where is Dana Lin Scott

[eddietude]

How can I get in contact with Mr Scott....

Why would you want to???

I believe he has a yahoo group now where he's misguiding uneducated and trusting souls into believing his self-proclaimed hype of being one of the "pioneers" in the VO world....

[tractorguyacb]

^^^^^ What HE Said ^^^^^

[LSchulz]

He's back, at least on Greasecar.

He even says he'll post here. DB - play nice...

[powdrluvr]

He is spreading propaganda all over Biodiesel.infopop.cc again. He emailed me last week, inviting me into a discussion on filling up people with oil on road trips. He just posted another article stating 230 degrees is now the optimum temp. I guess I will have to unconvert my perfectly running rig, or get more heat, because what he states is truth. Just joking, I take his articles as a pile of crap, wish he would have a website with pictures and proof of what he actually does, and quit misleading any newcomer to the world of veg. Who has time to spread all this propaganda without trying to benefit personally? If he would only show us proof, I might begin reading his articles, and posts again.

If you find him, take pictures. I wonder if he is wearing a red and white shirt, carrying a cane, and canteen, and surrounded by tons of other people. (where's waldo)

I still don't believe he even burns veg.

[veggiesub]

If you're trying to get close to the viscosity of diesel as well as minimize soot production, then he is correct. 230 is near optimal. However, he is also correct in stating that these temps introduce other problems in VO systems. The ideal temps stated in most forum discussions are actually minimum acceptable temperatures.

[DieselBurps]

Originally Posted by veggiesub

If you're trying to get close to the viscosity of diesel as well as minimize soot production, then he is correct. 230 is near optimal. However, he is also correct in stating that these temps introduce other problems in VO systems. The ideal temps stated in most forum discussions are actually minimum acceptable temperatures.

What we should probably focus on is spray patterns and burn rates. The WVO temperature doesn't matter as long as it sprays out from the injector like diesel and burns completely. Biodiesel is thicker than diesel usually and it still seems to work pretty well.

I'm pretty convinced that the temperature is a nice attribute for general consideration, but other factors are more important. The temperature goal is to approximate the flow of diesel so the spray pattern isn't compromised by larger droplets of fuel that do not combust completely. If the fuel is injected at a commonly considered "good" temperature of ~ 160 *F and the EGT is low (ie ~ 300 *F), the fuel is most likely not burning as completely as if the EGT was running at 800 *F. Even our host here will tell you that idling on WVO is not a good idea. Speaking with forum members that have had catastrophic failures, it seems that many of them drove their diesels like little old ladies - the exact opposite of how diesels need to be run. The folks that are a little more aggressive with the throttle foot and run their vehicles for extended intervals under load seem to have the best success in longevity.

[cgoodwin]

You are wrong. Temp determines the droplet size, cone length, completeness of combustion (due to intmacy of contact with o2), etc. The only other variable I'd ignition delay. Increased EGT means that you have a higher temp flame front resulting in more active thermal cracking and better combustion of the larger droplets. Idling on a more vkscious fuel is asking for problems but temp is very important.

[veggiesub]

My knowledge ends at my last statement. It seems that temps higher than we can achieve via coolant heating are optimal, but what we do is good enough.

[DieselBurps]

I wasn't trying to say that temperature was unimportant - just that it is the generic attribute used, not the only one. injector pressure and the aperture also impact the "droplet size, cone length, completeness of combustion". My mechanic was discussing with me the possibility of swapping out injectors to some that have more but smaller openings - to get a better spray out of WVO. I haven't done so yet, but it was an interesting discussion.

Another way of looking at it is perhaps 230 *F would work if you were idling at low EGT (ignoring the possible damage done to electronics at those high temperatures), while 150 *F would be adequate with 800 *F EGT.

[cgoodwin]

Have a read through some of the material I posted back in 05 relating to this issue, it quickly becomes clear that there are huge benefits in combustion efficiency as the VO temp increases, the gain relation to temp is at its steepest from ambient to about 180F, after that there are still gains but they become flatter requiring two to ten times the temp gain for the same efficiency gain and that continues all the way past 350F/176C.

If we look at the paper posted here we clearly see thsi born out in the data provided, it reflects that there are gains in efficiency between 167F/75C and 275F/135C but that theses gains are markedly low relating to the required 108F increase in fuel temp. This is the reason I shoot for 180F of fuel temp. Achieving this temp using the waste heat of the engine is possible utilizing multiple heat exchangers and requires no additional energy draining heat sources (electric heat loads the alternator using as much as 10hp).

I would be interested in ANY supporting research he or anyone has supporting an optimum temp of 230F or any other figure.

It is not so much smaller injectors that provide a gain in effeciency as it is controlling how much fuiel is delivered when. Since power in a diesel is metered by fuel rather than air, overfueling is how they accellerate - hence the cloud of black smoke. Ideally this overfueling would be limited to just before the smoke point and the timing retarded 2 deg. to allow for the increased ignition time of VO. In addition careful attention should be paid to spray angle in direct injected motors and quite a bit of research has shown that limiting spray angle to 12 deg. prevented fuel from spraying directly on the cylinder walls and coking the ring lands.