KD 285 reviewed

A new Cmh0.225-alpha curve has been added to figure 9 of KD 285 about the Gö 711 airfoil. This curve has an almost constant value of Cmh = -0.13 for values of alpha in between -4° and 13°.

Notitie over 4-bladige windturbine gewijzigd

Hoofdstuk 2 van de notitie: “Ideeën over een 4-bladige windturbine met een rotordiameter van 30 m” werd gewijzigd”. Er werd een stukje toegevoegd over de tandwielkast en de maximale tipsnelheid werd berekend op 156 km/uur. Dit is een factor 0,451 lager dan die van de gebruikelijke grote windturbines en daardoor zal de rotor veel minder geluid maken en zullen er veel minder vogelslachtoffers vallen.

KD 745 reviewed

Report KD 745 about the Sparta Ion front wheel hub motor has been reviewed. Chapter 6 has been modified completely. The 3-bladed VIRYA-1.25B3 rotor has been replaced by the 3-bladed VIRYA-1.38 rotor because the starting wind speed of the VIRYA-1.25B3 rotor was too high. The 3-bladed VIRYA-1.38 rotor has about the same P-n curves as the 4-bladed VIRYA-1.4 rotor as described in chapter 5 but uses less material.

KD 727 reviewed

A new chapter 11 has been added to report KD 727 about the VIRYA-12. The title of this chapter is: “Use of a PM-generator of Hefei Top Grand type PMG900-I-30KW-100R”. The same generator is also used in the VIRYA-14 as described in report KD 732.

KD 750 Added

Report KD 750 has been added at the menu KD-reports. The title of this report is: “Calculations executed for the rotor of the VIRYA-5R windmill (lamda design = 6.5, Gö 711 airfoil) with a 2-bladed rotor made out of Roofmate, glass fibre and epoxy”. This is an alternative rotor if good quality wood which is needed for the 2-bladed rotor of the VIRYA-5 or the 3-bladed rotor of the VIRYA-5B3 isn’t available.

KD 670 removed

Report KD 670 about the VIRYA-5.2 has been removed. It appeared that the used generator of Hefei Top Grand type TGET450-2KW-180R is too light. The about similar VIRYA-5B3 is described in report KD 710 and this wind turbine uses the stronger generator TGET450-5KW-300R.

KD 579 reviewed

Chapter 6.5 of report KD 579 about the VIRYA-6.5 has been reviewed completely. The title of this chapter is now: “Use of the VIRYA-6.5 with a PM-generator type PMG-I-620-10kW-250R”. This axial flux PM-generator is made by the Chinese manufacturer Hefei Top Grand.

KD 484 reviewed

A new chapter 9 has been added to report KD 484 about the VIRYA-3B3 rotor. The title of this chapter is: “Use of a cheaper alternative PM-generator”. This generator is described in chapter 7 of report KD 718.

KD 745 reviewed

A new chapter 5 has been added to report KD 745 about the Sparta Ion hub motor. The title of this new chapter is: “Designing a small rotor with a high starting torque coefficient”. The rotor is called the VIRYA-1.4. It has a diameter of 1.4 m, four steel blades and a design tip speed ratio of 2.5.