Plume-On Base Drag Prediction Including Three-Dimensional and Real-Gas Effects

A numerical model was included in a three-dimensional viscous solver to account for real gas effects in the compressible Reynolds averaged Navier-Stokes (RANS) equations. The behavior of real gases is reproduced by using gas property tables. The method consists of a local fitting of gas data to provide the thermodynamic property required by the solver in each solution step. This approach presents several characteristics which make it attractive as a design tool for industrial applications. First of all, the implementation of the method in the solver is simple and straightforward, since it does not require relevant changes in the solver structure. Moreover, it is based on a low-computational-cost algorithm, which prevents a considerable increase in the overall computational time. Finally, the approach is completely general, since it allows one to handle any type of gas, gas mixture or steam over a wide operative range. In this work a detailed description of the model is provided. In addition, some examples are presented in which the model is applied to the thermo-fluid-dynamic analysis of industrial turbomachines.

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A Study of the Three-Dimensional Unsteady Real-Gas Flows Within a Transonic ORC Turbine

Volume 3B: Oil and Gas Applications; Organic Rankine Cycle Power Systems; Supercritical CO2 Power Cycles; Wind Energy ◽

10.1115/gt2014-25475 ◽

2014 ◽

Cited By ~ 12

Author(s):

Andrew P. S. Wheeler ◽

Jonathan Ong

Keyword(s):

Three Dimensional ◽

Organic Rankine Cycle ◽

Leading Edge ◽

Rankine Cycle ◽

Gas Flows ◽

Cfd Simulations ◽

Significant Drop ◽

Real Gas ◽

Turbine Efficiency ◽

Real Gas Effects

In this paper we investigate the three-dimensional unsteady real-gas flows which occur within Organic Rankine Cycle (ORC) turbines. A radial-inflow turbine stage operating with supersonic vane exit flows (M ≈ 1.4) is simulated using a RANS solver which includes real-gas effects. Steady CFD simulations show that small changes in the inducer shape can have a significant effect on turbine efficiency due to the development of supersonic flows in the rotor. Unsteady predictions show the same trends as the steady CFD, however a strong interaction between the vane trailing-edge shocks and rotor leading-edge leads to a significant drop in efficiency.

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Problems of Hypersonic Aerodynamics— A Survey

Journal of the Royal Aeronautical Society ◽

10.1017/s0368393100071595 ◽

1959 ◽

Vol 63 (585) ◽

pp. 489-492 ◽

Cited By ~ 2

Author(s):

R. J. Monaghan

Keyword(s):

Hypersonic Flow ◽

Three Dimensional ◽

Separated Flow ◽

Low Pressure ◽

Aerodynamic Heating ◽

Aerodynamic Efficiency ◽

Real Gas ◽

Pressure Drag ◽

Real Gas Effects ◽

Hypersonic Aerodynamics

SummaryReal gas effects are among the major complications of hypersonic flow and this is illustrated by examples of the temperatures and pressures attained when a flow is brought to rest. Once dissociation appears, these depend to a marked extent on the type of compression.In designing for the alleviation of aerodynamic heating there are two distinct cases. The first is the uncontrolled re-entry of a freely falling body, for which it is best to have a shape with a high pressure drag. The second is sustained flight, for which a shape with low pressure drag could be better, radiation giving appreciable control of surface temperature.Low pressure drag accords with design for aerodynamic efficiency and there is scope for research on three-dimensional lifting shapes. There is some discussion of this and also of the philosophy of securing maximum amounts of separated flow.Finally, there is continual emphasis on the need for experimental research, since hypersonic flow fields may differ considerably from those that would be expected by extrapolation of conventional supersonic experience.

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Multishocked, Three-Dimensional Supersonic Flowfields with Real Gas Effects

AIAA Journal ◽

10.2514/3.50505 ◽

1973 ◽

Vol 11 (5) ◽

pp. 657-664 ◽

Cited By ~ 69

Author(s):

P. KUTLER ◽

W.A. REINHARDT ◽

R.F. WARMING

Keyword(s):

Three Dimensional ◽

Real Gas ◽

Real Gas Effects

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Real Gas Effects in Turbomachinery Flows: A CFD Model for Fast Computations

Volume 6: Turbo Expo 2003, Parts A and B ◽

10.1115/gt2003-38101 ◽

2003 ◽

Cited By ~ 2

Author(s):

Paolo Boncinelli ◽

Filippo Rubechini ◽

Andrea Arnone ◽

Massimiliano Cecconi ◽

Carlo Cortese

Keyword(s):

Fluid Dynamic ◽

Computational Cost ◽

Three Dimensional ◽

Industrial Applications ◽

Design Tool ◽

Navier Stokes ◽

Computational Time ◽

Real Gas ◽

Real Gas Effects ◽

Low Computational Cost

A numerical model was included in a three-dimensional viscous solver to account for real gas effects in the compressible Reynolds Averaged Navier-Stokes (RANS) equations. The behavior of real gases is reproduced by using gas property tables. The method consists of a local fitting of gas data to provide the thermodynamic property required by the solver in each solution step. This approach presents several characteristics which make it attractive as a design tool for industrial applications. First of all, the implementation of the method in the solver is simple and straightforward, since it does not require relevant changes in the solver structure. Moreover, it is based on a low-computational-cost algorithm, which prevents a considerable increase in the overall computational time. Finally, the approach is completely general, since it allows one to handle any type of gas, gas mixture or steam over a wide operative range. In this work a detailed description of the model is provided. In addition, some examples are presented in which the model is applied to the thermo-fluid-dynamic analysis of industrial turbomachines.

Download Full-text