| 摘要 |
One embodiment of a rotor blade (102) for a vertical axis wind turbine (100) comprises a central portion (130) having a central axis (132) and at least two blade members (114, 116). The blade members each have a proximal end (126) attached to the central portion, a high drag side (118) and a low drag side (120) that is opposite the high drag side. Each of the blade members also includes an uncovered vent (140) comprising an opening (142) through the blade member that provides an unobstructed path for airflow through the blade member. In one embodiment, a pair of fins (162, 164) are positioned adjacent the opening of the vent and extend from the high drag side of the blade member. Another embodiment of a rotor blade (102) for a vertical axis wind turbine (100) comprises a central portion (130) having a central axis (132), first and second blade members (114, 116) attached to the central portion and top and bottom blade caps (190, 192). The first and second blade members each comprise a distal edge (204), which is radially displaced from the central axis, a top edge (194), a bottom edge (196) displaced from the top edge along the central axis, a high drag side (118) and a low drag side (220) that is opposite the high drag side. The top and bottom blade caps are respectively attached to the top and bottom edges of the first blade member. Each blade cap comprises first and second portions (200, 206). The first portion extends from the first blade member to a blade line (202), which extends radially from the central axis to the distal edge of the first blade member. The second portion extends from the first portion at the blade line and has a trailing edge (208) that is angularly displaced about the central axis from the blade line and the second blade member. In one embodiment, a pair of second blade cap sections are attached to the top and bottom edges of the second blade member and each include first and second portions. The first portion of the second blade cap sections (190, 192) extends from the second blade member to a second blade line (202), which extends radially from the central axis to the distal edge of the second blade member. The second portion of the second blade cap sections extends from the first portion at the second blade line, the second portion having a trailing edge (208) that is angularly displaced about the central axis from the second blade line and the first blade member. |
