1.

Fig. 1 It can be seen from the graph 1. that the most advantageous angle of attack of an airplane is greater than the most advantageous angle of attack of the wing by (2º÷3º).

2. I. Introduction

The aim of my research is Determining the coefficient of profile-wave resistance for the four profiles which shown with relative thickness ??? =5% , With the number M?=2.5. Construct the pressure distribution diagram for each profile at angles of attack ?? = 0,?5º,+5º. The coefficient of profile-wave resistance:

? ? = ? 2 ? ? ?? ?? ? 2 ? 1 = ? 2 ? (?0.0499584) ?2.5 2 ? 1 = 0.0436 Area BD ? ?? = ? + ? 2 = 0 + ? ?? = ?? ?? = 0.049958 rad=2.862405°=2°51 ? 45 ?? ? ? = ? 2 ? ? ?? ?? ? 2 ? 1 = ? 2 ? 0.0499584 ?2.5 2 ? 1 = ?0.0436 Area AC ? ?? = ?? ?? = ?0.04996 rad= ? 2.86241°= ? 2°51 ? 45 ?? ? ? = ? 2 ? ? ?? ?? ? 2 ? 1 = ? 2 ? (?0.0499584) ?2.5 2 ? 1 = 0.0436 Area CD ? ?? = ?? ?? = 0.049958 rad=2.862405°=2°51 ? 45 ?? ? ? = ? 2 ? ? ?? ?? ? 2 ? 1 = ? 2 ? (0.0499584) ?2.? ? = ? 2 ? ? ?? ?? ? 2 ? 1 = ? 2 ? (?0.13722486) ?2..71059°=?0°42 ? 38 ?? 2 ? ? ?? 2 ? (?0.01240219) ? = ? = ? = 0.0108 ? ?? ? 2 ? 1 ? 2.5 2 ? 1 Area AC ? ?? = ?? = ?0.08727 ???= ? 5°? ? = ? 2 ? ? ?? ?? ? 2 ? 1 = ? 2 ? (?0.08726646) ?2.5 2 ? 1 = 0.0762 Area BC ? ?? = ? + ? = 0.08726646 + 0.09966865 = 0.186935 rad=10.71059°=10°42 ? 38 ?? ? ? = ? 2 ? ? ?? ?? ? 2 ? 1 = ? 2 ? (0.18693511) ?2.5 2 ? 1 = ?0.1632 ?ð??" ( ? 2 ) =5? ? = 4 ? ? 2 ?? ? 2 ? 1 + ? 1 ? ?? 2 ?? ? 2 ? 1

Parameter K1 depends on the shape of the profile:

? 1 = 2 ? [( ?? u ? ??? ) 2 + ( ?? L ? ??? ) 2 ] ??? 1 0 ?? U ? ??? = 1 ?? ? ?? U ?? ?? ?? ? ??ð??"??L L U ? ?? ?? = 2 ???? U ???? = ?? 2 , ???? U ??? ????? = 1 ? ?????? ????? ???????????????? ???? ???? U ???? = ? ?? 2 , ???? U ??? ????? = ?1 ? ?????? ????? ???????????????? ???? ???? L ???? = ? ?? 2 , ???? L ??? ????? = ?1 ? ?????? ????? ???????????????? ???? ???? L ???? = ?? 2 , ???? L ??? ????? = 1 ? ?????? ????? ???????????????? ???? Year

Then the parameter K1 for profile 1 will be equal to

? 1 = 2 ? (1 2 ? 0.5 + (?1) 2 ? 0.5 + (?1) 2 ? 0.5 + 1 2 ? 0.5) = 2 ? 2 = 4

Defining the value of the parameter K1 for profile 2:

Defining the value of the parameter K1 for profile 4:

The Then the parameter K1 for profile 3 will be equal to

?? 1 = 2 ? ((0.5) 2 ? 1 + (?0.5) 2 ? 1) = 2 ? 0.5 = 1

By determining the parameter K1 for each profile, we can calculate the coefficients of the profile-wave resistance for given angles of attack:

? 1 = 16 3 ? 1 = 4 ? = 0°=0 rad ? ? = 4 ? ? 2 ?? ? 2 ? 1 + ? 1 ? ? 2 ?? ? 2 ? 1 = 4 ? 0 2 ?2.5 2 ? 1 + 4 ? 0.05 2 ?2.5 2 ? 1 = 0.0044 ? = ±5°=±0.087266 rad ? ? = 4 ? ? 2 ?? ? 2 ? 1 + ? 1 ? ? 2 ?? ? 2 ? 1 = 4 ? 0.08726646 2 ?2.5 2 ? 1 + 4 ? 0.05 2 ?2.5 2 ? 1 = 0.0177 ? 1 = 8 ? = 0°=0 rad ? ? = 4 ? ? 2 ?? ? 2 ? 1 + ? 1 ? ? 2 ?? ? 2 ? 1 = 4 ? 0 2 ?2.5 2 ? 1 + 8 ? 0.05 2 ?2.5 2 ? 1 = 0.0087 ? = ±5°=±0.087266 rad ? ? = 4 ? ? 2 ?? ? 2 ? 1 + ? 1 ? ? 2 ?? ? 2 ? 1 = 4 ? 0.08726646 2 ?2.5 2 ? 1 + 8 ? 0.05 2 ?2.5 2 ? 1 = 0.022 ? 1 = 1 ? = 0°=0 rad? ? = 4 ? ? 2 ?? ? 2 ? 1 + ? 1 ? ? 2 ?? ? 2 ? 1 = 4 ? 0 2 ?2.5 2 ? 1 + 1 ? 0.05 2 ?2.5 2 ? 1 = 0.0011 ? = ±5°=±0.087266 rad ? ? = 4 ? ? 2 ?? ? 2 ? 1 + ? 1 ? ? 2 ?? ? 2 ? 1 = 4 ? 0.08726646 2 ?2.5 2 ? 1 + 1 ? 0.05 2 ?2.5 2 ? 1 = 0.0144 ? 1 = 16 3 = 5.333 ? = 0°=0 rad ? ? = 4 ? ? 2 ?? ? 2 ? 1 + ? 1 ? ? 2 ?? ? 2 ? 1 = 4 ? 0 2 ?2.5 2 ? 1 + 5.333 ? 0.05 2 ?2.5 2 ? 1 = 0.0058 ? = ±5°=±0.087266 rad ? ? = 4 ? ? 2 ?? ? 2 ? 1 + ? 1 ? ? 2 ?? ? 2 ? 1 = 4 ? 0.08726646 2 ?2.5 2 ? 1 + 5.333 ? 0.05 2 ?2.5 2 ? 1 = 0.0191 IV. Conclusions 1.

As the angle of attack increases to a certain value, the aerodynamic quality increases. At a certain angle of attack, the quality reaches a maximum value of ????????. This angle is called the most advantageous angle of attack, ??????? ???????? ??????????????ð??"ð??"????????.

2. On the angle of attack of the zero lifting force, where ????=0, the aerodynamic quality will be zero. 3. The effect on the aerodynamic quality of the profile shape is related to the relative thickness and curvature of the profile. The shape of the profile contours, the shape of the sock and the position of the maximum profile thickness along the chord 4. To obtain large values of ????????, the optimum thickness and curvature of the profile, the shape of the contours and the extension of the wing are selected. 5. To obtain the highest quality values, the best shape of the wing is elliptical with a rounded leading edge.

6. The zero lifting force angle ?? 0 is at the intersection of the polar with the axis ????. At this angle of attack, the coefficient of lift is zero (????=0). For the wings of modern aircraft, usually (?? 0 =2º÷0º). For modern wings, ??????? ???????? ??????????????ð??"ð??"???????? lies within (?? 0 =4º÷6º).

Fig. 2: four profiles shown with relative thickness — Figure 1. Fig. 2 :

Figure 2.

?? = ?? ?? = ?0.03731 rad= ? 2.13759°= ? 2°8 ? 15 ?? ? ? = ? 2 .099669 rad=5.710593°=5°42 ? 38 ?? ? = ?ð??"°= ? ?. ????? rad Area AB ? ?? = ? ? ? = ?0.08726646 ? 0.09966865 = = ?0.18694 rad= ? 10.7106°= ? 10°42 ? 38 ?? 2 ?? = ? + ? = ?0.08726646 + 0.09966865 = 0.012402 rad=0.710593°=0°42 ? 38 ?? ? ? = ? 2 ? ?? = ? + ? = 0 + 0.09966865 = 0.099669 rad=5.710593°=5°42 ? 38 ?? ? ? = ð??"°=?. ????ð??"ð??" rad Area AB ? ?? = ? ? ? = 0.08726646 ? 0.09966865 = ?0.0124 rad= ? 0 — Figure 3.

Figure 4. ?

Figure 5. A

Figure 6. 2 ?

The Effect of Supersonic Flows on Different Profiles of Aircraft Wings Global Journal of Researches in Engineering ( ) Volume XVII Issue II Version I — Figure 7. Profile 4 .

Appendix A

A F Bochkarev . Aeromechanics aircraft. Mechanical engineering press, (Moscow
) 1985.
At the points of intersection, we find the angles of attack (?? 1 & ?? 2 ) When flying, where the aerodynamic quality will be the same and necessarily smaller, (Angles of attack with the same aerodynamic quality are carried out from the origin of the coordinates of the secant to the field)
Dynamics of the plane's spatial motion. G S Byshgens , R V Studnev . Mechanical Engineering 1967.
Dynamics of the plane's spatial motion. G S Byshgens , R V Studnev . Mechanical Engineering 1967.
Aerodynamics of aircraft. Dynamics of longitudinal and lateral movement. G S Byshgens , R V Studnev . Mechanical Engineering 1979.
Airplane, pilot and safety of flight. G S Kalachev . Mechanical Engineering 1979.
Flight dynamics. The trajectories of the summerenforcement apparatus, I V Ostoslavsky , I V Strazheva . 1969. Moscow: Mechanical engineering press.
N S Arzhannikov , G S Sadekova . Aerodynamics of aircraft, (Moscow
) 1984.
Flight Dynamics, S D Salenko , A D Obuhovsky . 2014. Novosibirsk: NSTU press.
The angle of attack of the zero lifting force (?) of the aircraft is practically no different from the angle of attack of the zero lift of the wing. Since the lifting force is zero on the angle, at this angle of attack only the vertical movement of the aircraft downward, called a vertical dive, (at an angle of 90º is possible)
Y P Guskov , G I Zaiganov . Airplane flight control, (Moscow
) 1980.

The Effect of Supersonic Flows on Different Profiles of Aircraft Wings

Table of contents

1.

Appendix A