Devilsown Methanol Alcohol Water Injection - View Single Post

Rocket468 · 04-26-2007

There is benefit and draw back to accumulators when used in an water injection system. diaphragm pumps natural will pulse as the motor runs. Accumulators will smooth out these.

Also if you are using a solenoid it will help extend the life of it as when the solenoid closes it will cause a spike between the solenoid and pump. This is one of the reasons solenoids wear out so quick in a water injection system. The pressure spike(acoustic wave)created at rapid solenoid closure can be high as two(2) times the system working pressure. Unrestricted, this pressure spike or wave will rapidly accelerate to the speed of sound in liquid, which can exceed 4000 ft/sec.

P = (0.070) (V) (L) / t + P1

Where P = Increase in pressure
P1 = Inlet Pressure
V = Flow velocity in ft/sec 5.0 ft / sec for PP
t = Time in sec.(Valve closing time)
L = Upstream Tube Length in feet

Check valves don't have an abrupt off so they don't allow the system pressure to spike. But they do suffer from the bleed(below)

Now the problem with em. The larger the volume the more bleed time they will have when the system turns off the alcohol water mixture is going to run out thur the nozzle. Also since they do add volume to the system they will make progressive system react slow.

That accumulator was designed by shurflo for a completely different use. Its way to much volume. So this is where bigger is not always better. We have our own that we hope to have out soon. Its going to be aprox 25cc in volume. Which i recommend not going much bigger if you choose to run one.

04-26-2007	#2 (permalink)
Rocket468 DevilsOwn Staff Join Date: Apr 2005 Posts: 1,150	Re: Accumulator, is it needed ? There is benefit and draw back to accumulators when used in an water injection system. diaphragm pumps natural will pulse as the motor runs. Accumulators will smooth out these. Also if you are using a solenoid it will help extend the life of it as when the solenoid closes it will cause a spike between the solenoid and pump. This is one of the reasons solenoids wear out so quick in a water injection system. The pressure spike(acoustic wave)created at rapid solenoid closure can be high as two(2) times the system working pressure. Unrestricted, this pressure spike or wave will rapidly accelerate to the speed of sound in liquid, which can exceed 4000 ft/sec. P = (0.070) (V) (L) / t + P1 Where P = Increase in pressure P1 = Inlet Pressure V = Flow velocity in ft/sec 5.0 ft / sec for PP t = Time in sec.(Valve closing time) L = Upstream Tube Length in feet Check valves don't have an abrupt off so they don't allow the system pressure to spike. But they do suffer from the bleed(below) Now the problem with em. The larger the volume the more bleed time they will have when the system turns off the alcohol water mixture is going to run out thur the nozzle. Also since they do add volume to the system they will make progressive system react slow. That accumulator was designed by shurflo for a completely different use. Its way to much volume. So this is where bigger is not always better. We have our own that we hope to have out soon. Its going to be aprox 25cc in volume. Which i recommend not going much bigger if you choose to run one.