TURBOFAN ENGINE DESIGN

These notes are part of my previews course project.i hope will be usefull for some people.

Brief description of designed engine construction

           Aircraft engine designed is a high by-pass dual rotor axial-flow advanced technology turbofan engine. It is designed for application on short and middle range aircrafts.Engine has following main parts: inlet unit, compressor unit, combustion chamber unit, turbine unit, casing, exhaust nozzle and thrust reversing unit.

Transonic fan and attached stages are driven by low pressure turbine. For provision of smooth streamlining of fan, wheel nose fairing is used. Aircraft engine designed has axial double-spool compressor. Number of stages is following: Fan – 1+3 attached stages; high pressure compressor – 9. Pressure ratio at take-off mode: in LPC – 1.6; in HPC – 14.5; summary – 24.5.

          Combustion chamber is annular type, made with modern technology, providing convenient operation and reparability.Turbine is axial type, reactive. Number of stages: HPT – 1; LPT – 4. Discs, blades and vanes of HPT are air-cooled; discs of LPT are air-cooled too.

Fuel: Jet fuel, TC-1, T-1, T-2, JET-A, -B, MIL-T-5624G JP-1, JP-4, JP-5, MIL-T-83133 JP-8

Oil: МК – 8, МК – 8П

Oil consumption: not more than 0.6  kg/h

Warranty lifetime – 30000 hrs . High and low pressure rotors don’t have mechanic link and different rotational frequency. Direction of rotors HPC and LPC rotation is left. Aircraft engine designed has 3 major modules that can be separated from the assembly to perform certain maintenance operations. 

These 3 major modules are fan major module, core major module and low pressure turbine major module. 

Peculiarities of engine construction

Compressor – axial, two-spool, thirteen stages (4 stages – LPC, 9 stages – HPC), HPC inlet  guide vanes – adjusted, HPC air bypass.

Combustion chamber –  annular type with pilot burners.

Gas turbine – 5 stages (1 stage — HPT, 4 stages — LPT), with cooling nozzle diaphragm vanes and blades of  HPT.

Jet nozzles of both flows – subsonic, not regulated.

Starting system – system with air turbo starter.

Description of the used constructional materials

Constructional materials chosen for designed engine structural elements are shown in table 2.1. These materials were chosen with accordance to all necessary requirements.

Table 2.1 – Designed engine constructional materials

Name of the assembly and detail	Constructional material
Intake fairing (spinner)	ВТ-6
Fan blade	ВТ-8
Fan disc	ВТ3-1
Casing	ВТ-6
Add blades	ВТ-М
Add guide vanes	ВТ-4
Diffuser	ВТ-8
HPC rotor discs of the:
1-8 stage	ВТ-8
9-11 stage	ВТ-18В
12-13 stage	ЭИ698ВД
HPC blades of the:
1-8 stage	ВТ3-1
9-13 stage	ЭИ-797ВД
HPC stator guide vanes of the:
1-5 stage	ВТ3-1
6-12 stage	ЭИ787ВД
13 stage	ВЖЛ-14
HPT discs	ЭИ698ВД
HPT blades	ЖС6УВИ
LPT discs	ЭИ698
LPT blades	ЖС6К

Name of the assembly and detail	Constructional material
Turbine casing	Х18Н9Т
Combustion chamber casing	ВЖ102
Flame tubes	ХН60В
Nozzle diaphragm	ЖС6К
Turbines deflectors	ЭИ437Б
HP rotor shaft	ЭП517-Ш
LP rotor shaft	ЭП517-Ш
Exhaust nozzle	ОТ4-1
Bearings	ШХ-15
Bolts, casing nuts	30ХГСА
Graphite seals	АГ1500
Contact ring seals:
Rings	Бр018
Outer rings	12ХН3А
Rubber sealing rings	Oil - and thermo- resistant rubber