Nowadays, besides the goal of enabling sustainable and more economical space access, the accumulation of inoperable objects is rising environmental and safety concerns. Various re-entry estimation software is being developed to promote the design of completely demisable spacecraft and hence mitigate the growth of space debris. Such toolkits perform dynamic analysis to compute the states of the...
The Navier Stokes Multi Block (NSMB) solver is developed in a consortium of different companies and universities in Switzerland, France and Germany. From the start the solver was designed to be used for hypersonic flow simulations, and it has been used in a large variety of ESA and EU funded space projects, among them the IXV (including the post-flight analysis) and the RETALT (Re-usable...
The DLR results of the ATD3 test case 2022 will be presented. The interaction of a free-flying ring with a two-dimensional curved shock wave has been simulated using the DLR TAU code. The flow solver was coupled with a 6-DoF motion module, dynamic grid adaptation has been used to capture the shock waves. A comparison between the numerical results and the experimental test case data will be...
In the frame of the ATD3 working group, coordinated by ESA and CNES, a test case was proposed, representative of the interaction between two fragments generated by the break-up of a space vehicle during the re-entry.
The test was performed experimentally at the VKI Institute, and is described in detail in [1]. A ring is initially suspended over a cylinder (Figure 1), and when the flow enters...
Between 2000 and 2020, the number of man-made objects in orbit around the Earth has increased by approximately 82%, reaching a value close to 20000 objects, from which 53% are fragmentation debris. The current tendency is for the number of space objects to grow with the emergence of new satellite and CubeSat constellations.
To avoid the cluttering of space and decrease the risk of in-orbit...
These 10 last years, the prediction of the space debris survivability during their re-entry and the associated prospective risk on ground are more and more in the scope of scientific research due to its complex multi-physics modeling and its crucial industrial applications, setting-up a permanent trade-off between fidelity of results and CPU costs. The use of the so-called ”high-fidelity” CFD...
Risk assessment of uncontrolled debris re-entering the atmosphere depends on various parameters among which drag and heat rates play a major role. However, those parameters cannot be computed with high fidelity methods such as CFD (Computational Fluid Dynamics) within a reasonable time frame for a full earth re-entry. Thus, correlations are usually used in spacecraft demise codes that use the...
Risk assessment of uncontrolled debris re-entering the atmosphere depends on various parameters among which drag and heat rates play a major role. However, those parameters cannot be computed with high fidelity methods such as CFD (Computational Fluid Dynamics) within a reasonable time frame for a full earth re-entry. Thus, correlations are usually used in spacecraft demise codes that use the...
Simulating destructive re-entry is a demanding task that requires the modelling of non-equilibrium and high-temperature aerothermodynamics, structural and flight dynamics in presence of interacting shock waves, structural deformation, fragmentation and intense heat and mass transfer mechanisms. Three categories of methods can be identified to model re-entry: object-oriented,...
The present study aims at proposing a methodology for coupling the non-equilibrium modelling solver(NEMO) of open source CFD software SU2 Multiphysics with the open source ablation solver Porous material Analysis Toolbox(PATO). SU2-NEMO solves Navier Stokes equations with thermochemical non-equilibrium effects by using finite volume method. Surface heat flux and pressure distribution of...
During atmospheric entry, capsules and space debris are exposed to a flow environment with complex fluid thermochemistry and gas-surface interactions (GSI) that may lead to mass loss and shape change. A promising approach for the numerical simulation of such challenging flows is the use of immersed boundary (IB) and adaptive mesh refinement (AMR) techniques, which offer reliable and efficient...
During an atmospheric re-entry, a vehicle crosses at very high speeds the distinct atmospheric layers characterised by large density variations. The vehicle thus experiences several flow regimes, ranging from free molecular, rarefied (transition, slip) and continuous regimes. These regimes are commonly characterised by a Knudsen number (Kn) range [Kn is defined as the ratio of the mean free...
Composite materials like Carbon Fibers Reinforced Polymer (CFRP) are used in the manufacturing of components for satellites or launcher upper stages. Those materials behave similarly to thermal protection ablators hence show a strong resistance when exposed to high enthalpy flows. For instance, Composite Overwrapped Pressure Vessel (COPV) have been shown to survive the harsh atmospheric...
Among various techniques for Design for demise, maximizing the available heat to demisability is one of the complex problems which may require change in shape to increase the local heat flux, change in size to increase peak heat flux or adding additional energy by exothermic reactions. A frontal cavity has been studied in different applications and has been found to manipulate the heat...
The ISL hyperballistic tunnel is a hypersonic ballistic range. This unique facility in Europe [1] has been recommissioned in 2020 for hypersonic free flight and ablation studies. It is a combination of two two-stage light gas guns and of a 21 m long measurement tunnel.
The two light gas guns are used as model accelerators. Three launch tubes are available with calibres of 10 mm, 20 mm and 30...
High-power lasers are increasingly considered for Active Debris Removal and illumination of low-orbit objects, and progress in high-power laser technology will be instrumental to achieve that aim. One of the main bottlenecks of high-power laser technology is the management of the ever-growing thermal load to which the optical elements are subjected. Scaling up their physical size indefinitely...
