| 主权项 |
1. A blade row group arrangeable in a main flow path of a fluid-flow machine and including N adjacent member blade rows firmly arranged relative to one another in both the meridional direction (m) and the circumferential direction (u), with the number N of the member blade rows being greater than/equal to 2 and (i) designating the running index with values between 1 and N, with a front member blade row with front blades (i) having a leading edge VK(i) and a trailing edge HK(i) as well as a rear member blade row with rear blades (i+1) having a leading edge VK(i+1) and a trailing edge HK(i+1) being provided,
where the blade row group has two main flow path boundaries (HB), where the leading edge VK(i+1) of at least one blade (i+1) of the rear member blade row is provided in the vicinity of a blade (i) of the front member blade row (i), where the edges of the blades (i, i+1) of the blade row groups are viewed between a main flow path boundary (HB) and a mean meridional flow line (SLM) in the main flow path center, where, when viewing the blade row group in a plane established by the meridional direction (m) and by the circumferential coordinate (u) (meridional flow line section), the chord Se(i) of the front blade is defined as the tangent lying on the profile of the front blade (i) on the pressure side and the chord Se(i+1) of the rear blade is defined as the tangent lying on the profile of the rear blade (i+1) on the pressure side, where the stagger angle of the front blade lambda(i) and the stagger angle of the rear blade lambda(i+1) are defined as angles of inclination of the respective chord relative to the meridional direction (m), where the mean stagger angle lambdam is defined as the mean value of the stagger angles lambda(i) and lambda(i+1), in accordance with lambdam=(lambda(i)+lambda(i+1))/2, where an auxiliary coordinate system having a first, a second and a third coordinate direction (s, q, or) is provided, with the first coordinate direction (s) facing downstream at the angle lambdam relative to the meridional direction (m), the second coordinate direction (q), perpendicular to the first coordinate direction (s), facing away from the pressure side of the front blade (i), and the third coordinate direction (or) being perpendicular to the first coordinate direction (s) and to the second coordinate direction (q), where the degree of bulge WG of a blade edge is defined as the greatest ascertainable distance (d) between the respective blade edge itself and the straight connection of the blade edge points on the mean meridional flow line (SLM) and the main flow path boundary (HB) relative to the width dor measured perpendicular to the first coordinate direction (s) at the blade edge between the mean meridional flow line (SLM) and the main flow path boundary (HB), in accordance with WG=d/dor, and wherein the area between the mean meridional flow line (SLM) and one of the main flow path boundaries (HB) in a view perpendicular to the third coordinate direction (or) and within an angular range of +/−45° about the first coordinate direction (s) the blade leading edge VK(i) of the front blade (i) and both blade edges VK(i+1) and HK(i+1) of the rear blade (i+1) are arranged at least in a partial area between the mean meridional flow line (SLM) and the main flow path boundary (HB) on the pressure side of the blade trailing edge HK(i) of the front blade (i). |
