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To clarify my above post, my laptop has 2GB video RAM and 32GB system RAM.

Hello, I hope someone here is able to help give me a definitive answer to my queries. Fluent 14.5 has support for utilizing a supported NVIDIA GPUs to off-load some computation tasks from the CPU with an HPC License (which my institution has). What is not clear from the literature I've read is...

I played around with the example file kindly provided by JohnRBaker (thank you!). I changed the law function because that in the example has a constant pitch between loops, i.e. an Archimedean rather than a logarithmic spiral (e.g. nautilis shell, hurricanes, etc.) that whose pitch get...

John, that appears to be it, thank you!! I'm trying to understand how you created it using a law spline (unexpected, but makes sense with the benefit of hindsight). I'm reading up some more on the logarithmic spiral function. Seems there are a couple of different forms in cartesian...

7.5. I also made up an Excel sheet where I can vary the parameters and visualize the results out of an X-Y table. Regards, Dave.

Hello all, I hope someone will be able to help me with this. I want to create a parametric curve of a 2D logarithmic spiral, ultimately to create an extruded body out of it. The equation of this curve is given by: In polar coordinates: r = a*e^(b*theta) or theta = (1/b)*ln(r/a)...

BrianPetersen wrote: Regarding cam timing effects, a lot of the muscle-car engines back in the day, and sport motorcycle engines nowadays, get away with 13:1-ish nominal compression ratio simply because they are running so much cam that at lower revs, the volumetric efficiency is lower, so there...

Retarded IVC need not experience a loss in performance (at least compared in magnitude to having to drop x PSI of boost and y degrees of ignition timing on account of knocking). If the intake is properly tuned, the charge backflow from late IVC can be minimized or eliminated where an...

A couple of things you can try to mitigate knock before opening the engine up to reduce the CR. First, 11.6 AFR is extremely rich; that's equivalent to about Lambda 0.79 on gasoline. Further, I assume that you are calculating AFR based on gasoline only. Methanol has a very different...

"6. One may wonder if two sequential VGT's will be an ultimate answer." Being done: http://forums.tdiclub.com/showthread.php?t=270527

Franz, I'm using GDI Injectors but placing them in the intake ports... I thought this was amply clear. We're thinking outside the box, this is not for a passenger car engine application.

GE-Jenbacher stationary gas engine.

"A thermodynamic cycle doesn't dictate the mechanism." -Agreed.

Draw a P-v diagram and you will see how expansion is longer than compression (the latter of which is to include the pre-expansion), which is the intent of the Atkinson -- and Miller -- cycle. Better, find the MTZ article I cited; it will even illustrate the P-v diagram for you.

In the above reference, the authors use EIVC as Miller and LIVC as Atkinson. Mazda uses the term Miller to denote LIVC with supercharging; Toyota uses Atkinson to denote LIVC in the naturally aspirated Prius engine. You can see that there's no real agreement on the nomenclature convention. A...

You don't have to agree with me, you just need to read some scholarly work on the subject for yourself: Schutting, E. et al. Miller- and Atkinson-Cycle on a Turbocharged Diesel Engine. MTZ 06I2007 Volume 68.

"Some hand calculations and common design sense will suffice to give 95% of the result of a PROPERLY done CFD-developed and -optimised model." The corollary to the above is that an improperly/poorly done CFD-developed manifold could wind up performing worse than the old-fashioned calculation...

There's plenty of disagreement even in engine circles regarding the distinction between the Miller and Atkinson cycles but they ultimately achieve much the same thing and some even (mistakenly) use the terms interchangeably. The thermodynamic cycles when plotted on P-v and T-S diagrams and the...

One can use a super-duper CFD program to design an intake manifold and then commit an epic fail as I witnessed recently: The offender proudly showed fancy screenshots showing streamlines of his manifold design. The fail occurred because he assumed air would be drawing through all 4 cylinders...

BMW's HP-DI with Valvetronic does not have a conventional butterfly throttle. Valve timing meters the amount of air that goes into the engine. This system runs lambda 1 to be compatible with a 3-way catalyst (TWC). VW/Audi (T-)FSI has a throttle and also runs at lambda one with a TWC. Ditto...