On Mon, 25 Dec 2006 14:54:31 -0800, Jerry Scharf wrote: > clearly this has been explored a great deal more than I understand. :)
Big boys toys, the ultimite "fallus" experience. :-) > I would doubt you will get much more information inside the turbo about > humidity than you will outside (no moisture coming or going there.) Uhmmm, I forgot to mention that the intake channel contains several water-spraying-nozzles... There's one in front of the turbo's air intake to cool the turbo and inside the air duct is the main water injection nozzle. The total amount of water injected is 30-50% of the fuel amount and is used as primairy coolant. (since the engine is running without cooling, except for the pistons wich are cooled with an oil-spray on the bottom) Another use of water is to cool down the intake air, the turbo wheel can heat that up to 300cel. and the evapurating water will extract heat. > You will want temperature and differential pressure in the turbo > environment. Thermocouple temperature sensors shouldn't care about the > nasty environment and you can do a j tube setup to keep the nasties away > from the pressure sensor. A type T for inlet air would also do (if it's cheaper) for exhaust I will probebly need a type N or a type K. > Set it up with the pair of counters. When you get ready to go, take an > initial reading with the engine stopped. Once this is stored, the counts > for each one will increment as they get falling pulses. So if the cam > reading is lower than the crank reading, the belt broke. If they are in > sync, the belt died after the fact. You really don't want to be trying > to count the pulses any other way. That sounds fine for damage control, but I still need a reading for engine rpm in the main log, when evaluating a run afterwards it's important to know the relationship between rpm, humidity, turbo-boost and temp. > I'm with Paul on this. Dump the data in raw form then fed that into rrd > as a second stage. You only have a minute or two of data. Your both right, dumping raw is bether but rrd was for me a way to workaround different polling times of the different sensors. (unless owfs contains time values for syncing the different signals) If rrd polls every 10ms. reading owfs all is in sync. (except for latency inside a sensor) >> The DS2450 should be great for temp and pressure > See my comments above. 2760 is defenatly fast enough. On Mon, 25 Dec 2006 15:22:13 +0100, Jan Kandziora wrote: > Are you really sure it works that way? I would expect the cambelt to jump a > few teeth in any case before you can measure any speed change in cambelt and > shafts. I didn't thought of that option, but must say that I never had seen it happen, mostly engines die because the pistons and/or rods leave the engine at unwanted places or the complete cylinderhead is blown of... http://www.japie.deserver.nl/ftp/Max_trouble.mpeg In will defenatly dive into it to find a way... > Second, instead of checking speed of the engines shafts, I would check gas > pressures to look for that situation. Gas pressure is directly joined with > the engine's current situation, so is torque (but torque is hard to measure), > speed in contrary is just a derived value. Your right, rotation speed isn't that important but it's one of the few things we see on the tracotr itself during a run. An rpm counter and a turbo-boost gauge are placed in visual sight and these 2 readings (plus our ears) are telling us when to release the clutch. If results of data-logging are telling us dat we do it wrong, we would like to know how to do it the next time so an rpm reading is important. (but theoraticly your right, it's the torque that counts) And torque is messurable, place on pulse counter on one end of the drive-axle and one on the other end and messure the "twist" between them, if you know the material strenght of that axle you can calculate the torque. On Mon, 25 Dec 2006 08:08:03 -0500, Paul Alfille wrote: > Is a stick fast enough? I suppose the OS will cache to RAM first. The wl-hdd has a usb-1.1 port but since it's only one it's shared by all sensors and the stick, actualy I have no idea but the used filesystem on the stick can mather. If using rrd I would leave it to vfat but for raw data maybe reiserfs would perfomr bether. As long as the bus speed is enough I setle. > Use the standard humifity sensor (DS2438-based) AAG used to make one in a > stainless steel enclosure that might be more appropriate for your use. I > have no idea of the effect of pressure or diesel fuel on the sensors. The diesel is injected directly in the cylinder so it won't come into contact with the sensors. Thanks all for the responce! -- Groetjes Japie ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys - and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Owfs-developers mailing list Owfs-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/owfs-developers
