Parametric Integral Soft Objects-based Procedure for Thermal Protection System Modeling of Reusable Launch Vehicle

The present paper deals with a modeling procedure of a thermal protection system (TPS) designed for a conceptual reusable launch vehicle (RLV). A novel parametric model based on a scalar field created by a set of soft object primitives is used to assign an almost arbitrary seamless distribution of insulating materials over the vehicle surface. Macroaggregates of soft objects are created using suitable geometric supports allowing a distribution of coating materials using a limited number of parameters. Applications to different conceptual vehicle configurations of an assigned thickness map and materials layout show the flexibility of the model

Multidisciplinary Design of Reusable Re-Entry Vehicles by Optimization and Computational Fluid Dynamics

This paper deals with the development of a multi-fidelity design framework for reusable re-entry vehicles. A multidisciplinary shape optimization procedure, for Low Earth Orbit re-entry missions, is performed using a parametric model able to promote the search for unconventional concept aeroshapes. Low order fidelity methods are adopted in the optimization procedure to obtain several design candidates reasonably consistent with a set of mission requirements and constraints at an affordable computational time. Optimal design candidates are validated performing more reliable Computational Fluid Dynamics simulations in a set of specified waypoints along with the re-entry trajectory

Lifting Entry Analysis for Manned Mars Exploration Missions

In the present work, a feasibility study of a manned Mars entry, descent, and landing mission, performed with a lifting vehicle, is analyzed. Mars entry challenges relate to different atmosphere models; consequently, the effective landing capability of a winged configuration is discussed. An entry trajectory study in the Martian atmosphere assuming both a planar and non-planar three degree-of-freedom model is performed. Peak heat rates and time-integrated heat loads during the descent are computed verifying the entry corridor. It is shown that prescribed aerodynamic performances can be modulated explicitly by varying angle of attack and implicitly with bank-angle modulation. Finally, the resulting trajectory is discussed in terms of g-loads, total range performances, and integral heat load absorbed, in the perspective of future manned exploration missions

Thermal Protection System Design of a Reusable Launch Vehicle Using Integral Soft Objects

In the present paper, a modelling procedure of the thermal protection system designed for a conceptual Reusable Launch Vehicle is presented. A special parametric model, featuring a scalar field irradiated by a set of bidimensional soft objects, is developed and used to assign an almost arbitrary distribution of insulating materials over the vehicle surface. The model fully exploits the autoblending capability of soft objects and allows a rational distribution of thermal coating materials using a limited number of parameters. Applications to different conceptual vehicle configurations of an assigned thickness map, and material layout show the flexibility of the model. The model is finally integrated in the framework of a multidisciplinary analysis to perform a trajectory-based TPS sizing, subjected to fixed thermal constraints

An optimization-based procedure for self-generation of Re-entry Vehicles shape

In the present paper a multidisciplinary optimization procedure for the self-generation of re-entry vehicle shapes has been developed. The procedure relies on a novel parametric model of blended wing-body shapes which is used to create a re-entry configuration around a fixed volume. The flexibility of the model allows us to create lifting body or winged re-entry vehicle from an optimization procedure as monolithic bodies. Multidisciplinary analysis is performed with engineering methods valid in conceptual design. Results of shape optimization for a minimum mass configuration, performed for a Low Earth Orbit Re-entry mission, confirmed the suitability of the procedure by indicating a decrease of vehicle mass configuration that is obtained by reducing the wingspan parameter for a conceptual lifting body configuration

Multi-objective optimization for re-entry spacecraft conceptual design using a free-form shape generator

In this paper we developed a multi-disciplinary, multi-objective optimization procedure for the shape generation of re-entry spacecrafts performing conventional landing from a Low Earth Orbit return mission. A special free-form parametric model, able to define complex vehicle shapes with no explicit support surfaces, was defined and used for this purpose. Model capabilities have been preliminary validated by emulating the HOPE-X vehicle prototype and computing the aerodynamic coefficients at Mach number 2 and 10. Multi-objective optimization has been performed by considering a multidisciplinary approach comprising aerodynamic analysis, trajectory estimation, and heating analysis starting by fixed waypoints along the descent path. A Pareto front based on mass and cross range objective functions was generated, highlighting the existence of several design scenarios: minimum mass, maximum winglet, maximum cross range. The existing trade-offs between the objective functions were related mainly to bank angle values and vehicle length, featuring main design trends