Time to go Stage II!
- Thread starter Alky V6
- Start date
The best runner entrance radius is an elliptical flare type radius. When done right, they do take up a lot of room. I want to see if this shape is feasable for me to use with my manifold design. Mainly, the question is, do I have enough room to use properly shaped elliptical flares for my runner entrances?
I've decided that I'm going to be making the runner entrances myself using my manual milling machine and my rotary indexer. My first mission is going to learn to understand the math involved in coming up with a properly sized elliptical flare radius. What is the definition of an elliptical flare or curve?
http://www.mathopenref.com/ellipse.html
I've decided that I'm going to be making the runner entrances myself using my manual milling machine and my rotary indexer. My first mission is going to learn to understand the math involved in coming up with a properly sized elliptical flare radius. What is the definition of an elliptical flare or curve?
http://www.mathopenref.com/ellipse.html
General equation of an ellipse. How do you use this to come up with an elliptical flare radius runner entrance? I am very rusty on my math.
http://www.mathopenref.com/coordgeneralellipse.html
http://www.mathopenref.com/coordgeneralellipse.html
Here's a post that shows some important variables for coming up with different flare types.
http://www.theturboforums.com/threads/361799-Intake-manifold-design?p=1814925&viewfull=1#post1814925
http://www.theturboforums.com/threads/361799-Intake-manifold-design?p=1814925&viewfull=1#post1814925
First thing is to come up with are some known measurements that can be used in any equations involved in plotting out the elliptical flare.
The calculated diameter of the runner entrance is 2.65" after the entrance flare shape. It is a rectangular entrance, but converting the height and width of the entrance into a circle, that's what I come up with.
The height of the runner entrance flare shape will be 75% of the calculated runner entrance flare shape exit diameter. So the height of the runner entrance will be 1.99". That's pretty high. Yikes.
The next variable to figure out is, what does the diameter at the entry of the flare opening in relation to the diameter at the exit of the flare opening need to be?
edit: It appears the entry diameter to the flare should be 2.13 times the exit diameter of the flared entrance. The exit is 2.65", so the entrance needs to be 5.64" diameter. 5.64 will need to be converter into a rectangular shape.
The calculated diameter of the runner entrance is 2.65" after the entrance flare shape. It is a rectangular entrance, but converting the height and width of the entrance into a circle, that's what I come up with.
The height of the runner entrance flare shape will be 75% of the calculated runner entrance flare shape exit diameter. So the height of the runner entrance will be 1.99". That's pretty high. Yikes.
The next variable to figure out is, what does the diameter at the entry of the flare opening in relation to the diameter at the exit of the flare opening need to be?
edit: It appears the entry diameter to the flare should be 2.13 times the exit diameter of the flared entrance. The exit is 2.65", so the entrance needs to be 5.64" diameter. 5.64 will need to be converter into a rectangular shape.
Another link that has some interesting information on runner entrances.
http://www.nsxprime.com/forum/showthread.php?t=140378
http://www.nsxprime.com/forum/showthread.php?t=140378
Coming up with the radii variables a and b for the general equation of an ellipse.
2.65 = runner entrance flare shape exit diameter.
5.64 = 2.13 times the runner entrance flare shape exit diameter. This is the entry diameter of the runner entrance flare shape.
5.64 - 2.65 = 2.99 The difference between the flare shape entry diameter and the exit diameter.
2.99 / 2 = 1.495 The difference between the flare shape entry diameter and the exit diameter on each side of the flared entrance.
radius a for the general equation = .75 x 2.65 (75% of the exit diameter of the runner entry flare shape) = 1.990 at C = 0, 0 of the equation.
radius b for the general equation = 1.495 (calculated above) at C = 0, 0.
C = center of a formed elliptical circle plotted on a x,y graph.
Now that we have the radii variables that we can plug into the general equation, we should be able to determine and plot all x and y coordinates along the ellipse curve.
2.65 = runner entrance flare shape exit diameter.
5.64 = 2.13 times the runner entrance flare shape exit diameter. This is the entry diameter of the runner entrance flare shape.
5.64 - 2.65 = 2.99 The difference between the flare shape entry diameter and the exit diameter.
2.99 / 2 = 1.495 The difference between the flare shape entry diameter and the exit diameter on each side of the flared entrance.
radius a for the general equation = .75 x 2.65 (75% of the exit diameter of the runner entry flare shape) = 1.990 at C = 0, 0 of the equation.
radius b for the general equation = 1.495 (calculated above) at C = 0, 0.
C = center of a formed elliptical circle plotted on a x,y graph.
Now that we have the radii variables that we can plug into the general equation, we should be able to determine and plot all x and y coordinates along the ellipse curve.
Now I need to modify the general equation so that I can determine the y coordinate for any given x coordinate along the ellipse curve. Or, vice versa, be able to determine the x coordinate for any given y coordinate along the ellipse curve.
Hmmm.
1 - (x² / a²) = (y² / b²)
How to boil it down further to determine 'y'. I think I'm stuck.
Maybe this;
y² x b² = z ?
√z = y ?
Arrg.
I broke out the DesignCAD program. This will be much easier. Now, all I have to do is use the dimensioning features of the program to come up with the coordinate locations at particular intervals along the x or y axis of the elliptical curve.
Too late. I've already put together the list of coordinates.PM Jerryl on the math and engineering stuff Donnie. I think he'd be interested in the math as well as helping you out.
