Just what numbers are you talking about when you mention delaying exhaust valve opening as long as possible?
Beyond Bottom Dead Center? I'm not sure that would work very well.
What crankshaft angle do you think the exhaust valves open at present?
" the gearbox will be set up to reach a peak pressure early (~170Kpa @ 2000 rpm), then maintain that to redline (5200 rpm) at 2/3 throttle or more, but provide little boost at less than 1/3 throttle, with the boost going from no boost to full boost from 1/3 throttle to 2/3 throttle."...
"Just curious, how many pounds/min of exhaust gas is hitting the turbine blades with your 350?"
Assuming 1) the airflow into the engine is 24.5 pounds per minute, 2) there are no engine/exhaust leaks or engine blowby (although there will be), and 3) stoichometric combustion rules at an air/fuel...
Several observations. . . . .
First of all, unless you really have a huge car (maybe several times the size of your jumbo size hummer) your engine will not produce anywhere near 150 hp to cruise at 60 mph.
Second, the typical car (non-hybrid) at "cruise" at 60 mph is only perhaps at...
A couple of observations here. . . . .
Gas engine turbochargers and diesel engine turbochargers don't quite work the same.
First of all, a gasoline engine turbocharger really only functions when you put the "metal to the pedal". If the pedal isn't down to the metal, then the engine is...
Let me see if I can elevate the level of confusion here. . . .
With a turbocharger -- or for that matter any turbine -- The work is done by the heat energy. The pressure (difference) is what enables the turbine to do the work.
Example: We'll talk about the amount of energy produced by the...
It's not hard to do the math folks. You're brainstorm pencils out like this:
Assuming a 5 liter engine @ 3600 rpm:
Volume of intake air per second, throttle wide open: 150 liters, or 39.6 gallons.
Vol of air @ atmospheric pressure in a 5 gal tank @ 200 psi: 68 gallons.
Time to use up all...
In English the title is:
"Definition and characteristics of the thermodynamic loss angle of piston engines"
(from Babel translator)
I have no idea what they are talking about, but would be interested in what the "thermodynamic loss angle" is.
Do these cars have the same engine?
From the website you mentioned;
"The all-new Accord Hybrid utilizes the third-generation of Honda’s advanced Integrated Motor Assist (IMA) full hybrid system in combination with new Variable Cylinder Management (VCM) cylinder deactivation technology to...
As I read these responses one thought occurs. . .
It is sort of perverse, but it turns out the advantage of the hybrid engines is not so much that they increase gas mileage, but that they increase acceleration, and that allows smaller engines to be used in cars.
These cars use miniscule size...
Here's a somewhat general question I would like to toss out to the group.
What is the value of engine efficiency? Now I'm not talking about vague concepts here, but something a little more concrete.
If there was something that could be bolted on an existing engine that would increase fuel...
I agree with the good professors ruiminations.
The only thing I would add, is that he is addressing things that rapidly become very complicated.
For example:
He mentioned the use of a turbocharger and it's effects on volumetric efficency, which is all well and good. However, the exhaust...
Okay, class. Excellent question, Jaded. Pay attention now, because this will be covered on the test.
Several assumptions: 1) This is a gas engine we are talking about, 2) it is a four-cycle gas engine, 3) Combustion will be stochiometric and complete, 4) the compression ratio is about 10:1, 5)...
A couple of points here. . . . .
If you are injecting fuel (like in a diesel engine), then you don't have a HCCI engine.
Even with a very high air/fuel ratio, you will still have stoichometric combustion with diesel injection, where you won't with HCCI combustion.
There are several huge...
Mike wrote:
"Another way of building boost of the line is to completely cut fuel to one cylinder (or I suppose two on an 8 cylinder?). The system I am aware of that does this builds about 6 or 7 psi doing that. You could also cut the ignition to that cylinder, but then you are dumping lots of...
