A14 Study on SOFC-Stirling Engine Combined System : Analysis of Engine Performance

To ensure the quality standards in engine testing, a growing research effort is put into the modeling of full engine test cell systems. A detailed understanding of the performance of the combined system, engine and test cell, is necessary e.g. to assess test cell modifications or to identify the influence of test cell installation effects on engine performance. This study aims to give solutions on how such a combined engine and test cell system can be effectively modeled and validated in the light of maximized test cell observability with minimum instrumentation and computational requirements. An aero-thermodynamic performance model and a CFD model are created for the Fan-Engine Pass-Off Test Facility at MTU Maintenance Berlin-Brandenburg GmbH, representing a W-shape configuration, indoor Fan-Engine test cell. Both models are adjusted and validated against each other and against test cell instrumentation. A fast-computing performance model is delivering global parameters, whereas a highly-detailed aerodynamic simulation is established for modeling component characteristics. A multi-disciplinary synthesis of both approaches can be used to optimize each of the specific models by calibration, optimized boundary conditions etc. This will result in optimized models, which, in combination, can be used to assess the respective design and operational requirements.

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Optimization of Stirling Engine Performance Based on Multipoint Approximation Technique

20th Design Automation Conference: Volume 2 — Robust Design Applications; Decomposition and Design Optimization; Optimization Tools and Applications ◽

10.1115/detc1994-0166 ◽

1994 ◽

Author(s):

Vassili V. Toropov ◽

Henrik Carlsen

Keyword(s):

Computing Time ◽

Engine Performance ◽

Stirling Engine ◽

Optimization Techniques ◽

Approximation Technique ◽

Working Cycle ◽

Design Variables ◽

Stirling Engines ◽

Multipoint Approximation ◽

Conventional Optimization

Abstract The ideal Stirling working cycle has the maximum obtainable efficiency defined by Carnot efficiency, and highly efficient Stirling engines can therefore be built, if designed properly. To analyse the power output and the efficiency of a Stirling engine, numerical simulation programs (NSP) have been developed, which solve the thermodynamic equations. In order to find optimum values of design variables, numerical optimization techniques can be used (Bartczak and Carlsen, 1991). To describe the engine realistically, it is necessary to consider several tens of design variables. As even a single call for NSP requires considerable computing time, it would be too time consuming to use conventional optimization techniques, which require a very large number of calls for NSP. Furthermore, objective and constraint functions of the optimization problem present some level of noise, i.e. can only be estimated with a finite accuracy. To cope with these problems, the multipoint explicit approximation technique is used.

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Characteristics of PEFC / Woody Biomass Engine Hybrid Microgrid and Exergy Analysis

Advances in Environmental Engineering and Green Technologies - Optimum Design of Renewable Energy Systems ◽

10.4018/978-1-4666-5796-0.ch008 ◽

2014 ◽

pp. 237-281

Keyword(s):

Exergy Analysis ◽

Woody Biomass ◽

Response Characteristic ◽

Cell System ◽

Stirling Engine ◽

Combined System ◽

Hybrid Microgrid ◽

Exhaust Heat ◽

City Gas ◽

The City

This chapter consists of three sections, ‘Dynamic Characteristics of PEFC / Woody Biomass Engine Hybrid Microgrid’, ‘Exergy Analysis of the Woody Biomass Stirling Engine and PEFC Combined System with Exhaust Heat Reforming’ and ‘Exergy Analysis of A Regional Distributed PEM Fuel Cell System’. The chapter describes the exhaust heat of the combustion of woody biomass engine using a Stirling cycle that was used for the city gas reforming reaction of a PEFC system. The response characteristic of PEFC and woody biomass engine is investigated by the experiment and numerical analysis. Finally, a combined system that uses the exhaust heat of the woody biomass Stirling engine for the steam reforming of city gas and that supplies the produced reformed gas to a PEFC is proposed.

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