Patent ID: 8678760

Claim:
A bypass duct of a turbofan engine comprising: downstream guide vanes of a downstream guide vane assembly arranged in the bypass duct for de-swirling an airflow produced by a fan of the turbofan engine; at least one fairing element arranged behind and downstream of at least one of the downstream guide vanes containing installations provided in the bypass duct, wherein the at least one of the downstream guide vanes and the at least one fairing element is provided as a combined, one-piece vane and fairing element; wherein the combined vane and fairing element provides for de-swirling and low-loss outflow of the airflow in a given pressure and suction-side outer contour according to a course of a skeleton line angle α of a profile determined by a respective chord length A of a respective downstream guide vane and a total length L of the combined vane and fairing element; wherein the total length L of the combined vane and fairing element between a leading edge VK and a trailing edge HK thereof is divided into a first section A corresponding to the chord length A of the respective downstream guide vane, a second section B having a length that essentially conforms to the length of the first section A, a third section C whose length is approx. 0.7(L−2A), and a fourth section D whose length is approx 0.3(L−2A), with the skeleton line angle α increasing to a value of 80%+10% by the end of the first section A, initially further increasing and finally having a maximum value of 105%+5% in the second section B, gradually decreasing to 100% in the third section C, and remaining constant at 100% in the fourth section D.