Modelling and parametric study of an efficient Alpha type Stirling engine performance based on 3D CFD analysis

The Stirling engine, as an external combustion engine, can be powered using a variety of heat sources including the continuous combustion process thus achieving significantly reduced emissions. Energy systems powered by a Stirling engines meet the needs of various applications not only in the domestic and industrial sections but in military and space gadgets as well. Stirling engines can also be used as cryocoolers in medical applications where they are called to achieve very low temperatures. Each energy system using Stirling Engine optimizes its performance in specific operating conditions. The system capacity depends on the geometric and structural characteristics, the design of the unit, the environment in which the engine is allowed to it works as well as the size of the load. In order to study the function and the efficiency of Stirling energy systems a CHP SOLO 161V -ALPHA TYPE STIRLING ENGINE was installed in the Laboratory of Applied Thermodynamics of NTUA. A thermodynamic analysis has been conducted using appropriate computing codes. The effect of each independent variable on the system performance was investigated. The study was divided into distinct levels of detail, bringing out each variable. Initially, the performance of the heat engine was examined assuming an ideal regenerator. Then, the effectiveness of the regenerator was evaluated as well as its effect on the engine performance, while the effect of the pressure drop and the energy dissipation on the engine efficiency was also investigated. Measurements were conducted using different operational conditions concerning the heating load of the engine. The effect of the geometrical characteristics of the regenerator on power output and engine performance was examined based on the results of a simulation analysis. Moreover, the power output and the efficiency of the machine in relation to the thermal load of the unit and the average pressure of the working medium were investigated. Major performance input characters affecting geometrical and operational parameters of the unit were identified leading to unit optimization with specific combinations leading to increased system performance. Simulation results were validated by comparison to corresponding values obtained by relative experiments conducted with the SOLO unit. Finally, a sensitivity analysis was performed in order to investigate the effect of the operating conditions on the performance of an alpha type Stirling Engine.

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1D modelling of an alpha type Stirling engine

International Journal for Simulation and Multidisciplinary Design Optimization ◽

10.1051/smdo/2013019 ◽

2014 ◽

Vol 5 ◽

pp. A07 ◽

Cited By ~ 4

Author(s):

N. Martaj ◽

P. Rochelle

Keyword(s):

Parametric Study ◽

Heat Exchangers ◽

Compressible Flows ◽

Dynamic Modelling ◽

Stirling Engine ◽

Physical Parameters ◽

Energy Transfers ◽

Optimal Values ◽

D Model ◽

Alpha Type

In this paper, a 1-D model of an half alpha type “double-acting” Stirling engine (made up of two double-acting pistons, two hot heat-exchangers, two cold heat-exchangers and a common recuperator-regenerator for the two separate gas circuits, all that giving two cycles with 180° phasing) is presented. In this architecture, two cylinders, containing, each one, a double-acting piston, are combined in order to operate like two parallel Stirling systems in opposition of phase. This model, derived from Andersen’s model, is used to describe the compressible flows in the half-engine, under energy transfers. A finite-volume numerical method is applied for the equations of energy, mass and momentum assessment. This modelling was carried out using the Matlab/Simulink software. The results of this dynamic modelling relate to one half engine. We obtain the evolution of the physical parameters (density, pressure and temperature), and the (p, V) cycle. The influence of the various assumptions was studied. A parametric study was carried out in order to obtain the optimal values of the geometry of the engine and its ideal speed of operation.

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Numerical simulation of performance of a double-acting alpha-type stirling engine

Science and Technology Development Journal ◽

10.32508/stdj.v18i4.981 ◽

2015 ◽

Vol 18 (4) ◽

pp. 14-21 ◽

Cited By ~ 1

Author(s):

Truong Nguyen ◽

Chin-Hsiang Cheng ◽

Yen-Fei Chen

Keyword(s):

Numerical Simulation ◽

Velocity Fields ◽

Stirling Engine ◽

Cfd Analysis ◽

Power Capacity ◽

Expansion Chamber ◽

Computational Fluid Dynamics Cfd ◽

Alpha Type ◽

Four Cylinders ◽

Periodic Changes

Computational Fluid Dynamics (CFD) analysis is one of the most important powerful processes in commercial engine project, which is going to give the engineers the overall vision that a simulator may want to know about. It could save lots of time and costs before people actually manufacture the engine. This paper deals with numerical simulation of a double acting alpha-type Stirling engine (DASE), which has four cylinders with four pistons moving respectively. In the engine, double actions of the four pistons take place in two opposite chambers in each of four cylinders. For each cycle, the piston alternately moves backand- forth in a cylinder by the connecting expansion chamber of a cylinder to the compression chamber of the next cylinder with a channel, the pressure difference between the expansion and compression chambers is increased and the power capacity of the engine is improved. In this paper, the numerical module is built based on the frame of commercial CFD software (FLUENT). The user-defined functions (UDFs) of the software are adapted so that the movement of those pistons in those cylinders can be simulated. Periodic changes in temperature, pressure and velocity fields in the engine are predicted and the power output of engine is obtained.

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Effects of the regenerator on engine performance of a rhombic drive beta type stirling engine

Energy Sources Part A Recovery Utilization and Environmental Effects ◽

10.1080/15567036.2021.1912853 ◽

2021 ◽

pp. 1-9

Author(s):

Fatih Aksoy ◽

Hamit Solmaz ◽

Muhammed Arslan ◽

Emre Yılmaz ◽

Duygu İpci ◽

...

Keyword(s):

Engine Performance ◽

Stirling Engine

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Design and Fabrication of Stirling Engine for Solar Power Application

Journal of Energy Resources Technology ◽

10.1115/1.4049902 ◽

2021 ◽

Vol 143 (11) ◽

Author(s):

Muhammad Hassan ◽

Hussain Ahmed Tariq ◽

Muhammad Anwar ◽

Talha Irfan Khan ◽

Asif Israr

Keyword(s):

Computer Aided Design ◽

Peak Power ◽

Stirling Engine ◽

Working Fluid ◽

Cad Model ◽

Stroke Length ◽

And Performance ◽

Power Application ◽

Aided Design ◽

Alpha Type

Abstract This paper showcases the designing, fabrication, and performance evaluation of 90-deg alpha-type Stirling engine. The diameters of the hot and cold cylinder are 50 mm and 44 mm, respectively, with a stroke length of 70 mm. The computer-aided design (CAD) model is developed by keeping in mind the ease of manufacturing, maintenance, bearing replacements, and lubrication. After fabrication, the engine is tested by heating the hot cylinder with air as a working fluid. The engine delivered peak power of 155 watts at the temperature of 1123 K and 968 K for hot and cold cylinders, respectively. This developed prototype can be commissioned with the solar parabolic concentrator in the future based on the smooth operation while delivering power.

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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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