Study for Increasing the Output Power of a Micro-Wind Generator ��

(1)

�

� ��

�

��^��

��

^��

��

^��

��

^��

��

^��

Study for Increasing the Output Power of a Micro-Wind Generator

Hideaki Toya Yuji Tsukizawa

Norimi Akashi Toshifumi Yuji

A wind power generator is one of the clean energy sources. Since the output power increases proportionally to the third power of the wind velocity, a diffuser-type wind turbine has been known to increase the output power. Then, a study for increasing the output power of a micro-wind generator was performed. It is shown that novel diffuser structure (a cylindrical shroud) that can provide wind energy to blades effectively. The shroud was designed on the basis of an electronic computer analysis as well as experiment. The generation test with a truck running at a speed of 40-60km/h proves that the generator with shroud can provide higher output power than that without shroud. Based on the analysis, another diffuser structure (a compound shroud) was designed to reduce cost to manufacture the cylindrical shroud. The generation test was done with a test machine and preliminary result was reported.

��: wind generator, diffuser-type wind turbine, shroud, blade

��20�30kW ��

�.��

��

��2�3kW ��

��

�� 10m/s ��

�� 1.5m ��

�� kW �� ^2��

��

��2�4m/s �� 15 ��^�� 16 ��

�� ANSYS ��

��

��3 ��

�� 5�10 ��

��

�� ANSYS ��

��

��^1��

�.� ��

��

�� Fig.1 ��

��

�� (��)

(2)

�

��

Fig.1.Diffuser envelope

Fig.2 Distribution of wind velocity and pressure in a diffuser envelope

��

��^��Fig.2

��

��^��

��

��3 ��

��

��Fig.3 ��

��Fig.4(a)�(b)��

��

Fig.3 Cross-sectional drawing of a wind generator with a cylindrical shroud

Fig.4(a) Experimental apparatus

Fig.4(b) Distribution in the connection box

(3)

��

�

��

�

��

�

��

�

��

�

��

�

��

�� ^�

�� ^��

��12V/25A��

��

��2��

��

�� Fig.5�

Fig.7 ��Fig.5 ��

��

�� 40km/h ��

��65km/h ��

��2W ��

�40km/h ��1W ��

��

��65km/h ��7W ��

��

Fig.7 Output ratio with shroud to without shroud and truck speed

Fig.6 ��.��

��

��1.4�2.4 ��Fig.7 ��

��.��50km/h ��

��

��65km/h ��3.5 ��Fig.7

��

Fig.5 Generator output and truck speed

��55km/h ��5 �

��.��Fig.5 ��55km/h ��

��

1W��

��

��(ANSYS)��

��FLOATRAN��

��^��

ANSYS ED � Release 7.0 ��

ANSYSVer.8.0 ��

��1000 ��

��ANSYS Ver.8.0 ��

��

�� 65km/h �

��7W ��

��3 ��Fig.3 ��

��

�� Fig.8 ��

��

��10m/s ��

Fig.6 Rotational-number ratio with shroud to without ��20�35��

(4)

��

Fig.10 Cross-sectional drawing of a wind generator with a inner-taper shroud

��

Fig.8 Maximum wind velocity and rate of the flat portion

��30��

��

��ANSYSED �Release 7.0 ��

��

�� Fig.9 ��

��

��Fig�10 ��

��

��Fig.9��ANSYS ED �Release 7.0 ��

��

�.��

��300��

��.��

��

�� ANSYS Ver.8.0 ��

Fig.11 ��

��

��Fig.12 �10m/s ��

��

� ��

��

Fig.9 Distribution of the wind velocity for a cylindrical Fig.11 Wind velocity profile of the inner-taper shroud shroud and for a inner-taper shroud shown in Fig.10

(5)

�

��

�

��

�

��

�

��

Fig.12 Distribution of the wind velocity in the inner-taper shroud shown in Fig.10

� ��

��

Fig.14 Wind velocity profile of the inner-taper shroud with a 90�inlet

��

��45�� 90�� 2 ��

ANSYS Ver.8.0 ��

��

��150mm��

� 4 ��

Fig.13~Fig.15 ��2 ��

��

��(��

��)��

��.��2 ��

� ��

��

Fig.15 Maximum wind velocity in the inner-taper shroud with inlet and inlet length

��

Fig.13 Wind velocity profile of the inner-taper shroud Fig.16 Output power and truck speed for the compound

with a 45�inlet shroud with a 90�inlet

(6)

�

�Fig.15 ��150mm ��

��216400mm ^��

45��

��150mm��300mm�

�90��

��

Fig.16 ��1000��

��

5 ��

��

��Fig.5��

��

��ANSYS Ver.8.0 ��

��Fig.8��Fig.15��

��1.4 ��

��

��3 ��

��ANSYS��

��

��15 ��

��17 ��

14,16�17 ��

��

�� ANSYS �

��

��15 ��16 ��

��

�)��

��pp.76-79�

2) ��

pp.77-78 (2004)�

3) ��15 ��

4) ��16 ��

5) ��

pp.154-165��

6) CADCAE ��ANSYS ��

��pp.154-165��

Study for Increasing the Output Power of a Micro-Wind Generator ��������������������� �

�

���������������������

����

����

����

����

Study for Increasing the Output Power of a Micro-Wind Generator

Norimi Akashi Toshifumi Yuji

Study for Increasing the Output Power of a Micro-Wind Generator ��

��

��

��

��

��