Part - 3
Dear Friends
As previously indicated - in this 3rd-Part I will present and slightly discuss some sources and material that deserve to be more widely known.
A short litterature-list follows - these are all very highly recommended and will also be further commented.
1: "Wind fur Haus und Hof" - Uwe Hallenga - Germany 1990-99 - ISBN 3-922964-09-5
Cost: 7.60 Euros
2: "The Penryn Windmill Book" - Patrick Arnoldi - Canada 1995
Mail to: windmill@kawartha.com
3: "Einfalle statt Abfalle - Windkraft" [a series of 3 books] - Christian Kuhtz - Kiel Germany.
Cost for all three books: 11 Euros
4: "Handbuch Windenergie Technik" - Prof. Horst Crome - TU Bremen Germany 2000
ISBN 3-922964-78-8
Cost: 29.60 Euros
5: "Maine-built Windmill" - Everett Russell - Home Power Magazine USA # 79 Oct-Nov 2000 pages 46-50
http://www.homepower.com
Books nr. 1,3, and 4 can be obtained from the very good and helpful publishing company of http://www.oekobuch.de
These 3 books are more than extensively illustrated and so can be utilized even without an adequate working knowledge of German.
If you order "The Penryn Windmill Book" - request an unbound "loose-leaf" copy as the spiral-binding in some cases goes slightly too close to the text. In my case I have placed the pages of my copy into individual plastic A4-size envelopes.
Section A:
Uwe Hallenga presents a design for a 2-bladed wooden rotor 220 cms in diameter.
This design is also rather similar to a smaller version of the Danish CALORIUS water-heating 2-bladed wind turbine and this strong rotor design is very suitable for the laminated technology as described in the previous Part - 1. However it is likewise also necessary to carefully consider the measurements.
For my construction - I first glued together 5 strips of wood - 240 x 5 x 1.8 cms. Then on the two outer edges two further strips 240 x 5 x 3 cms were glued.
For this task it is advisable to request the assistance of friends - one to hold the strip, one to apply the construction glue and a third to spread the glue smoothly over the strip. One should not waste time during this process as the glue can risk premature setting.
Of course the work must be tightly clamped with heavy duty concrete formwork clamps overnight.
The full-size measurements were first drawn on - and then cut-out - on a full-size cardboard pattern that had been joined with tape. After a first light smoothing of both broad wooden surfaces the pattern was laid on top and the shape transferred. Thereafter the measurement were drawn up on all 4 sides of the plank.
This now very strong and robust rotor was then carved in the usual manner using both machine and hand tools.
Please note that the final illustration shows the possible application of glass-fibre if so desired.
Section B:
The book by Patrick Arnoldi belongs on the shelf of all wind experimenters - although perhaps there maybe some small errors the width and scope of this work is really unique and valuable.
Mr Arnoldi has devoted a considerable effort into ultra low-cost solutions. I include here a section of his proposal for a straight-sided 3-blade rotor element profile suitable for rotor diameters of up to 14 ft.
Section C:
It has previously been discussed on this board concerning the so-called difficulties of "start-up" when using the 2-bladed rotor design. I therefore include a design from Christian Kuhtz showing the construction and mounting of a "help or start-blade".
The 3 books from Christian Kuhtz - cover all aspects from re-winding to construction etc etc and are likewise highly recommended
Section D:
Unfortunately one of the best modern books suitable for the use by members of this board is only available in German - Prof Horst Crome's fully illustrated and highly detailed book concerns a step-by-step hands-on design and construction project made by him and his students at the Technical University in Bremen. My friends and I have often discussed the necessity of a translation of this book.
Prof Crome is infulenced by and further develops on the original Danish 40 kW grid-connected induction generator AGRICCO Wind turbines from 1919 [also produced under licence by KLOSTER in Holstein, N. Germany and by WERKSPOOR in The Netherlands - if any readers hear of any information concerning these - please contact the Danish wind historical museum - www.vindhistorie.dk]
Prof Crome has designed a series of 2-12 blades models from 1.5 - 20 kW. A new profile has been designed and is shown here. However the following profiles are similar and suitable:
Go449, GO624, GO623, GO508, GO711, Clark Y, NACA 4312, and NACA 6315
These blades are straight-sided as is also shown in the KLOSTER-AGRICCO-design illustration in Dip. Ing. Dr. Albert Betz's classic book "Wind-Energie" - Gottingen Germany from 1926 and in the following image from "Wie man Windrader baut" by Felix von Konig - 5th ed. Munich 1981 - 1SBN 3-7906-0110-1
Please note the typical welded hexagonal design of the center hub - a useful, reliable and entirely suitable technology dating from the late 18th century.
Finally - I close by referring all friends to check-out Everett Russells - 14 foot diameter 3-bladed design from "Home-Power" - as mentioned above. Please note the cut-out overspeed vane. I can additionally add that that there is considerable material on these overspeed vanes in the different German books mentioned above.
PS: I later will send in a further "Part" concerning horizontal rotors, super-fans and Cretan windmills. - And let's hope that the "illustrations succeed" although I have had to utilize another program to access this function.
With best wishes to all - JF
