What Is Aircraft Design Software?

The main links of the overall layout of the aircraft (aerodynamic layout, preliminary layout of internal loading, preliminary layout of key load-bearing structures, estimation of radar scattering RCS values, and initial estimation of the center of gravity of the aircraft, etc.) were finally analyzed and calculated, and finally identified The main geometric parameters of the aircraft shape (a preliminary sketch of the three sides of the aircraft) and the overall dimensions of each part of the aircraft, and the overall process given in the form of an aircraft shape theory diagram, is the overall aircraft shape design.

For a long time, the loft in ship design and the drawing of die lines in aircraft design have been classified as aircraft shape designs. This is because in the past, the method of extracting shapes was basically adopted by surveying and mapping. With the development of electronic computer technology, there have been methods that use graphic methods to mathematically approach and draw, and use computer programs and data to describe the shape of aircraft. People often refer to this process as computer-aided design (

General principles of shape design

We expect to find a design method that can quickly generate the shape, that is, analyze and evaluate according to tactical and technical requirements, give a preliminary overall layout, and use statistical methods and approximate calculations to initially determine the main geometric parameters of the aircraft. With these parameters, the first design drawing of the aircraft can be obtained by approximate calculation method or statistical method. The approximate weight estimation method and the calculation of radar scattering slag are used to give the total aircraft weight estimation value and the center of gravity. Limit position and RCS value.

Major issues to be addressed in aircraft component design

(1) Select the best values of main parameters and geometric dimensions;

(2) Select the best shape and construct the best shape;

(3) Select the best structural force type of aircraft components;

(4) Select the best materials and processes, the purpose is to meet the requirements of aeroelasticity, heat resistance, static strength, dynamic strength and fatigue strength, and to minimize the production cost of the aircraft under the conditions of ensuring the shape and surface quality in batch production, The aircraft is the lightest;

(5) Ensure the convenient use and maintenance of aircraft components. ^[1]

(1) Shape design of the cross section of the fuselage

The circular cross section of the fuselage is the most advantageous, it can ensure the smallest perimeter when the cross-sectional area is constant; or the surface area is the smallest when the volume is constant, so the friction is minimal.

(2) Exterior design of cockpit

Starting from the driver's vision requirements, the side view of the modern aircraft fuselage has a special profile. The lower part of the nose extends forward, from the pilot's eyes forward and downward through the lower boundary of the windshield to form a straight line, which can be arranged under this straight line. The shape of the machine head must not affect the field of vision. This approach is beneficial both in terms of aerodynamics and layout.

(3) Configuration design of wings and cockpit

The layout of supersonic fighter wings on the fuselage is generally as follows:

From the perspective of the wing and fuselage interference resistance, the medium and single wing is better. Early supersonic fighters focused on reducing drag during high-speed flight, and mostly used medium and single wings;

Considering the structure of the aircraft: The above single wing is the best;

From the take-off and landing performance requirements of the aircraft, in order to enhance ground performance and improve take-off and landing performance, the lower single-wing layout is generally used.

The cockpit of a supersonic fighter is generally arranged in a relatively forward position of the fuselage, in order to minimize its protruding resistance effect, and make the position of the air inlet as far as possible to compensate the rear of the cockpit. The cross-sectional area of the fuselage caused a sudden change in the cross-sectional area of the fuselage. ^[1]