Blade or vane arrangement for a gas turbine engine

A blade or vane arrangement for a gas turbine engine, comprising:

• an array of aerofoils mounted to respective platforms about an axis and defining a passage through which a working gas flow passes, and
• a datum,
• wherein each aerofoil of the array of aerofoils comprises a radial span, a pressure side, a suction side, a leading edge region, and a leading edge foot extending from the leading edge region, the leading edge foot comprising a ridge line,
• wherein each platform defines a channel and a platform leading edge, the channel comprises a minimum radial height line, and the platform leading edge partly defines a secondary flow outlet through which a secondary flow passes,
• wherein the ridge line is aligned generally in a direction of the working gas flow and the minimum radial height line is aligned generally in the direction of the secondary flow, and
• wherein the minimum radial height line is at a radial height below the datum in the range 2.5% and 20% of the radial span at a maximum depth of the channel.

A blade or vane arrangement for a gas turbine engine, comprising:

• an array of aerofoils mounted to respective platforms about an axis and defining a passage through which a working gas flow passes, and
• a datum,
• wherein each aerofoil of the array of aerofoils comprises a radial span, a pressure side, a suction side, a leading edge region, and a leading edge foot extending from the leading edge region, the leading edge foot comprising a ridge line,
• wherein each platform defines a channel and a platform leading edge, the channel comprises a minimum radial height line, and the platform leading edge partly defines a secondary flow outlet through which a secondary flow passes,
• wherein the ridge line is aligned generally in a direction of the working gas flow and the minimum radial height line is aligned generally in the direction of the secondary flow, and
• wherein a deepest or radially innermost point of the minimum radial height line is between the leading edge region and a crown on the suction side.

A blade or vane arrangement for a gas turbine engine, comprising:

• an array of aerofoils mounted to respective platforms about an axis and defining a passage through which a working gas flow passes, and
• a datum,
• wherein each aerofoil of the array of aerofoils comprises a radial span, a pressure side, a suction side, a leading edge region, and a leading edge foot extending from the leading edge region, the leading edge foot comprising a ridge line,
• wherein each platform defines a channel and a platform leading edge, the channel comprises a minimum radial height line, and the platform leading edge partly defines a secondary flow outlet through which a secondary flow passes,
• wherein the ridge line is aligned generally in a direction of the working gas flow and the minimum radial height line is aligned generally in the direction of the secondary flow, and
• wherein the minimum radial height line is initially angled within 30 degrees of the axis.

A blade or vane arrangement for a gas turbine engine, comprising:

• an array of aerofoils mounted to respective platforms about an axis and defining a passage through which a working gas flow passes, and
• a datum,
• wherein each aerofoil of the array of aerofoils comprises a radial span, a pressure side, a suction side, a leading edge region, and a leading edge foot extending from the leading edge region, the leading edge foot comprising a ridge line,
• wherein each platform defines a channel and a platform leading edge, the channel comprises a minimum radial height line, and the platform leading edge partly defines a secondary flow outlet through which a secondary flow passes,
• wherein the ridge line is aligned generally in a direction of the working gas flow and the minimum radial height line is aligned generally in the direction of the secondary flow, and
• wherein the leading edge foot blends out a distance between and including 50% and 100% of an aerofoil chord length from the leading edge region on the pressure side.

A blade or vane arrangement for a gas turbine engine, comprising:

• an array of aerofoils mounted to respective platforms about an axis and defining a passage through which a working gas flow passes, and
• a datum,
• wherein each aerofoil of the array of aerofoils comprises a radial span, a pressure side, a suction side, a leading edge region, and a leading edge foot extending from the leading edge region, the leading edge foot comprising a ridge line,
• wherein each platform defines a channel and a platform leading edge, the channel comprises a minimum radial height line, and the platform leading edge partly defines a secondary flow outlet through which a secondary flow passes,
• wherein the ridge line is aligned generally in a direction of the working gas flow and the minimum radial height line is aligned generally in the direction of the secondary flow, and
• wherein the leading edge foot blends out between and including a suction side crown and a throat plane on the suction side.