RU2005219C1 - Method for providing gas dynamic stability of hydrostatic head stages of two-spool gas-turbine engine fan - Google Patents

Abstract

The invention is intended to prevent compressor surge and improves the reliability of the engine. When the engine is reset, a mode reset signal is generated and, if present, the input guide apparatus (BHA) is rotated towards positive values in addition to the air bypass flaps opened by this signal. due to retaining steps, the VHA rotation angle is determined by the formula vfd DfLd where the LDPE is the first PR ° ° The bottom of the rotational speed of the high-pressure compressor rotor Yeni; K. is a coefficient depending on the engine operating mode, for example, the reduced rotational speed of the high-pressure rotor n К Кп „„) Changing the angle of rotation of the BHA in Vdpr / J .. to the side of a positive value can be achieved by dynamically delaying the shift of the BHA, for example, limiting the speed of the executive VNA transfer mechanism

Description

The invention relates to gas turbine engines (GTE) and is intended to prevent surging of a GTE compressor, in particular, an aircraft twin-shaft twin-circuit engine (turbofan engine) having a fan, a medium-pressure compressor on one shaft with a fan (supporting stages - PS - fan torus) supplying air to the internal circuit of the gas turbine engine, as well as a high pressure compressor (HPC) supplying air to the internal circuit of the engine and having rotary stator vanes of the first several stages. Such an engine may have air bypass valves due to PS in the external channel of the engine.

Closest to the proposed one is a method of providing gas-dynamic stability (PSD) of a fan of a gas turbine engine according to an acceleration signal of a rotational speed of an HPC rotor of a high pressure valve, according to which in static modes the signal for controlling air bypass flaps (ZPV) is determined by the difference value (pnd-A pvd ) where pvd is the rotational speed of the high pressure rotor;

the speed of the low pressure rotor; .

A is const, and in variable modes it is the largest pvd.

The disadvantages of this method of providing GDU ZPV PS should include the fact that it requires significant areas for the release of air due to PS to the external channel, which leads to more complex design, increase in size, weight of the dampers and actuator and, as a consequence, to reduce reliability and stability of the engine.

VNA KVD D VCA settings - measure the actual value of the installation angle of the VNA KVD VVHA and apply to the VNA drive a signal proportional to the difference between the actual value of the program value of vNaprogram and the value of the correction angle of the installation of VNA KVD D (R 1 Fig. 1 shows the effect of deviation

(VBHA) from the program value RvnAprog for air flow through the HPC at various modes of operation of the gas turbine engine: ASv.kvd.

 f (Du to the LDPE ADAP OR LDPE ..

WHERE ASv.kvd. - the deviation of the air flow from its value when executing the program IN ON;

 out-of-program deviation of the installation angle of the BHA from the program value;

PVD.PR., pvd.o. - rotor speed KB / ,, is given by TVx or by TVh.kvd.

In FIG. 2 on the characteristics of the subsystem LLS f (Svpso) shows the influence of D u of the VNA on the change in the stock of the gas turbine engine at reset mode,

where LPS is the degree of pressure increase in PS;

Ovpso - air flow through the PS, given by TVh. PS.

Line 1 is the static line of operating modes (LRR), line 2 is the line of movement of the operating point when the mode is reset (for example, from maximum to low gas) when the program is executed:

RVNAPROG f (PVD.PR. or pvd.o). Line 3 - lines of movement of the operating point when the mode is reset, taking into account the flap of the VNA in the direction of positive values in

The aim of the invention is to increase the stability of a gas turbine engine while improving reliability, reducing engine weight and simplifying the design.

The goal is achieved by additionally measuring the total temperature of the air entering the engine or compressor (TVh or TBh.kvd. From the measured values of the air temperature and the speed of rotation of the high-pressure rotor pvd determine the value of the speed of rotation of the HPC rotor pvdpr or pvdo and, based on the obtained value, form the programmed value of the angle of installation of the input guide vane (V ON) of the high-pressure valve (p

pvd determine the amount of correction of the angle of dependence on pvd.

The proposed method may be pea-. It is described in various embodiments of the device, including the one shown in FIG. 3.

Block 1 is a differentiating device, at the input of which a signal is proportional to the value of the PVD, and a signal is generated at the output that characterizes the value of the PVD.

Block 2 - a comparator performing

Comparison of PVD and PVD. Under the condition of pvd pvd, a signal is generated

lh 1 to open the ZPV PS, with pvd PVDPOR - a signal to close the ZPV PS.

Block 3 - actuator ZPV PS (IMzpvPS).

Blocks 1, 2, and 3 implement a prototype control method.

Block 4 - an arithmetic device, the input of which receives a signal characterizing the values of Twx or Twx.kvd which the signal is generated not output

characterizing

288.15

Tvh

288.15

Tvkh.kvd.

Block 5 is an arithmetic device at the output of which a signal is generated that characterizes the LDPE values. or pvd.o.

Block b is an arithmetic device at the output of which a signal is generated proportional to the value of the correction factor KD, depending on the operating mode of the KDu engine f (PVD.PR. or pvd.o.).

Block 7 is an arithmetic device at the output of which a signal is generated characterizing the value of VHA A Block 8 is an arithmetic device at the output of which a signal is generated proportional to the value of vd1 Block 9 is an adder whose output generates a signal proportional to the difference between the values of the actual and program values with subject to amendment D BHA1; RvNA- (RVNAprog + DrVNA1)

Block 10 - a multiplier that generates a signal of influence on IMVnd:

VNA Craig,

where Kreg is the gain.

Block 11 - IMVND.

Block 12 - the sensor of the actual value of the RVND KVD.

The proposed method is described below using this embodiment of the device shown in FIG. 3.

In static modes) signals from blocks 1.4 and 5, characterizing

Claims (1)

The claims METHOD FOR ENSURING THE GAS-DYNAMIC STABILITY OF THE SUBSIDE STEPS OF A TWO-CURRENT GAS-TURBINE ENGINE by measuring the rotational speed of the rotor of the high-pressure compressor, determining from the measured magnitude of the rate of change of the rotational speed, characterized in that 10 fifteen twenty 25 thirty 35 40 45 PVD.P. or pvd.o. arrive at the input of block 8. at the output of which a signal is formed characterizing the values of the LDPE. or pvd.o. The signals received at the inputs of block 9 from blocks 8 and 12, by means of blocks 10 and 11, provide an 8NA extension to the value of its program value When resetting the mode, the units 6 and 7 are connected to the device’s operation. The signal characterizing the value of the CD goes from block 6 to the first input of block 7, where a signal is generated about the amount of correction to the program value for the variables operating modes as pvd kdr. Since pvd 0 and KD0) 0, then ZNA is O, i.e. when the operating mode is reset, the vnAprog grows, thereby increasing the air flow through the substation (see Fig. 1), as well as the gas supply reserves (see line 3 in Fig. 2). Next, the rotation control of the BHA is carried out in the same order as in the static modes (by means of blocks 10 and 1 T). Also, when resetting the mode when the condition pvd pvdpor is fulfilled, as a result of comparing these values, the output of block 2 receives a signal at the input of block 3 to open the SPZ PS. Part of the device that implements the method (the flowchart in Fig. 3 with the exception of blocks 2 and 3) can be used separately, as well as in conjunction with blocks 2 and 3. This method can be implemented using other block diagram devices. In addition, the determination of the correction and the $ PbnAprog may be carried out using schemes other than those presented. (56) French Patent No. 2488696, cl. G 01 P 1/00, 1980. increase the stability of the engine, additionally measure the total temperature of the air entering the engine or compressor, from the measured values of the air temperature and speed determine the value of the rotational speed of the rotor of the high-pressure compressor brought to the entrance to the engine or compressor and form the programmed angle value from the obtained value setting the input guide vane of the high-pressure compressor in terms of the rate of change of the rotation frequency and the value of the temperature D in the engine or the compressor rotational speed of the high pressure compressor rotor determined correction amount setting angle of the input guide apparatus of a high pressure compressor, actual measured value of the installation angle of the input guide apparatus of the high-pressure compressor; and a signal proportional to the difference between the actual value, the program value and the correction angle of the input guide device of the high-pressure compressor is supplied to the drive of the input guide apparatus. 1 I i I T FIG. fy / us i l #