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Do new GDI engines have throttle plate?
- Thread starter moon161
- Start date
BrianPetersen
Mechanical
What commercial engines use the Miller cycle in turbocharged form?
High PR turbocharging implies a diesel application. I'm not aware of any production diesel engines that actually use the Miller cycle, although since it is only a camshaft profile change away, it's possible that it is present but not advertised as such.
High PR turbocharging implies a diesel application. I'm not aware of any production diesel engines that actually use the Miller cycle, although since it is only a camshaft profile change away, it's possible that it is present but not advertised as such.
TDI - despite much searching I still have yet to find the Schutting et al paper.
I am afraid I take a somewhat simplistic and less "scholarly" view of the Atkinson Cycle. I regard any engine which has a high CR (too high for "normal" use) combined with any strategy to reduce the combustion chamber pressure after compression as "Atkinson". Whether this strategy is LIVC, EIVC, automatic throttle plate control or any other method of limiting the pressure - it is still Atkinson.
I can see why you favour EIVC as being closest to "true" Atkinson but I think it still needs the CR component to be called Atkijnson.
Without the high CR component, LIVC and EIVC I think should be regarded as engine load control/reduced pumping loss strategies. I have found from personal experience that LIVC is more effective than EIVC.
The following is probably less "scholarly" than Schutting et al but I agree with their views - which I think are expressed very clearly.
I should point out that I have no connection with Mechadyne and I don't think that their variable valve strategies are very practical - but I like (and agree with) their explanations of the various part-load strategies.
I am afraid I take a somewhat simplistic and less "scholarly" view of the Atkinson Cycle. I regard any engine which has a high CR (too high for "normal" use) combined with any strategy to reduce the combustion chamber pressure after compression as "Atkinson". Whether this strategy is LIVC, EIVC, automatic throttle plate control or any other method of limiting the pressure - it is still Atkinson.
I can see why you favour EIVC as being closest to "true" Atkinson but I think it still needs the CR component to be called Atkijnson.
Without the high CR component, LIVC and EIVC I think should be regarded as engine load control/reduced pumping loss strategies. I have found from personal experience that LIVC is more effective than EIVC.
The following is probably less "scholarly" than Schutting et al but I agree with their views - which I think are expressed very clearly.
I should point out that I have no connection with Mechadyne and I don't think that their variable valve strategies are very practical - but I like (and agree with) their explanations of the various part-load strategies.
P-V diagram illustrates the differences.
Engineering is the art of creating things you need, from things you can get.
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