Improvement of Turboshaft Restart Time Through an Experimental and Numerical Investigation

2021 ◽  
Vol 143 (3) ◽  
Author(s):  
Antoine Ferrand ◽  
Marc Bellenoue ◽  
Yves Bertin ◽  
Patrick Marconi
Keyword(s):  
Data Analysis ◽  
Thermodynamic Model ◽  
Critical Parameter ◽  
Sleep Mode ◽  
Test Rig ◽  
Time Saving ◽  
Idle Speed ◽  
Flight Mode ◽  
Startup Process ◽  
Influencing Parameters

Abstract Inflight shutdown of one engine for twin-engine helicopters has proven beneficial for fuel consumption. A new flight mode is then considered, in which one engine is put into sleep mode while the second engine runs at nominal load. The ability to restart the engine in sleep mode is then critical for safety reasons. Indeed, the certification of this flight mode involves ensuring a close-to-zero failure rate for in-flight restarts and a fast restart capability of the shutdown engine (focus of this paper). Fast restart capability is necessary in case of a failure of the operating engine. Indeed, there is no more power available, and the helicopter can lose up to 15–20 meters per second during autorotation. The restart time becomes a critical parameter to limit the loss of altitude. The aim of the paper is to assess the potential restart time saving using an approach combining test rig data analysis and numerical results generated by a thermodynamic model able to simulate at low rotational speed. It is important to understand the detailed phenomenology of the startup process and the various subsystems involved, first to highlight the influencing parameters and then to establish an exhaustive listing of the possible time optimizations. The results of this study show that a fast restart going from sleep mode to max power speed can be up to 60% faster than a conventional restart going from sleep mode to idle speed, which is significantly faster.

Improvement of Turboshaft Restart Time Through an Experimental and Numerical Investigation

2020 ◽  
Author(s):  
Antoine Ferrand ◽  
Marc Bellenoue ◽  
Yves Bertin ◽  
Patrick Marconi
Keyword(s):  
Electric Motor ◽  
Thermodynamic Model ◽  
Sleep Mode ◽  
Test Rig ◽  
Gas Generator ◽  
Time Saving ◽  
Idle Speed ◽  
Flight Mode ◽  
Nominal Load ◽  
Turboshaft Engine

Abstract Inflight shutdown of one engine for twin-engine helicopters have proven beneficial for fuel consumption. A new flight mode is then considered, in which one engine is put into sleep mode (the gas generator is kept at a stabilized, sub-idle speed by means of an electric motor, with no combustion), while the second engine runs almost at nominal load. The ability to restart the engine in sleep mode is then critical for safety reasons. Indeed, the certification of this flight mode involves ensuring a close-to-zero failure rate for in-flight restarts as well as a fast restart capability of the shutdown engine. In this paper, the focus is made on improving the restart time of the shutdown turboshaft engine. Fast restart capability is necessary for flight management reasons. Indeed, in case of a failure of the engine operating close to nominal load while the other one is in sleep mode, there is no more power available and the helicopter can lose up to 15–20 meters per second during autorotation. The restart time becomes a critical parameter to limit the loss of altitude. In the configuration studied, the fast restart is achieved thanks to the electric motor designed to deliver a high torque to the gas generator shaft. This electric motor is powered by an additional battery, more powerful than the conventional one dedicated for standard restarts. The aim of the paper is to assess the potential restart time saving using an approach combining test rig data analysis and numerical results generated by a thermodynamic model able to simulate at very low rotational speed. A gas turbine engine starting process is composed of two main phases: the light-up phase and the acceleration phase. It is important to understand the detailed phenomenology of these two phases as well as the various sub-systems involved, first to highlight the influencing parameters of both phases and then to establish an exhaustive listing of the possible time optimizations. From the test rig campaign, conducted at Safran Helicopter Engines on a high power free turbine turboshaft engine, we are able to accurately break down the phases of the start-up sequence, which helps us to identify what steps of the sequence worth shortening. With the engine performance thermodynamic model, we can then use the information gathered from the test rig analysis to further predict how to save time and to give guidelines for developing new control strategies. The results of this study show that a fast restart going from sleep mode to max power speed can be up to 60% faster than a conventional restart going from sleep mode to idle speed. This is significantly faster, especially if one takes into account the higher final speed targeted by the fast restart.

High Fidelity Modeling of the Acceleration of a Turboshaft Engine During a Restart

2018 ◽  
Author(s):  
Antoine Ferrand ◽  
Marc Bellenoue ◽  
Yves Bertin ◽  
Radu Cirligeanu ◽  
Patrick Marconi ◽  
...  
Keyword(s):  
Initial Conditions ◽  
Combustion Efficiency ◽  
High Fidelity ◽  
Gas Generator ◽  
Idle Speed ◽  
Flight Mode ◽  
System States ◽  
Secondary Air ◽  
Turboshaft Engine ◽  
High Level

In order to decrease the fuel consumption, a new flight mode is being considered for twin-engine helicopters, in which one engine is put into sleeping mode (a mode in which the gas generator is kept at a stabilized, sub-idle speed by means of an electric motor, with no combustion), while the remaining engine operates at nominal load. The restart of the engine in sleeping mode is therefore deemed critical for safety reasons. This efficient new flight mode has raised the interest in the modeling of the restart of a turboshaft engine. In this context, the initial conditions of the simulations are better known relative to a ground start, in particular the air flow through the gas generator is constant, the fuel and oil system states are known and temperatures of the casings are equal to ambient. During the restart phase of the engine, the gas generator speed is kept at constant speed until the light-up is detected by a rise in inter-turbine temperature, then the starter torque increases, accelerating the engine towards idle speed. In this paper, the modeling of the acceleration of the gas generator from light-up to idle and above idle speeds is presented. Details on the light-up process are not addressed here. The study is based on the high-fidelity aero-thermodynamic restart model that is currently being developed for a 2000 horse power, free turbine turboshaft. In this case, the term high-fidelity refers not only to the modeling of the flow path components but it also includes all the subsystems, secondary air flows and controls with a high level of detail. The physical phenomena governing the acceleration of the turboshaft engine following a restart — mainly the transient evolution of the combustion efficiency and the power loss by heat soakage — are discussed in this paper and modeling solutions are presented. The results of the simulations are compared to engine test data, highlighting that the studied phenomena have an impact on the acceleration of the turboshaft engine and that the model is able to correctly predict acceleration trends.

Improving the Innovation of Appropriate Technology in the Home Industry of Pemindangan in Coastal Communities of Tambaksari Village

2019 ◽  
Vol 10 (1) ◽  
pp. 32
Author(s):  
Oktaviani Adhi SUCIPTANINGSIH ◽  
Sucihatiningsih Dian Wisika PRAJANTI ◽  
Dewi Liesnoor SETYOWATI ◽  
Agustinus Sugeng PRIYANTO ◽  
Yoris Adi MARETTA
Keyword(s):  
Data Analysis ◽  
Production Process ◽  
Life Quality ◽  
Cost Effective ◽  
Production Quality ◽  
Appropriate Technology ◽  
Time Saving ◽  
Study Approach ◽  
Data Analysis Technique ◽  
Analysis Technique

The purpose of this research is to analyze the improvement of appropriate technology innovation in home industry of pemindangan in coastal community of Tambaksari Village. The research method used is qualitative with case study approach. The subjects of the research were the home industry of pemindangan, while the informant was the Tambaksari community and the consumers of pindang fish. The method of data collection used observation, indept interview and documents. Data validity technique used data triangulation and data analysis technique used nvivo data analysis technique. The results showed that there was an increase in production quality in home industry of pemindangan using precise technology pan presto pindang pangkon. The production process becomes time-saving, cost-effective and energy-efficient, in addition to the more hygienic production process and the result of pindang fish is more durable. The benefits are increasing to improve the life quality of pemindangan home industry shoppers. The conclusion is that pindang pangkon is one of the appropriate technological innovations that can be used in home industry of pemindangan.

Physical Modeling and Data Analysis of the Dynamic Response of a Flexibly Mounted Rotor Mechanical Seal

1995 ◽  
Vol 117 (1) ◽  
pp. 130-135 ◽  
Author(s):  
An Sung Lee ◽  
Itzhak Green
Keyword(s):  
Data Analysis ◽  
Dynamic Behavior ◽  
Theoretical Work ◽  
Experimental Investigations ◽  
Mechanical Seal ◽  
Test Rig ◽  
The Past ◽  
Recent Theoretical Work ◽  
Face Seals ◽  
Stiffness And Damping

The dynamic behavior of mechanical face seals has been an active area of research over the past three decades. Analytical and experimental investigations have exclusively been devoted to the flexibly mounted stator (FMS) seal. Recent theoretical work on the dynamics of the noncontacting flexibly mounted rotor (FMR) seal has proven that it excels in every aspect of dynamic behavior compared to the FMS seal. The advantages of the FMR seal, however, have to be experimentally verified. This work introduces a physical model (i.e., test rig) for an experimental investigation of the dynamic behavior of a noncontacting FMR seal. Features of the test rig, a new method of modeling and measuring the stiffness and damping of elastomeric O-ring secondary seals, and data analysis procedures will be introduced. Finally, experimental results will be compared with theory.

Overview of Unsteady Phenomena Emerging in a Stalled 1.5-Stage Transonic Compressor

2021 ◽  
Author(s):  
Silas Mütschard ◽  
Jan Werner ◽  
Maximilian Karl ◽  
Christian Kunkel ◽  
Heinz-Peter Schiffer ◽  
...  
Keyword(s):  
Data Analysis ◽  
Gas Turbine ◽  
Stability Limit ◽  
Wall Pressure ◽  
Structural Behavior ◽  
Post Processing ◽  
Test Rig ◽  
Transonic Compressor ◽  
Pressure Fields ◽  
Operating Points

Abstract A new transonic compressor test rig for gas turbine front stages was commissioned at the Technical University of Darmstadt in 2018. In the first measurement campaign numerous transient stall maneuvers were conducted by throttling the compressor beyond its stability limit. Several distinct phenomena can be observed during in-stall operation. This work gives an overview of those different manifestations of stall with focus on classification and characterization. For this purpose, detailed post-processing and unsteady data analysis are conducted providing information in terms of operating points, propagation speeds of disturbances, structural behavior of the rotor as well as unsteady wall pressure fields. The authors propose explanations for the different phenomena and possible influences of the rig on the in-stall behavior are discussed. Finally, an overview of the occurrence of the detected phenomena is given.

An Approach for Data Analysis of Multi-Group Metabonomics Base on Hierarchical-PCA

2012 ◽  
Vol 236-237 ◽  
pp. 779-782
Author(s):  
Li Xin Huang ◽  
Yang Li ◽  
Qi Yun Zhang ◽  
Bing Tao Li ◽  
Guang Bin Shang ◽  
...  
Keyword(s):  
Principal Component Analysis ◽  
Data Analysis ◽  
Response Curve ◽  
Hierarchical Modeling ◽  
Water Extract ◽  
Principal Component ◽  
Principal Component Score ◽  
Time Saving ◽  
Effective Time ◽  
Data Dimensionality Reduction

Datasets of metabolomics of multi-group are becoming increasingly complex, hard to summarize and visualize. Hierarchical Modeling makes the data dimensionality reduction and interpretation much easier by principal component analysis (PCA). Dose-response curve is drawed with the principal component score values. As an example, dataset from Ma Xin Shi Gan Tang (MXSGT) water extract administrated rats plasma collected by LC/MS/MS was used to demonstrate this method. As a result, Hierarchical Modeling based on PCA was proved to be an effective, time saving method for data purification.

Microchemical imaging in biomedical research

1992 ◽  
Vol 50 (2) ◽  
pp. 1118-1119
Author(s):  
P. Ingram
Keyword(s):  
Data Analysis ◽  
Electron Probe ◽  
The Other ◽  
X Ray ◽  
Cell Element ◽  
Physiological Information ◽  
Functional States ◽  
Elemental Maps ◽  
Electron Energy Loss ◽  
Secondary Ion

It is well established that unique physiological information can be obtained by rapidly freezing cells in various functional states and analyzing the cell element content and distribution by electron probe x-ray microanalysis. (The other techniques of microanalysis that are amenable to imaging, such as electron energy loss spectroscopy, secondary ion mass spectroscopy, particle induced x-ray emission etc., are not addressed in this tutorial.) However, the usual processes of data acquisition are labor intensive and lengthy, requiring that x-ray counts be collected from individually selected regions of each cell in question and that data analysis be performed subsequent to data collection. A judicious combination of quantitative elemental maps and static raster probes adds not only an additional overall perception of what is occurring during a particular biological manipulation or event, but substantially increases data productivity. Recent advances in microcomputer instrumentation and software have made readily feasible the acquisition and processing of digital quantitative x-ray maps of one to several cells.

Semi-automated methods for 3-D reconstruction of macromolecular complexes

1995 ◽  
Vol 53 ◽  
pp. 42-43
Author(s):  
B. Carragher ◽  
M. Whittaker
Keyword(s):  
Three Dimensional ◽  
Time Saving ◽  
Macromolecular Complexes ◽  
Symmetry Properties ◽  
Dimensional Reconstruction ◽  
Experienced Operator ◽  
Projection Images ◽  
The Individual ◽  
Natural Symmetry

Techniques for three-dimensional reconstruction of macromolecular complexes from electron micrographs have been successfully used for many years. These include methods which take advantage of the natural symmetry properties of the structure (for example helical or icosahedral) as well as those that use single axis or other tilting geometries to reconstruct from a set of projection images. These techniques have traditionally relied on a very experienced operator to manually perform the often numerous and time consuming steps required to obtain the final reconstruction. While the guidance and oversight of an experienced and critical operator will always be an essential component of these techniques, recent advances in computer technology, microprocessor controlled microscopes and the availability of high quality CCD cameras have provided the means to automate many of the individual steps.During the acquisition of data automation provides benefits not only in terms of convenience and time saving but also in circumstances where manual procedures limit the quality of the final reconstruction.

Perceptions of a Collaborative Professional Learning Program: Seeing the “Bigger Picture”

2020 ◽  
Vol 5 (1) ◽  
pp. 290-303
Author(s):  
P. Charlie Buckley ◽  
Kimberly A. Murza ◽  
Tami Cassel
Keyword(s):  
Data Analysis ◽  
Professional Learning ◽  
Social Communication ◽  
Special Educators ◽  
Service Providers ◽  
Integrative Approach ◽  
Theory Approach ◽  
Learning Program ◽  
Speech Language Pathologists ◽  
Related Service

Purpose The purpose of this study was to explore the perceptions of special education practitioners (i.e., speech-language pathologists, special educators, para-educators, and other related service providers) on their role as communication partners after participation in the Social Communication and Engagement Triad (Buckley et al., 2015 ) yearlong professional learning program. Method A qualitative approach using interviews and purposeful sampling was used. A total of 22 participants who completed participation in either Year 1 or Year 2 of the program were interviewed. Participants were speech-language pathologists, special educators, para-educators, and other related service providers. Using a grounded theory approach (Glaser & Strauss, 1967 ) to data analysis, open, axial, and selective coding procedures were followed. Results Three themes emerged from the data analysis and included engagement as the goal, role as a communication partner, and importance of collaboration. Conclusions Findings supported the notion that educators see the value of an integrative approach to service delivery, supporting students' social communication and engagement across the school day but also recognizing the challenges they face in making this a reality.

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