Coursework

Paper

Course project.

ENGINE, BLADE MACHINE, COMPRESSOR, COMBUSTION CHAMBER, TURBINE, NOZZLE, POWER, EFFICIENCY, GUIDE VANES, IMPELLER, THERMOGASODYNAMIC CALCULATION, CALCULATION OF MAIN PARAMETERS

Gas-dynamic design of low-pressure compressor of bench engine CFM562 with thermogasodynamic calculation elements is considered. Design calculation of the main parameters of the low pressure compressor was made. Its gas-dynamic calculation was made, as well as the calculation necessary for profiling of the impeller blade. Blade profile built

The parameters characterizing the main nodes of the engine were received: compressor of low pressure (CLP), combustion chamber (CC), turbine of high pressure (THP), nozzle and specific parameters of the engine in general.

Basic conventions and abbreviations

a is the speed of sound, m/s; grate throat size, m;

- critical speed, m/s;

b-chord of profile line connecting extreme points of middle line of profile, m;

b/t - density of the compressor stage grille

c-speed of air or gas in absolute motion, m/s;

- maximum profile thickness, m;

- relative diameter of the bushing;

D- diameter, m;

- parameter of rotor blades height, m;

F - area of the flow section m2;

G- mass flow rate of air or gas, kg/s;

- productivity factor;

- theoretical head created by compressor, J/kg;

- theoretical turbine operation, J/kg;

- flight altitude, m;

- spent head, J/kg;

- head expended ratio;

h- height of flow section, m;

- blade height, m;

Re- Reynolds number;

s - entropy;

S - axial width of the blade, m; current line;

t - grid spacing, m;

- relative grid pitch;

T - temperature, K;

u - circumferential speed; m/s;

V- volume, m; 3

- flight speed, m/s;

w-speed in relative motion, m/s;

, - abscissa of location of maximum thickness of profile and boom of deflection of middle line;

- stage loading parameter;

- turbine loading parameter;

z - number of stages, number of blades;

- angles of flow and blades in absolute motion, deg;

- angles of flow and blades in relative motion, deg;

- profile installation angle in the grid, deg;

- flow lag angle in absolute and relative movements, deg, respectively;

- gap value, m;

h/b-blade extension:

i - specific enthalpy, kJ/kg;

k - indicative isoentropes;

- compressor specific operation, J/kg;

- specific turbine operation, J/kg;

l - length, m;

M is the Mach number; torque, N m;

m - weight, kg;

- compressor drive power, kW;

- power on the turbine shaft, kW;

n - rotation speed min1; polytrope indicator;

p - pressure, Pa;

- gasodynamic functions;

r - profile edge radius rounds, m;

- relative radius;

R - gas constant, J/( kg K);

- angle of deflection (rotation) of flow in the blade machine grid in absolute and relative movements, deg, respectively;

- loss factor;

- stress parameter in turbine blades;

- speed factor in nozzle unit;

- speed factor in the impeller;

- mass density, kg/m3; degree of reactivity;

- coefficient of preservation (recovery) of total air (gas) pressure in engine elements; tensile stress MPa;

- efficiency factor;

- curvature angle of the profile, deg;

- reduced flow rate;

- assigned resource, h;

- mass flow rate change factor;

- degree of pressure increase (decrease) in the compressor (in the turbine);

- degree of pressure increase (decrease) in compressor (turbine) stage;

- entropy thermodynamic function (relative pressure);

- angular velocity, rad/s;

P-parameter;

IGV - inlet guide vanes;

RK - impeller;

HA - guide vanes:

LP - low pressure;

LM-blade machines:

SA- nozzle unit;

Indexes

0 - related to the section at the inlet to the SA of the turbine stage;

1- related to the section at the inlet to RC of the turbine or compressor stage;

2- related to the section at the outlet of the reactor of the turbine or compressor stage;

3 related to the section at the outlet of the compressor stage VV;

air related to the screw:

input - related to the input;

d-disk;

- peripheral diameter related to the compressor;

medium;

stage parameter;

- related to the turbine; theoretical;

tr- related to friction;

h- hour;

ef - effective;

a- projection to axial direction;

c - absolute;

i- section index;

The remaining designations are explained in the text.

Introduction

In this course work, it is necessary to perform the initial (verification) stage of the design of the TBG working cycle according to the specified cycle parameters, which are presented in Appendix 1. As a prototype, the CFM562 single-stage TRDD is adopted.

This work includes four parts. In the first part, it is required to perform a check thermogasodynamic calculation of the engine, in the second part make a selection of parameters and build a diagram of the flow section of the low-pressure compressor. In the third, calculate the parameters at this stage, select the twist law and calculate changes in the flow parameters along the radius (height of the blade) of the designed first stage of the LPC, in the fourth part it is necessary to profile the working blades of the designed degree in three reference sections (periphery, average diameter, bushing).

The purpose of designing the working process of the gas turbine engine and one of its main units (compressor) is to determine the parameters of the thermogasodynamic state of the working medium in the characteristic sections of the engine, as well as to evaluate the main geometric, kinematic and thermodynamic parameters of the compressor as a whole and its individual stages, which provide calculated values ​ ​ of specific and general parameters of the engine.

Conclusion

In this work, the design calculation of the engine flow section was made, the prototype of which is the CFM562 TRDD during the calculation process, the diameters and flow sections of the compressor cascades and high-speed turbines and the necessary rotational frequencies were determined and agreed upon.

Meridional section of flow part is calculated and constructed. The obtained data are initial for further design of HP turbine. A thermogasodynamic calculation of the turbine was made, during which its geometric dimensions were specified, kinematic parameters of the stage at the middle radius were determined, the law of changing the circulation along the radius was chosen and speed triangles at three radii of the blade rim of this stage were determined.

The impeller blade has been profiled.