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Products  |  Thermal Engineering and HVAC  |  Power Engines and Machines  |  ET 794
ET 794 Gas Turbine with Power Turbine Show data sheet (pdf file) Print page
Technical Description

  Gas turbines with free-running power turbines are used primarily as drive systems for widely varying power requirements in power plants and on-board ships, locomotives and motor vehicles.
  The ET 794 trainer investigates the behaviour during operation of a system with two independent turbines in a two-shaft arrangement. One turbine (the high-pressure turbine) drives the compressor and the other turbine (the power turbine) supplies the effective power. Changes in power output in the power turbine have no influence on the compressor, which is able to keep running at optimum speed at the best efficiency point.
  The trainer includes the following components: compressor, tubular combustion chamber and turbine; fuel system; starter and ignition system; lubrication system; power turbine; generator; and measuring and control equipment. The gas turbine works as an open cyclic process, with the ambient air being drawn out and fed back in.
  The ambient air drawn in is brought to a higher pressure in the single-stage radial compressor. When the air enters the combustion chamber only part of it is used for combustion. This air is decelerated with the aid of a turbulence generator such that the added fuel is able to burn with a stable flame. The greater portion of the air is used to cool the combustion chamber components, and is mixed into the combustion gases at the end of the combustion chamber. This reduces the gas temperature to the permissible inlet temperature of the turbine.
  The gas flows out of the combustion chamber into the single-stage radial turbine and discharges a portion of its energy to the turbine. This energy drives the compressor. In the power turbine the gas discharges the remaining portion of its energy, which is converted into mechanical energy and drives a generator. The electrical energy generated is dissipated using braking resistors. The experiment is started with the aid of a start-up fan.
  The speed, temperatures and pressures and the mass flow rates of the air and fuel are recorded and displayed using sensors. Typical characteristic variables are determined.
  The well-structured instructional material sets out the fundamentals and provides a step-by-step guide through the experiments.

Learning Objectives / Experiments
- determining the shaft power
- determining specific fuel consumption
- recording the characteristic of the power turbine
- determining the system efficiency

* Simple model of a gas turbine1
* Two-shaft arrangement with high-pressure turbine

  and power turbine1
* Display and control panel with illustrative process
* Propane gas as fuel

Alternative products
ET 792 -- Gas Turbine
ET 795 -- Simulation of a Gas Turbine
[1] experiments relating to the function and behaviour during operating of a gas turbine in a two-shaft arrangement
[2] operation with power turbine and generator
[3] asynchronous motor with frequency converter as generator
[4] start-up fan to start the gas turbine
[5] conversion of generated electrical energy into heat using four 600W braking resistors
[6] effective silencing at intake and exhaust for laboratory operation
[7] sensors record all relevant data visualised on displays in the process schematic
Technical Data

Compressor and high-pressure turbine 
- speed range 60.000...120.000min-1
- max. pressure ratio: 2.2

- max. fuel consumption: 120g/min
Power turbine
- speed range: 10.000...40.000min-1
- mechanical power: 0...1,5kW
- electrical power: 0...1kW
Asynchronous motor: 2,2kW/400V
Measuring ranges
- temperature: 6x -200...1.000C / 1x -40...1.300C 
- speed: 0...199.999min-1
- electric power: 0...1.999W
- air inlet velocity: 0...28m/s
- fuel mass flow rate: 1,5...10,5kg/h
- fuel supply pressure: 0...25bar
- fuel nozzle pressure: 0...4bar
- combustion chamber pressure loss: 0...2kPa
- gas turbine inlet pressure: 0...2,5bar
- power turbine inlet pressure: 0...250mbar

Dimensions and Weight
LxWxH: 1.500x670x1.800mm
Weight: approx. 310kg
Required for Operation
400V, 50/60Hz, 3 phase or 230V, 60Hz, 3 phase
Cooling water: 200L/h, propane gas: 4...15bar
Ventilation 500m/h, exhaust gas routing required
Scope of Delivery
1 trainer
1 set of instructional material
Order Details
061.79400  ET 794  Gas Turbine with Power
© 2005 G.U.N.T. Gerätebau GmbH