Wind Tunnel Dyno Pictures
#1
Former Vendor of MBWorld
Thread Starter
Wind Tunnel Dyno Pictures
Here are some photos of our wind tunnel dyno that we have at our shop in Torrance, California. If you are in SoCal and you need any performance part installations done, tuning, fabrication, testing or just want to come by one day to check out our facility, everyone is welcome.
Our priority at our shop is customer service and delivering beyond expectations. We have invested in our facility so that we can meet our customers needs.
We have a service center, fabrication facility, capabilities to weld any material and we are constantly upgrading our tuning capabilities as well.
I hope that you enjoy the photos of our dyno.
Please feel free to get in touch with me regarding any of your needs.
Thanks-
-Craig
Our priority at our shop is customer service and delivering beyond expectations. We have invested in our facility so that we can meet our customers needs.
We have a service center, fabrication facility, capabilities to weld any material and we are constantly upgrading our tuning capabilities as well.
I hope that you enjoy the photos of our dyno.
Please feel free to get in touch with me regarding any of your needs.
Thanks-
-Craig
The following users liked this post:
mthis (09-04-2016)
#2
Super Member
OK, I'm interested in this. Why the wind tunnel? Is it to just to make sure you have enough air flow to cool the car? As far as a wind tunnel, it's not blowing very fast through there. As just an estimate, if the cross section of the room is 10 x 8, or 80 ft2, then with 169,000 CFM that would come out to 24 mph. Well, since the car blocks some of the area, then it's blowing faster than that around the car. And as far as the 5 inches of water pressure rise, are you talking about how much the room pressure goes up with the fan running, or are you measuring the total pressure just downstream of the fan? If it's the pressure in the room, then that's a function of how much is leaked out or blown out through the exhaust. I'm guessing it's just the pressure rise across the fan, which is necessary to move that much air. Of course, 5" of water is pretty small, it's only .036 psi or .25% of one atmosphere.
Sorry for the questions, I'm just trying to figure out what this is all about, it's the first I've heard of a wind tunnel dyno. Please fill me in. I really do want to learn something today. I am being sincere not a wise acre, Thanks.
Sorry for the questions, I'm just trying to figure out what this is all about, it's the first I've heard of a wind tunnel dyno. Please fill me in. I really do want to learn something today. I am being sincere not a wise acre, Thanks.
#3
Former Vendor of MBWorld
Thread Starter
You should read up on static pressure for fans, it's very different than what you are assuming it is. The static pressure only has to do with the fan and it's ability to maintain its CFM.
The cross section of the fan is only 6 square feet, you don't use the cross section of the room for the speed measurement. I am a poor teacher so I am not going to explain and teach you all of this stuff but you can look it all up if you want to learn something today.
The cross section of the fan is only 6 square feet, you don't use the cross section of the room for the speed measurement. I am a poor teacher so I am not going to explain and teach you all of this stuff but you can look it all up if you want to learn something today.
#4
Super Member
You should read up on static pressure for fans, it's very different than what you are assuming it is. The static pressure only has to do with the fan and it's ability to maintain its CFM.
The cross section of the fan is only 6 square feet, you don't use the cross section of the room for the speed measurement. I am a poor teacher so I am not going to explain and teach you all of this stuff but you can look it all up if you want to learn something today.
The cross section of the fan is only 6 square feet, you don't use the cross section of the room for the speed measurement. I am a poor teacher so I am not going to explain and teach you all of this stuff but you can look it all up if you want to learn something today.
Actually I'm a retired Mechanical Engineer and used to work with fans as part of my job. So the velocity coming off the fan is greater, that is correct. But you said the fan had an area of 6 square feet. I'm afraid you are wrong. That would be a fan with a diameter of only 2.76 feet. I think you meant to say the fan was 6 foot in diameter giving it an area of 28.3 square feet. So the velocity coming off the fan is 68 mph. But the problem is this airflow will immediately diffuse into the room and the end result will be an airflow over the car of around half of that, maybe 35 mph. Also, I am aware of the pressure rise across an axial fan. The pressure rise is only 5 inches of water or as I stated before that's only .036 psi. Actually, by my calculations, the stagnation pressure at 68 mph is around .08 psi, so I think maybe your 5 inches is a little low or possibly the fan is bigger than 6 foot in diameter (more like 7 feet in diameter). The speed of the air required to give only 5 inches of pressure rise would be 45 mph. But again, it will diffuse quickly and the resulting pressure inside the chamber will basically be ambient.
But here is what is really bothering me, I worked with a wind tunnel during college. Your setup is not a wind tunnel because it blows into the room. A wind tunnel uses a large fan to pull air through a set of straighteners and then over the car. So the air is pulled into the room through a set of straighteners, then it flows over the car, then into the fan and then it exhausts out of the room. Why? Because you don't want all the swirl coming off the fan going over the car. It creates turbulence and does not simulate the air flow over the car it has when it's moving.
So back to my original question, what is the purpose of this setup? It is an excellent setup to make sure the car cools sufficiently, but that's it. I don't see any way it acts as a wind tunnel and even if it did, what does that do for me on a dyno. I looked into it a little more and the NASCAR guys are using wind tunnel dynos, but in their case the car is in an actual wind tunnel (not a make believe wind tunnel) that produces 200 mph and the car is on a moving surface simulating the road moving beneath the car. The fan they use pulls 2,850,000 cubic feet of air through the room. And they dyno their cars with the hoods close so they are looking at ways to improve the flow to the engine to produce more power.
Personally I would never call your setup a wind tunnel dyno, just a very nice dyno with excellent cooling capabilities. I think it's misleading to use the words wind tunnel in your description. So the good news, you actually learned something today. And I also learned something seeing the way NASCAR is using actual wind tunnels during their dyno test. Very cool. And again, I'm sorry if someone tried to convince you that your setup was a wind tunnel. I think it's a very nice setup, it's just not a wind tunnel. Sorry.
Last edited by glennhl; 09-04-2016 at 12:38 PM.
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#5
Super Member
Actually I'm a retired Mechanical Engineer and used to work with fans as part of my job. So the velocity coming off the fan is greater, that is correct. But you said the fan had an area of 6 square feet. I'm afraid you are wrong. That would be a fan with a diameter of only 2.76 feet. I think you meant to say the fan was 6 foot in diameter giving it an area of 28.3 square feet. So the velocity coming off the fan is 68 mph. But the problem is this airflow will immediately diffuse into the room and the end result will be an airflow over the car of around half of that, maybe 35 mph. Also, I am aware of the pressure rise across an axial fan. The pressure rise is only 5 inches of water or as I stated before that's only .036 psi. Actually, by my calculations, the stagnation pressure at 68 mph is around .08 psi, so I think maybe your 5 inches is a little low or possibly the fan is bigger than 6 foot in diameter (more like 7 feet in diameter). The speed of the air required to give only 5 inches of pressure rise would be 45 mph. But again, it will diffuse quickly and the resulting pressure inside the chamber will basically be ambient.
But here is what is really bothering me, I worked with a wind tunnel during college. Your setup is not a wind tunnel because it blows into the room. A wind tunnel uses a large fan to pull air through a set of straighteners and then over the car. So the air is pulled into the room through a set of straighteners, then it flows over the car, then into the fan and then it exhausts out of the room. Why? Because you don't want all the swirl coming off the fan going over the car. It creates turbulence and does not simulate the air flow over the car it has when it's moving.
So back to my original question, what is the purpose of this setup? It is an excellent setup to make sure the car cools sufficiently, but that's it. I don't see any way it acts as a wind tunnel and even if it did, what does that do for me on a dyno. I looked into it a little more and the NASCAR guys are using wind tunnel dynos, but in their case the car is in an actual wind tunnel (not a make believe wind tunnel) that produces 200 mph and the car is on a moving surface simulating the road moving beneath the car. The fan they use pulls 2,850,000 cubic feet of air through the room. And they dyno their cars with the hoods close so they are looking at ways to improve the flow to the engine to produce more power.
Personally I would never call your setup a wind tunnel dyno, just a very nice dyno with excellent cooling capabilities. I think it's misleading to use the words wind tunnel in your description. So the good news, you actually learned something today. And I also learned something seeing the way NASCAR is using actual wind tunnels during their dyno test. Very cool. And again, I'm sorry if someone tried to convince you that your setup was a wind tunnel. I think it's a very nice setup, it's just not a wind tunnel. Sorry.
But here is what is really bothering me, I worked with a wind tunnel during college. Your setup is not a wind tunnel because it blows into the room. A wind tunnel uses a large fan to pull air through a set of straighteners and then over the car. So the air is pulled into the room through a set of straighteners, then it flows over the car, then into the fan and then it exhausts out of the room. Why? Because you don't want all the swirl coming off the fan going over the car. It creates turbulence and does not simulate the air flow over the car it has when it's moving.
So back to my original question, what is the purpose of this setup? It is an excellent setup to make sure the car cools sufficiently, but that's it. I don't see any way it acts as a wind tunnel and even if it did, what does that do for me on a dyno. I looked into it a little more and the NASCAR guys are using wind tunnel dynos, but in their case the car is in an actual wind tunnel (not a make believe wind tunnel) that produces 200 mph and the car is on a moving surface simulating the road moving beneath the car. The fan they use pulls 2,850,000 cubic feet of air through the room. And they dyno their cars with the hoods close so they are looking at ways to improve the flow to the engine to produce more power.
Personally I would never call your setup a wind tunnel dyno, just a very nice dyno with excellent cooling capabilities. I think it's misleading to use the words wind tunnel in your description. So the good news, you actually learned something today. And I also learned something seeing the way NASCAR is using actual wind tunnels during their dyno test. Very cool. And again, I'm sorry if someone tried to convince you that your setup was a wind tunnel. I think it's a very nice setup, it's just not a wind tunnel. Sorry.
#6
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Join Date: Jun 2011
Location: Silicon Valley, CA
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C63 AMG, P30
Actually I'm a retired Mechanical Engineer and used to work with fans as part of my job. So the velocity coming off the fan is greater, that is correct. But you said the fan had an area of 6 square feet. I'm afraid you are wrong. That would be a fan with a diameter of only 2.76 feet. I think you meant to say the fan was 6 foot in diameter giving it an area of 28.3 square feet. So the velocity coming off the fan is 68 mph. But the problem is this airflow will immediately diffuse into the room and the end result will be an airflow over the car of around half of that, maybe 35 mph. Also, I am aware of the pressure rise across an axial fan. The pressure rise is only 5 inches of water or as I stated before that's only .036 psi. Actually, by my calculations, the stagnation pressure at 68 mph is around .08 psi, so I think maybe your 5 inches is a little low or possibly the fan is bigger than 6 foot in diameter (more like 7 feet in diameter). The speed of the air required to give only 5 inches of pressure rise would be 45 mph. But again, it will diffuse quickly and the resulting pressure inside the chamber will basically be ambient.
But here is what is really bothering me, I worked with a wind tunnel during college. Your setup is not a wind tunnel because it blows into the room. A wind tunnel uses a large fan to pull air through a set of straighteners and then over the car. So the air is pulled into the room through a set of straighteners, then it flows over the car, then into the fan and then it exhausts out of the room. Why? Because you don't want all the swirl coming off the fan going over the car. It creates turbulence and does not simulate the air flow over the car it has when it's moving.
So back to my original question, what is the purpose of this setup? It is an excellent setup to make sure the car cools sufficiently, but that's it. I don't see any way it acts as a wind tunnel and even if it did, what does that do for me on a dyno. I looked into it a little more and the NASCAR guys are using wind tunnel dynos, but in their case the car is in an actual wind tunnel (not a make believe wind tunnel) that produces 200 mph and the car is on a moving surface simulating the road moving beneath the car. The fan they use pulls 2,850,000 cubic feet of air through the room. And they dyno their cars with the hoods close so they are looking at ways to improve the flow to the engine to produce more power.
Personally I would never call your setup a wind tunnel dyno, just a very nice dyno with excellent cooling capabilities. I think it's misleading to use the words wind tunnel in your description. So the good news, you actually learned something today. And I also learned something seeing the way NASCAR is using actual wind tunnels during their dyno test. Very cool. And again, I'm sorry if someone tried to convince you that your setup was a wind tunnel. I think it's a very nice setup, it's just not a wind tunnel. Sorry.
But here is what is really bothering me, I worked with a wind tunnel during college. Your setup is not a wind tunnel because it blows into the room. A wind tunnel uses a large fan to pull air through a set of straighteners and then over the car. So the air is pulled into the room through a set of straighteners, then it flows over the car, then into the fan and then it exhausts out of the room. Why? Because you don't want all the swirl coming off the fan going over the car. It creates turbulence and does not simulate the air flow over the car it has when it's moving.
So back to my original question, what is the purpose of this setup? It is an excellent setup to make sure the car cools sufficiently, but that's it. I don't see any way it acts as a wind tunnel and even if it did, what does that do for me on a dyno. I looked into it a little more and the NASCAR guys are using wind tunnel dynos, but in their case the car is in an actual wind tunnel (not a make believe wind tunnel) that produces 200 mph and the car is on a moving surface simulating the road moving beneath the car. The fan they use pulls 2,850,000 cubic feet of air through the room. And they dyno their cars with the hoods close so they are looking at ways to improve the flow to the engine to produce more power.
Personally I would never call your setup a wind tunnel dyno, just a very nice dyno with excellent cooling capabilities. I think it's misleading to use the words wind tunnel in your description. So the good news, you actually learned something today. And I also learned something seeing the way NASCAR is using actual wind tunnels during their dyno test. Very cool. And again, I'm sorry if someone tried to convince you that your setup was a wind tunnel. I think it's a very nice setup, it's just not a wind tunnel. Sorry.
#7
Super Member
Again, my apologies to the OP. I really didn't set out to discredit him, but the more I looked at his setup, I realized it was just misleading to call it a wind tunnel. Some people would call it Marketing, I call it misleading. I'll give the OP the benefit of the doubt that he didn't realize how a real wind tunnel worked. And the way I asked the first questions about the pressure rise across the axial fan was purposely vague to see where he was coming from. And it's obvious I miss my job. Now that I'm retired I find it challenging to find something I can actually analyze. You can only play so many rounds of golf per year!!!
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glennhl (09-05-2016)
#9
Former Vendor of MBWorld
Thread Starter
It takes 5280 CFM to move air at 60 MPH through a 1 foot opening. If you have 5280 CFM and move the air through a 2' square hole it will travel at 30MPH. A fan that moves 169,000 CFM would move air through a 1' square opening at 1920 MPH. Our fan has an outlet size of 4' by 3' so that equates to 12 square feet which works out to a potential of 160 MPH. This is the airspeed out of the duct work on ihefront of our fan.
Now that is assuming that you have no duct work with that fan, which is not the case with us. Our air comes through an inlet in our roof that measures 4' by 18'. It goes through a dog box which creates a tight turn, down a chute and then makes another turn into the fan. We have a lot of duct work in our system. Now this is why our fan operates at a high static pressure. The static pressure is the amount of velocity that the fan can create and it allows it to overcome all of that duct work while maintaining it's CFM.
To simplify the terms CFM can be compared to horsepower in a car and static pressure can be compared torque. We have 3 very large exhaust fans at the end of the room. They are very high CFM fans as well but they operate at a much lower static pressure. The duct work for these fans lowers the CFM performance because they do not have the same velocity as the front fan. These fans are used to clean the dirty air from the room. When these fans operate by themselves without the front fan there is a lot of movement in the room on it's own but they do not create the velocity like the fan in the front.
It is true that we do not have that much air flowing at that speed through the entire room, but that is not what we are attempting to do. We are simulating air into the engine, radiator, intercoolers and all the heat exchangers in the car so that we can simulate road conditions. As the car on the dyno goes faster, so does the airspeed from our fan. We have the airspeed from the fan limited to 130 and we have a separate computer system that controls that. The fan outlet is directly in front of our test car.
Like I said I am a very poor teacher, mostly because I don't really have the patience that a teacher needs. You seem to have a lot of patience, unlike me. Since you are retired and obviously into this stuff why don't you come on by and I will be happy to show it all to you in person. I know it says you live in Az but it may be worth the 5 hour drive.
It took me almost a year of research into how I can feasibly simulate airspeed in front of the car in order to simulate what an engine experiences on the street. I am by no means an engineer and when I started the research I thought that CFM was CFM, I had never heard of static pressure and had no idea what effects any type of duct would have on my fans. Our airspeed has been measured and I assure you that it is not 24MPH. The tested airspeed after the installation at the fans outlet is 13541.33LFM so we are losing some CFM somewhere in the set up but not much.
NASCAR WIND TUNNEL-
The wind tunnel you are referring is probably a rolling road wind tunnel. These are closed loop wind tunnels used for testing aerodynamics. They don't run a car on a dyno in this type of wind tunnel for the simple reason that the air gets contaminated. Since the system is closed loop the air that goes past the car makes its way around and goes past the car again. If you added the exhaust gas to the air flow then that air would find it's way back into the engine but that's contaminated air now. CARB attempted to do tests in a similar way to this and they had the exhaust gas routed through pipes to keep the air in the system clean. What they found was that air is contaminated from many of the components in the car, not just the tailpipes. That is why one of the CARB tests now is the level of contaminants in the room that are outside of the tailpipe exhaust gases.
Now that is assuming that you have no duct work with that fan, which is not the case with us. Our air comes through an inlet in our roof that measures 4' by 18'. It goes through a dog box which creates a tight turn, down a chute and then makes another turn into the fan. We have a lot of duct work in our system. Now this is why our fan operates at a high static pressure. The static pressure is the amount of velocity that the fan can create and it allows it to overcome all of that duct work while maintaining it's CFM.
To simplify the terms CFM can be compared to horsepower in a car and static pressure can be compared torque. We have 3 very large exhaust fans at the end of the room. They are very high CFM fans as well but they operate at a much lower static pressure. The duct work for these fans lowers the CFM performance because they do not have the same velocity as the front fan. These fans are used to clean the dirty air from the room. When these fans operate by themselves without the front fan there is a lot of movement in the room on it's own but they do not create the velocity like the fan in the front.
It is true that we do not have that much air flowing at that speed through the entire room, but that is not what we are attempting to do. We are simulating air into the engine, radiator, intercoolers and all the heat exchangers in the car so that we can simulate road conditions. As the car on the dyno goes faster, so does the airspeed from our fan. We have the airspeed from the fan limited to 130 and we have a separate computer system that controls that. The fan outlet is directly in front of our test car.
Like I said I am a very poor teacher, mostly because I don't really have the patience that a teacher needs. You seem to have a lot of patience, unlike me. Since you are retired and obviously into this stuff why don't you come on by and I will be happy to show it all to you in person. I know it says you live in Az but it may be worth the 5 hour drive.
It took me almost a year of research into how I can feasibly simulate airspeed in front of the car in order to simulate what an engine experiences on the street. I am by no means an engineer and when I started the research I thought that CFM was CFM, I had never heard of static pressure and had no idea what effects any type of duct would have on my fans. Our airspeed has been measured and I assure you that it is not 24MPH. The tested airspeed after the installation at the fans outlet is 13541.33LFM so we are losing some CFM somewhere in the set up but not much.
NASCAR WIND TUNNEL-
The wind tunnel you are referring is probably a rolling road wind tunnel. These are closed loop wind tunnels used for testing aerodynamics. They don't run a car on a dyno in this type of wind tunnel for the simple reason that the air gets contaminated. Since the system is closed loop the air that goes past the car makes its way around and goes past the car again. If you added the exhaust gas to the air flow then that air would find it's way back into the engine but that's contaminated air now. CARB attempted to do tests in a similar way to this and they had the exhaust gas routed through pipes to keep the air in the system clean. What they found was that air is contaminated from many of the components in the car, not just the tailpipes. That is why one of the CARB tests now is the level of contaminants in the room that are outside of the tailpipe exhaust gases.
Last edited by Staff@WORLD; 09-05-2016 at 03:04 AM.
#10
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Join Date: Jun 2008
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2012 P31 C63 Coupe Trackrat, 2019 GLE63S Coupe Beast
What I learned today:
1) glennhl is really smart and has a lot of time on his hands, so don't get in an argument with him because I'll lose
2) the new World dyno is called a 'wind tunnel', but is actually not in the normal sense of the phrase, because there are no aerodynamics being tested
3) World has built a really cool dyno, and seems to be state-of-the-art in tuning and cooling, which is pretty neat. I want one.
4) World should probably call it something different, but whatever
Is it possible that everyone comes out winning here? Can't we all just get along.....
1) glennhl is really smart and has a lot of time on his hands, so don't get in an argument with him because I'll lose
2) the new World dyno is called a 'wind tunnel', but is actually not in the normal sense of the phrase, because there are no aerodynamics being tested
3) World has built a really cool dyno, and seems to be state-of-the-art in tuning and cooling, which is pretty neat. I want one.
4) World should probably call it something different, but whatever
Is it possible that everyone comes out winning here? Can't we all just get along.....
The following 2 users liked this post by BLKROKT:
507OverBiturbo (09-05-2016),
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#11
Super Member
It takes 5280 CFM to move air at 60 MPH through a 1 foot opening. If you have 5280 CFM and move the air through a 2' square hole it will travel at 30MPH. A fan that moves 169,000 CFM would move air through a 1' square opening at 1920 MPH. Our fan has an outlet size of 4' by 3' so that equates to 12 square feet which works out to a potential of 160 MPH. This is the airspeed out of the duct work on ihefront of our fan.
Now that is assuming that you have no duct work with that fan, which is not the case with us. Our air comes through an inlet in our roof that measures 4' by 18'. It goes through a dog box which creates a tight turn, down a chute and then makes another turn into the fan. We have a lot of duct work in our system. Now this is why our fan operates at a high static pressure. The static pressure is the amount of velocity that the fan can create and it allows it to overcome all of that duct work while maintaining it's CFM.
To simplify the terms CFM can be compared to horsepower in a car and static pressure can be compared torque. We have 3 very large exhaust fans at the end of the room. They are very high CFM fans as well but they operate at a much lower static pressure. The duct work for these fans lowers the CFM performance because they do not have the same velocity as the front fan. These fans are used to clean the dirty air from the room. When these fans operate by themselves without the front fan there is a lot of movement in the room on it's own but they do not create the velocity like the fan in the front.
It is true that we do not have that much air flowing at that speed through the entire room, but that is not what we are attempting to do. We are simulating air into the engine, radiator, intercoolers and all the heat exchangers in the car so that we can simulate road conditions. As the car on the dyno goes faster, so does the airspeed from our fan. We have the airspeed from the fan limited to 130 and we have a separate computer system that controls that. The fan outlet is directly in front of our test car.
Like I said I am a very poor teacher, mostly because I don't really have the patience that a teacher needs. You seem to have a lot of patience, unlike me. Since you are retired and obviously into this stuff why don't you come on by and I will be happy to show it all to you in person. I know it says you live in Az but it may be worth the 5 hour drive.
It took me almost a year of research into how I can feasibly simulate airspeed in front of the car in order to simulate what an engine experiences on the street. I am by no means an engineer and when I started the research I thought that CFM was CFM, I had never heard of static pressure and had no idea what effects any type of duct would have on my fans. Our airspeed has been measured and I assure you that it is not 24MPH. The tested airspeed after the installation at the fans outlet is 13541.33LFM so we are losing some CFM somewhere in the set up but not much.
NASCAR WIND TUNNEL-
The wind tunnel you are referring is probably a rolling road wind tunnel. These are closed loop wind tunnels used for testing aerodynamics. They don't run a car on a dyno in this type of wind tunnel for the simple reason that the air gets contaminated. Since the system is closed loop the air that goes past the car makes its way around and goes past the car again. If you added the exhaust gas to the air flow then that air would find it's way back into the engine but that's contaminated air now. CARB attempted to do tests in a similar way to this and they had the exhaust gas routed through pipes to keep the air in the system clean. What they found was that air is contaminated from many of the components in the car, not just the tailpipes. That is why one of the CARB tests now is the level of contaminants in the room that are outside of the tailpipe exhaust gases.
Now that is assuming that you have no duct work with that fan, which is not the case with us. Our air comes through an inlet in our roof that measures 4' by 18'. It goes through a dog box which creates a tight turn, down a chute and then makes another turn into the fan. We have a lot of duct work in our system. Now this is why our fan operates at a high static pressure. The static pressure is the amount of velocity that the fan can create and it allows it to overcome all of that duct work while maintaining it's CFM.
To simplify the terms CFM can be compared to horsepower in a car and static pressure can be compared torque. We have 3 very large exhaust fans at the end of the room. They are very high CFM fans as well but they operate at a much lower static pressure. The duct work for these fans lowers the CFM performance because they do not have the same velocity as the front fan. These fans are used to clean the dirty air from the room. When these fans operate by themselves without the front fan there is a lot of movement in the room on it's own but they do not create the velocity like the fan in the front.
It is true that we do not have that much air flowing at that speed through the entire room, but that is not what we are attempting to do. We are simulating air into the engine, radiator, intercoolers and all the heat exchangers in the car so that we can simulate road conditions. As the car on the dyno goes faster, so does the airspeed from our fan. We have the airspeed from the fan limited to 130 and we have a separate computer system that controls that. The fan outlet is directly in front of our test car.
Like I said I am a very poor teacher, mostly because I don't really have the patience that a teacher needs. You seem to have a lot of patience, unlike me. Since you are retired and obviously into this stuff why don't you come on by and I will be happy to show it all to you in person. I know it says you live in Az but it may be worth the 5 hour drive.
It took me almost a year of research into how I can feasibly simulate airspeed in front of the car in order to simulate what an engine experiences on the street. I am by no means an engineer and when I started the research I thought that CFM was CFM, I had never heard of static pressure and had no idea what effects any type of duct would have on my fans. Our airspeed has been measured and I assure you that it is not 24MPH. The tested airspeed after the installation at the fans outlet is 13541.33LFM so we are losing some CFM somewhere in the set up but not much.
NASCAR WIND TUNNEL-
The wind tunnel you are referring is probably a rolling road wind tunnel. These are closed loop wind tunnels used for testing aerodynamics. They don't run a car on a dyno in this type of wind tunnel for the simple reason that the air gets contaminated. Since the system is closed loop the air that goes past the car makes its way around and goes past the car again. If you added the exhaust gas to the air flow then that air would find it's way back into the engine but that's contaminated air now. CARB attempted to do tests in a similar way to this and they had the exhaust gas routed through pipes to keep the air in the system clean. What they found was that air is contaminated from many of the components in the car, not just the tailpipes. That is why one of the CARB tests now is the level of contaminants in the room that are outside of the tailpipe exhaust gases.
Thank you so much for your explanation, makes sense to me. However, you do state that you are pushing the main fan flow through a 4' x 3' opening and it could produce 160 mph, but that's only if it takes just 5" water to flow through that opening. I'm guessing the pressure drop across that opening is much greater especially with the big dump loss exiting the box. I assume you have measured the actual velocity coming out of the box and I'm betting it's a lot less than 160 mph. But I wouldn't be surprised to see you get 100 mph out of the fan. But when it dumps into the room it will quickly diffuse. Have you measured the actual velocity at the vehicle? I'd recommend you pick up a cheap anemometer and measure the velocity out of the fan and at the car, that would give you some more selling points.
Of course, it's still not an actual wind tunnel because as I stated it is pushing air into the room, not sucking it out. So you end up with the swirl coming out of the fan. But with all that, I think what you have done is outstanding, extremely nice!!! It's the best dyno setup I've seen. Well, at least an affordable one. The NASCAR one I read about was owned by Gene Haas (Tony Stewart) and it is a rolling road wind tunnel with a dyno.
http://www.autoblog.com/2007/04/17/w...s-you-can-get/
Again, thanks for all your information and I really like what you have done. It will give you some options that will be nice when dynoing a car. I get over that way a few times per year, so I'll stop by and say hi.
EDIT: I just noticed you have measured some velocities as you stated you got 13541 LFM out of the fan, that's 154 mph. So that is outstanding. With that fan exit velocity, what kind of speed to you have hitting the front of the vehicle? Thanks.
Last edited by glennhl; 09-05-2016 at 01:09 PM.
#12
Super Member
What I learned today:
1) glennhl is really smart and has a lot of time on his hands, so don't get in an argument with him because I'll lose
2) the new World dyno is called a 'wind tunnel', but is actually not in the normal sense of the phrase, because there are no aerodynamics being tested
3) World has built a really cool dyno, and seems to be state-of-the-art in tuning and cooling, which is pretty neat. I want one.
4) World should probably call it something different, but whatever
Is it possible that everyone comes out winning here? Can't we all just get along.....
1) glennhl is really smart and has a lot of time on his hands, so don't get in an argument with him because I'll lose
2) the new World dyno is called a 'wind tunnel', but is actually not in the normal sense of the phrase, because there are no aerodynamics being tested
3) World has built a really cool dyno, and seems to be state-of-the-art in tuning and cooling, which is pretty neat. I want one.
4) World should probably call it something different, but whatever
Is it possible that everyone comes out winning here? Can't we all just get along.....
#13
Super Member
All true statements except for that first one. Glennhl is NOT that smart! I just have a lot of time on my hands. And just so everyone knows, I wasn't trying to win an argument, just understand what this new dyno was all about. The OP turned out to be a very nice and patient person and I wish him all the luck in the world on his very nice dyno installation. Thanks.
#14
Super Member
It occurred to me that you could put a de-swirler on the exit of the fan. It would straighten air flow at a set fan speed. You could actually buy a couple of de-swirler plates for different fan speeds.
#16
Super Member
That is NOT a wind tunnel. It is a closed room with a tiny fan in it with no pass through whatsoever! Also you lied during the most recent smoking tire video when you said you have the only wind tunnel dyno in the country (flat out lie, many OEMs have them in house). And that's completely ignoring the fact that it's not a wind tunnel to begin with. Stop making false claims.
For your reference here are just a few examples of real wind tunnels below
For your reference here are just a few examples of real wind tunnels below