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# What Width/Diameter means?

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I have a question if anyone know!

I´m working in a turbofan for know the "on-design" and when I search I found this parameter: Width/Diameter!

Anyone can tell me what this means? And for what can I use this?

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Hi there?

The definitions of "width" and "diameter" are easy to find in Wikipedia. I'm surprised you haven't already looked there.

The attached drawing shows two objects, a circle and a rectangle. The "width" of an object is the LENGTH from one side of the object to the other side.

The "diameter" applies only to circles, or objects that have circle cross-section, like a cylinder or pipe. It is the LENGTH of a line that goes through the center of the circle. The "diameter" of a circle is the SAME as the "width" of the circle.

These ideas are very useful everywhere, especially in construction. If you are laying a pipeline, you must know the diameter of the pipe. If you want to move an appliance into a kitchen, you must first know the width of the kitchen door.

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Hi there?

The definitions of "width" and "diameter" are easy to find in Wikipedia. I'm surprised you haven't already looked there.

The attached drawing shows two objects, a circle and a rectangle. The "width" of an object is the LENGTH from one side of the object to the other side.

The "diameter" applies only to circles, or objects that have circle cross-section, like a cylinder or pipe. It is the LENGTH of a line that goes through the center of the circle. The "diameter" of a circle is the SAME as the "width" of the circle.

These ideas are very useful everywhere, especially in construction. If you are laying a pipeline, you must know the diameter of the pipe. If you want to move an appliance into a kitchen, you must first know the width of the kitchen door.

But what I want to ask it´s the reason between the width and diameter because I found a web page where they have this reason.

In this page have one parameter: (width/diameter) = 'a number' ---> I don´t understand what this relation means!

In a turbofan we have the Fan diameter and I understand this but in a turbofan I don´t see why this relation between those two.

I hope you understand me better now.

Sorry if my question was poorly made.

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... In this page have one parameter: (width/diameter) = 'a number' ---> I don´t understand what this relation means! ...
I'm very sure that when they use "width/diameter" they do not mean "width divided by diameter".

They mean the "width" where the component is not necessarily a circle, OR the "diameter" if the component is a circle or cylinder.

So, if they give a value of 42 (inches) for a turbine fan, that's 42 (inches) diameter.

But if it is for a landing gear truck, that's 42 (inches) width.

Does this help?

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But what I want to ask it´s the reason between the width and diameter because I found a web page where they have this reason.

In this page have one parameter: (width/diameter) = 'a number' ---> I don´t understand what this relation means!

The page you reference has a column titled “Width/Diameter [in]”. This means, I’m fairly certain, "width, as a diameter, in inches", the diameter of a circle, in inches, that can enclose all cross sections of the outside of the jet engine. That is, if you had a hoop with the specified inside diameter, you could pass the dismounted engine through it.

It has another column labeled “Fan Diameter [in]”. This means the diameter of the intake fan blades, in inches.

As the fan blades of a jet engine are enclosed in it, “Fan Diameter” must always be less that “Width/Diameter”. Checking the table, it always is, by from 5 to 20 inches, about what I expect of jet engines of various sizes.

I believe you were confused, João, by the use of the “/” to mean “or” or “also called”, rather than the arithmetic operation of division. The numbers in the “Width/Diameter [in]” column are distances in inches, not the ratio (relation) “width divided by diameter.”

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Hi!

Ya, now I look for the units and understand this... :Glasses:

I don´t see them and let me confused because if don´t have units this ratio are dimensionless. This was my confusion.

Thanks for all

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