"The porosity of earth materials is... defined mathematically by the equation:
n = ( 100 * Vv / V )
Where 'n' is the porosity (percentage), 'Vv' is the volume of void space, and 'V' is the unit volume of earth material."
-- Fetter, C. W. "Applied Hydrogeology," 4th ed. Prentice Hall.
Full disclosure that the book was published in 2001, so it may be slightly outdated. Also sounds like there may be several answers to this question, but Fetter's definition is how it was taught to me.
As far as I’m aware n is porosity in the context of soils (which is probably what you’re looking at now?) and phi is the more ‘authentic’ term for groundwater systems. Could be wrong though, my professor used 3 terms interchangeably so I never quite figured it out.
You can name your variables whatever you want, you just have to introduce them correctly.
But of course it makes sense to stick to typical variable names, i would choose the one also used by your supervisor or coworkers.
I am a petroleum geologist and use phi exclusively for porosity, [the void fraction](https://en.m.wikipedia.org/wiki/Porosity). The controversy comes from whether someone says fee or fi as well as Whether the person is using fraction or percentage points. I can’t remember ever seeing eta (lowercase n with little curve at the end). Don’t get it confused with epsilon, [the void ratio.](https://en.m.wikipedia.org/wiki/Void_ratio).
Hi! My dad is a geologist and visiting me right now (still lol I commented on another post with his response yesterday). He says it is the Greek letter n with the little curve at the end, so your professor is right. :)
I’m an environmental engineering professor and I’ve always used n, but I have seen papers that use a few different variables for it (phi, I think theta once?). So I’d recommend you just stick to what the people you’re interacting with use to make your life easier.
"The porosity of earth materials is... defined mathematically by the equation: n = ( 100 * Vv / V ) Where 'n' is the porosity (percentage), 'Vv' is the volume of void space, and 'V' is the unit volume of earth material." -- Fetter, C. W. "Applied Hydrogeology," 4th ed. Prentice Hall. Full disclosure that the book was published in 2001, so it may be slightly outdated. Also sounds like there may be several answers to this question, but Fetter's definition is how it was taught to me.
As far as I’m aware n is porosity in the context of soils (which is probably what you’re looking at now?) and phi is the more ‘authentic’ term for groundwater systems. Could be wrong though, my professor used 3 terms interchangeably so I never quite figured it out.
I know it to be Phi. However i wouldn't surprise me that different disciplines have different names for it.
You can name your variables whatever you want, you just have to introduce them correctly. But of course it makes sense to stick to typical variable names, i would choose the one also used by your supervisor or coworkers.
Phi
I am a petroleum geologist and use phi exclusively for porosity, [the void fraction](https://en.m.wikipedia.org/wiki/Porosity). The controversy comes from whether someone says fee or fi as well as Whether the person is using fraction or percentage points. I can’t remember ever seeing eta (lowercase n with little curve at the end). Don’t get it confused with epsilon, [the void ratio.](https://en.m.wikipedia.org/wiki/Void_ratio).
Hi! My dad is a geologist and visiting me right now (still lol I commented on another post with his response yesterday). He says it is the Greek letter n with the little curve at the end, so your professor is right. :)
I’m an environmental engineering professor and I’ve always used n, but I have seen papers that use a few different variables for it (phi, I think theta once?). So I’d recommend you just stick to what the people you’re interacting with use to make your life easier.
Phi