Methods and apparatus for reducing vibrations induced to airfoils

An airfoil for a gas turbine engine, said airfoil comprising a radial span dependent chord length C, a respective maximum thickness T, and a maximum thickness to chord length ratio (Tmax/C ratio), said airfoil further comprising:

• a first sidewall;
• a second sidewall coupled to said first sidewall at a leading edge and at a trailing edge, said trailing edge tapered such that a thickness of said trailing edge increases from about zero percent span to about seventy percent span;
• a root portion comprising a first Tmax/C ratio;
• a tip portion comprising a second Tmax/C ratio;
• and
• a mid portion extending between said root portion and said tip portion, said mid portion comprising a third Tmax/C ratio that is less than the first Tmax/C ratio and the second Tmax/C ratio.

A gas turbine engine comprising a plurality of rotor blades, each said rotor blade comprising an airfoil comprising a radial span dependent chord length C, a respective maximum thickness T, and a maximum thickness to chord length ratio (Tmax/C ratio), said airfoil comprising:

• a first sidewall;
• a second sidewall coupled to said first sidewall at a leading edge and at a trailing edge, said trailing edge comprises a first thickness at about zero percent span, a second thickness at about one hundred percent of span, and a maximum thickness at about seventy percent of span;
• a root portion at a zero percent radial span having a first Tmax/C ratio;
• a tip portion at a one hundred percent radial span having a second Tmax/C ratio;
• and
• a mid portion extending between said root portion and said tip portion having a third Tmax/C ratio, the third Tmax/C ratio that is less than the first Tmax/C ratio and the second Tmax/C ratio.

An airfoil for a gas turbine engine, said airfoil comprising:

• a first sidewall extending between a root portion and a tip portion;
• and
• a second sidewall extending between said root portion and said tip portion, said second sidewall coupled to said first sidewall at a leading edge and at a trailing edge;
• said airfoil comprising a maximum thickness, a leading edge thickness, a midchord thickness, and a trailing edge thickness wherein said trailing edge thickness is greater than said leading edge thickness, wherein each of said thicknesses is measured between said first and said second sidewalls.