What OTW Training have you done today

[Nosmo]

People usually say because you are using a lower stroke rate into a head wind, it should be easier to get the timing right. It usually feels easier to me to set the boat when I am going into a headwind. I suspect when going into a headwind that you get extra stability from the flow of air around the blades and maybe your body. Is that right?

Don't see why air flow around the body and blades would provide stability. Would also expect that since you loose speed the stability provided by the fin would decrease significantly. One spends more time with the blades in water both because the load increases and people usually people lengthen the stroke when going into a head wind. That and the easier timing would provide some stability.
For today that is my long answer.
My short answer is honestly I really don't know.
Have to think about this some more.

[Byron Drachman]

People usually say because you are using a lower stroke rate into a head wind, it should be easier to get the timing right. It usually feels easier to me to set the boat when I am going into a headwind. I suspect when going into a headwind that you get extra stability from the flow of air around the blades and maybe your body. Is that right?

Don't see why air flow around the body and blades would provide stability. Would also expect that since you loose speed the stability provided by the fin would decrease significantly. One spends more time with the blades in water both because the load increases and people usually people lengthen the stroke when going into a head wind. That and the easier timing would provide some stability.
For today that is my long answer.
My short answer is honestly I really don't know.
Have to think about this some more.

Hi Nosmo,

I was thinking of the feathered blades as miniature wings adding to the stability. Spending more time with the blades in the water, hence more stability, into a headwind makes sense. I hadn't thought of that. Funny thing is that I once co-authored an article in fluid dynamics but I did the mathematics part only and I don't have much intuition or experience in that field.

[bloomp]

Anecdotally, I've always had coaches tell me that it's easier to set the boat in a headwind. Why, I'm not sure. But the recommendations of a late square-up and a little more layback have seemed to work. The first obviously because the wind has less time to play with your blade. The second, I have no reasoning for, but again, it just seems to work.

I doubt we truly have a pure headwind. It's usually between a crosswind and headwind, meaning you have to deal with forces that offset the boat more than just forces that slow you down - think about how small the profile of a boat is in the wind, compared to a sail or even a launch. So the amount of "slowing down" you get from the headwind pales in comparison to the degree that the wind can offset the boat when it comes from the side.

When coaching, I tell my rowers to do what I was taught, mostly because I found it to work for me. I've also found that it's a lot easier to row well into a head/head-cross wind than it is to row with a tail/tail-cross wind.

[Byron Drachman]

I did 18K steady state. "Steady state" is code for a leisurely row. The video shows typical conditions I have to deal with. This morning there was some mist, and sometimes I have to stop and take photos of deer, herons, cranes, and other creatures. And a couple of times some fish jumped and disturbed the otherwise glassy water. Don't you hate it when that happens? Life is tough.

[Nosmo]

.... Funny thing is that I once co-authored an article in fluid dynamics but I did the mathematics part only and I don't have much intuition or experience in that field.

Don't feel bad, I did a turbulence experiment for my Ph.D. thesis.
Forgot about this thread and hadn't been thinking about it. I'll see if I can come up with something more insightful.

[Byron Drachman]

.... Funny thing is that I once co-authored an article in fluid dynamics but I did the mathematics part only and I don't have much intuition or experience in that field.

Don't feel bad, I did a turbulence experiment for my Ph.D. thesis.
Forgot about this thread and hadn't been thinking about it. I'll see if I can come up with something more insightful.

HI Paul, I agree it makes sense to delay the squaring in a headwind.

Hi Nosmo,

I came across this. So what I was thinking is called ground effect.

http://www.phys.washington.edu/users/je ... fscbrb.htm

During the recovery if the blades are off the water you will get a small aerodynamic lift force acting on the spoon due to the angle of attack of the spoon on the feather. If the spoon is very close to the water you seem to get a "ground effect" enhanced lift similar to that experienced by aircraft operating very close to the ground. The closer you get to the water the greater the lift and that side of the boat tends to rise, a nice negative feedback system that gives a reduced version of skimming along the water without actually having to touch the surface.

[Bob S.]

HI Paul, I agree it makes sense to delay the squaring in a headwind.

Hi Nosmo,

I came across this. So what I was thinking is called ground effect.

http://www.phys.washington.edu/users/je ... fscbrb.htm

During the recovery if the blades are off the water you will get a small aerodynamic lift force acting on the spoon due to the angle of attack of the spoon on the feather. If the spoon is very close to the water you seem to get a "ground effect" enhanced lift similar to that experienced by aircraft operating very close to the ground. The closer you get to the water the greater the lift and that side of the boat tends to rise, a nice negative feedback system that gives a reduced version of skimming along the water without actually having to touch the surface.

I can see it now. Byron in a homemade craft with a circle of oar blades under the hull, flying along as a human propelled hovercraft. The tricky part is getting that first couple of inches above the water surface.

Actually there has been a successful boat that was almost as unlikely. As I remember, it had a regular propeller driven by bicycle type pedals and the main part of the hull cleared the water with just a special fin submerged. I believe that he was doing about 15 knots. This was at Long Beach about 15 years ago.

Bob S.

[Byron Drachman]

HI Paul, I agree it makes sense to delay the squaring in a headwind.

Hi Nosmo,

I came across this. So what I was thinking is called ground effect.

http://www.phys.washington.edu/users/je ... fscbrb.htm

During the recovery if the blades are off the water you will get a small aerodynamic lift force acting on the spoon due to the angle of attack of the spoon on the feather. If the spoon is very close to the water you seem to get a "ground effect" enhanced lift similar to that experienced by aircraft operating very close to the ground. The closer you get to the water the greater the lift and that side of the boat tends to rise, a nice negative feedback system that gives a reduced version of skimming along the water without actually having to touch the surface.

I can see it now. Byron in a homemade craft with a circle of oar blades under the hull, flying along as a human propelled hovercraft. The tricky part is getting that first couple of inches above the water surface.

Actually there has been a successful boat that was almost as unlikely. As I remember, it had a regular propeller driven by bicycle type pedals and the main part of the hull cleared the water with just a special fin submerged. I believe that he was doing about 15 knots. This was at Long Beach about 15 years ago.

Bob S.

Hi Bob,

Here are some references:







Those pedal boats look like fun.

Byron

[Bob S.]

Hi Bob,

Here are some references:







Those pedal boats look like fun.

Byron

Good job searching, Byron. I had forgotten the proper term for it: hydrofoil. I had also forgotten about that one propelled by bouncing up and down. There's lots of great stuff out there.

Bob S.

[mrpeepers]

58' ~3:00/500m, single scull

[Byron Drachman]

Couldn't resist sharing the joys of early morning sculling on a quiet river: A heron and a deer at sunrise

heron_and_deer_Aug_1_2012_c_r.jpg (41.7 KiB) Viewed 15810 times

[Byron Drachman]

I did a typical 16K this morning with a few "power 30's" tossed in before finishing. A friend is in the sunlight coming around the bend:

Deb_on_flat_water_Aug_17_2012_c_r.jpg (112.72 KiB) Viewed 15773 times

[mrpeepers]

45' at 141 bpm heart rate, 7082m. Beautiful weather.

[Rockin Roland]

Last Wednesday was one of those beautifull still and warm summer evenings. I was fortunate enough, due to my recent 6:29 erg time, to be picked to row in an eight with blokes about half my age. Due to the flat water it was decided to go for a rather long row. We headed out towards the mouth of the river into a wide open area that would normaly be too choppy for rowing boats. However, that evening it was possible to take advantage of the still conditions and row about 10 to 12 km continuosly, without stopping, with square blades as a whole eight together.

Now anyone who has rowed eights before knows how difficult technically it is to row any sort of distance, square blades as a whole eight. In this crew there were a lot of highly skilled oarsmen so getting perfect balance was no problem. Despite this, I was amazed at how long we could keep going without any oars touching the water in the recovery phase. It was by far the longest distance I had ever rowed square blades without oars touching the water. We passed a group of rowing clubs on the river bank and noticed eveyone was looking at us. I myself on many occasions have stopped to look, at well drilled eights rowing square blades together, in envy. But this time I was in the boat and took the whole experience in. It's one of those moments that I'll remember forever.

[Rockin Roland]

It's stil very warm here. Temperature has been consistantly around 32 C(90 F) for a number of weeks now and no respite in sight. No significant rain has fallen since August last year. However that translates to very stable water/current conditions on the river I row on. Hence whenever I go out in the single I can get a really good hold of the water at the catch and push the shell away strongly with the feet/legs. Getting some good numbers on the NK stroke coach monitor.

Last Saturday we had a win in our master eight at the Henley on the Yarra regatta. Everyone is rapt about that, in particular seeing your name go on a prestigious perpetual trophy. We still have a number of races coming up for the eight which is eating into the time I get to train in my single. Yesterday was my first chance in 10 days to train in my single. I find that it takes about 30 minutes of rowing to get back into the groove after long periods away from the single. It's probably more a mental/confidence thing though than anything else. All that sweep rowing has helped me stay in tune for sculling, together with some time on my dynamic erg.

After finding back my confidence in the single, I yesterday did 2 x 2000m pieces, flat out at race pace. Although I wasn't wearing a heart rate monitor to find my max, but due to ideal rowing conditions, I felt just as exhausted and legless when I got out of the boat afterwards as I would getting off an erg. It makes for a very satisfying workout, particularily knowing that I got max physical benefit(plus being rowing specific) without using an erg or other gym equipment.