I have demonstrated why fundamentally(ideally, not worrying about realization) why zero exhaust gas in input charge is fundamentally sound. Please refer back to what I have written. Three separate write ups
As a result of trying to find the best operating condition to present my efficiency calculation, I have arrived at the following best operating conditions for Chen engine. I'll outline the three main points then go into detail
1. gas mixture non-stoichiometric, in fact highly lean
2. Thus we will not use three way converter for Chen engine. Just a NOx converter (three way converter requires stoichiometric combustion)
3. the direct fuel injection must be able to provide locally rich mixture for spark ignition. The fact that F1 can operate at 3-4 ATM, technology is here.
As I mentioned in my last posting, lean operation is the most fuel efficient. Chen engine is no exception. It will operate in this mode plus the exclusion of exhaust gas. As on each input cycle, there are already 1/10 atm of air, thus Chen engine control unit must admit just enough air for idling requirement. The conventional engine with normal exhaust air is 1/3 of ATM(21 inches of Hg of vacuum), thus we still need some input air. Conventional engine needs 33-10 = 22. Meaning it need 0.22 Atm amount of air into cylinder for conventional ignition. If we go to Chen engine and assuming efficiency improvement of 50% (need only half of the gas), then we allow about 0.01 atm amount of air in. With our direct fuel injection, this means during idle, the input valve can be closed, we rely only on the air from air injection. (This is for Stoichiometric operation, and ECU should admit more air for lean operation for energy saving(reducing pumping loss as well)
Thus, ECU will admit 0,1 atm of air for idle, so that it is 50% on the lean side of stoichoimetric.
For the rest of the operating range, rpm and load factor, ECU computer must calculate how much air is to be allowed in. Keeping in mind that the mixture must be lean, but at the same time good ignition. A well designed fuel injector and spark timing should allow very lean combustion.
The lean combustion of Chen engine also serves another purpose, the CO and HC are burned up completely before exhaust cycle. Thus, there is no need for Air injection to burn up the CO and HC, thus saving energy for the compressor. In deed, we need to purge out exhaust gas near TC, thus very minimal volume of air.
The reason Diesel does not emit CO and HC is that it operates always at lean(very lean) condition, hence the power and economy. (It has other problems like soots). In this way, thanks to modern day direct fuel injection, with air injection to totally purge out the exhaust fume in the cylinder, we can operate Chen engine in semi-Diesel fashion, with their economy, low end torque and free of CO and HC pollution.
This is what I claimed on the first posting and now I am explaining why. Thank you for following.
With operating conditions specified, my next post will be the fuel efficiency calculation based on this mode, and the next one will be compressor gas volume, power calculation. Then I am done.
Chengine
For me all these is work in progress. I worked everything out with you guys.
I have demonstrated why fundamentally(ideally, not worrying about realization) why zero exhaust gas in input charge is fundamentally sound. Please refer back to what I have written. Three separate write ups
As a result of trying to find the best operating condition to present my efficiency calculation, I have arrived at the following best operating conditions for Chen engine. I'll outline the three main points then go into detail
1. gas mixture non-stoichiometric, in fact highly lean
2. Thus we will not use three way converter for Chen engine. Just a NOx converter (three way converter requires stoichiometric combustion)
3. the direct fuel injection must be able to provide locally rich mixture for spark ignition. The fact that F1 can operate at 3-4 ATM, technology is here.
snip
3-way cat requires cycling between rich and lean to both reduce NOx and oxidize CO/HC
running lean will give you the same problems that diesels have, you'll need a to inject a catalyst like urea to reduce NOx
Chen engine will add efficiency to the stratefied engine. Thanks for being a little fair. Please read it more. If you guys do not even believe this configuration, I do not have anything better. I'll get the efficiency out, this is based on this configuration.
Here is the idling efficiency calculation based on the model I laid out earlier.
Major points: lean running, based on sophisticated direct injector that can work with spark plug to ignite lean mixture.
Air injector installed to replace top waste gas with air. And of course pollution device only NOx converter needed.
For the model, I use infinitesimal fuel and Stoichoimetric air to simply calculation, for finite fuel, required for powering the engine, it is just a multiplication factor. It may affect the calculation by very small amount.
Here we go: We just use the classic ICE efficiency formula that involves only gas capacity parameter and compression ratio.
For conventional engine the idle vacuum is 21 inches, 237 mm Hg absolute. The efficiency of this mixture is 24% when compressed 10 times. And all the "charge" is exhaust gas. And the pressure at ignition is 3 atm. Waste gas parameter in 1.25.
For Chen engine, we have very flexible combustion, with unlimited air and wide combustion range. Thus we start with 0.8 atm of air. Applying the same formula using air parameter of 1.3. The result is 48% efficiency, double that of current system
This means that the fuel required for the same work on the engine is halved from normal engine to Chen engine at idle.
This calculation is hypothetical. however, the range of efficiency improvement could be higher or lower depending on actual vacuum pressure of the manifold of normal system. Nonetheless 50% is a good number. This number has been assumed in most of this posting. Now it is proved.
η = 1 - (1/r^(γ-1))
η - efficiency
γ - heat capacity ratio
r- Compression ratio
For conventional engine the idle vacuum is 21 inches, 237 mm Hg absolute. The efficiency of this mixture is 24% when compressed 10 times. And all the "charge" is exhaust gas. And the pressure at ignition is 3 atm. Waste gas parameter in 1.25.
η = 1 - (1/r^(γ-1))
γ - 1.25
r- 10 η - 0.437
For Chen engine, we have very flexible combustion, with unlimited air and wide combustion range.
You have shown absolutley no evidence to support this. State why you think it's more flexible.
Thus we start with 0.8 atm of air. Applying the same formula using air parameter of 1.3. The result is 48% efficiency, double that of current system
η = 1 - (1/r^(γ-1))
γ - 1.3
r- 10 η - 0.49
This does not agree with your figures. Show your working of how you got to them.
I suspect I know what you’ve done. You've altered the compression ratio.
Compression ratio is defined by the geometry of the engine only! V2/V1
Filling x% the cylinder with exhaust gas DOES NOT ALTER COMPRESSION RATIO. Capped and bolded for extra impact. You may have (1-x)% fuel air charge but the other x%is exhaust gas, you are still compressing the cylinder contents by the same amount.
xxChrisxx wrote:
I suspect I know what you’ve done. You've altered the compression ratio.
Compression ratio is defined by the geometry of the engine only! V2/V1
Filling x% the cylinder with exhaust gas DOES NOT ALTER COMPRESSION RATIO. Capped and bolded for extra impact. You may have (1-x)% fuel air charge but the other x%is exhaust gas, you are still compressing the cylinder contents by the same amount.
I noticed that he seemed to have this misconception on page 1, probably should have said something back then because it seems to underscore much of what is wrong with his theory.
this chen engine would be fantastic in cheat the smog test. who needs a catalytic coverter? just inject some fresh air into the exhaust system and its all good
Powerslide wrote:this chen engine would be fantastic in cheat the smog test. who needs a catalytic coverter? just inject some fresh air into the exhaust system and its all good
With all the smog about, would the fresh air have to be imported?
Powerslide wrote:this chen engine would be fantastic in cheat the smog test. who needs a catalytic coverter? just inject some fresh air into the exhaust system and its all good
I don't know how the smog test works, but in the EURO type approvals it wouldn't help it is measured in absolute mass not concentration
and if you add air to the exhaust the three way cat won't work so you'd probably fail on NOx
