Balcony Wind issues

In general does it seem to make a difference where you are located (high vs lower deck) wind wise on your balcony. This next cruise we were not able to get our favorite aft location, so wondering when underway if a lower deck would be less windy or not?

Hard to say, because we have not been in different cabins on the same cruise to say if it is different. However, it would seem logical that the wind would be about the same no matter what deck you are on.

There are many other factors that will influence the amount of wind as much or more than the deck height. Have you considered an aft cabin?

There are many other factors that will influence the amount of wind as much or more than the deck height. Have you considered an aft cabin?

If you read the OP's post again, you will see they said they couldn't get their favored aft cabin location.

Thoughts...

• Where are you cruising too? Glacier viewing is popular for balconies.
  
• I found balconies too windy for me... I now look for an oceanview with the biggest windows.
  

From OP: we are doing Hawaii to Sydney Au. have cruised many times, only once before on the "side" of the Ship. Noticeable more wind, just curious if the lower decks have less. Balcony is a must, if only for fresh air- but would like to enjoy watching the view w/o a wind tunnel. If no difference between upper and lower will get the best deal regardless of location.

Wind speed increases with height. How much windier it would be would depend on which deck you're on.

https://en.m.wikipedia.org/wiki/Wind_gradient

The aft cabins, assuming that you aren't in a strong following wind, are going to be less breezy because they're in the slip. Basically, the aft cabins are drafting.

Aft is best, could not get one this cruise. That lower would be less windy from exp. Walking around on decks.

Wind speed increases with height. How much windier it would be would depend on which deck you're on.

 

https://en.m.wikipedia.org/wiki/Wind_gradient

 

The aft cabins, assuming that you aren't in a strong following wind, are going to be less breezy because they're in the slip. Basically, the aft cabins are drafting.

Yes, but I doubt it is particularly noticed by humans between say, 30 feet above the water, which would be about the lowest balcony cabin, and say 90 or 100 feet above the water, which would be about the highest balcony cabin. I would think the difference at those two levels, given the ship will be moving no more than 20 or so mph, would be only a couple of mph, max.

Yes, but I doubt it is particularly noticed by humans between say, 30 feet above the water, which would be about the lowest balcony cabin, and say 90 or 100 feet above the water, which would be about the highest balcony cabin. I would think the difference at those two levels, given the ship will be moving no more than 20 or so mph, would be only a couple of mph, max.

Absolutely, and your "couple of mph" would be very generous. The fact that most of the "breeze" is generated by the ship moving through the air, not the air moving over the land, the shear forces will be nearly consistent over the entire surface of the ship.

I would say that the side of the ship you are on any one day is a more critical factor than deck level. However, the "best" side on any one day can vary depending on the prevailing winds (toward aft of ship, headwinds, starboard or port, etc.) AND the direction of the ship in relation to the winds. Just think about deck walking - some days it is windier on a different side. On my last cruise most days everything was fine, but on one or two days (long cruise) the strength of the wind made it all but impossible to even open the door a crack.

Wind speed increases with height. How much windier it would be would depend on which deck you're on.

 

https://en.m.wikipedia.org/wiki/Wind_gradient

 

The aft cabins, assuming that you aren't in a strong following wind, are going to be less breezy because they're in the slip. Basically, the aft cabins are drafting.

The difference in wind speed between lowest and highest balcony decks on a ship is unlikely to be detectable. The point of a balcony cabin is to experience being at sea -- and wind is an essential part of that experience. If it is a matter of concern, better get an ocean view.

The difference in wind speed between lowest and highest balcony decks on a ship is unlikely to be detectable. The point of a balcony cabin is to experience being at sea -- and wind is an essential part of that experience. If it is a matter of concern, better get an ocean view.

Wind speed increases logarithmically with an increase in height. Unless it's super calm, there should be a noticeable difference between the promenade deck and the cabins up by the Crow's Nest. A 10m (33 foot) rise is going to give you a wind speed increase of almost 27 mph (12 m/sec.) Please refer to the chart in the article at the link. Bear in mind that the calculations in the article are based on a level, grassy field. The log multiplier is higher if the "ground" is uneven - like the ocean would be.

http://belfortinstrument.com/height-wind-measurements-ground/

Wind speed increases logarithmically with an increase in height. Unless it's super calm, there should be a noticeable difference between the promenade deck and the cabins up by the Crow's Nest. A 10m (33 foot) rise is going to give you a wind speed increase of almost 27 mph (12 m/sec.) Please refer to the chart in the article at the link. Bear in mind that the calculations in the article are based on a level, grassy field. The log multiplier is higher if the "ground" is uneven - like the ocean would be.

 

http://belfortinstrument.com/height-wind-measurements-ground/

The first sentence of this article says it all:

Due to surface drag, even over seemingly smooth surfaces laminar wind speed decreases to near Zero at the surface of the earth.

Where the wind encounters a solid object, there is friction and shear force, and this decreases the farther away from the surface (hence the higher you are above ground). However, as I've said, most "apparent" wind on a moving ship is caused by the ship (the surface, whether the hull at the waterline, or the radar mast) moving through the air. Therefore, if you are standing on your balcony on deck 5, or at the crows nest, you are still less than 2 meters above the "surface", and most likely closer, since the bulkheads and the balcony above are also "surfaces".

The first sentence of this article says it all:

 

Due to surface drag, even over seemingly smooth surfaces laminar wind speed decreases to near Zero at the surface of the earth.

 

Where the wind encounters a solid object, there is friction and shear force, and this decreases the farther away from the surface (hence the higher you are above ground). However, as I've said, most "apparent" wind on a moving ship is caused by the ship (the surface, whether the hull at the waterline, or the radar mast) moving through the air. Therefore, if you are standing on your balcony on deck 5, or at the crows nest, you are still less than 2 meters above the "surface", and most likely closer, since the bulkheads and the balcony above are also "surfaces".

I think that you are misinterpreting the term surface. It's considered to be 5m above sea level (nominal) in the article. It's not referring to "any surface." Otherwise, there wouldn't be any difference in wind speed between floors in a building. There is. It follows the equation in the article very closely.

If there weren't much of a differential, the only sail on a sailboat that would work would be the jib. :)

I think that you are misinterpreting the term surface. It's considered to be 5m above sea level (nominal) in the article. It's not referring to "any surface." Otherwise, there wouldn't be any difference in wind speed between floors in a building. There is. It follows the equation in the article very closely.

 

If there weren't much of a differential, the only sail on a sailboat that would work would be the jib. :)

No, not misinterpreting the term surface. The slowing of the wind is caused by surface drag, which happens anytime a fluid flows past a solid. So, yes, the wind will decrease in velocity the closer you get to a surface parallel to the flow. No denying this. However, when the winds are 5-10 knots, and the ship is sailing t 18-20 knots, the small decrease in actual wind between say 10m and 25m above sea level (balconies a few decks apart) is greatly offset by the apparent wind generated by the ship's motion, and what I'm saying is that while the same surface drag applies to the ship's decks and bulkheads that are parallel to the wind, since you are just about on these surfaces, there is no discernible decrease in this generated wind.

No, not misinterpreting the term surface. The slowing of the wind is caused by surface drag, which happens anytime a fluid flows past a solid. So, yes, the wind will decrease in velocity the closer you get to a surface parallel to the flow. No denying this. However, when the winds are 5-10 knots, and the ship is sailing t 18-20 knots, the small decrease in actual wind between say 10m and 25m above sea level (balconies a few decks apart) is greatly offset by the apparent wind generated by the ship's motion, and what I'm saying is that while the same surface drag applies to the ship's decks and bulkheads that are parallel to the wind, since you are just about on these surfaces, there is no discernible decrease in this generated wind.

Fair enough. We're going to have to sail with an anemometer-stick held out from the balcony (like a selfie-stick for wind) at some point to make an experimental determination. :D

If there weren't much of a differential, the only sail on a sailboat that would work would be the jib. :)

On the other hand, the mainsail is normally the largest and lowest sail on a vessel and, unless square-rigged, normally gets narrower as it gets higher. Guess I'll have to re-rig my boat so the boom is at the top of the mast where there's more wind! :D

I think that you are misinterpreting the term surface. It's considered to be 5m above sea level (nominal) in the article. It's not referring to "any surface." Otherwise, there wouldn't be any difference in wind speed between floors in a building. There is. It follows the equation in the article very closely.

 

If there weren't much of a differential, the only sail on a sailboat that would work would be the jib. :)

In the context of this discussion: regarding perceived wind on different decks, the data shown on your graph pretty well demonstrates the minimal effect height would have. The lowest exposed deck on a cruise ship has to be about 10 meters above sea level - at that point and above, the line comes close to being flat: perhaps one or two knots of wind speed from the lowest to the uppermost exposed deck- which is trivialized by the 15 to 20 knots of ships motion.

No...deck level doesn't really matter. Standing AT the rail is the windiest. Sitting in a chair by your balcony door is hardly windy at all.

I'm just going to give up now. The logarithmic graph indicates a very fast attack angle.

I bet kids today don't even learn modulo math. ;)

On the other hand, the mainsail is normally the largest and lowest sail on a vessel and, unless square-rigged, normally gets narrower as it gets higher. Guess I'll have to re-rig my boat so the boom is at the top of the mast where there's more wind! :D

Hang a square rigged sail next time. As soon as the wind picks up, you'll see why mainsails get narrow towards the top of the mast. :)

Off Topic:

Congrats to POA1 for making the 5,000 posts club today!

Off Topic:

 

Congrats to POA1 for making the 5,000 posts club today!

Thanks. The fact that it was on fluid dynamics makes it extra special. :D

Thanks. The fact that it was on fluid dynamics makes it extra special. :D

I think I prefer the fluid dynamics discussed in your landmark thread "Wines and corkage and bars, Oh my!" :D:D:D