Session: 32-03 Compressor Design Methods

Paper Number: 101880

101880 - Choking Handling in a 1d Compressor Modelling Fully Integrated in Engine Performance Simulations 

For engine performance modelling, industry standard has been to use turbomachinery 0D maps. With this approach, compressors are modeled like a “black box” providing the output parameters as a function of the input parameters regardless of the number of stages.

 

These 0D maps are only valid at the reference conditions used to obtain the maps, this comprises: the variable geometry settings (IGV/VSV), clearances, blade untwist, Reynolds number, specific heat ratio, intermediate bleeds, etc. When the 0D map is used at off reference conditions, it has to be supplemented with correction factors to take into account the change between the reference condition of the map and the actual ones. 

 

These correction factors are applied as a development of the compressor 0D map in Taylor series, where only the first perturbation term is kept. Therefore, there is no cross terms between effects, even if a compressor with several stages is likely to have cross terms of higher orders.

 

An alternative approach is to implement 1D compressor models in the engine performance cycle. However, the handling of choking conditions has precluded using this type of modelling. This paper provides an innovative approach for choking handling for multi row compressors without hampering the convergence of the engine performance cycle.

 

The objective is for the performance engineer to be able to choose between the 0D and 1D modeling depending of the problem under study.  When investigating effects like water ingestion, heat transfer during transient, etc.  The 1D is a very powerful tool, which can be used also to obtain correction factors that could be applied to a 0D compressor model.

 

To model the aerodynamic performance of the blade row in the 1D model, it is possible to use either the empirical performance models from cascade test, etc. or CFD data.  A key advantage of  using 1D modelling directly in the engine performance cycle is that the representation used is akin to the compressor aerodynamics team, making exchange of information with the performance team more efficient and productive.

Presenting Author: Javier Ruiz-Domingo Safran Aircraft Engines

Presenting Author Biography: Graduated at Polytechnic University of Madrid, aeronautical engineering.
SAFRAN validation leader on the TP400: Certification, test plan, etc.
SAFRAN responsible for the of the LEAP-1A engine integration: Performance, thermal, secondary air system, acoustics.
Currently in the performance department, as expert in jet engine modelling.

Authors:

Javier Ruiz-Domingo Safran Aircraft Engines