gunt ET 796 User manual

Instruction Manual
ET 796 Gas Turbine as Jet
Engine

i
DTP_3
11/2007
All Rights Reserved G.U.N.T. Gerätebau GmbH, Barsbüttel, Germany 11/2005
Instruction Manual
Please read and follow the safety regulations before the first installation!
Publication-no.: 916.000 00 B 796 03 (A) DTP_3
ET 796 GAS TURBINE AS JET ENGINE

Table of Contents
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
2 System description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1 Function. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.1.1 Jet turbine. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.1.2 Fuel system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.1.3 Starter and ignition system . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.2 Controls. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.3 Layout of the experimental module . . . . . . . . . . . . . . . . . . . . . . . . . 11
2.4 Setting up and maintaining the gas turbine . . . . . . . . . . . . . . . . . . . 12
2.4.1 Checking the gas turbine . . . . . . . . . . . . . . . . . . . . . . . . . . 12
2.4.2 Setting up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
2.5 Operation of the gas turbine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
2.5.1 Preparations for starting . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
2.5.2 Starting up the gas turbine . . . . . . . . . . . . . . . . . . . . . . . . . 17
2.5.3 Operation of the gas turbine . . . . . . . . . . . . . . . . . . . . . . . . 19
2.5.4 Shutting down the gas turbine . . . . . . . . . . . . . . . . . . . . . . 20
2.6 Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
2.6.1 Glow plug . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
2.6.2 Inspecting the turbine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
2.7 Faults and fault rectification. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
2.8 Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
3 Safety instructions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
3.1 Hazards for life and limb . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
3.2 Special safety rules for handling kerosene . . . . . . . . . . . . . . . . . . . 33
3.3 Hazards for unit and function. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
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ET 796 GAS TURBINE AS JET ENGINE
11/2007

4 The open gas turbine process. . . . . . . . . . . . . . . . . . . . . . . . . 37
4.1 Representation in heat diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
4.1.1 Thermal efficiency (ideal) . . . . . . . . . . . . . . . . . . . . . . . . . . 39
4.1.2 Specific work capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
4.1.3 Representation in p/v diagram . . . . . . . . . . . . . . . . . . . . . . 41
4.2 Gas turbine as jet engine. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
5 Experiments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
5.1 Recording of measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
5.2 Air mass flow and fuel mass flow . . . . . . . . . . . . . . . . . . . . . . . . . . 44
5.3 Further characteristic quantities of an aeroplane jet turbine . . . . . . 45
5.4 Evaluation of measurement results . . . . . . . . . . . . . . . . . . . . . . . . . 48
5.4.1 Representation of measured data in diagrams . . . . . . . . . . 48
5.4.2 Calculation of air ratio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
6 Appendix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
6.1 Working sheet for recording measured values . . . . . . . . . . . . . . . . 55
6.2 Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
6.3 Symbols. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
6.4 Parts of delivery. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
6.5 Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
iii
ET 796 GAS TURBINE AS JET ENGINE
11/2007
All Rights Reserved G.U.N.T. Gerätebau GmbH, Barsbüttel, Germany 11/2005

1 Introduction
With the ET796 experimental module the function
and performance of a gas turbine can be demon-
strated and studied on model scale. Gas turbine
systems are used to generate mechanical and
electrical energy:
•Driving electricity generators in power
stations
•Driving compressors and pumps in oil and
gas production
•Driving ships, locomotives and heavy
vehicles
•For the propulsion of aircraft with propeller
and jet engines
Gas turbines are always used when high power
density, low weight and quick starting are required.
Contrary to piston engines, as fluid flow machines
they permit high material flow rates with small
dimensions. In this way lightweight, powerful
drives can be realised.
As the moving parts of a gas turbine only perform
rotary motion, almost vibration free running can be
achieved if the turbine is well balanced. Disad-
vantages are the high gas speeds and high noise
emissions due to the simultaneous connection to
the atmosphere.
In comparison to steam turbines, gas turbines
work at higher temperatures but with lower
pressures. The high temperatures particularly in
the area of the turbine require particularly heat
resistant materials.
1 Introduction 1
ET 796 GAS TURBINE AS JET ENGINE
11/2007
All Rights Reserved G.U.N.T. Gerätebau GmbH, Barsbüttel, Germany 11/2005
Fig. 1.1 Jet engine for the propulsion of
an aircraft

The experimental module includes a one-shaft
system. All components necessary for the
operation of the system are combined in a
compact arrangement on a trolley on castors.
The system is of straightforward construction and
is specially designed for training purposes. The
control and display of all important process
parameters is combined on a control panel.
Computerised data acquisition with evaluation
software permits online logging and graphical
representation of all relevant process variables.
As well as demonstrating how the system works,
the set-up can also be used to undertake
qualitative studies such as to determine the thrust,
and other characteristic data of the gas turbine.
2 1 Introduction
ET 796 GAS TURBINE AS JET ENGINE
11/2007

2 System description
The experimental module includes a complete gas
turbine system with the following subsystems:
–Model gas jet turbine comprising com-
pressor (1), turbine (2), combustion chamber
(3) and thrust nozzle with thrust gauge (4).
–Fuel system comprising tank (6), fuel pump
(7), quick-acting gate valve (8) and control
electronics (9).
–Starter and ignition system with starter
motor (10), auxiliary fuel valve (11) and glow
plug (12).
–Measuring instruments and controls with
temperature, flow rate, speed and pressure
measuring points and associated displays.
These also include the safety elements such
as temperature and speed governors.
A process schematic with all subsystems is given
on the next page.
2 System description 3
ET 796 GAS TURBINE AS JET ENGINE
11/2007
All Rights Reserved G.U.N.T. Gerätebau GmbH, Barsbüttel, Germany 11/2005

4 2 System description
ET 796 GAS TURBINE AS JET ENGINE
11/2007
Fig. 2.1 Prozessdiagram Gasturbine
6
78
9
10 12
3
4
11
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