The performance of gas turbines degrades over time due to deterioration mechanisms and single fault events. While occur gradually, events are characterized by occurring accidentally. In the case events, abrupt changes in engine parameters expected. Identifying these as soon possible is referred detection. State-of-the-art detection algorithms based on expert systems, neural networks, special filters, or fuzzy logic. This paper presents a novel technique, which Bayesian forecasting dynamic...

Airborne particles ingested in aircraft engines deposit on compressor blading and end walls. Aerodynamic surfaces degrade a microscopic macroscopic scale. Blade row, compressor, engine performance deteriorate. Optimization of maintenance scheduling to mitigate these effects requires modeling the deterioration process. This work provides model blade row level experimental validation this newly designed deposition test rig. When reviewing previously published work, clear focus industrial gas...

Secondary effects, such as heat transfer from fluid to engine structure and the resulting changes in tip seal clearances affect component performance stability. A clearance model be used transient synthesis codes has been developed. The is derived a state space structure. parameters have identified thermomechanical finite element models. calculates symmetric rotor turbomachinery secondary air system for transients within entire flight envelope. efficiency, capacity, cooling airflows are fed...

This paper presents a novel technique for automatic change detection of the performance gas turbines. In addition to proposed has ability perform prognosis measurement values. The is deemed be new in field turbine monitoring and forms basic building block patent pending filed by authors [1]. used called Bayesian Forecasting applied Dynamic Linear Models (DLMs). idea based on Bayes’ Theorem, which enables calculation conditional probabilities. combination with DLMs (which break down...

Model-based predictive maintenance using high-frequency in-flight data requires digital twins that can model the dynamics of their physical twin with high precision. The models need to be fast and dynamically updatable. Machine learning offers possibility address these challenges in modeling transient performance aero engines. During operation, heat transferred between engine’s structure annulus flow plays an important role. Diabatic is demonstrated non-dimensional transfer maps extend...

This paper addresses the unsteady formation of secondary flow structures inside a turbine rotor passage. The first stage two-stage, low-pressure is investigated at Reynolds Number 75,000. design represents third and fourth stages an engine-representative, turbine. field passage discussed in relative frame reference using streamwise vorticity. A multistage Reynolds-averaged Navier–Stokes (URANS) prediction provides time-resolved data set required. It supported by steady area traverse acquired...

Aircraft engines are subject to deterioration due solid particle erosion. The environmental particulates encountered in service often feature broad size distributions and a generally large scatter of properties. In order numerically calculate the erosive change shape components, experimentally calibrated erosion models required. Due aerodynamic mechanical effects, tests with different have be individually. this study, experiments under high-pressure compressor conditions conducted using...

Aircraft engine condition monitoring is a key technology for increasing safety and reducing maintenance expenses. Current approaches use minimum of one steady-state snapshot per flight. Whilst being appropriate trending gradual deterioration, snapshots result in detrimental latency fault detection. The increased availability non-mandatory data acquisition hardware modern airplanes provides so-called full-flight sampled continuously during These datasets enable the detection faults within...

The change of performance parameters over time due to engine deterioration and production scatter plays an important role ensure safe economical operation. A tool has been developed which is able model on the basis elementary changes numerous construction features. In order consider characteristics fleet as well random environmental influences, a probabilistic approach using Monte Carlo simulation (MCS) was chosen. To quantify impact feature deviations relevant metrics, nonlinear sensitivity...

A comprehensive axial turbine framework model has been developed at the Institute of Aircraft Propulsion Systems, University Stuttgart. It discovers principles a meanline optimisation and shows its advantages for quick prediction optimal parameters considering manufacturing, mechanical aerodynamic requirements. The can incorporate different loss correlations compare their results one same multi-dimensional design parameter space. special attention is paid to influence on values parameters....

Erosive damage done to jet engine compressor blading by solid particles has a negative influence on the aerodynamic properties and hence decreases performance. The erosive change of shape been investigated in multitude experiments ranging from eroding flat plates full engines. basic challenge transfer results very simple tests real life erosion remains. Up date measurement techniques today allow closing this gap. necessary experimental analytical steps are shown. resistance Ti–6Al–4V at...

Recoverable and non-recoverable performance degradation has a significant impact on power plant revenues. A more in depth understanding quantification of recoverable enables operators to optimize operation. OEM curves represent usually degradation, but actual output heat rate is affected by both, degradation. This paper presents an empirical method correct longterm data gas turbine combined cycle plants for Performance can be assessed with standard instrumentation data, which systematically...

The maintenance and reliability of aircraft engines is strongly influenced by the environmental operating conditions they are subjected to in service. A probabilistic tool has been developed predict shop visit arisings respective workscope that depends on these factors. contains a performance model engine number physics-based damage mechanisms (at piece part level). includes variation relevant parameters due production scatter delivers determine deterioration individual parts. Shop modeled...

Laminar separation bubbles form on the back surfaces of aero-engine LP turbine blades. In recent years significant weight and cost reductions performance improvements have been achieved through a better understanding behavior such bubbles. A project is underway at Universita¨t Stuttgart to study possible technique suppress laminar using actuated transition. This paper reports DNS results with without actuation for different frequencies, amplitudes Reynolds numbers, revealing nature...

Abstract More and more attention is being devoted to assessing severity of the engine operation for a high number flights in minimum time. Compressor erosion one physical phenomena contributing this severity. Hence, an effective method developed which allows general judgment with regard compressor erosion. The shortening camber line at blade leading edge selected as parameter describing degree particle impingement conditions experienced by blades throughout flight mission are computed using...

Compressor performance and maintenance characteristics of jet engines are highly influenced by erosion caused ingested, solid particles. For a meaningful prediction these characteristics, an adequate modeling the erosive change shape compressor blades is necessary. This article investigates two different specimens (cylinder blade) out aluminum alloy EN AW-6060 both experimentally numerically. The experiments were performed with test rig using amounts standardized Arizona Test Dust A3...

Ensuring consistent product quality and reproducibility is of paramount importance in additive manufacturing. This applies particular to the laser powder bed fusion procedure. Process parameters, such as power, scanning strategy or inert gas properties, affect generation emissions by-products spatters fumes their removal from process chamber. Numerous authors investigated these effects numerical studies predict suitable parameter sets. However, basic challenge modelling time-dependent...

ABSTRACT Fatigue life reliability often is accounted for through minimal material data. To provide this information within structural calculation, experimental data from specimen testing needs to be processed with statistical methods. The results are either mean or worst case However, in a robust design environment, scatter itself must numerically available. In paper, fatigue test of nickel‐based super alloy at two temperatures taken literature. These according ASTM standard E739 identify...

Atmospheric air is always contaminated by liquid or solid particles of different size, concentration and chemical composition. This leads to performance degradation during the operation stationary flying gas turbines. Erosion deposition along flow path are particular importance. Multiple numerical studies investigated influences these phenomena. However, basic challenge modelling particle wall interaction its data spread with sufficient accuracy remains. In this work a model that estimates...

A mathematical model for the prediction of maximum speed a high pressure turbine following shaft failure event was developed. The predicts compressor and ducting system pre- poststall behaviors such as rotating stall surge after breakage. corresponding time-dependent inlet conditions are used to calculate speed, taking into account friction blade vane tip clearance variations result rearward movement destruction blading. is modeled by one-dimensional, stage-by-stage approach. approach uses...

It is known from thermodynamics that intercooling, recuperation, sequential combustion and constant-volume increase the efficiency of thermal engines. Although these concepts are already analyzed at a high level detail, no comparative structured assessment theoretic realistic for long-range turbofan engines given. In light this generalized thermodynamic mentioned technologies conducted. First, current technological limits ignored propulsive power completely utilized. Theoretic improvements...

Current and future requirements in the verification validation of performance modern aircraft engines lead to continuously increasing on transient capability flexibility Altitude Test Facilities (ATF). These have been investigated via numerical simulations a medium size turbofan core engine. The using engine, document significant influence boundary conditions supplied by ATF dynamic behaviour bypass engines. Variations engine acceleration times compressor stability identified. This leads for...