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In La Solana in Spain a solar power plant with a peak output of about 6.5 MW is in operation. Solar inverters are used to transform the current into line frequency. To protect the inverters from atmospheric influence, the inverters are placed in small buildings. During the transformation process there is a power loss, which is released in heat form. To cool down the electric devices sufficiently and ensure a smooth operation, a earth heat exchanger system was constructed and built by TinniT Technologies. This cooling system is using the fact, that the earth temperature in only a few meters (...
The need for repair rather than replace of gas turbine components is becoming increasingly important to operators in today’s economic climate. The use of commercially available numerical analysis software, computational fluid dynamics (CFD) and finite element (FE) have become well established within Wood Group Light Industrial Turbines Ltd. They have allowed the business to be extremely competitive by being able to rapidly respond to a customers request for a repair which may involve a fluid structure interaction and/or conjugate heat transfer analysis. The software has also been used to...
This paper presents the current status in the development and validation of an advanced Computational Fluid Dynamics (CFD) model, CFD-BWR, which allows the detailed analysis of the two-phase flow and heat transfer phenomena in Boiling Water Reactor (BWR) fuel assemblies under various operating conditions. The CFD-BWR model uses an Eulerian Two-Phase (E2P) approach, and is also referred to as the E2P modeling framework. It is being developed as a customized module built on the foundation of the commercial CFD-code STAR-CD which provides general two-phase flow modeling capabilities. The...
Proper orthogonal decomposition (POD) has been proposed as an approach to analyze complex turbulent flows in piston engines, and as a basis for making quantitative, objective comparisons between in-cylinder velocity fields obtained using high-speed optical diagnostics (e.g., particle-image velocimetry - PIV) and numerical simulations (e.g., large-eddy simulation - LES). Here we explore several POD variants that can be used to analyze statistically nonstationary flows in time-varying domains, such as piston engines, in a well-defined and relatively simple geometric configuration. Systematic...
This study involves helping Manufacturing Company reduce overall production time, starting from concept through production, by finding and correlating the parameters of drag force, lift force, side force, pitching moment, yawing moment, and rolling moment of an Ahmed body, representative of a vehicle. The correlation parameters for the Ahmed body are between the computational fluid dynamics software Star-CCM+ and actual wind tunnel testing at the University of Wisconsin-Milwaukee’s (UWM) wind tunnel at a 0.3 scale prototype made from SOS rapid prototyping material. This small scale Ahmed body...
Detailed CFD models of mineral-insulated metal-sheathed (MIMS) thermocouples are discussed and thermocouple readings in fire environment are validated against experimental thermocouple data for a Hencken burner flame. Thermocouple readings are presented as functions of equivalence ratio, thermocouple diameter, thermocouple orientation, position of the junction, depth of insertion into fire, and sheath surface emissivity. Effects of surface oxidation, sheath diameter, and insertion depth on thermocouple response time are analyzed in detail. Computational results are compared with published...
Detailed CFD models of mineral insulated metal sheath (MIMS) thermocouples are discussed and thermocouple readings in clean flames are verified against experimental thermocouple data for a Hencken burner flame available in the literature. Computational results present thermocouple temperature readings as functions of thermocouple insertion depth in three-dimensional directions. Computational temperature correlations are plotted against non-dimensional insertion depth and insertion height above burner. Overall, predictions showed excellent agreement with experimental data. Deviations occurred...
This paper treats the investigation of the complex internal flow in Sirocco type fans by means of both numerical and experimental methods. In order to improve the design and efficiency of these fans, Computational Fluid Dynamics (CFD) with high-quality, high-resolution structured and unstructured grids are used. Simulations are verified by both integral measurements at a high-precision chamber test rig according to ISO 5801 and by means of Stereoscopic Particle Image Velocimetry (Stereoscopic PIV). Comparison between numerical and experimental data shows a high consistency. Performance curves...
In the present paper the design process of a stabilizer fin is presented. Different computational tools were adopted: a two-dimensional panel-code was used to design the two-dimensional airfoil candidates and an optimizer based on genetic algorithms was used to choose the optimum airfoil. A panel-code and a Navier- Stokes solver were successively adopted to verify the three-dimensional design. The two codes showed similar results at low angle of attacks, but differences enlarged when the angle of attack increased. The fins are also adopted as zero-speed stabilizing fins. The torque moment at...
The present work follows on from a successful validation study into the use of 3D CFD with advanced turbulence modeling to predict narrowband and broadband flow noise in a rectangular cavity (L/D=5,W/D=1) at M=0.85. In the present study, this body of work is extended in three ways: first, from the transonic case to a range of flow speeds, from subsonic through to supersonic, M=0.6 to 1.35. Secondly, comparison is made between three DES variants; two of which are frequently referenced in the literature, namely Spalart-Allmaras and k-ω-SST, and our own variant based on the standard k-ε model as...

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