Competitive advantages of the MS-21-aerodynamic quality
When creating a promising aircraft for commercial use, an approach should be applied already at the preliminary design stage, which makes it possible to link market analysis, forecast of its needs, and calculation of the cost of production and operation of the aircraft into a single cycle. It is necessary to take into account the parameters of the passenger compartment and cargo compartment, the weight of the aircraft, its aerodynamic quality and speed. All this generally determines the economic and competitive advantages of the future liner.
This approach was applied at the early stages of designing the future MC-21 aircraft by the designers of the A. S. Yakovlev Engineering center of Irkut Corporation. First, the specialists evaluated the relationship of market requirements with the technical and economic characteristics of the liner, after which the technical parameters were optimized in relation to their impact on the project economy as a whole.
Various media outlets often write that the MS-21 has one of the most advanced airframe designs in the world at the moment. At the same time, the volume of composite materials used, a high value of wing elongation, a less financially expensive vacuum infusion technology compared to autoclave technology, and higher aerodynamic quality indicators than those of competitors are noted.
During the development of the MS-21, TsAGI conducted research on the aerodynamics of nine variants of the composite wing geometry. Was conducted thousands of tests, which experts recommended that the designers of the wing, having a sequence number 9. It is the high aerodynamic efficiency of the wing would do without installation for the MS-21 winglets, and leave them as a Foundation for future upgrades.
A higher aerodynamic quality corresponds to a higher lifting force and /or lower resistance to movement.
Aronin G. S. prakticheskaya aerodynamika [Practical aerodynamics], Moscow: Military publishing house of the Ministry of defense, 1962, pp. 68-75.
One of the main goals when creating an aircraft, designers set themselves to achieve the maximum possible value of the value of aerodynamic quality. This characteristic is determined by the ratio of lift to drag, and the required lift with a decrease in drag leads to an improvement in the fuel efficiency of the liner.
New modeling methods for the design of the MS-21 aerodynamic layout, performed on a Lomonosov-class supercomputer at Moscow state University, made it possible to achieve high aerodynamic perfection of the composite wing of large elongation — the aerodynamic quality of the new Russian airliner is 18.2. This value is the main indicator of the competitiveness of the MC-21 in comparison with aircraft of the same class of Boeing (K=15.0) and Airbus (K=16.3).
Achieving K=18.2 required many months of calculations in solving the direct and inverse problems of aerodynamic design with a limited set of optimized parameters. Based on multidisciplinary approaches, the aerodynamic characteristics of the aircraft were determined, which contains a fuselage, a mechanized wing with a slat and flap (taking into account all breaks), pylons, engine nacelles, slat mounts and fairings of flap extension mechanisms, and existing vortex generators on the nacelles. In addition, the engine jets were modeled, and the Reynolds partial differential equations were solved in a three-dimensional formulation in the flow problem.
The MS-21 includes more Russian technological developments than the Superjet. This is not a copy of a Western car.
Leeham News analyst Scott Hamilton
For such a calculation of MS-21 aerodynamics in a complex take-off and landing configuration, taking into account the operation of the power plant, grids with at least 100-150 million cells are required, and the typical calculation time for one point can be several days.
TSAGI General Director, academician of the Russian Academy of Sciences Sergey Chernyshev in 2017 estimated the aerodynamic quality of the MS-21 aircraft to be 7-10 percent higher than that of competitors. "Approximately the same advantage in fuel consumption. But, of course, all this must be confirmed in flight, " the TSAGI Director said in an interview with Rossiyskaya Gazeta in early January 2017.
In February 2016, Leeham News analyst Scott Hamilton wrote: "On the example of the Superjet, we have a well-designed aircraft that is equipped with Western systems. MS-21 follows the same path, but includes more Russian technological developments. This is not a copy of a Western car."
"The MC-21 clearly represents a huge step forward compared to the Superjet," said Addison Schonland, an expert at the American company AirInsight. — It is probably better than the Chinese C919, because it is produced by a company with a richer history in the industry. The Pratt & Whitney engine will allow the MC-21 to demonstrate excellent economic and technical performance, " he said.
According to him, the MS-21 should consume 10% less fuel than the A320peo and 737 MAX, but if the consumption is even at the level of competitors, then this can already be considered an excellent result.
Some weight, aerodynamic and economic characteristics of medium-haul Airliners of comparable passenger capacity: B737 MAX 8, Airbus A320neo and MS-21.
Sometimes it is suggested that the gain in wing aerodynamics will be "eaten up" by the increased diameter of the MS-21 fuselage. Sergey Lyapunov, Deputy General Director of TSAGI and head of the aircraft aerodynamics and flight dynamics complex, agrees that improvements offered by other aircraft engineering disciplines may have a negative impact on the aircraft's aerodynamic parameters. For example, the increase in comfort is largely determined by the size of the fuselage, which leads to a heavier airframe and an increase in drag.
"When developing the MS-21, the discussion was around every centimeter, the balance was found, and the aerodynamic quality of the MS-21 is exactly 5-6% higher than that of competitors, with a larger fuselage size," he said in an interview. ATO.ru Sergey Lyapunov in 2011 before the opening of MAKS-2011.
Head-on arithmetic gives a more fundamental advantage to the Russian airliner. A comparison of the DATA from the table above shows that the MS-21's aerodynamics are 21.3% better than the B737 MAX and 11.6% better than the A320neo.
Prospects for the development of transport aircraft. Proceedings of the Moscow aviation Institute. Issue # 90
Supercomputer modeling in aerospace applications. Academician of the Russian Academy of Sciences Sergey Chernyshev, General Director of TSAGI.
"The Russian newspaper», To tame the supersonic - interview with Sergey Chernyshev, academician of the Russian Academy of Sciences, General Director of TSAGI.
Aerodynamics of the Boeing 737 (300-900) aircraft)
The new York times, Does the Russian MC-21 have any advantages over Airbus and Boeing?
ATO.ru, Why there are no wingtips on the MS-21
for the Russian aviation website»