William James and Essays on Pragmatism

[IntegEner]

Diaries are just thinking to oneself and so I start here with "Dear Diary". The philosopher William James (1842 - 1910) touched the soul of the New World with his insistence on the need for making sense of everyday life - something he called Pragmatism. Here is a quote from the book:

"When .... was a child it is written that he had a mania for having everything explained to him, and that when people put him off with vague verbal accounts of any phenomenon he would interrupt them impatiently by saying, 'Yes, but I want you to tell me the particular go of it!' Had his question been about truth, only a pragmatist could have told him the particular go of it....... But the .... view of truth has been so ferociously attacked by rationalistic philosophers and so abominably misunderstood that here, if anywhere, is the point where a clear and simple statement should be made."

Within the context of wind energy I have come to agree wholeheartedly with this philosophy. What seems to be happening is that the same half measures and wasteful practices that have come to typify much of the energy industry are finding their way into some of these renewables like this one. Treating the air mass of the wind as an object that must satisfy the laws of conservation, not to mention Newton's Law, is not being given the attention it rightly must be given for a correct interpretation, the only possible deductive "particular go", of the processes it undergoes.

Deductive logic has always been used instinctively for ordinary push and pull problems with discrete objects. We start with F = ma. But somehow in aerodynamics this is not allowed. We must forever be stuck in a rut trying to rediscover Newton's Law the same way that Newton did, inductively. It certainly is safe and secure to go to a graph or table that has been obtained from hard data in the field or wind tunnels and verified over the years many times, resulting in various nondimensional parameters called coefficients that can be stretched to cover the scaling to other cases. It is as if Newton's Law has been forever ruled out as being not good enough per se. Though it answers the question of "why" and provides a feeling of complete understanding of the processes, the "particular go" of things, this is forbidden here in the realm of the sacrosanct "miracle of flight".

This is an old story and, thereby, not a rant. I have no complaints. Everyone is free to use the NACA profile graphs and talk about lift and drag coefficients all everyone pleases. But it must be said here that I hold in my heart a complete understanding of how the wind drives the blades and can write down in simple, terse equations on a piece of paper how the various parameters involved interact with each other. Let no one claim I am doing something wrong. What's more, others have been pursuing this approach independently as well.

The central vehicle for the conversion of the wind's kinetic energy to the torque and motion of the wind turbine blade moving faster than the wind is airflow deflection. When the airflow is deflected it both continues on at the same velocity and also undergoes a substantial reduction in velocity at the same time depending on the blade design and the frame of reference within which it is viewed. The result is that something happens and that "something" means that the blade segment has a conversion efficiency that can be clearly understood in general terms for all the blade segments of the blade and over all variations of blades and wind turbine configurations everywhere.

It bears repeating that our wind turbines as presently designed within the current state of the technology do not convert as much of the wind's energy as is ordinarily assumed. In checking the power production curves of all sizes and shapes of these devices and from all manufacturers everywhere one can verify this for oneself. The industry is burdened with many caveats - don't do this, don't do that. The tool that is lacking for better insights in how best to proceed might just possibly be nothing more consequential or out-of-the-ordinary than a few of the mechanical laws of physics.

More if time allows.

Anthony "nickname omitted" Chessick

IntegEner-W

Tehachapi, CA

www.integener.com

[monte350c]

I am curious!

Will you be developing some machines based on the new theory? It would be interesting to compare a machine based on the new theory, with an example machine based on the existing aerodynamic theories...

Some machines do quite well actually.

Have a look at www.enercon.de and look at the data sheet for their E70 model.

At 9 m/s and a swept area of 3,959 square meters, their output is 892 kw.

In standard numbers, 20.1 mph, 42,614.3 square feet.

So...

20. 1^3 x 42,614.3 x .00503 = 1,740.65 total kw available in that swept area according to the Betz theory.
    
892. /1,740.65 = 51% efficient.
     
     

That's overall including blade and alternator losses.

Comments?

Ted.

[Victor]

Hi Ted,

 The 1740.65 kw would be the total energy in the wind with a maximum of  1032.2 kw obtainable due to Betz  892 /1032= 86% efficient. Very good indeed.

Victor

[monte350c]

Thanks Victor!

Typing faster than thinking!

Makes their number look even more impressive.

It would be neat if we could find ways to make the small machines closer to this kind of efficiency. On the one hand a lot of people I talk to have the attitude that since the power input (wind) is free what does it matter...

But it does matter - if you can get closer to this kind of efficiency then the cost for each watt collected should go down, provided the price of the efficiency isn't too high.

Let's see:

On a 10' machine, also at 20 mph...

 20^3 x 78.5 x .00503 x .59 = 1,863

 1,863 x .86 = 1,602

Wouldn't THAT be nice!

Ted.

[IntegEner]

Thanks for taking the time to run those numbers by. I do it like this for the same example:

((9/13.41)^3 x 3959) / 1.14 = 1049.6 kw. and 892 / 1049.6 = about the same 85%.

This, though, is applicable to "near-perfect conditions". Anything less or more than 9 meters/second and it falls off. Remember that I said "at rated power". On the ridges here in Tehachapi the winds go from nothing to 20 meters/second in no time at all and in remembering all of this, take a look at perhaps an older (possibly out-of-date) production curve of the 1.5 MW sl from the GE website (with my own notations including the Betz energy curve added):





Meanwhile one BTU - the heat equivalent of burning one match stick - is 778 foot pounds or raising 778 pounds off the floor one foot. One pound of lignite (low BTU) coal has about 7000 BTUs in it. One pound. Thermodynamic efficiencies are only about 30% for burning coal as such but even the air in just a cubic yard of volume has a mass weight of two pounds.

It is in the big picture where efficiency differences become important. Back in the Minnesota farm country where land goes by square mile sections, visualizing the wind at 30 mph entering one side of such an area up to an elevation of 1000 feet results in a Betz-adjusted total energy potential of 429.9 MWs. Remember that the air enclosed in a square mile of surface area up to this elevation has a mass of over one million tons, about the same as the displacement weight of all ten of the U.S. Navy's mighty nuclear powered aircraft carriers (one more is being built). One square mile.

Even just this 100% - 85% = 15% energy inefficiency deficit applied to 429.9 MWs is 64.5 MWs. How many 1.5 MW turbines is this again on just one square mile? I am using the optimum performance criterion established above for the Enercon.

The other part of the problem is where does the energy in this energy deficit of 15% go? Likely most of it currently goes into the parasitic drag of the blades and creating the "whoosh" sound from them. What isn't no doubt escapes downwind due to a missing blade or two that would be there if it weren't for the parasitic drag thereby added.

It is easy to go on like this and I am sure not very welcome, even a little off-topic. At this time of the close of the year before the start of the next, it might be appropriate to reflect on these thoughts. Wind energy has embraced many euphemisms about how well it is doing - the number of homes serviced, etc. - but knuckling down to some of the hard facts of the details of blade performance over hard won land areas available to it also needs to be considered.

Anthony "Knuckling down Knucks" Chessick

Integener-W

Tehachapi, CA

www.integener.com

[IntegEner]

The fun of this little branching off from the rest of wind energy is that it is something that is making tracks. The "new" in "Newtonian" is apt. The physical limitations of wind energy devices are, to be honest, more about the blades than they are about the rest of them since, once working, attention always focuses on the rotors as a way of gaining more performance. Usually it is then too late to do anything about them. I always liked the PVC pipe blades and other blades of this general design but how is it possible to make these blades longer than just a foot or two and yet capable of standing up to strong winds? Answers to this are scarce.

Here is the "Bent Air Law" of wind energy aerodynamics:

Makes a nice T-shirt iron on transfer. Better, perhaps?, than "I'm with STUPID" or even images of rock stars. Pretty girls would be quite curious as to what the heck this is all about and the times are favoring interest in energy. This formula is readily derivable from Newtonian principles and the best thing about it is that it still needs more of everyone's input. The constant "C" needs to be found for different blade designs and it also needs to be extended to the entire lengths of blades by means of digital software. As it stands it is general in scope for every blade segment everywhere.

The apparent wind vector, A, like the wind seen by the sails of a sailboat, is deflected to point back in the direction of the trailing edge. In going around this corner the wind remains at the same velocity but creates a force on the blade, a part of which, F, points in the forward direction as shown. The blade and the sailboat are moving. When the wind velocity is viewed from the standing-still position in the air or water, the wind velocity is seen to be having been reduced, not to zero, but reduced to a smaller value. No drag of any kind or vortex generators or anything else are needed. The wind is slowed and, as it is slowed, it gives up a part of its kinetic energy to the blade or sail, propelling them forward even if they are moving faster than the wind.

More detailed talk about how this works can be found on the www.integener.com website in the chapters on the home page and in the booklet mentioned, available for free as a special deal if anyone seeing this so requests a copy! A contribution of 99 cents for using PayPal as a help for doing this and for the mailing costs is welcomed. If anyone wants to help in making up the T-shirt transfers, that is welcomed also.

Anthony "Knucks" Chessick

IntegEner-W

www.integener.com

[finnsawyer]

The wind blows high;

The wind blows low;

It changes direction, you know;

But when it does work it goes a little more slow

Now, I'm a poet!

[IntegEner]

This follows up what was said earlier in my posts above on the "Bent Air Law" about the wind flow having been reduced in velocity after deflection by the blade.

Naturally the question is "what is the new, lower velocity?" The answer is that the wind velocity after deflection by the blade is reduced to a value equal to the apparent wind velocity approaching the leading edge of the blade minus the velocity of the blade moving forward as shown in the graphic, i.e. (A - V). For a blade velocity, V, of zero, i.e. when the rotor is not moving, this reduces to the original wind flow velocity, W, but the wind has turned a corner to flow at right angles to move parallel to the trailing edge. In this case plenty of force is seen by the blade from the wind turning this corner but the wind's kinetic energy remains intact and no energy is converted nor is any work done on the blade.

When the blade is moving at a high speed this vector difference between the apparent airflow velocity, A, and the blade velocity, V, diminishes and so the resulting velocity after deflection is reduced to a low value. It is never equal to zero but can become quite close to it and in such cases for all practical purposes the kinetic energy of the wind is almost all transferred to the blade.

The strangeness of all this and being able to say with such assurance that the airflow is this or that comes about because it is based on physical laws that relate to it, in this case, Newton's Law. Why must the world continue to be left in a mind haze about how aerodynamic forces are generated when deductive reasoning such as this from known science can be so readily made available?

Anthony Chessick

IntegEner-W

www.integener.com

[finnsawyer]

So, you're coming around.  No one is saying you can't use Newtonian Mechanics.  But if you do, you need to make an honest effort, and that includes using Newton's Calculus.  As you like to point out, the velocity of a mass is a vector quantity.  The time rate of change of the velocity is the acceleration and is itself a vector quantity.  This is the acceleration you need in your force equation.  The acceleration vector can point in any direction in space depending on the forces involved.  As such, it can be resolved in a component at right angles to the velocity vector and a component parallel to the velocity vector.  The component at right angles to the velocity does not change the magnitude of the velocity.  If that were the only component of the acceleration it would mean the energy of the mass would not change (0.5xMxV^2 doesn't change; V is the magnitude of the velocity vector).  Only the direction of the velocity vector would change.  The component of acceleration parallel to the velocity vector causes the mass to either speed up or slow down and is what allows energy to be added to or extracted from the mass.  In the case of an air flow which is distributed in space you need to break the air flow into small units of mass and consider how each one contributes to the overall effect.  You need to integrate all these little effects over the entire air mass.  You have a great deal of work to do.

As far as your "bent air" equation is concerned, your coefficient C is conceptually the same as the lift coefficient Cl, as it must be determined for each air foil.  The equation itself describes the "average" behavior of the airfoil, and you hope C will prove to be a constant over some useful range of angles just as Cl is.  In fact, this is beginning to look more and more like the lift equation rehashed.  I wouldn't be surprised if your C was related to Cl by a constant multiplier.  Deductive reasoning?  When it leads right back to where we already are?

In the real world an integral part of the behavior of air foils involves drag.  You don't consider it.  Not doing so means any results you obtain will overstate the efficiency of the systems.

[finnsawyer]

I took another look at his equation.  His force is not the lift force but is shown opposite to the drag force.  So, C is related to the drag coefficient Cd?  Well, not quite.  Drag is pretty much constant over a small range of the angle he calls alpha.  The problem is that 1 - cos(alpha) goes as (alpha)^2 for small values of alpha.  In other words his force goes to zero dead on, which is is not supported by physical evidence.  It's time to put this "theory" in the garbage bin where it belongs.

[IntegEner]

This belated reply to the question of "showing something that works" is probably going to meet further skepticism. Suffice it to say that I am convinced of the need for a better understanding of how wind turbine blades interact with the wind and that is all that matters to me. I write my words slowly and they are invariably read quickly, requiring much patience on my part, surely something needing tolerance in return. Here is a closer view of the same wind rotator shown on my website:





The blades here are seen as twisted due to their speed of rotation and are nothing but insubstantial sheet metal, doubled and offset so as to assist the Coanda Effect in gaining additional airflow deflection, with a long, flat trailing edge pitched to zero, even slightly negative. No one has been able yet to tell me what NACA profile this is nor why it isn't susceptible to stalling.

There is always the 30 page booklet on the Lift Principle mentioned on my website, offered specially right here and right now for free upon sending an e-mail message with an address for the mailing of it, even outside the States. (The address information is deleted from our files upon completion of the shipment.) It is a good start in seeing the Newtonian Principle as described in some detail and really quite worth while. No need to click on the PayPal button but send off your message soon.

See comments made elsewhere on this thread and also on the recent "How to avoid stalling" thread for more detail. It is not so difficult to understand that it is airflow deflection and only airflow deflection that creates a driving force on a blade moving faster than the wind and made amenable to calculation with straightforward equations such as the Bent Air Law (as is described in some detail in the booklet mentioned above).

Does anyone need to see how I clamp the aluminum sheet metal pieces from the 4 inch (100 mm.) wide rolls of roof flashing in the hardware store to a counter edge corner and back it with a 5/16" diameter wooden dowel in order to start the bending of the leading edge? It isn't fair (and often quite persnickety) to tell me that I am doing something wrong when what I am doing works so well!

Thin blades for lift-based rotors rule!

Anthony C.

IntegEner-W

www.integener.com

[TomW]

Anthony;

I do like the look of those.

However;

I made some PVC blades that spun like crazy in the slightest breeze, very fast and smooth. Right up until you attempted to extract any power.

I see you only have these on a "bearing". Have you tried pulling any power from them yet?

Cheers.

TomW

[IntegEner]

The purpose of this work is to apply for a state grant from the energy commission and no one seems to want to commit themselves quite yet to calling this is a bummer. It is easier to put a generator on a verticals device and so this has been done (see below). The blades are of the same ultra-thin, sail-like, doubled, and offset design. The one has been used to reconfigure the other with good results for both. I pursue this with great vigor. For 10 mph winds and above (measured with a Kestrel 2000 hand held wind meter) the three phase 3.5" diameter axial flux generator mounted on it just below the platform lights the LED lights. It also has enough power and startup torque for me to consider connecting instead a small 6 watt bicycle generator that I have to the shaft without mechanical advantage.

Within the context of 3 foot diameter blades near ground level the above horizontals rotor certainly outperforms the well known 22" diameter decorative old time farm windmill rotors we often see here in the yards of homes with their 12 blades.





I think all this speaks for itself, something that satisfies small needs for power that people find easy and inexpensive to buy.

Anthony C.

IntegEner-W

www.integener.com

[IntegEner]

IntegEner-Wind has long had a booklet advertised on the website that details how the lift principle works using Newtonian Mechanics in aerodynamics work, for wind turbines as well as for the case of aircraft, in clear terms without some of the earlier unsatisfactory theories that have typified this subject - in the opinion of such agencies as, for example, NASA (see their website) and to which we feel some more attention is needed. It has certainly survived exposure to the Internet the last few years and discussions here on OtherPower.com have covered some of the material contained therein with general approval from those who have seen them. It seems pointless to repeat some of this detail here, again and again, and so it is being offered for free, mailing costs defrayed as well, bypassing the usual PayPal buttons normally used for purposes of ordering it. I honestly believe it is a clearer explanation than most on this subject.

An e-message would be necessary to be sent to IntegEner-W at mail@integener.com with a name and mailing address, which are to be deleted from our files upon completion of the order. We have now already a backlog of orders from wind energy observers and enthusiasts from a similar mention of this offer elsewhere. Multiple copies, within reason, may also be requested. More information about the booklet is available on the website - www.integener.com. Here are the colorful covers of the booklet:





Anthony C.

IntegEner-W

Tehachapi, CA

www.integener.com