50k miles of alcohol injection and no cracked pistons! Cheap alky kits exposed.
Sep 22, 2010, 07:59 AM
#196
Some real world date on dribble.
I ran some alkycontrol kits that I installed. I kept the line from pump to nozzle as short as possible. Less than 20 inches for sure and maybe closer to about 14 inches. I would mount pump as close to I/C outlet as i could get it. And install nozzle at about 6 inches past the I/C out. Before BOV. This minimizes dribble as the whole line itself has to de-pressurize when pump shuts off. I also wanted max time in pipes for alky cooling to do its job.
I would do hard pulls and be stopped immediately at traffic lights. A/F at idle would be ~11.0. it would take 30-45 seconds to reach 14.7. very clear this was the dribble and wall wetting airing out in pipes and intake.
I dont have any data on how much is dribble and how much is wall wetting. I never ran any PWM sytems like aquamist. Would like to hear if anyone has similar observations to what I was seeing.
I ran some alkycontrol kits that I installed. I kept the line from pump to nozzle as short as possible. Less than 20 inches for sure and maybe closer to about 14 inches. I would mount pump as close to I/C outlet as i could get it. And install nozzle at about 6 inches past the I/C out. Before BOV. This minimizes dribble as the whole line itself has to de-pressurize when pump shuts off. I also wanted max time in pipes for alky cooling to do its job.
I would do hard pulls and be stopped immediately at traffic lights. A/F at idle would be ~11.0. it would take 30-45 seconds to reach 14.7. very clear this was the dribble and wall wetting airing out in pipes and intake.
I dont have any data on how much is dribble and how much is wall wetting. I never ran any PWM sytems like aquamist. Would like to hear if anyone has similar observations to what I was seeing.
Sep 22, 2010, 08:08 AM
#197
The new AEM Injection monitor is a flow based fail safe that has a flow sensor and an internal data logger. It took more time to annotate this picture than it did to gather the data. The pump pressure was set to a factory Aquatec setting of 200 psi. The injection monitors internal data-logger records every channel every 0.050 seconds (20 times a second). It creates standard AEM .stf data files and uses AEMLog to analyze the data, just like the AEM EMS. You can also overlay your Injection Monitor data files with your EMS internal or PC data logs.
What you are looking at:
The red line is actual measured flow in cc's/minute. it's flowing around 510cc/min on the left. Drops to zero when the pump is abruptly shut off and then goes back up to about 470cc/min by the end of the graph. The blue lines above and below the red line is the window boundaries for the fail-safe. If the flow went outside of those for more than the allowed time a failure is triggered. The black line is pump duty cycle. Anything over 85% or so is full on.
The pump is shut off at 24.750 seconds and the flow remains essentially unchanged until about 24.850 then falls dramatically to zero by 24.900. So the dribble time on an AEM water/meth kit is around 150 to 200 milliseconds (0.15-0.20 sec). Not half a second. Not a full second. Not 4.5 seconds.
As a quick reality check, the entire duration of the log shown in the window is only 1.6 seconds from the far left to the far right. After looking at this actual recorded data it is very easy to spot the problems with the graphs that were posted earlier and see why I called B.S. I have no idea what kind of WAI system was used to generate the log posted by Richard but I can only say that it in no way represents the current state of the art in PPS systems.
The internal data logger is another great reason the AEM Injection Monitor is the best water injection fail safe you can buy, because without data you're just another guy with an opinion.
What you are looking at:
The red line is actual measured flow in cc's/minute. it's flowing around 510cc/min on the left. Drops to zero when the pump is abruptly shut off and then goes back up to about 470cc/min by the end of the graph. The blue lines above and below the red line is the window boundaries for the fail-safe. If the flow went outside of those for more than the allowed time a failure is triggered. The black line is pump duty cycle. Anything over 85% or so is full on.
The pump is shut off at 24.750 seconds and the flow remains essentially unchanged until about 24.850 then falls dramatically to zero by 24.900. So the dribble time on an AEM water/meth kit is around 150 to 200 milliseconds (0.15-0.20 sec). Not half a second. Not a full second. Not 4.5 seconds.
As a quick reality check, the entire duration of the log shown in the window is only 1.6 seconds from the far left to the far right. After looking at this actual recorded data it is very easy to spot the problems with the graphs that were posted earlier and see why I called B.S. I have no idea what kind of WAI system was used to generate the log posted by Richard but I can only say that it in no way represents the current state of the art in PPS systems.
The internal data logger is another great reason the AEM Injection Monitor is the best water injection fail safe you can buy, because without data you're just another guy with an opinion.
Sep 22, 2010, 09:39 AM
#198
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This is exactly what I thought too, looking at the log in post #169.
The AEM log in post #188 is, I would say, plausible. There is a coolingmist video that shows pump shut off with a mechanical pressure gage installed between the check valve and nozzle. Pressure drops from 180 psi to a few psi in, I don't know, 3 or 4 tenths of a second. The drop rate is very non-linear. It drops the first 100 psi or so in the blink of an eye, then the rest of the way down is what takes most of the time.
In some ways the video is a little lame. For instance they don't show what is coming out of the nozzle! You AEM guys should do a better one! Anyway, thanks for the log.
The AEM log in post #188 is, I would say, plausible. There is a coolingmist video that shows pump shut off with a mechanical pressure gage installed between the check valve and nozzle. Pressure drops from 180 psi to a few psi in, I don't know, 3 or 4 tenths of a second. The drop rate is very non-linear. It drops the first 100 psi or so in the blink of an eye, then the rest of the way down is what takes most of the time.
In some ways the video is a little lame. For instance they don't show what is coming out of the nozzle! You AEM guys should do a better one! Anyway, thanks for the log.
The internal logger in the Injection Monitor Logs 11 different channels, 20 times a second whenever the WMI system is running. These are:
Flow (cc/min): The current measured WMI flow rate from the inline flow sensor
Lower Flow Limit (cc/min): Lowest allowable flow value before triggering alarm delay counter. Based on Injection Percentage
Upper Flow Limit (cc/min): Highest allowable flow value before triggering alarm delay counter. Based on Injection Percentage
Alarm Source: Indicates what triggered the current alarm condition; 0 = no current alarm 1 = low flow condition, 2 = high flow condition, 3 = auxiliary input, 4 = alarm test
Alarm Status: Indicates current state of alarm; 1 = alarm triggered, 0 = alarm not triggered
Alarm Reset Counter (mS): Counts up from zero to Alarm Reset value once flow has returned into the acceptable range. If it reaches the user settable Alarm Reset Value (mS) while keeping flow within the acceptable range the entire time the alarm is reset.
Alarm Delay Counter (mS): Counts up from zero whenever the flow occurs outside the high or low flow limits. If the counter reaches the user settable Alarm Delay Limit then the alarm will trigger. The counter will reset back to zero if flow returns back into the acceptable range once count up has begun
INJ (%): Injection percentage value. Typically the pump drive duty cycle.
Alarm Reset Limit (mS): Alarm Reset value (User settable static value in config software)
Alarm Delay Limit (mS): Alarm Delay value (User settable static value in config software)
Calibration Changed: Flag to indicate that a configuration setting has changed
You can use these values to fine tune the system to catch all flow rates that are out of bounds and to set yuor criteria as tight as possible yet still suffer no false alarms.
I deleted most of these channels for my post for easier viewing since I was only interested in showing the flow after the pump was abruptly shut off.
Sep 22, 2010, 10:34 AM
#199
A few more comments/questions:
Firstly, why does the pump duty ramp down and not drop directly down to zero? Is this solely due to the time it takes thec boost to drop?
Secondly it is interesting that the water/meth flow rate appears to be relatively proportional to pump duty. This is not what posts I have read elsewhere on this board suggest.
My personal experience with several PPS systems is that if you tune it in third gear it will end up very lean in 1st gear, lean in 2nd gear and rich in 4th gear. I attributed this to the time it takes the pump to speed up and the water/meth in the line to pressurize. Are there other factors at play?
It would be interesting to see a boost log along with pump duty and flow for 1st, 2nd, 3rd and fourth gear pulls.
Firstly, why does the pump duty ramp down and not drop directly down to zero? Is this solely due to the time it takes thec boost to drop?
Secondly it is interesting that the water/meth flow rate appears to be relatively proportional to pump duty. This is not what posts I have read elsewhere on this board suggest.
My personal experience with several PPS systems is that if you tune it in third gear it will end up very lean in 1st gear, lean in 2nd gear and rich in 4th gear. I attributed this to the time it takes the pump to speed up and the water/meth in the line to pressurize. Are there other factors at play?
It would be interesting to see a boost log along with pump duty and flow for 1st, 2nd, 3rd and fourth gear pulls.
Sep 22, 2010, 10:50 AM
#200
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A few more comments/questions:
Firstly, why does the pump duty ramp down and not drop directly down to zero? Is this solely due to the time it takes thec boost to drop?
Secondly it is interesting that the water/meth flow rate appears to be relatively proportional to pump duty. This is not what posts I have read elsewhere on this board suggest.
My personal experience with several PPS systems is that if you tune it in third gear it will end up very lean in 1st gear, lean in 2nd gear and rich in 4th gear. I attributed this to the time it takes the pump to speed up and the water/meth in the line to pressurize. Are there other factors at play?
It would be interesting to see a boost log along with pump duty and flow for 1st, 2nd, 3rd and fourth gear pulls.
Firstly, why does the pump duty ramp down and not drop directly down to zero? Is this solely due to the time it takes thec boost to drop?
Secondly it is interesting that the water/meth flow rate appears to be relatively proportional to pump duty. This is not what posts I have read elsewhere on this board suggest.
My personal experience with several PPS systems is that if you tune it in third gear it will end up very lean in 1st gear, lean in 2nd gear and rich in 4th gear. I attributed this to the time it takes the pump to speed up and the water/meth in the line to pressurize. Are there other factors at play?
It would be interesting to see a boost log along with pump duty and flow for 1st, 2nd, 3rd and fourth gear pulls.
The flow does follow pump duty and is far more repeatable than some people here would have you believe, which is why I want people to post real data, not fantasy pictures that support you giving them your money. It is not linear, nor does it follow duty perfectly but it is much better and far more usable than some suggest.
Here is a screen shot that contains an X-Y plot of a bunch of different runs logged with the new Injection Monitor. The X-Axis is pump duty cycle and the Y axis is measured flow. This is the home screen (for lack of a better description) of the InjMon software we supply with the unit and every time you connect, it populates this X-Y plot with the actual internally logged data logged from your most recent runs.
You can see it is not linear but it is predictable. You can even see the run on data points on the top left. Each run on event left 1 or 2 points as the throttle was abruptly shut off and the flow took a short time (.1 sec or so) before it started to respond. (keep in mind that on our controller minimum pump duty is 15% and full on is ~90%)
Sep 22, 2010, 10:23 PM
#201
Evolving Member
The flow does follow pump duty and is far more repeatable than some people here would have you believe, which is why I want people to post real data, not fantasy pictures that support you giving them your money. It is not linear, nor does it follow duty perfectly but it is much better and far more usable than some suggest.
Here is a screen shot that contains an X-Y plot of a bunch of different runs logged with the new Injection Monitor. The X-Axis is pump duty cycle and the Y axis is measured flow.
Here is a screen shot that contains an X-Y plot of a bunch of different runs logged with the new Injection Monitor. The X-Axis is pump duty cycle and the Y axis is measured flow.
Your logger looks like a good thing, very nice.
Sep 22, 2010, 11:10 PM
#202
Evolving Member
The wall wetting - makes sense to me that if the nozzle is located near the bottom of a more or less horizontal pipe, aimed upward, it will wet mostly the top wall of the pipe. If there is a lot of wetting, at least it will want to fall down, back into the air stream instead of just laying there. Also I'm not so sure that having the nozzle centerline perp to the pipe centerline is the greatest, since that opposite wall will only be about 2.5 inches away! Maybe the nozzle should shoot at an angle, downstream. These are just ideas, don't have data.
Depressurizing the line - since water is incompressible, the line itself should depressurize in an instant, except for whatever expansion the hose may have undergone while pressurized (accumulator effect). If the hose is made of nylon 11 (or nylon 12) and if it is fairly thick wall and small ID, there should be almost no accumulator effect due to ballooning of the hose. Let's say a .250 OD, .050 wall, .150 ID nylon 11 hose. This stuff is pretty stout, I don't think it is going to move very far at 200 psi.
BTW, shopping for nylon hose, I noticed that the thicker the wall, the smaller the minimum allowable bend radius (for a given OD). Didn't expect this but it makes sense I guess. The thicker wall would make it harder for the hose to go out of round (flatten) when you bend it.
Last edited by Talonboost; Sep 22, 2010 at 11:12 PM.
Sep 23, 2010, 01:06 AM
#204
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The myth of "dribble or no dribble" is at last being discussed in some depth.
Video captures, theoretical prediction supported by realtime data log and observations at 09 SEMA. Counter claims of "negligible dribble" or "no run-on" has been presented by NS@AEM and JR@AEM, maker and designer of the PPS system.
So far, we have not been shown a visual presentation of the spraying jet from AEM (preferably specifying the tubing material and length used).
The speed of "bleed-down" is inversely proportional to the size of jet. It just means the same amount of fluid will be dumped at different rates. The amount dumped is directly proportinal to the length of the tubing and the initial/final pressure change.
True or false? It will be up to the readers to decide.
Video captures, theoretical prediction supported by realtime data log and observations at 09 SEMA. Counter claims of "negligible dribble" or "no run-on" has been presented by NS@AEM and JR@AEM, maker and designer of the PPS system.
So far, we have not been shown a visual presentation of the spraying jet from AEM (preferably specifying the tubing material and length used).
The speed of "bleed-down" is inversely proportional to the size of jet. It just means the same amount of fluid will be dumped at different rates. The amount dumped is directly proportinal to the length of the tubing and the initial/final pressure change.
True or false? It will be up to the readers to decide.
Last edited by Richard L; Sep 23, 2010 at 11:59 AM. Reason: typo
Sep 23, 2010, 08:32 AM
#205
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The myth of "dribble or no dribble" is at last being discussed in some depth.
Video captures, theoretical prediction supported by realtime data log and observations at 09 SEMA. Counter claims of "neglectable dribble or "no run-on" has been presented by NS@AEM and JR@AEM, maker and designer of the PPS system.
So far, we have not been shown a visual presentation of the spraying jet from AEM (preferably specifying the tubing material and length used).
The speed of "bleed-down" is inversely proportional to the size of jet. It just means the same amount of fluid will be dumped at different rates. The amount dumped is directly proportinal to the length of the tubing and the initial/final pressure change.
True or false? It will be up to the readers to decide.
Video captures, theoretical prediction supported by realtime data log and observations at 09 SEMA. Counter claims of "neglectable dribble or "no run-on" has been presented by NS@AEM and JR@AEM, maker and designer of the PPS system.
So far, we have not been shown a visual presentation of the spraying jet from AEM (preferably specifying the tubing material and length used).
The speed of "bleed-down" is inversely proportional to the size of jet. It just means the same amount of fluid will be dumped at different rates. The amount dumped is directly proportinal to the length of the tubing and the initial/final pressure change.
True or false? It will be up to the readers to decide.
Richard, you have been ducking this for the last few days and I think it's time you back up your earlier posts regarding the bleed down. Your admittedly fabricated graphs showing extreme bleed down have been soundly refuted by actual recorded data. 3 days ago you asked for information that will "help me to create a better simulated PPS line (yellow) on the chart." I went above and beyond your request and provided actual flow versus pump duty and flow versus time data plots. Yet rather than update (fix) your wildly incorrect earlier posts on this subject you respond with requests for us to now provide more data, videos etc.
Sorry Richard, I think everyone here will agree I have made very few claims but backed up those I have made with very strong, legitimate data.
Richard, You have made many claims and only backed them up with admittedly fabricated data representing your "assumptions".
So I ask again Richard, please show us your data. It's overdue.
Sep 23, 2010, 08:41 AM
#206
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I would say this flow vs pump duty cycle curve looks similar to a flow vs pressure curve for a nozzle. In other words, it looks like the pressure would vary more or less linearly with pump duty cycle. Which is ok I think, as long as the user knows this is what is happening, and not expecting flow to be linear with duty cycle. Well wait a minute, can the user make his own 2D injection map, you know, like maybe 8 by 8 cells, with whatever he wants for values in each cell?
Your logger looks like a good thing, very nice.
Your logger looks like a good thing, very nice.
The logger in the new AEM Boost Safe is almost worth the price of the unit by itself. Up till now everybody keeps making assertions based on what they believe or assume is happening, now it's time to take a much needed step forward and work with whats really happening.
Sep 23, 2010, 08:50 AM
#207
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These are things I was thinking about when I asked earlier about nozzle orientation and made a comment about the rigidity of nylon hose. But I got no nibbles on it.
The wall wetting - makes sense to me that if the nozzle is located near the bottom of a more or less horizontal pipe, aimed upward, it will wet mostly the top wall of the pipe. If there is a lot of wetting, at least it will want to fall down, back into the air stream instead of just laying there. Also I'm not so sure that having the nozzle centerline perp to the pipe centerline is the greatest, since that opposite wall will only be about 2.5 inches away! Maybe the nozzle should shoot at an angle, downstream. These are just ideas, don't have data.
Depressurizing the line - since water is incompressible, the line itself should depressurize in an instant, except for whatever expansion the hose may have undergone while pressurized (accumulator effect). If the hose is made of nylon 11 (or nylon 12) and if it is fairly thick wall and small ID, there should be almost no accumulator effect due to ballooning of the hose. Let's say a .250 OD, .050 wall, .150 ID nylon 11 hose. This stuff is pretty stout, I don't think it is going to move very far at 200 psi.
The wall wetting - makes sense to me that if the nozzle is located near the bottom of a more or less horizontal pipe, aimed upward, it will wet mostly the top wall of the pipe. If there is a lot of wetting, at least it will want to fall down, back into the air stream instead of just laying there. Also I'm not so sure that having the nozzle centerline perp to the pipe centerline is the greatest, since that opposite wall will only be about 2.5 inches away! Maybe the nozzle should shoot at an angle, downstream. These are just ideas, don't have data.
Depressurizing the line - since water is incompressible, the line itself should depressurize in an instant, except for whatever expansion the hose may have undergone while pressurized (accumulator effect). If the hose is made of nylon 11 (or nylon 12) and if it is fairly thick wall and small ID, there should be almost no accumulator effect due to ballooning of the hose. Let's say a .250 OD, .050 wall, .150 ID nylon 11 hose. This stuff is pretty stout, I don't think it is going to move very far at 200 psi.
Water is an incompressible fluid. If you have it in a rigid hose the pressure increase and decrease is near instantaneous. Only when there is air in the system will there be any significant flow after the pump stops, the air will want to take up more space in the line when the pressure drops. When the lines are free of air and the pump stops the pressure drops fast. The fluid makes no attempt to expand because it wasn't compressed in the first place, because it is an incompressible fluid.
I guess someone building a DIY kit and buying generic hose out of some catalog could overlook this very important step and create a system with significant run on, especially with a long feed hose, that's why videos made years ago that nobody knows anything about are so useless in an intelligent discussion.
Last edited by JR From AEM; Sep 23, 2010 at 09:18 AM. Reason: grammer
Sep 23, 2010, 08:51 AM
#208
Help me understand...
From looking at the log it appears that the system contiuned to flow near 500cc for about .1 seconds before rapidly falling to 0cc in the last .05 after the pump had shut off. The other thing I noticed is the ramp up of the system after turning back on. It seems to jump up and almost platuea before jumping up again. Is this due to the pump building pressure in the system? Was a check valve in place on the system?
I would like to say thanks to both Aquamist and AEM for putting so much info out on this subject for the community and keeping it relativly civil and on track. I think this may be a first.
From looking at the log it appears that the system contiuned to flow near 500cc for about .1 seconds before rapidly falling to 0cc in the last .05 after the pump had shut off. The other thing I noticed is the ramp up of the system after turning back on. It seems to jump up and almost platuea before jumping up again. Is this due to the pump building pressure in the system? Was a check valve in place on the system?
I would like to say thanks to both Aquamist and AEM for putting so much info out on this subject for the community and keeping it relativly civil and on track. I think this may be a first.
Sep 23, 2010, 08:52 AM
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These are things I was thinking about when I asked earlier about nozzle orientation and made a comment about the rigidity of nylon hose. But I got no nibbles on it.
The wall wetting - makes sense to me that if the nozzle is located near the bottom of a more or less horizontal pipe, aimed upward, it will wet mostly the top wall of the pipe. If there is a lot of wetting, at least it will want to fall down, back into the air stream instead of just laying there. Also I'm not so sure that having the nozzle centerline perp to the pipe centerline is the greatest, since that opposite wall will only be about 2.5 inches away! Maybe the nozzle should shoot at an angle, downstream. These are just ideas, don't have data.
Depressurizing the line - since water is incompressible, the line itself should depressurize in an instant, except for whatever expansion the hose may have undergone while pressurized (accumulator effect). If the hose is made of nylon 11 (or nylon 12) and if it is fairly thick wall and small ID, there should be almost no accumulator effect due to ballooning of the hose. Let's say a .250 OD, .050 wall, .150 ID nylon 11 hose. This stuff is pretty stout, I don't think it is going to move very far at 200 psi.
The wall wetting - makes sense to me that if the nozzle is located near the bottom of a more or less horizontal pipe, aimed upward, it will wet mostly the top wall of the pipe. If there is a lot of wetting, at least it will want to fall down, back into the air stream instead of just laying there. Also I'm not so sure that having the nozzle centerline perp to the pipe centerline is the greatest, since that opposite wall will only be about 2.5 inches away! Maybe the nozzle should shoot at an angle, downstream. These are just ideas, don't have data.
Depressurizing the line - since water is incompressible, the line itself should depressurize in an instant, except for whatever expansion the hose may have undergone while pressurized (accumulator effect). If the hose is made of nylon 11 (or nylon 12) and if it is fairly thick wall and small ID, there should be almost no accumulator effect due to ballooning of the hose. Let's say a .250 OD, .050 wall, .150 ID nylon 11 hose. This stuff is pretty stout, I don't think it is going to move very far at 200 psi.
Water is an incompressible fluid. If you have it it a rigid hose the pressure increase and decrease is near instantaneous. Only when there is air in the system will there be any significant flow after the pump stops, the air will want to take up more space in the line when the pressure drops. When the lines are free of air and the pump stops the pressure drops fast. The fluid makes no attempt to expand because it wasn't compressed in the first place, because it is an incompressible fluid.
I guess someone building a DIY kit and buying generic hose out of some catalog could overlook this very important step and create a system with significant run on, especially with a long feed hose, that's why videos made years ago that nobody knows anything about are so useless in an intelligent discussion.
Sep 23, 2010, 09:13 AM
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Help me understand...
From looking at the log it appears that the system contiuned to flow near 500cc for about .1 seconds before rapidly falling to 0cc in the last .05 after the pump had shut off. The other thing I noticed is the ramp up of the system after turning back on. It seems to jump up and almost platuea before jumping up again. Is this due to the pump building pressure in the system? Was a check valve in place on the system?
I would like to say thanks to both Aquamist and AEM for putting so much info out on this subject for the community and keeping it relativly civil and on track. I think this may be a first.
From looking at the log it appears that the system contiuned to flow near 500cc for about .1 seconds before rapidly falling to 0cc in the last .05 after the pump had shut off. The other thing I noticed is the ramp up of the system after turning back on. It seems to jump up and almost platuea before jumping up again. Is this due to the pump building pressure in the system? Was a check valve in place on the system?
I would like to say thanks to both Aquamist and AEM for putting so much info out on this subject for the community and keeping it relativly civil and on track. I think this may be a first.
Yes, the .1 second is essentially the stop time of the pump after being turned off. It take a serious amount of juice (up to 10 amps!) to keep these pumps spinning against a 200 PSI line pressure and once that power is removed the pump stops very quickly. It doesn't keep spinning like a freewheeling skateboard wheel! Once the pump stops turning and with the incompressibility of water being what it is (see above posts) the presssure drops very, very fast and since the only thing forcing the fluid out the jet is the pressure differential, which has vanished, the flow stops. I suspect that if we logged at faster than our current rate (every 0.050 second) you would see a more rounded decrease in flow but the log sample rate makes it look like steps.
As to the flow increase once the pump power is returned you are seeing some of the non linearity of the system, which is most pronounced at low pump speeds. The flow increases at a greater rate in the lower duty cycles then increases less rapidly off as max pressure is approached (see x-y plot of actual data below, flow rate versus pump duty cycle).
As to a check valve, yes, one was installed as our injection nozzles themselves now have the check valve integrated into them. We are continually striving to improve our system. These new injectors are easily identified as they are now black and they have a removable fitting on the end so different fittings can now be installed if the end user wants something other than the straight one supplied.
