26
A. V. Babakov
points. In addition, the study of such flows is complicated by the lack of an adequate
turbulence model.
To determine the aerodynamic characteristics of the landing vehicles and calculate
the descent trajectory, specialized software, on the basis of which a numerical study
of the aerodynamics of segmental and conical shaped vehicles was carried out, is
developed [1]. In [2], the aerodynamic characteristics of the descent module entering
the Martian atmosphere were also calculated for the inviscid gas model, taking into
account the physicochemical processes in the high-temperature shock layer.
In this work, a numerical simulation of the hypersonic flow around the descent
module in the conditions of the Martian atmosphere is carried out. Modeling is based
on a model of viscous, heat-conducting gas (the Navier-Stokes model). The main
attention is paid to the study of non-stationary vortex motion occurring on the side
surface and in near wake of the descent module.
The chapter is organized as follows. Section 3.2 provides a general description of
the numerical method used. Section 3.3 is devoted to a statement of the problem for
numerical simulation of the flow around the descent module. Section 3.4 presents
the results of simulation of unsteady vortex structures of the flow near the lateral
surface of the descent module. Flow patterns and data on gas-dynamic parameters
are presented. The chapter ends with conclusions in Sect. 3.5.
3.2 Numerical Technique
Numerical studies are based on the non-stationary version of the conservative flux
method [3, 4], which allows to calculate flow parameters in the entire integration area
in a unified manner without allocation of features. The numerical model is written
in the form of a finite-difference analogue of conservation laws written in integral
form for each finite volume of the computational grid for each additive characteristic
of the medium. The equations of motion in the methodology used are written in the
Cartesian coordinate system for the Cartesian components of the vector quantities,
regardless of the geometry of the problem and the type of computational grids used.
Numerical calculations were performed on the basis of the developed program
complex “FLUX” [5, 6]. The method and program package are designed to study
the spatially unsteady motion of a compressible gas at sub-, trans-, and supersonic
speeds. The method allows to carry out the numerical studies of the aerodynamics of
aerospace vehicles of complex shape in a wide range of determining parameters. The
software package is based on parallel algorithms of the method and was implemented
on modern supercomputer systems of cluster architecture.
The hardware, which is used for problem under consideration, includes 207
compute nodes with a peak performance of 521 TFlops consisting of 2 Xeon E52690 (Sandy Bridge) processors (64 Gb memory) and 2 Xeon Phi 7110X (KNC)
processors (16 Gb memory) connected by networks based on InfiniBand FDR and
Gigabit Ethernet.
A. V. Babakov
points. In addition, the study of such flows is complicated by the lack of an adequate
turbulence model.
To determine the aerodynamic characteristics of the landing vehicles and calculate
the descent trajectory, specialized software, on the basis of which a numerical study
of the aerodynamics of segmental and conical shaped vehicles was carried out, is
developed [1]. In [2], the aerodynamic characteristics of the descent module entering
the Martian atmosphere were also calculated for the inviscid gas model, taking into
account the physicochemical processes in the high-temperature shock layer.
In this work, a numerical simulation of the hypersonic flow around the descent
module in the conditions of the Martian atmosphere is carried out. Modeling is based
on a model of viscous, heat-conducting gas (the Navier-Stokes model). The main
attention is paid to the study of non-stationary vortex motion occurring on the side
surface and in near wake of the descent module.
The chapter is organized as follows. Section 3.2 provides a general description of
the numerical method used. Section 3.3 is devoted to a statement of the problem for
numerical simulation of the flow around the descent module. Section 3.4 presents
the results of simulation of unsteady vortex structures of the flow near the lateral
surface of the descent module. Flow patterns and data on gas-dynamic parameters
are presented. The chapter ends with conclusions in Sect. 3.5.
3.2 Numerical Technique
Numerical studies are based on the non-stationary version of the conservative flux
method [3, 4], which allows to calculate flow parameters in the entire integration area
in a unified manner without allocation of features. The numerical model is written
in the form of a finite-difference analogue of conservation laws written in integral
form for each finite volume of the computational grid for each additive characteristic
of the medium. The equations of motion in the methodology used are written in the
Cartesian coordinate system for the Cartesian components of the vector quantities,
regardless of the geometry of the problem and the type of computational grids used.
Numerical calculations were performed on the basis of the developed program
complex “FLUX” [5, 6]. The method and program package are designed to study
the spatially unsteady motion of a compressible gas at sub-, trans-, and supersonic
speeds. The method allows to carry out the numerical studies of the aerodynamics of
aerospace vehicles of complex shape in a wide range of determining parameters. The
software package is based on parallel algorithms of the method and was implemented
on modern supercomputer systems of cluster architecture.
The hardware, which is used for problem under consideration, includes 207
compute nodes with a peak performance of 521 TFlops consisting of 2 Xeon E52690 (Sandy Bridge) processors (64 Gb memory) and 2 Xeon Phi 7110X (KNC)
processors (16 Gb memory) connected by networks based on InfiniBand FDR and
Gigabit Ethernet.