UA26883U - Turbofan engine - Google Patents

Abstract

A turbofan engine contains propellers, a reducer and a turbine.

Description

Description of the invention

The utility model refers to the field of aircraft engine construction. 2 From the theory of air - jet engines, it is known that the thrust of propellers is calculated according to the formula, see |1Y, p. 355:

KARvV-Mv-t, (1) where KU-Rv is the propeller thrust,

Mv is the propeller power, t is an empirical parameter, and the flight (thrust) power is calculated by the formula, see ibid; formula (11.3):

Mp-KUp-Mv-Up (2) where Mp is the flight speed (portable speed).

The main drawback of formula (1) and other formulas for calculating thrust is the inaccurate representation of the thrust generation process on the propeller blades.

The main drawback of formula (2) is that multiplying by MP gives a very high flight (thrust) power, which leads to a very high efficiency.

The second disadvantage of formula (2) is that this formula does not reflect the traction power of the propeller at

Мп-0о, therefore formulas (1), (2) and others are inaccurate, since it is known that the primary phenomenon is a change in driving forces due to a change in the static pressure of the air flow, a secondary phenomenon is a change in the speed of the air flow, which generates inertial (dynamic) forces, therefore, the propeller thrust formula must be deduced only from the primary phenomenon - the change in driving forces from the change in the static pressure of the air flow.

Known propellers of turboprop engines (TGD), for example AI-24, AI-20 ZMKB "Progress" and others, the kinematic diagrams of which are given in (1| on p. 352. The structural disadvantages of such propellers are the presence of blades of the kinematic zone on the leading edge hard (elastic) shock, see Fig. 1b of the submitted application, which limits the aerodynamic load on the propeller blade, the maximum revolutions (maximum circular speed I) and the axial absolute speed of the air flow Ca, the following design disadvantages of propellers are twisting of the flow at the exit from the blades of the propeller, (ee) increased decibel characteristic, the operation of propellers in the subsonic mode along Ш, low technical and economic indicators (specific thrust, specific mass, specific fuel consumption). On Fig. 1a of the application submitted , the kinematic analysis of the nature of changes in axial velocities and static pressure of the air flow in the control circuit of the H-N propeller is shown in Fig. 1b n of the given application shows the kinematic analysis of the change in the axial acceleration of the air flow in the H-N control circuit 4, which is created on the basis of graphical differentiation of the graph of the change in the axial velocity of the air flow in the control circuit H-Nu, it is shown that in the H-B zone the air flow moves with the increasing acceleration, З о, increases and has a positive value, it is shown that along the leading edge of the propeller blades, the section B, - с Чо instantly changes its sign, which is evidence of the presence of a kinematic zone of a hard h (elastic) impact in this section, which generates powerful shock waves in the oscillatory mode, which spread in all » directions equally. Powerful shock waves in the oscillating mode, which are directed against the flow, slow down the latter, which leads to a decrease in the axial speed of the flow of Ca, which leads to an increase in the angles of attack above (5-7)2, a developed disruption of the flow from the backs of the blades, loss of flight (thrust) the power of the air propeller, the disaster. b Powerful shock waves in the oscillating mode, directed downstream, increase the inertial forces in the compression zone of the B-K flow, see Fig. 1 (appendix) of the submitted application, which leads to an additional compression of the flow in this zone, an additional decrease in the axial velocity of the Ca, which leads to an overload of the blades of the rotor 20 in the B-K zone and an additional increase in the impact force with all the negative consequences, including deterioration of environmental ecology due to an increase in decibel characteristics.

Fe" Powerful shock waves directed downstream reduce inertial forces (resistance forces) in the accelerated flow zone

K-C, which leads to an additional acceleration of the flow in this zone, an additional increase in the axial speed of the C flow; with a simultaneous decrease in static pressure, which leads to underloading of the blades of the propeller in this zone, which, together with overloading of the blades in the V-K zone, changes the aerodynamic load on the blades of the propeller, especially in flight, which leads to increased vibration of the blades, reduction of their gas-dynamic stability of work, breakage of propeller blades.

Figure 1c (appendix) of the submitted application shows a kinematic analysis of the nature of the change in driving forces from the change in static pressure in the H-H control circuit; propeller. for Thus, the presence of a kinematic zone of hard (elastic) impact on the leading edges of propeller blades, see Fig. 1 (appendix) of the submitted application limits the aerodynamic load on the propeller blade, the maximum revolutions (maximum circular speed Ш) and the axial speed of the air flow Ca, above which the unstable operation of the propeller occurs, while the power of shock waves in the oscillatory mode , which are generated in the kinematic zone of a hard (elastic) impact, the direction depends on the density of the flow at Mpl»0O (low air flow temperature, high air humidity, fog,

cloudiness, jet current from the engines of a flying plane, etc.). The kinematic analysis of the nature of changes in axial velocities, static pressure, flow accelerations, driving forces due to changes in static pressure, shown in Fig. 1 of the appendix of the submitted application, for propellers is carried out for the first time, since it is completely unknown in the theory of air-jet engines and propellers , the correct representation of the thrust generation process on propeller blades is also unknown, since all existing formulas for calculating propeller thrust are inaccurate.

Air propellers are also known according to the patent Mo2027902 (Method of creating thrust), (2), in which the three working wheels of the air propellers rotate simultaneously as their revolutions increase along the flow. 70 But in this patent, for a better physical representation and accurate calculation of the thrust for the optimal sizes of propellers, the multiplication of P cNEn in the thrust formula KAR nEN-ReEs, see (|2I), needs a synonymous replacement for

Rner Enesr is the average, brought to the zone of calm flow H, driving force from the change in static pressure in the zone K-C of the propeller at MP-0.

THVD are also known, see (1|, p. 353, fig. 11.2, which was chosen as a prototype. This engine has two air /5 Twints, the hydraulic angles of which are located in opposite directions, and the air propellers themselves are rigidly connected with the first and second rotors of the birotating turbine of the opposite direction of rotation with a decrease in the revolutions of the propellers along the flow.

The main structural disadvantages of existing propellers are the presence of a kinematic zone of hard (elastic) impact along the leading edge of the blades of the first propeller, see Fig. 1 of the submitted application, 2 about the presence of two steep bends of the change in the absolute axial velocity of the air flow (the twisting of the flow after the first propeller, and the spin-up on the second contra-lateral propeller), a very complex, non-technological drive of the propellers through two birotative turbines of gas-dynamic communication , which does not allow to obtain the calculated revolutions of the propellers in the transitional modes of operation, the reduction of the revolutions of the counterrotating propellers in the flow direction, the subsonic mode of operation of the propellers at the circular speed o, the increased decibel characteristic, low technical and economic indicators (specific thrust, specific mass, specific fuel consumption). All the negative consequences of the action of powerful shock waves in the oscillating mode, which are generated in the kinematic zone of a hard (elastic) impact on the leading edge of the blades of the first propeller, are the same as for TD AI-24, AIY-20 propellers.

The basis of the useful model is the task of creating a fundamentally new turboprop fan-powered aircraft engine with increased flight safety and increased technical, economic and environmental indicators (specific thrust, specific mass, specific fuel consumption and a significant reduction in the decibel characteristic of aircraft propellers) by means of: so - calculation of thrust and flight (thrust) efficiency, taking into account the change in area and static pressure in the output cross-sections of propeller blades to regulate their optimal dimensions; ise) - almost complete elimination, up to 8095, of kinematic zones of hard (elastic) impact on the leading edges of the blades of the propeller, which compresses the gas flow; - almost complete elimination, up to 8095, of a very dangerous kinematic defect associated with overloading, especially in flight, of the V-K zone of the propeller blades and their underloading in the K-C zone; - an increase in the absolute axial velocity of the air flow Са at the entrance to the blade of the propeller, which "compresses the flow, with a simultaneous increase in the maximum circular speed Ю to the supersonic value, with an increase in the static pressure in the B-K zone at Mp"0. y The task is solved by the fact that the turboprop fan engine (Fig. 2), in which the propeller blades "" have hydraulic angles rD., the optimal dimensions of which are regulated by the calculation of thrust and flight (thrust)

Efficiency, which is distinguished by the fact that the engine contains a gearbox with two coaxial output shafts connected

With propellers and turbine drive, and hydraulic angles VD. the blades of the first and second air propellers 1, 2 are located simultaneously (in one direction), while the first air propeller is rigidly connected to b» output inner shaft C of the gearbox, on the opposite end of which a gear wheel 6 is rigidly installed, which through intermediate gears wheels 9, 10, rigidly installed on the intermediate shaft 11 of the gearbox, connected (ee) through the gear wheel 12 to the drive shaft 13 of the gearbox, and the second air screw in the direction of the flow is rigidly connected to the coaxial output shaft 4 of the gearbox, on at the opposite end of which a gear wheel 7 is rigidly installed, which through the intermediate gear wheels 8, 10, rigidly installed on the intermediate shaft 11 of the gearbox, is connected to the driving gear wheel 12 and the drive shaft 13 of the gearbox, while the gear ratios of the gear wheels of the gearbox provide an increase rotations of the propellers along the flow, their accompanying rotation with a given law, in which the hydraulic angles of the blades of the propellers will provide the swirling of the air flow in the zone of the accelerated flow is opposite to the direction of rotation with the axial exit of the air flow after the second propeller, and the thrust and flight (thrust) efficiency of the propellers are calculated according to the formulas: "at upo, because t -(yaN osv |; at Mr»o, sr Ner ss

From p

And RNer - RNerzhARNer

Ener-N.-1, at MP-0, because ES, at MP-0,

Rner - 81 at MP",

RE - 1, at MP»o,

Reve pt -|1---- 5 -|«10095, at MP - 0,

RNerEner

ReE пп -|1---2 - -5-.|x 10095, at md 2-0, p -Я-5- p 70 РНери Ner de K - thrust of the second propeller at Мп-0,

K - the thrust of the second propeller at Mp»o,

P is the static pressure in the middle cross-section of the gas-dynamic tract of the blade of the second propeller in the zone of K-Со ср 75 at Мп:0О, reduced to the zone of calm flow Н,

Ensr - the area of the gas-dynamic tract in the middle cross-section H of the K-Co zone of the blade of the second propeller at Мп-0, reduced to the zone of calm flow H, ц - the thickness of the gas-dynamic tract in the middle cross-section of the H-zone of the K-Co blade of the second propeller at Мп:0 , 1 - blade length of the second propeller,

VA hz - the average, reduced to the zone of calm flow H, the driving force from the change in static pressure in the zone sr/РНer

K-C blades of the second propeller at MP-0,

Re is the static pressure in the outlet section Co of the gas-dynamic tract of the blade of the second propeller at two Mpto,

Es is the area of the gas-dynamic tract in the outlet cross-section of the blade of the second propeller at MPd-o, t is the thickness of the gas-dynamic tract in the outlet section of the blade of the second propeller at MP-0,

Rheogs is the resistance force of static pressure in the output cross-section Co of the blade of the second propeller at Мп-0, n is the number of blades of the second propeller, с зо Р - static pressure in the average cross-section G of the gas-dynamic tract in the zone K-Co of the blade of the second propeller

Ner (ee) of the propeller at Mp20, brought to the zone of calm flow H, so

РНер - the area of the gas-dynamic tract in the middle cross-section H of the gas-dynamic tract in the zone K-С of the blade of the second (Се) propeller at Мп20, reduced to the zone of calm flow Н,

Zo 1u is the thickness of the gas-dynamic tract in the average cross-section Г of the gas-dynamic tract in the zone K-Со of the blade of the second s propeller at Mp»

РЕ is the average, reduced to the zone of calm flow H, the driving force from the change in static pressure in the zone

NeroRNer "du K-Si blades of the second propeller at MP?" 0, with s BARI - reduction or increase in static pressure in the average cross-section Г of the gas-dynamic tract in the zone K-C 2 "» of the blade of the second propeller at Mp", p - . s. . . .

Re is the static pressure in the outlet section Co of the gas-dynamic path of the blade of the second propeller at M po,

Kr is the area of the gas-dynamic tract in the outlet section of the blade of the second propeller at Mp»o, k g is the thickness of the gas-dynamic tract in the outlet section of the blade of the second propeller at Mp», b REEr is the static pressure resistance force in the outlet section of the gas-dynamic path of the blade of the second propeller at Mp", vd traction efficiency of the second propeller at Mp-0, para 7 flight (thrust) efficiency of the second propeller at Md"o s" Application of two propellers of simultaneous rotation with increasing revolutions along the flow using additional gearbox leads to the almost complete elimination, up to 8095, of the kinematic zone of hard (elastic) shock in the cross-section D" of the second propeller, which significantly raises the ceiling on aerodynamic overload in the Vo-K zone and aerodynamic underload in the K-Co zone of the propeller blades , c significantly increases flight safety, technical and economic indicators by increasing Ca, static pressure in the zone

Vo-K of the gas-dynamic path of the blades of the second propeller, which makes it possible to solve the task.

The application of the fundamentally new formulas of thrust and flight (thrust) efficiency fully reflects all the physical phenomena that take place during the operation of propellers at M d»O, taking into account the static pressure VA 60 sr in the average cross-section Г of the K-Со zone at a flight speed of Мп- :0О, the area in the average cross-section H of the gas-dynamic tract of the K-C zone (Ensr), the static pressure P in the average cross-section G of the gas-dynamic tract of the K-Co zone at sr

MP20, decrease or increase of static pressure in the average cross-section G of the gas-dynamic tract of the K-C zone" ( 65 Ж АРНер), depending on the relative axial velocity of the air flow Page 8 of the average cross-section of the gas-dynamic tract in the K-Со zone, the force of static pressure resistance in the initial cross-section of the gas-dynamic tract So at Mp (Ros) and Mp»O (RE).

New features in interaction with known features make it possible to obtain the following theoretical and technical results: 1. Fundamentally new formulas of thrust and flight (thrust) propellers are derived, which fully reflect all physical phenomena that occur during the operation of propellers at Mp»0. 2. Increasing the pressure in front of the second propeller up to 260 m/s by introducing swirling air flow in the N-W zone; and the spin-up of the flow in the B.-Co zone makes it possible to replace in the H-B zone the law of movement of air flow particles with increasing acceleration, which takes place in the current propellers of the THVD propeller, with a sinusoidal law of movement of air flow particles with decreasing acceleration, which almost completely, at 8095, eliminates the kinematic zone of hard (elastic) impact on the leading edges of the blades of the second propeller, which compresses the flow and generates thrust. This significantly increases the gas-dynamic stability of the propeller and the ceiling for aerodynamic overload in the B 5-K zone and aerodynamic 75 underload in the K-C zone at MP»0, the ceiling for the circular speed О, which significantly increases flight safety.

Q. By introducing an increase in the revolutions of the next propeller, flight safety is significantly increased, because with the same decrease or increase in the axial speed Са, the angle of attack changes to a significantly smaller value on those propeller blades, where the circular speed of rotation О will be higher. 4. An increase in the relative axial velocity of the air flow in the outlet section C » of the blades of the second propeller is provided by a significantly higher degree of compression of the air flow in the B o-K zone, since the circular velocity OM of the blades of the second propeller is supersonic (up to 425 m/s). 5. According to point 2, significantly reduce the decibel characteristic of propellers in all operating modes, which, along with low fuel consumption, improves environmental ecology. b. According to clauses 2 and 4, the overall dimensions of propellers should be significantly reduced compared to the prototype in order to achieve the same thrust. - 7. Improvement of all environmental and technical and economic indicators of propellers, including traction, fuel consumption, dimensions, weight and others. For example, with the same diametrical dimensions as the propeller fan of the D-27 engine (ZMKB "Progress"), the declared thrust of the propellers will be 8095 higher, which is achieved due to the elimination of the kinematic zone of hard (elastic) impact and the increase in the circular speed of the Y blades and, second propeller. Therefore, the proposed propellers can be applied to M 5-(0.9)MP and can completely replace the current turboprops. 8. The achieved technical result will make these THVD propellers beyond the limits of any competition on the world market. "I

Thus, compared to the prototype, the proposed technical solution contains the above significant differences

From the sign, therefore, meets the condition "Novelty". with

Analogues containing features that distinguish the claimed technical solution from the prototype are not found in other technical solutions when studying this field of technology. Based on this, it can be concluded that the proposed technical solution meets the "inventive level" criterion. "

The proposed turboprop fan engine, see Fig. 2, consists of propellers 1, 2, which are respectively rigidly connected to the output inner shaft З and the output coaxial shaft 4 of the gearbox 5, at the opposite ends of which gear wheels are rigidly installed 6, 7, which through the intermediate gears 8, 9, 10 "from rigidly installed on the intermediate shaft 11, are connected with the leading gear wheel 12, which is rigidly "installed on the drive shaft 13, which is driven into rotation by a single-shaft turbine (in the drawing not shown).

The invention is explained by drawings, where the figures show: o - Fig. 1 (appendix) - criticism of the propellers of existing engines,

Ф - Fig. 2 - kinematic scheme of the propellers that are applied, - Fig. За - the trajectory of the movement of parts of the air flow from the zone of the calm flow H to the exit cross-section of the blades of the second propeller, which compresses and accelerates the air flow, generating thrust at the same time, (оо) 20 - Fig. 36 - the nature of the change in angular velocity (ой, с) and angular acceleration of the air flow (в, с), со - Fig. 3v - a plan of the air flow velocities on the blades of the first and second propeller (of the impeller - RK), - Fig. 3g - the shape of the gas-dynamic path of the blades of the second propeller, which consists of the B2-K compression zone and the air flow acceleration zone K-C 5, in which the thrust of the propeller is generated. 59 The nature of the distribution of static pressure along the trough of the blades (blades), see | Fig. 4a - kinematic analysis of the nature of changes in axial velocities and static pressure in the control circuit H-N., - Fig. 46 - kinematic analysis of the nature of changes in axial accelerations of the air flow, it is the same, but on the contrary, - the nature of changes in dynamic (inertial) forces in the control circuit H-N.U, - FigAv - kinematic analysis of the nature of the change in driving forces depending on the change in static pressure in the control circuit H-N. at MP-0, take-off mode, for deriving the thrust formula and flight (thrust) efficiency of propellers, declared, dB - Fig. 5 - operation of propellers, declared, in dynamics at Mp»0, for example, at Mp-Ser, - Fig. Ba - kinematic analysis of the nature of changes in axial velocities and static pressure in the H-Nu control circuit with Mp-Ser compared to similar ones with Mp-o, - Fig. 56b - k kinematic analysis of the nature of the change in the axial accelerations of the air flow, i.e., just the opposite - the nature of the change of the dynamic (inertial) forces in the control circuit H-Ni at Mp-Sror compared to the similar ones at Md-o, - Fig. 5c - kinematic analysis of the nature of the change driving forces depending on the change in the static pressure in the H-Nu control circuit at Mp-:Cro compared to similar ones at Md-o0.

Let's consider the operation of the declared propellers in the dynamics at MP-0.

During the rotation of the drive shaft 13 with the driving gear wheel 12, the torque through the gear wheels 70 10. 9, 8. 7, 6 is transmitted to two air propellers 1, 2, while the transmission ratios of the gear wheels ensure an increase in the revolutions of the air propellers 1, 2 along the way air flow and accompanying rotation.

A kinematic analysis of the nature of changes in axial velocities and flow accelerations shows that in the N-W zone", see Fig. 4, there is a sinusoidal nature of the change in axial velocities and flow accelerations, this is achieved by the fact that the second propeller has a significantly higher air flow rate than the first propeller. This means, 7/5 that the second propeller injects air through the first propeller, while increasing the relative speed of the air flow at the entrance and exit in the blades of the first propeller m 4, mo. An increase in m at a constant circular speed (04) leads to the swirling of the air flow in the H-B4 zone in front of the first propeller against the rotation of propellers 1, 2.

Thus, the first air propeller does not compress or accelerate the air flow, it serves only as a rotary guide device with a given rotation law, which leads to the twisting of the air flow in the N-W zone. and significantly distinguishes the claimed propellers from all current propellers of the THVD propeller, in which in the N-B zone, see Fig. 1, there is an axial air flow. From zone H, the air flow slowly swirls, see Fig.Za, and reaches the maximum spin in cross-section B. before the first propeller. Under the action of centrifugal forces, which are maximal in section B, a gradient of static rudders is generated: directed to the center of section B. see Fig. 4, 5. This gradient of static pressures pulls the air flow into the bundle before and after the cross-section V.. t

Thus, the gradual increase in swirling of the air flow in the Н-В 4 zone and the significant braking of the air flow in the В . increasing with the acceleration that takes place in the current air propellers of propeller fans, according to the law of movement of air parts with decreasing acceleration, which in the section B » is reduced to zero. The second propeller is already compressing the air flow, see Fig. 3, 4, 5, therefore, the impact remains on the leading edges of the blades, but the power of this impact is 4-5 times weaker than that of current THVD propellers. Winding up of the air flow starts already on the first propeller, see FigZa and ends on the blades of the second ise) z5 air propeller, at the exit of which the air flow has an axial direction. with

It should be noted that the number of blades of the first propeller must exceed the number of blades of the second propeller for a smoother twisting of the flow in the H-B zone 4, and the screw power on the first propeller is significantly less than that on the second propeller.

Thus, reducing the impact force on the leading edges of the blades of the second propeller by 4-5 times is "the basis of increasing the revolutions of the second propeller by 8095 in comparison with existing propellers, switching it to the supersonic mode of operation, increasing the absolute axial velocity of the air flow Sa at the entrance to the blade of the second propeller - up to 26 bO0m/s and increasing flight safety and improvement;" environmental ecology due to a decrease in decibel characteristics and fuel consumption.

Kinematic analysis shows that the direction of dynamic (inertial) forces is always opposite to the direction of air flow acceleration. And the direction of the driving forces from the change in static pressure always coincides with the direction of the gradient of static pressures, upstream - plus, against the flow - minus, for example, in the N-W zone, the driving forces from the change in static pressure are directed downstream (plus), see Fig. 1, 4, 5, in the B-K zone, see Fig. 3g, Fig. 1, 4, 5,

Me, against the flow (minus), in the K-C zone, see in the same place, downstream (plus), in the C-No zone of the reactive currents, driving currents

Go! the forces from the change in static pressure are always zero, the air flow in this zone moves only under the action of inertial forces. co Analysis of the nature of changes in dynamic (inertial) forces and driving forces due to changes in static pressure, see Fig. 1, 4) 4, 5, shows that in the zone of the H-H control circuit; average dynamic (inertial) forces generated in zones n-B", Vo-K, K-So, So-Ni, mutually destroy each other, average driving forces from changes in static pressure in zones

H-V" and V.-K also mutually destroy each other, in the zone of the jet stream So-Ni, the driving force from the change in the static pressure is always zero, because in the jet stream at any values of the static pressure in the outlet section of the blades of the air screw (Re»Rn, Roe-Rn, Re«Ru) multiplication of ReEs is always equal to RniEni. c Thus, the uncompensated zone in which thrust is generated on the propeller blades is the K-C zone, the zone of flow acceleration under the action of driving forces from the change in static pressure, the thrust in which, according to the proposed decision, is calculated as: because at Mp-0O, (3) in -|Acheryansr - Reve r write v5 in (ery i de; at Mp", (4)

where I live

RNer - RNer 5 RNer

Ener U 71, at MP-0,

Eb 1, at Md-0, - »

Rner - Sh. 1, at MP",

RE - 2.1, at Mo»o, that is, the thrust of one blade is the difference between the average driving force in the K-C zone ( uh E ) and the resistance force of 70 РNerbNer

ReoEs brought to the zone of calm flow N. It should be noted that the average static pressure in the average cross-section Г, РИ ; at the flight speed Mp»O, completely depends on the change in the average speed of the average air flow Ser at Mp2O, see the derived thrust formula, and the thrust power of the propeller is always equal to the multiplication of E. Ser "at Mp-o, K.sSr x at Mp o" 0, therefore the flight (thrust) efficiency, according to the proposed solution, is calculated as:

ReE 9 pt -|1--2 5 5 | 10095, with MP - 0,

RNerNer (6)

VA

Japo- 1---2-- - 62 5 |x 1 0095, at MP" 0.8 1

RNerb Ner

The calculation of the thrust of the propellers of the proposed THVD, whose diametral dimensions are equal to the similar rotor fan of the D-27 engine, shows that for the calculated take-off mode at M dpIo so

Sa-26Ω/s, Opah-425m/s, the thrust of the propellers that are declared will be 8096 higher, which is the basis for achieving improved technical, economic, and environmental indicators and solving the task. (uh)

Let's consider the operation of the THVD propellers, which is declared, in dynamics at a flight speed greater than zero, so

Mp»0, for example, at Mp-Seor. Kinematic analysis of the nature of changes in axial velocities and flow accelerations at MP-Sor, see Fig. 5 shows that in flight this character is significantly different from the similar one during bench tests (at M 1-0), see Fig. 4, 5. This is due to the fact that in flight the air flow in the zone

N-N; there is additional work from the transferred kinetic energy tgu 2/2, which is always directed against the flow in this zone, and the alternating work of inertial forces from the change in the flight speed Mp and the change in the relative axial velocities " of the flow C; in the control circuit Н-Н.. Since we are considering the mode of operation of propellers at M d-jet, we do not take into account the work of inertial forces from the change in flight speed Mp. Thus, with Mp-Srsr-sopv on - with any particle of the air flow in the zone of the H-H 5 control circuit, there will be constant additional work "" from the transferable kinetic energy tgm4"/2, which is always directed against the flow and alternating work inertial "forces from the change in the relative axial velocities of the flow C). These two works in the H-Ni control circuit complement each other at the Mp-Sesr-sopv and, according to the Bernoulli equation, change the static pressure, hence the driving forces in the H-Ni control circuit within the limits of the law of conservation of energy. It should be noted that the work of inertial forces from changes in the relative axial velocities of the flow,

F iv, en oMabe - to-aisi- Ma) so de Iv, - the work of inertial forces in the ith cross-section, the 1st and its vision

Go) I is the inertial force in the i-th section,

Figure 7 is the absolute speed of the air flow in the i-th cross-section, 1 tg - the second air flow through the area of the i-th cross-section, 5 a; - acceleration of the air flow in the ith section,

С, - axial relative speed of the air flow in the ith section, с Мп - flight speed, portable speed, compared with the similar one at M 4-0 changes its direction and value depending on the direction and value of the absolute speed of the air flow M abs, generating at this within the limits of the law of conservation of energy, the zone of decelerated and accelerated air flow. в Zone of slowed air flow, for example, zone B-K, B 2-K at MP-0, see Fig. 1, 4 is a zone where the direction of inertial forces coincides with the direction of the absolute speed of the air flow, which generates positive (conditionally) work of inertial forces directed, according to the Bernoulli equation, to the additional compression of the main air flow with a simultaneous decrease in the relative air speed stream S.

Zone of accelerated air flow, for example, zone K-C, K-C»o at Mp-0О, see Fig. 1, 4 is a zone where the direction of inertial forces is opposite to the direction of the absolute speed of the air flow, which generates negative (conditionally) work of inertial forces, directed according to the Bernoulli equation, to additional acceleration of the air flow with a simultaneous increase in the relative axial speed of the air flow and reduction of static pressure. The generation of zones of decelerated and accelerated air flow always occurs within the limits of the law of conservation of energy. Gasodynamic characteristics of the flow in cross section (pressure, relative axial velocity)

They remain the same as at M dO, the absolute kinetic energy of the air flow in the cross-section of It is always zero.

Kinematic analysis shows that in the N-Vo zone, see Fig. 5, the direction of inertial forces coincides with the direction of the absolute speed of the air flow M abso. In this zone, there is an additional compression of the air flow with a simultaneous decrease in the relative axial velocity of the air flow Sy M. In the section H, all the work from the 70 transferable kinetic energy tr Mag/2 goes to the compression of the main flow, therefore, in the section H, the static pressure P" significantly exceeds P , see Fig. 5. The phenomenon of air flow compression in front of the air intake of a turbojet engine (TRD) is known, see |1), p. 82. Since the static pressure increases in the section Vo, the air flow through the propellers increases with increasing flight speed, also increases calculated level of pressure increase P" of the propeller blades, static pressure in the section K, see Fig. 3g, 5, increases.

Kinematic analysis shows that in the Vo-K zone, the zone of air flow compression on the blades of the second propeller, see Fig. 5, Zg, the direction of inertial forces is opposite to the direction of the absolute speed of the air flow M abso. In this zone, under the influence of the negative work of inertial forces, the air flow accelerates with a simultaneous decrease in the calculated degree of air flow compression Pu. This very dangerous phenomenon is also known for TRD, see (1|), p.114, p.327 fig.9.24, only this phenomenon in the proposed application is explained by kinematic analysis.

At Sv, »MpС where Sv, is the axial relative velocity of the air flow in section B», see Fig. 5, there is an uneven loading of the propeller blades: the first zone B of the 5th is overloaded, because the work of inertial forces is directed to additional compression of the air flow with a simultaneous decrease in the relative axial velocity of the air flow, the Y-K zone of the propeller blades following the flow will be underloaded, because the work of inertial forces is directed to the additional acceleration of the air flow with a) simultaneous increase in the relative axial velocity and decrease in static pressure . At MP» Sv, the entire air flow compression zone on the blades of the Vo-K propeller will be underloaded.

It should be noted that powerful shock waves, which are generated in the kinematic zone of a hard (elastic) shock at the entrance to the blade of existing propellers, see Fig. 17, which are directed downstream or against the flow, always lead to an increase in inertial forces in the H zone -B and B-K, which in turn leads to additional compression of the air flow in the zone where the blades are overloaded and additional acceleration of the air flow in the d) zone where the blades are underloaded with all the negative phenomena. "co

There is only one way out of this kinematic, very dangerous defect: it is necessary to eliminate the powerful shock waves that are generated in the kinematic zone of a hard (elastic) shock at the entrance to the blade of the existing propellers and to increase the revolutions of the following propellers, because with the same decrease or increase of the axial speed of the air flow Са, the angle of attack changes to a significantly smaller value on that propeller, where the circular speed of rotation ОО will be higher, which is performed in propellers that are declared to be "a guarantor of the absence of a developed disruption of the flow along the back and along the trough of the air blades propellers, a guarantor of flight safety and significant improvement of technical and economic indicators of propellers. t s Kinematic analysis shows that in the zone K-- the direction of inertial forces coincides with the direction of the absolute h" speed of the airflow M abso. In this zone, under the action of the positive work of inertial forces, there is an additional "compression of the main flow to 20956 with a simultaneous decrease in the relative axial velocity of the air flow C. In this zone, the characteristic of the change in static pressure increases relative to the one at M d-0, therefore, the characteristic of the decrease in static pressure during expansion air flow becomes steeper and we take it) Mp-Sosr, this characteristic passes through the point G, which coincides with the middle cross-section, see Fig. 4. In our case, the cross-sections Uy, G, Ssr coincide, since Mp-Sror, therefore gas-dynamic air flow parameters (pressure, axial relative velocity) remain in cross-section 7 as they are at M dO, ARYer is equal to 0.

It should be noted that the characteristic of the change in static pressure passes through point Г only in two cases: со at Мп-О and Мап-Срор, in all other cases this characteristic passes lower (at М l«Сор ) or higher at 4) Мп» Sir, which will accordingly reduce (- ARYer ) or increase (their ARYer ) the thrust of the propellers, generating from

AR, see the declared formulas.

At the same time, the nature of the propeller thrust change depending on the flight speed M dp will be exactly the same as for the TRD, see |1, p. 49, fig. 124, - the beginning of the description, see |/11, p. 261, fig. 8.48, - the full description. c The nature of the change in thrust of the propellers depending on the flight speed M d according to the stated formulas can also be explained by the dependence of the decrease or increase of the static pressure in the average cross-section Г when the flight speed is set on the change in the relative axial velocity of the air flow in the average 60 section Г ( Avdor from Sir ). At MokhSer, the cross-section G is in the zone of accelerated air flow, since inertial forces are directed opposite to Mabs and the work of inertial forces increases Ssr with a simultaneous decrease (-

АР ), the thrust of the propellers at the same time decreases due to the negative (- АР ), reaches its minimum value, see (1), p.49, fig. 1.24, stabilizes, and with further growth of M pd, the thrust begins to increase even at MpeSer of propellers also reaches the same value as with M 150. At Mp»Seor, the cross-section is already between the cross-sections G and So. At the same time, the average cross-section Г is already in the zone of the retarded flow, Ssr begins to decrease with a simultaneous increase (Х АРЭр ), the thrust of the propellers increases at the expense of the positive (Х АРЭР ). Thus, the nature of the change in Ser when MP increases under the action of inertial forces is a mirror image of the thrust change curve, see (|1), p. 49, fig. 1.24, p. 261, fig. 8.48.

Kinematic analysis shows that in the 4Со zone at Мп-Сор, the direction of inertial forces is opposite to the direction of the absolute speed of the air flow M abs. In this zone, under the action of the negative work of inertial forces, there is an additional acceleration of the air flow to 2095 with a simultaneous decrease in the static pressure below Рn, Еs at 70 This decreases due to a decrease in Й , see Fig. Zg.

Since the characteristic of the change in static pressure at Mp-Seor becomes steeper, the expansion of the air flow to Pn takes place long before the outlet section Со of the blade of the second propeller, see Fig. 5, cross-section A, while in cross-section A, separation zones and currents are generated, which reduce the thrust of propellers.

This phenomenon is common to all propellers, but for the proposed propellers, the angle of separation of the flow from the surface of the blade trough is significantly smaller compared to the same for the existing propellers of rotary fans, which leads to significantly lower thrust losses. This is explained by the smoother flow kinematics in the applied propellers.

Thus, with MP-Sror, despite the loss of thrust due to separation currents, the total thrust of the propellers, which are declared, increases due to the reduction of RE; , see formula 4, and reaches the same value as with Md-0.

Kinematic analysis in the So-Ni zone shows that in the jet jet, see Fig. 5, a zone of accelerated air flow 1--Ni is generated. With an increase in the flight speed MP of the H-th and Y-H zones. by its cross-sections

Her and her gradually approach the initial cross-section C" of the blades of the second propeller, while Rys increases, the air flow through the propellers increases, R. increases and approaches P y, thrust losses from - separation zone A and separation currents in this zone decrease. since zone A gradually approaches the initial cross-section C as the flight speed increases, the thrust of the propellers also increases at M d-Se, reaching its maximum value, which significantly exceeds the thrust of the propellers at M n-0, see), P.261, . (0 fig. 8.48. At Mp se, the fronts of two energy flows H-th and T4-H. with their cross-sections y and ys converge on the cross-section Co of the blades of the propeller. Since the fronts of the air flows in the cross-section y and y 4 are in constant co a powerful oscillatory process, then when they meet in the cross-section So, a powerful standing shock wave is generated, the power of which increases with the increase of Md» Sg, this standing shock wave blocks the flow, Po increases above ise)

Рн, thrust of air propellers gradually decreases and at RE; , equal to Reve, becomes zero. with

Thus, the kinematic analysis shows that the most rational mode of flight of propellers

THVD, which is declared, is a mode when M pes, lv in our case M1-:O0.9MP, which allows you to completely replace existing turboprops. - c All this gives every reason to state that the propellers that are claimed will have improved and flight thrust characteristics compared to the current propellers of propeller fans due to the almost "" complete absence of a kinematic zone of hard (elastic) impact and can be used for flight speeds up to 0.9 MP with high flight safety and significantly improved technical, economic and environmental indicators. Thus, the application of a method of kinematic analysis of the nature of changes in axial velocities, flow accelerations, driving forces from changes in the theory of air-jet engines and the theory of propellers of static pressure allows not only to correctly derive the thrust formula, the flight (thrust) efficiency of propellers, which significantly improves our understanding of the thrust generation process, but also to reveal all the shortcomings of the current propellers of propeller fans at M dp»0O, associated with the presence of kinematic zones of hard bo (elastic) impact on the input edges of the flap of propellers, shows that it is possible to eliminate this very dangerous shortcoming only by changing the nature of the movement of parts of the air flow in the N-W zone, see Fig. 1, with the increasing acceleration that occurs in the current propellers of propeller fans, on the nature of the movement of parts of the air flow in the H-B zone 5, see Fig. 4, 5, with decreasing acceleration in the propellers that are claimed, this is achieved by the fact that the air flow, due to the introduction of the first propeller, which does not compress and accelerate the air flow, but is used only as a rotary one with a given rotation law the guiding device is twisted in the N-B zone 4 and untwisted in the B.-So zone, see Fig.Za, having an axial direction in the cross-section So, which makes it possible to almost completely eliminate the kinematic zone of a hard (elastic) impact and, on this basis, to increase the revolutions of the second propeller, using a supersonic mode of operation for it, which significantly improves flight safety, increases the flight thrust, reduces the decibel characteristic, which contributes to the achievement of absolutely higher technical, economic and environmental indicators for the propellers that are declared.

Based on the above, it can be concluded that the proposed technical solution can be applied in engineering and satisfies the "industrial applicability" criterion. 65 Sources of information: - Shlyakhtenko S.M. Theory and calculation of jet engines. - Moscow: Mashinostroenie, 1987 - 568 p.

- Patent for the invention Mo2027902, Russia, MIZH ROZNB/0O, GO4019/00. The method of creating traction. /B.Sh. Mamedov;

Publ. 27.01.95.-4s. - Kazanzhan P.K., Tikhonov N.D., Yanko A.K. Theory of aviation engines, Moscow: Mashinostroenie, 1983.

Claims (1)

Formula of the invention 70 Turboprop fan engine, in which propeller blades have hydraulic angles p;, the optimal dimensions of which are regulated by the calculation of thrust and flight (traction) efficiency, which differs in that the engine contains a gearbox with two coaxial output shafts connected to propellers and a drive from the turbine, and the hydraulic angles p of the blades of the first and second propellers 1, 2 are aligned (in the same direction), while the first propeller is rigidly connected to the output internal shaft 75 of the gearbox, on the opposite end of which a gear wheel is rigidly installed 6, which through the intermediate gear wheels 9, 10, rigidly installed on the intermediate shaft 11 of the reducer, is connected through the gear wheel 12 to the drive shaft 13 of the reducer, and the second air screw in the direction of the flow is rigidly connected to the coaxial output shaft 4 of the reducer, at the opposite end of which a gear wheel 7 is rigidly installed, which through intermediate gear wheels 8, 1 0, rigidly installed on the intermediate shaft 11 of the reducer, is connected to the driving gear wheel 12 and the drive shaft 13 of the reducer, while the transmission ratios of the gear wheels of the reducer ensure an increase in the revolutions of the air propellers in the direction of the flow, they are coordinated with the given law of rotation, in which the hydraulic the angles of the blades of the propellers ensure the twisting of the air flow in the area of the accelerated flow opposite to the direction of rotation with the axial exit of the air flow after the second propeller, and the calculation of thrust and flight (thrust) efficiency of the propellers is performed according to 29 formulas: MD - 0, - (RnNerENer -ROg5», at khd o» 0, so zo and Rner - Rner Ж ARNor, so Energy is also at p z 0, Ege -І.і primp - 0, so Erer - at upo » 0, (se; z5 Be primp x 0, cm VE, pr -|1--- - 24«--/(|x 10095, at Ud-b, RnerENer « RE; pd 1-x 10096, at. udo 0, Z s RnerE Ner "» where is - the thrust of the second propeller at ud - 0, p E" - the thrust of the second propeller at Ud z. 0, Reer - the static pressure in the middle cross-section of the gas-dynamic tract of the blade of the second propeller in the zone ime) K-сСа. at md - 0, reduced to the zone of calm flow, (o) En; the area of the gas-dynamic tract in the middle cross-section H of the k-S zone of the blade of the second propeller when (ee) that Mp is 0, reduced to the zone of calm flow, (ee) and, is the thickness of the gas-dynamic tract in the middle cross-section of the H zone K-cS. of the blade of the second propeller at syu" chip 0, - the length of the blade of the second propeller, Reer "Engo 7 Average, reduced to the zone of calm flow H, the driving force from the change in static pressure in the zone sr s K- se of the blade of the second propeller at m - 0, Ro is the static pressure in the outlet cross-section of the S. gas-dynamic path of the blade of the second propeller at the chip 0, 60 y y Ne y y Er - the area of the gas-dynamic tract in the outlet cross-section of the S. blade of the second propeller at ud - b, I- the thickness of the gas-dynamic of the tract in the outlet cross-section of the S. blade of the second propeller at ud - 0, Рей - the static pressure resistance force in the outlet section of the S. blade of the second propeller at ud - 0, 65 П - the number of blades of the second propeller, Rner is the static pressure in the middle cross-section of the gas-dynamic tract in the K-C zone of the blade of the second propeller at ud z" 0, brought to the zone of calm flow, рр: the area of the gas-dynamic tract in the middle cross-section of the gas-dynamic tract in the kK-сС zone. blades of the second air propeller at M" 0, brought to the zone of calm flow, t is the thickness of the gas-dynamic tract in the middle cross-section Г of the gas-dynamic tract in the kK-C zone. blades of the second propeller at m z 0, Reer "Erer - average, reduced to the zone of calm flow H, driving force from the change in static pressure in the zone K-C" of the blades of the second propeller at m x" 0, ЖАРНер - decrease or increase in static of pressure in the middle cross-section H of the gas-dynamic tract in the zone of 75 Kk- S. blade of the second propeller at m zh b, Re - static pressure in the outlet cross-section C. of the gas-dynamic tract of the blade of the second propeller at U z» 0, E; - the area of the gas-dynamic tract in the outlet cross-section of the S. blade of the second propeller at ud z" 0, HT - the thickness of the gas-dynamic tract in the outlet cross-section of the S. blade of the second propeller at ud z. 0.2 RE; - static pressure resistance force in the outlet cross-section S. of the gas-dynamic path of the blade of the second propeller at ud 0, pt - thrust efficiency of the second propeller at m - 0, dB M" flight (thrust) efficiency of the second propeller at U z" 0. - so so s (Se) s « shi s ;» ime) (22) (ee) at 50 syu" p. 60 b5