Termogazodinamicheskih processes in GTE

The calculation parameters are defined in the flow path section selected by the engine (pressure, temperature, flow, speed), the rotational speed of the rotors, the performance (thrust specific fuel consumption, etc.) - Characteristics of compressors and turbines are entered into the model form.

Non-stationary processes in the gas path of the engine components are described by the equations derived from the non-stationary recorded in the form of the basic equations of gas dynamics for compressible continuum: the equations of continuity, momentum and energy.

To illustrate the method of constructing the model below is one way to obtain the equations describing termogazodinamicheskih processes in the main combustion chamber. The equations for calculating the processes occurring in it are used for modeling of processes in other volumes of gas supply to the (tap) and without heat (outer contour, FCC, etc..).

We assume that the combustion heat is supplied to the inlet chamber. Then the energy equation for the camera can be written in the following form:

1 index refers to the temperature of the gas stream prior to mixing, and the index 2 - after mixing.

When determining the rotational speed of the rotors is taken into account for the PTO drive motor and aircraft accessories, which generally is defined as a function of flight conditions and engine performance.

The logical scheme for calculating the parameters in a supersonic nozzle is constructed depending on the ratio of the located and critical drops on it, the values ​​of qKp and

Errors in the calculation using a rolling model are determined mainly by the characteristics of reliability of used engine components.

This model allows for a wide range of operating conditions to carry out calculation of steady-state operation of the engine with an error of no more than 1%. .3%, And transition - not more than 3%. .5%, Which is enough to meet the challenges of management.

Multimode simplified engine model

A model of this type can be represented as a system of linear differential and algebraic equations with variable coefficients. The methods for constructing such models are based on the assumption of the fulfillment of the similarity criteria for the engine operating modes in a certain range of changes in the external conditions. In addition, assumptions are used that the dynamic properties of the engine are determined solely by the inertia of the rotating masses, the conditions for the equivalence of the effect of fuel consumption in the FCC and the FKp nozzle area on the turbocharger operation mode (for TRDDF) and a number of others are fulfilled.

Read all about the gas turbine engine

Avia.pro