Density and moisture ?
This could run and run.
Elements and compounds can have some astonishing properties.
Water has some unique properties - one that is commonly known is that expands as it freezes.
Aviation-wise, it's not only water. Carbon fibre does too.
Merely fascinating until you realise that the A380 has an Aluminium spar in it's Carbon horizontal stabiliser. Don't know how it's dealt with, but I really really hope that they are not bonded together (originally).
My Father was an Aeronautical engineer (back when they were looking at ceramic blades), and I have a friend who he would love to have met - does composite stuff for RR. If I were to tell you too much about intelligent metals, black cars would be parking outside my house!
What are you working on?
Elements and compounds can have some astonishing properties.
Water has some unique properties - one that is commonly known is that expands as it freezes.
Aviation-wise, it's not only water. Carbon fibre does too.
Merely fascinating until you realise that the A380 has an Aluminium spar in it's Carbon horizontal stabiliser. Don't know how it's dealt with, but I really really hope that they are not bonded together (originally).
My Father was an Aeronautical engineer (back when they were looking at ceramic blades), and I have a friend who he would love to have met - does composite stuff for RR. If I were to tell you too much about intelligent metals, black cars would be parking outside my house!
What are you working on?
Oh, and, you're aware of Glycol injection into Merlins etc?
Better than water because the 'latent heat of evaporation' is more effective. Or in simple terms, takes more heat out with it.
I did Naval Architecture, so a bit closer to Aerodynamics than a Mech Eng. So while people still argue about Bernoulli vs. plank theory there is a funny little thing that my Dad told me about.
I did just write a paragraph explaining it, and saying that we never came up with a practical use for it. But then realised that there might well be, so forgive me for the tease!
Better than water because the 'latent heat of evaporation' is more effective. Or in simple terms, takes more heat out with it.
I did Naval Architecture, so a bit closer to Aerodynamics than a Mech Eng. So while people still argue about Bernoulli vs. plank theory there is a funny little thing that my Dad told me about.
I did just write a paragraph explaining it, and saying that we never came up with a practical use for it. But then realised that there might well be, so forgive me for the tease!
My sport has been yacht racing. Other than the heading of the entire boat, we constantly adjust AoA, camber and the longitudinal position of max camber. And sometimes change sails to suit wind speeds. (And twist the sails to allow for what we call wind shear and you might call ground effect).
That can occasionally be bizarre. Most of the time the closer to the water, the slower the wind. Which is lucky because it would be very complicated to twist the sail the other way. But on two occasions (both Autumnal with T inversions) the higher breeze was slower. Very odd, and felt like I was hallucinating. Top of the sails working nicely, bottoms just flapping.
There are always beer fuelled debates about wind density, temp/humidity, and its' effect on forward speed (l/d). Problem is that we are all racing in the same stuff, and with so many other variables it's very hard to quantify - so we don't because getting to the bar first is more important.
But I will agree that a damp day seems to help turbulence/not help laminar flow.
That can occasionally be bizarre. Most of the time the closer to the water, the slower the wind. Which is lucky because it would be very complicated to twist the sail the other way. But on two occasions (both Autumnal with T inversions) the higher breeze was slower. Very odd, and felt like I was hallucinating. Top of the sails working nicely, bottoms just flapping.
There are always beer fuelled debates about wind density, temp/humidity, and its' effect on forward speed (l/d). Problem is that we are all racing in the same stuff, and with so many other variables it's very hard to quantify - so we don't because getting to the bar first is more important.
But I will agree that a damp day seems to help turbulence/not help laminar flow.
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I used the following day-to-day observation to help with the density concept during my PPL training:
1. When boiling water, the vapor rises. Therefore, water vapor (aka moisture) must be lighter than dry air.
Just my $0.02
1. When boiling water, the vapor rises. Therefore, water vapor (aka moisture) must be lighter than dry air.
Just my $0.02
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Funny - I once heard an explanation of operation of a humidifier. Seems that you really don't need a fan to distribute the water vapor. It mixes naturally - Brownian motion - or, if you will, "under its own steam". 
1. When boiling water, the vapor rises. Therefore, water vapor (aka moisture) must be lighter than dry air.
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black cars
thanx for taking the time. I'm involved with C series and L-85 at the production level huge investment going on here in Belfast with dry fibre RTI technology and I have been out to Mexico to try and help with porosity problems with the "Lear" 85 fully-comp fuselage. Have to be a bit careful with confidentiality and all that. The Belfast factory is huge and there have been no end of visiting dignitaries . Some people from Sukhoi came and were caught on the way out with bits of post-cure resin ! At the minute its a grossly labour intensive process but test panels have resisted huge stress loads. Lightning strike , water ingress over time and accident damage are some of the many considerations causing sleepless nights here. Hold on.......someones at the door.......
