Axial Flow Supercharger
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Joined: Feb 2005
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Toasty, Think a little bit further. If the compressor is running in between the engine and throtle body, it is running in partial vacuume when not needed. It regulates itself by giving dense or not soo dense air. If it is thin then nothing is being compressed and no power is being used. This compressor will run without the belt on. It will just spin happily along and not stop spinning unti the engine has been off for 15-20 seconds. Once upon a time GM asked me to calculate the HP drain during freeway cruise. They gave me numbers like how many grams a second and so on. I ran the numbers and called the engineer back I told him that the best I could come up with is 1 HP. That was giving every possable credit to the down side. There were just to many zero's in the equations. He said that is exactly what he did and had the same answer. So Mad Max be damned. Besides that a clutch that will hold a big dragrace blower would have too be bigger than the clutch in your S2000. No kidding. The current ones use 1000 hp to turn.
Joined: Aug 2002
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From: Mount Rainier
Rich,
Are you saying, that in this application, the compressor would be located between the throttle body and the intake manifold?
If so, then could the throttle body be angled to one side, if more room is need?
BTW, I'm a young, retired Navy gas turbine operator. GE LM2500s, Alison 501K17s, Avco TF40Bs. Running a GE Frame 7 now.
The High Speed Internal Combustion Engine for beteen $224 to $600
Keep it comming.
Are you saying, that in this application, the compressor would be located between the throttle body and the intake manifold?
If so, then could the throttle body be angled to one side, if more room is need?
BTW, I'm a young, retired Navy gas turbine operator. GE LM2500s, Alison 501K17s, Avco TF40Bs. Running a GE Frame 7 now.
The High Speed Internal Combustion Engine for beteen $224 to $600
Keep it comming.
Thread Starter
Joined: Feb 2005
Posts: 239
Likes: 3
Yes, they really need to publish a new batch of that work to bring the price down.
I lost mine at one time and was lucky to inherit Dave Zeuschels.
A nice piece of personal property from my good friend and world class engine builder. Builder of record breaking P-51 Mustangs/Merlins.
As it currently is the inlet is on the rear of the SC for axial intake. As I hinted at before the low pressure porting is more important so if you have to make a turn better to do it on the pressure side. I have the freedom to change the direction of flow at the design stage. I have built them both ways. If I have to bring it in the front then it will be a lot better to give it an angle. This makes the unit longer though. As it is now the unit is designed for the most compact packaging.
Right now it is almost like a banjo fitting except that it has a ramp in the annular area. To do a redesign it will take a lot of new parts as the planetary set is nested inside the groove. There is no room unless the main shaft is extended and the cavity moved infront of the annular groove.
These are design compromises that unfortunately must be worked through. It would be nice to have it go right through like a jet engine with no turns. We have engine compartments not wings to mount in/on.
I did not answer the electronic controls question. The problem is twofold. I want to get CARB certs for this and we would have to have control that is approved and password protected from tampering. Personally I would like to be able to tune my own engine if I were the buyer. On the other hand someone is going to melt one down if he goes to far. In that case it will always get blamed on the SC itself. This gives me a bad name.
When I built the big V8 units and worked out the best combinations on our inhouse engine dyno someone always knew better and had failures. I had the failures on the dyno so they didn't have to bit they still went there. This isn't good for anyone except the piston manufactures. I think they already have enough sales to the top fuel guys.
That doesn't answer your question. I can make exceptions as I don't sell that many blowers that they go through the distributor/dealer system. I have direct contact with buyers and can make exceptions if I like. It is not in my favor to see a user having to spend more money. It is counter productive. At the moment I'm leaning towards the E manage unit. As I understand it I could take a users existing unit and load our maps in it. Then lock it so we both get what we want. If someone has a unit that differs from whatever we use then I can't help him.
I intend to be selling a unit that someone buys and drives. Not something that you keep screwing with to get the last 3HP. There will be someone who gets me to add a stage or two for them and go crazy but that is not the target. In fact we may have to do somthing like that ourselves as a sales tool. I'd prefer to just have a normal street driver as a demo. Yet we all know that magazines have to have huge bottom line tests to sell things.
I lost mine at one time and was lucky to inherit Dave Zeuschels.
A nice piece of personal property from my good friend and world class engine builder. Builder of record breaking P-51 Mustangs/Merlins.
As it currently is the inlet is on the rear of the SC for axial intake. As I hinted at before the low pressure porting is more important so if you have to make a turn better to do it on the pressure side. I have the freedom to change the direction of flow at the design stage. I have built them both ways. If I have to bring it in the front then it will be a lot better to give it an angle. This makes the unit longer though. As it is now the unit is designed for the most compact packaging.
Right now it is almost like a banjo fitting except that it has a ramp in the annular area. To do a redesign it will take a lot of new parts as the planetary set is nested inside the groove. There is no room unless the main shaft is extended and the cavity moved infront of the annular groove.
These are design compromises that unfortunately must be worked through. It would be nice to have it go right through like a jet engine with no turns. We have engine compartments not wings to mount in/on.
I did not answer the electronic controls question. The problem is twofold. I want to get CARB certs for this and we would have to have control that is approved and password protected from tampering. Personally I would like to be able to tune my own engine if I were the buyer. On the other hand someone is going to melt one down if he goes to far. In that case it will always get blamed on the SC itself. This gives me a bad name.
When I built the big V8 units and worked out the best combinations on our inhouse engine dyno someone always knew better and had failures. I had the failures on the dyno so they didn't have to bit they still went there. This isn't good for anyone except the piston manufactures. I think they already have enough sales to the top fuel guys.
That doesn't answer your question. I can make exceptions as I don't sell that many blowers that they go through the distributor/dealer system. I have direct contact with buyers and can make exceptions if I like. It is not in my favor to see a user having to spend more money. It is counter productive. At the moment I'm leaning towards the E manage unit. As I understand it I could take a users existing unit and load our maps in it. Then lock it so we both get what we want. If someone has a unit that differs from whatever we use then I can't help him.
I intend to be selling a unit that someone buys and drives. Not something that you keep screwing with to get the last 3HP. There will be someone who gets me to add a stage or two for them and go crazy but that is not the target. In fact we may have to do somthing like that ourselves as a sales tool. I'd prefer to just have a normal street driver as a demo. Yet we all know that magazines have to have huge bottom line tests to sell things.
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Joined: Jan 2005
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From: Greenville, SC
Originally Posted by Richard Paul' date='Feb 16 2005, 08:41 PM
Toasty, Think a little bit further. If the compressor is running in between the engine and throtle body, it is running in partial vacuume when not needed. It regulates itself by giving dense or not soo dense air. If it is thin then nothing is being compressed and no power is being used. This compressor will run without the belt on. It will just spin happily along and not stop spinning unti the engine has been off for 15-20 seconds. Once upon a time GM asked me to calculate the HP drain during freeway cruise. They gave me numbers like how many grams a second and so on. I ran the numbers and called the engineer back I told him that the best I could come up with is 1 HP. That was giving every possable credit to the down side. There were just to many zero's in the equations. He said that is exactly what he did and had the same answer. So Mad Max be damned. Besides that a clutch that will hold a big dragrace blower would have too be bigger than the clutch in your S2000. No kidding. The current ones use 1000 hp to turn.
I still would like to know what the static flow-thru resistance would be compared to the other types of superchargers. I am guessing yours would be better (also considering the lack of extra tubing and resistance of an intercooler).
OK my next idea is this. If your compressor is indeed more efficent as it seems then you might entertain the idea of a turbo kit utilizing your axial flow compressor replacing the standard compressor-half of the turbo.
I imagine Garrett would be beating your door down to get their diesel turbos more efficent...No?
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Joined: Feb 2005
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No, if you turned it off you would gain nothing but complications.
Static flow through? You mean compared to say a roots or a screw? Those two would shut the airflow off. A centrifugal, I'mnot sure, it depends on the scroll design. If this were shut down and locked in place? Air would still go through but the more you ask for the more resistance there will be. If you just released the drive and let it spin there would be less resistance.
Why would Garrett beat a path to my door? How much does it cost to make a little compressor wheel and a housing? Now how much does it cost to make my compressor? That's litterally two parts they are making, both castings. They couldn't make one stage of an axial flow compressor for that. Add all the other parts and the tolarences they'd have to hold. I'm not waiting for them.
Static flow through? You mean compared to say a roots or a screw? Those two would shut the airflow off. A centrifugal, I'mnot sure, it depends on the scroll design. If this were shut down and locked in place? Air would still go through but the more you ask for the more resistance there will be. If you just released the drive and let it spin there would be less resistance.
Why would Garrett beat a path to my door? How much does it cost to make a little compressor wheel and a housing? Now how much does it cost to make my compressor? That's litterally two parts they are making, both castings. They couldn't make one stage of an axial flow compressor for that. Add all the other parts and the tolarences they'd have to hold. I'm not waiting for them.
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From: Huntsville AL
Is it not necessary to vent (blow off) the compressed mass inside the manifold/plenum when shifting at high rpm?
How long will it take for the air charge in the manifold to drop back to ambient or vacuum when shifting at 8000 rpm (2004 S2k) if not venting?
Would the engine not continue to rev when unloaded (clutch disengaged) until the air charge inside the manifold reaches a vacuum state.
Would the compressor act as an engine break during this time?
energy input to the outlet side of the compressor due to the high pressure and the vacuum on the inlet side making the compressor slow down applying energy to the engine to reduce the rpms?
If you do not vent this pressure could this create some possible cavitation issues with the outlet side of the compressor being at a higher pressure than the intake side? Back Flow?
Yes the pulley/belt is still turning the compressor so the compressor would not stop because of back flow. More energy is being applied to the compressor from the pulley/ engine than the energy that could be applied from back flow through the compressor.
How long will it take for the air charge in the manifold to drop back to ambient or vacuum when shifting at 8000 rpm (2004 S2k) if not venting?
Would the engine not continue to rev when unloaded (clutch disengaged) until the air charge inside the manifold reaches a vacuum state.
Would the compressor act as an engine break during this time?
energy input to the outlet side of the compressor due to the high pressure and the vacuum on the inlet side making the compressor slow down applying energy to the engine to reduce the rpms?
If you do not vent this pressure could this create some possible cavitation issues with the outlet side of the compressor being at a higher pressure than the intake side? Back Flow?
Yes the pulley/belt is still turning the compressor so the compressor would not stop because of back flow. More energy is being applied to the compressor from the pulley/ engine than the energy that could be applied from back flow through the compressor.
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Joined: Feb 2005
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I'm not a good teacher, but this is not to hard if you will just forget all that turbo stuff. Almost every question you have can be answered if you just realize that there is nothing in there when the throtle is closed. The other thing you must realize is that manifold pressure is only the resistance.
Everything that the blower puts out has to get in. If you think of this as MASS not pressure or volume. The same volume is always going into the engine. By that I mean if you have a 2 liter engine it will pump 2 liters every two revolutions.
Forget the term "volumetric efficency" it is missleading. The same volume goes in no matter how efficent the engiine is or isn't.
This manifold will give you 95% volumetric efficency. Bla BLA, heard it haven't you. That is wrong, the volume is not going to change. You mesure it with tools, hard tools. You figure it out mathmaticly. It can't be a 1.5 liter motor sometime and some time another dispacment. It can't change size.
The volume you are talking about is that contained in the engine. Do you have more or kless volume in yur engine because you modified it? Changing bore and stroke will change this, wise guy. I pre emptied that crack. But all you might have done thinking you change the volume isn't happining.
Having said all that, what does happen then? The mass efficency changes. So if the throtle is almost closed less mass is displacing the same volume right?
So the supercharger passes the same volume but more mass. Yet it can't pass any more then you need as you will close the throtle if your going to fast right? then there is less mass and you slow down.
When there is less mass in the supercharger it can't compress it, can it?
So it does no work, there is no energy being used or put into the charge.
All this happens so instantly that it cannotbe detected. There is no lag in either direction, on or off the throtle. Changing the rotor sopeed has no effect only the mass you let in by adjusting the gas pedal.
As to venting. Do you want to vent air that has fuel in it? We are after the throtle body. Even though the fuel is injected later do you want to take a chance when the new low pressure area is behind the squirt. It will come back. Think about it for a minuit this is what you aretryingtoprevent. If you vent the air tho atmospheric then you have to use the power to drive the blower. just close the throtle and it adjusts itself. I didn't invent this mother nature did it.
Figure the air at peak is traveling at 400 feet per second. How long does it take to get int the manifold. You can answer you own question with a calculator.
I hope I got it all. If I missed something I'm sure you guys will let me know.
For now I'm out, Richard
Everything that the blower puts out has to get in. If you think of this as MASS not pressure or volume. The same volume is always going into the engine. By that I mean if you have a 2 liter engine it will pump 2 liters every two revolutions.
Forget the term "volumetric efficency" it is missleading. The same volume goes in no matter how efficent the engiine is or isn't.
This manifold will give you 95% volumetric efficency. Bla BLA, heard it haven't you. That is wrong, the volume is not going to change. You mesure it with tools, hard tools. You figure it out mathmaticly. It can't be a 1.5 liter motor sometime and some time another dispacment. It can't change size.
The volume you are talking about is that contained in the engine. Do you have more or kless volume in yur engine because you modified it? Changing bore and stroke will change this, wise guy. I pre emptied that crack. But all you might have done thinking you change the volume isn't happining.
Having said all that, what does happen then? The mass efficency changes. So if the throtle is almost closed less mass is displacing the same volume right?
So the supercharger passes the same volume but more mass. Yet it can't pass any more then you need as you will close the throtle if your going to fast right? then there is less mass and you slow down.
When there is less mass in the supercharger it can't compress it, can it?
So it does no work, there is no energy being used or put into the charge.
All this happens so instantly that it cannotbe detected. There is no lag in either direction, on or off the throtle. Changing the rotor sopeed has no effect only the mass you let in by adjusting the gas pedal.
As to venting. Do you want to vent air that has fuel in it? We are after the throtle body. Even though the fuel is injected later do you want to take a chance when the new low pressure area is behind the squirt. It will come back. Think about it for a minuit this is what you aretryingtoprevent. If you vent the air tho atmospheric then you have to use the power to drive the blower. just close the throtle and it adjusts itself. I didn't invent this mother nature did it.
Figure the air at peak is traveling at 400 feet per second. How long does it take to get int the manifold. You can answer you own question with a calculator.
I hope I got it all. If I missed something I'm sure you guys will let me know.
For now I'm out, Richard
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Joined: Jan 2005
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From: Greenville, SC
Originally Posted by Richard Paul' date='Feb 21 2005, 02:38 PM
No, if you turned it off you would gain nothing but complications.
Static flow through? You mean compared to say a roots or a screw? Those two would shut the airflow off. A centrifugal, I'mnot sure, it depends on the scroll design. If this were shut down and locked in place? Air would still go through but the more you ask for the more resistance there will be. If you just released the drive and let it spin there would be less resistance.
Why would Garrett beat a path to my door? How much does it cost to make a little compressor wheel and a housing? Now how much does it cost to make my compressor? That's litterally two parts they are making, both castings. They couldn't make one stage of an axial flow compressor for that. Add all the other parts and the tolarences they'd have to hold. I'm not waiting for them.
Static flow through? You mean compared to say a roots or a screw? Those two would shut the airflow off. A centrifugal, I'mnot sure, it depends on the scroll design. If this were shut down and locked in place? Air would still go through but the more you ask for the more resistance there will be. If you just released the drive and let it spin there would be less resistance.
Why would Garrett beat a path to my door? How much does it cost to make a little compressor wheel and a housing? Now how much does it cost to make my compressor? That's litterally two parts they are making, both castings. They couldn't make one stage of an axial flow compressor for that. Add all the other parts and the tolarences they'd have to hold. I'm not waiting for them.
The Garrett comment was merely a compliment which you didn't seem to get. And I suppose if refined, your machine could be composed of castings as well??? Cheap is relative, mass quantity reduces cost, yada yada.
I still ask...have you considered a turbo design utilizing your compressor...just imagined...it doesnt have to come to fruition. It would seem to have an appeal...better efficency/less heat, even though the cost would be higher.
