find it useful.=================
\nCorrections:<\/p>\n
=======================<\/p>\n
On web site According to the AEVA in urban driving you need 130 Wh\/km, on the open road 150, and on the highway 210 (presumably as speed 60, 80, 100-110 kph and increased air resistance); when the traffic is heavy it\u2019s about 115 Wh\/km (40kph).\u00a0\u00a0Anyway, when we take these figures & realise that petrol contains 34.92 MJ\/L (US figures) => 9700 Wh\/L, if we use the \u201copen road\u201d figures we should be able to get 65 km\/L if the engine was as efficient as an electric motor.\u00a0 According to\u00a0http:\/\/www.engineeringtoolbox.com\/electrical-motor-efficiency-d_655.html<\/a>\u00a0the electric motor is around 90% efficient in a lab (I have my doubts; I\u2019m guessing in practise and when you take into account losses in the battery feeding out energy really quicker it\u2019d be under 80%), so that means the 100% efficient figure would be 75 km\/L (or more).\u00a0 As per\u00a0http:\/\/www.vangeyn.net\/mpg\/?km=75&submit=Convert<\/a>\u00a0that\u2019s 175 mpg (which we already know is an underestimation based on the Shell Opel results), or 125 mpg for when the car is travelling at 100 kph+ (60 mph). So, based on these figures we\u2019ve PROVEN based on real world figures that any decent modern petrol vehicle should be getting over 100mpg.<\/p>\n Peter______________\u00a0Thanks, George!<\/p>\n \u2026, it looks very well thought out, researched, and understandable.<\/p>","protected":false},"featured_media":0,"template":"","meta":{"_acf_changed":false},"product-resource-group":[103],"restricted-resource-tag":[],"class_list":["post-914","product-resource","type-product-resource","status-publish","hentry","product-resource-group-double-mileage-guaranteed-resources"],"acf":[],"_links":{"self":[{"href":"https:\/\/aquacure-jeffro-dev.linksdev.com\/es\/wp-json\/wp\/v2\/product-resource\/914","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/aquacure-jeffro-dev.linksdev.com\/es\/wp-json\/wp\/v2\/product-resource"}],"about":[{"href":"https:\/\/aquacure-jeffro-dev.linksdev.com\/es\/wp-json\/wp\/v2\/types\/product-resource"}],"wp:attachment":[{"href":"https:\/\/aquacure-jeffro-dev.linksdev.com\/es\/wp-json\/wp\/v2\/media?parent=914"}],"wp:term":[{"taxonomy":"product-resource-group","embeddable":true,"href":"https:\/\/aquacure-jeffro-dev.linksdev.com\/es\/wp-json\/wp\/v2\/product-resource-group?post=914"},{"taxonomy":"restricted-resource-tag","embeddable":true,"href":"https:\/\/aquacure-jeffro-dev.linksdev.com\/es\/wp-json\/wp\/v2\/restricted-resource-tag?post=914"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\n\u201cexplaination\u201d -> \u201cexplanation\u201d
\n=============
\nComments:10 \u2013 \u201cexcellent combustion\u201d \u2013 the exhaust having only 6% of fuel unburned is probably a massive underestimation as the paper doesn\u2019t say if the tests were of the exhaust gases AFTER or BEFORE the catalytic converter.\u00a0 As they mention taking measurements on one truck (which also makes the measurements suspect; they should have taken measurements from several vehicles and given the range) and do not mention a cat at all it would be safe to assume AFTER.\u00a0 The catalytic converter gets to incredibly high temperatures and as such would combust the majority of unburned hydrocarbons that reach it (As perhttp:\/\/www.academicjournals.org\/article\/article1380014872_Metwalley%20%20et%20al%20pdf.pdf<\/a>\u00a0nearly all of it in lab conditions with a brand new cat, see figures 18 & 27).\u00a0 So, to put it politely, I\u2019d say they f*ck*d up & the figures given are virtually worthless; the actual unburned HC straight out of the engine would be much higher.
\nAlso there is an implicit assumption that all the burned hydrocarbons contribute to motive power, which we know is not true \u2013 as it is a chemical process, it take some time for what can be quite long hydrocarbon chains to be broken down into individual carbon and hydrogen atoms which is required to combine with oxygen to form CO2, H2O and heat.\u00a0 Most of this happens AFTER the piston has expanded, ergo is wasted energy, which you address later in the book \u2013 even measuring the gas straight out of the engine is misleading because of this.
\nIn addition some of the energy is \u201cused\u201d to convert nitrogen in the air into various NOx species, which is the primary official reason for us having a catalytic converter, in order to break these down and prevent smog.
\n=============
\n27 \u2013 the HP required to propel a 1700 pound car with drag coefficient of 0.32 graph is misleading, with the line being a lot higher than it should be, especially at high speeds.\u00a0 Whilst it is true that most of the energy that goes into propelling a car forwards at low speeds (below about 40 mph) is due to friction caused by the mass of the car pushing the wheels into the road, above this speed the engine is having to spend more of its energy on fighting air resistance than it does on actually moving the vehicle.\u00a0 So at high speed the HP required has virtually nothing to do with the mass of the vehicle \u2013 it\u2019s all about the surface area of the car as viewed from the front (i.e. what the air is actually \u201chitting\u201d) and the shape which determines how much drag there is due to turbulence.\u00a0 The perfect shape is a raindrop on its side (i.e. nearly spherical front with long tail), as shown by this being the shape water automatically forms when falling through the atmosphere (and similarly why a sperm is the same shape, to minimise energy loss in its race of life).\u00a0 What we really need is for the people who came up with this graph do the same test but with the car in a vacuum \u2013 you\u2019d seal in the engine compartment & feed in air via a tube, then similarly have the exhaust going out another tube, & chuck the lot on a dyno and graph that.\u00a0 I\u2019d be betting you see the line go up to begin with & then nearly flatten out.
\nSo, as per\u00a0http:\/\/en.wikipedia.org\/wiki\/Drag_coefficient<\/a>, it\u2019s all about the shape and size of the vehicle that determines fuel consumption on the highway.
\nThe only energy you\u2019re spending that is related to the mass of the vehicle is that required to overcome static friction initially (ever noticed that it takes a bit of an effort to get something moving, but it gets a lot easier after it starts & then remains constant?\u00a0 That\u2019s due to static friction \u2013 electromagnetic bonds formed between the surface of the two objects when they\u2019re at rest), which as per F=ma is constant regardless of your velocity (as the mass of your car is constant, and the acceleration caused by gravity is constant), plus a bit due to friction between the tyres and the road, which is something you can cut with low friction tyres, but obviously not too much or else it\u2019s just like you\u2019re driving on ice.\u00a0 Notice how a car on ice can move very long distances even when the engine is turned off & brakes applied?\u00a0 That\u2019s even more evidence as to how little energy you need to keep a car moving once it\u2019s in motion, regardless of its mass.
\nSo, I\u2019d be a bit cautious about making claims that the 135 mpg Peugeot is achieving a thermal efficiency of 60% \u2013 I\u2019d be betting in reality that\u2019s 20-30%, maybe even less.\u00a0 It only stands to reason as well if the Opel was able to get 375 mpg; otherwise you\u2019d come to the conclusion that it was achieving a thermal efficiency of 375\/135*60=167% \u2013 yay, we\u2019ve achieved overunity!
\n=============Here\u2019s some additional ammunition you might like to include \u2013 I did these calculations a few years ago back when I was in CSIRO when I was writing an article on comparative efficiencies between petrol and electric vehicles. The AEVA (Australian Electric Vehicle Association) had several members who converted bog standard petrol cars into EVs by ripping out the engine, gearbox and fuel tank and replacing them with an electric motor & battery pack of a similar overall mass.\u00a0 They didn\u2019t make any optimisations like putting small electric motors in each of the wheels & using drive-by-wire which would allow them to save a fair bit of weight and friction by getting rid of the drive train, etc etc, so this means that in terms of energy requirements for distance travelled the vehicles are directly comparable with petrol vehicles on the road today (or a few years ago).\u00a0 As I\u2019m Australian I use metric, not those weird imperial units you guys use\u00a0![\"\ud83d\ude42\"](\"https:\/\/s.w.org\/images\/core\/emoji\/15.0.3\/svg\/1f642.svg\")
<\/p>\n
\nAn internal combustion engine is effectively a Carnot Cycle, if we believe the physicists (http:\/\/chemwiki.ucdavis.edu\/Physical_Chemistry\/Thermodynamics\/Thermodynamic_Cycles\/Carnot_Cycle<\/a>; although as you point out this ignores the work caused by the velocity, and thus pressure, of the explosion).\u00a0 As per\u00a0https:\/\/answers.yahoo.com\/question\/index?qid=20110527202032AAzE7uc<\/a>\u00a0we can get to around 2500K (or more) inside the piston, with standard conditions being around 300K.\u00a0 If we put these into
\nhttp:\/\/hyperphysics.phy-astr.gsu.edu\/hbase\/thermo\/carnot.html<\/a>then we get a maximum efficiency of 88% \u2013 so that means it SHOULD be possible to get the SAME efficiency in the petrol vehicle as we are in the EV.<\/p>\n