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GRT, flow matching nozzles, and the power of integrated vendors

Kahuna

Moderatoring
About 7 years ago I did an article on flow matching fuel injection nozzles. It has received a lot of attention over the years. Many have referred to it. Flow matching is simply getting your injectors matched IN THE PLANE during normal operations. I wont go into the details of that, its been written about extensively and included in the article above.
Back then about the best we had was an engine monitor that had the data, you just had to write it down, or download it & get it into a spreadsheet. Then it took some excel skills to get then information you needed.

Fast forward to today. I removed my AFS engine monitor and went to a GRT EIS and EFIS integration a few months back. One of the many things companies struggle with is, what do I do myself, and what can others do better. There is a cool FREE service on the web called SavvyAnalysis. They take your data file that you upload, and present it in a way that even an idiot can understand graphically. This only happens due to 2 companies getting together and sharing information.

So I take a recording of my GRT data while leaning the motor. A simple couple of buttons to record a demo file while flying and a USB stick in the panel. Come home. Throw the stick in the computer, Jump on a web browser, upload it to SavvyAnalysis, and whammo, I get this cool plotting diagram.
EISPlot.PNG


Taking this data, I noticed I now have a .5gph spread across the nozzles at peak. It was .1gph 1500 engine hours and 7 years ago. No idea why, but Ill figure it out and deal with it. Not the point of this message.

The point of this message is how we get to use the cool systems we have, some technology on the web, and some companies getting together to bring a very useful tool to us.

You want to play with this yourself? You can. Go to www.savvyanalysis.com, create your free account. Create your plane and profile, Grab my GRTDemoFile and save it locally to your computer. Then upload the file to Savvy and preview it. You can play with all kinds of stuff they have and see what it does. Pretty neat stuff. Enjoy
 
That's cool!

Thanks for sharing your log file, Kahuna. That's pretty neat stuff. I would have used Savvy Analysis a lot if I'd have known about it when I used to do test flying for Jabiru and Arion. It looks like it would beat writing EGT & CHT numbers on a note pad and taking photos of the EIS/EFIS engine graphs! :eek:
 
I'm totally with you on the advantages of keeping track of your injector balance as you lean. It's why the Dynon EMS systems show you the flow spread from first to peak vs last to peak every time you lean, right on the screen (and have since 2006).

Also, as a general note, SavvyAnalysis supports GRT, Dynon, AFS, and Garmin, so this is not a capability limited to only GRT users.

--Ian Jordan
Dynon Avionics
 
Taking this data, I noticed I now have a .5gph spread across the nozzles at peak. It was .1gph 1500 engine hours and 7 years ago. No idea why, but Ill figure it out and deal with it. Not the point of this message.

You dog.....ya can't throw that up there and expect us to ignore it ;)

Still have the 0.1 spread across five of the six. Got a best guess about that one cylinder peaking late?
 
Dan,
You can swap nozzles and see if it tracks the nozzle or the cylinder. This will tell you if it's a nozzle issue or something else like limited airflow to the cylinder, excessive backpressure, etc.

--Ian
 
It's why the Dynon EMS systems show you the flow spread from first to peak vs last to peak every time you lean, right on the screen (and have since 2006).
Yes, this is great information on the Dynon engine monitor. It is real time and very useful when running LOP with my carbed engine.
I have been using Mike Busch's Savvy Analysis with the Dynon engine log since it became available. Thanks to Mike Busch and Dynon.
 
You dog.....ya can't throw that up there and expect us to ignore it ;)

Still have the 0.1 spread across five of the six. Got a best guess about that one cylinder peaking late?

No not really. And when I took this recording I was just playing around. 3k', 18"mp loafing around etc. Was not dong it to actually log LOP flowing. Im gonna go do a controlled test for that purpose and capture a few times and see what I have. It does raise questions that needs answers. right now I dont even have a clue. My head is full answers of why cly's get leaner, but thoughts around richer elude me right now.
 
Savvy is a great product

Just a couple of nights ago I downloaded data from SkyView (can do that now) and uploaded it to Savvy and worked through the manual. What a great tool! Very friendly, very powerful, and it helped me compare several flights quickly to see what had changed.
 
Oh, this is so awesome and thanks for sharing. I am going to get a new demo today/tomorrow to see where my spread is in relation to FF. I did my injectors the manual way (writing it in a spreadsheet) and sending it to Don and he came up with a minor mod to two of the injectors.

Cheers
 
Nice tool. I'll surely try it out.

BTW, I'm willing to bet a beer at SnF that at your chart is showing a flow divider effect. :)
 
The Savvy program looks pretty good, I've been using EGView, the software that comes with the Electronics International equipment. It makes it very convenient to look at all engine parameters. You can add/subtract any engine parameter you like for clarity. This chart just shows EGT and FF to keep it simple.

egt.jpg
 
Not so fast there, Slim

Hey Kahuna

Ya gotta run the test at some particular power setting each time. Varying the MP or RPM will afffect the readings. I suggest the cruise setting, or as close as you can get.
Then, once tuned, you need to operate at the test setting. Other settings are not likely to work.
As you know, I run the 550, FYI it's inlet system is designed for 2500RPM. In addition, my engine is their "Platinum' version, with factory tuned injectors to match the tuned injection inlet system. GAMI not needed in this case.
This sytem does not work at my normal 2200RPM cruise setting.
So, I asked TCM about re-jetting for 2200RPM.
I was told 'sure it is possible, but watch out at full power!' I took that to mean over limit CHTs. Not good.
So, the tuning differences appeared re: differing RMP/MP settings. Full power, or design point, numbers would be compromised if I tuned for cruise.
Dang.
I opted for the better match at the design point (it IS spot on), and I will accept the weird numers at cruise. Oh well.
Might be that you, and other tuners, need to make the same choice? Dunno!!

EFI would solve this issue without blinking. Argh.

I am not of the opinion that I could design a better intake system, which would work at a wider RPM range. Maybe wide enough for my mission profile? Nah...

For your engine, Barrett makes the intake system you WANT, if LOP OPS are your intent. Rhonda will explain it. The Lyc setup is...less than optimal.

I'm not helpin' much, am I? Well, unless you need a lighter wallet...

Carry on!
Mark
 
Fuel Flow low?

This will probably be an incredibly, obvious, stupid question once I ask it, but are your FF's right? The header says you are running an IO-540? And the graph does show 6 EGTs. And it is peaking in the 10 GPH range. That seems way low. The IO-540 in our Lance will peak out around 15 GPH at low altitudes.

Am I missing something?

Gordon
Lancair ES N144GP flying
IO-550
 
No not really. And when I took this recording I was just playing around. 3k', 18"mp loafing around etc. Was not dong it to actually log LOP flowing. Im gonna go do a controlled test for that purpose

Good point. Mark and Bill both say it from different angles...the spread you have here may not be anything like the spread at the power setting you used when originally tuning the system.
 
Several tests and captures yesterday cruise settings. Still have the #4 way out. Scratching my head as to why. Test ranged from +.4gph to +.7gph richer than the rest.
 
Mike
I wonder if you have cleaned the injectors recently?

Gordon
Regarding the 10gph setting: With my 540 I regularly see 10gph when running lean of peak in the 55 to 60% power range.
 
Several tests and captures yesterday cruise settings. Still have the #4 way out. Scratching my head as to why. Test ranged from +.4gph to +.7gph richer than the rest.

Well, I guess I'm out a beer. ;) I was banking on the 18" MP and lower fuel flow to have you in a different spot on the flow divider openings. I expected the imbalance to disappear when you were back at normal ops.

I popped it out there because after one round of injector balancing, I am seeing what I believe is some flow divider effects on my engine.
 
Well, I guess I'm out a beer. ;) I was banking on the 18" MP and lower fuel flow to have you in a different spot on the flow divider openings. I expected the imbalance to disappear when you were back at normal ops.

I popped it out there because after one round of injector balancing, I am seeing what I believe is some flow divider effects on my engine.

Yes I believe you are out a beer.
This link may work. After getting to page, click the little GAMI button to get a better representation of the graph.
 
Oh sorry. If all you want is a capture of the screen and are not interested in posting it here, it depends on your platform and versions. If you on win 7 or higher (not basic version), there is a built in snipping tool. DO a win search on your system for snipping tool.
As for prtscrn. To capture a screen shot of the entire screen to the clipboard, press the PrintScrn key. To capture a screen shot of the active window or dialog box (for example, the WordPad application window or the File Open dialog box), press ALT+PRINTSCRN.
 
Oh sorry. If all you want is a capture of the screen and are not interested in posting it here, it depends on your platform and versions. If you on win 7 or higher (not basic version), there is a built in snipping tool. DO a win search on your system for snipping tool.
As for prtscrn. To capture a screen shot of the entire screen to the clipboard, press the PrintScrn key. To capture a screen shot of the active window or dialog box (for example, the WordPad application window or the File Open dialog box), press ALT+PRINTSCRN.

Thank you so much, now I have learned two things for the price of one :)

Here is my graph from the flight today.


EGT-FF by bavafa1, on Flickr
 
Yes I believe you are out a beer.
This link may work. After getting to page, click the little GAMI button to get a better representation of the graph.

Could be my 'puter or ISP but Savvy never finished loading your file for me to look at. Tried it a couple of times and let it run for a while too.

'sokay, don't really need to see it. I look forward to trying this with one of my downloads after I finish my condition inspection (stripping the panels now).
 
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