How To Develop An Interplanetary Reentry Vehicle

Transcription

1 TPS Design, Development and Verification Approach for IXV Program Elena Brach Prever, Maria Teresa Signorelli, Flavio Camarri, Angelo Denaro (TAS) DOC-TAS-EN-001 Gandolfo Di Vita (ESA) 7th European Workshop on TPS&HS ESA/ESTEC Noordwijk, The Netherlands

2 IXV Program The Intermediate experimental Vehicle (IXV) is an atmospheric re-entry demonstrator, launched by Vega from CSG, conceived to perform a suborbital flight and re-enter the atmosphere experiencing the typical LEO reentry thermal loads, while performing a certain number of experiments related to TPS, AED, ATD and GNC, and validating engineering approach, margin policy and tools used to design and develop the demonstrator and to plan the mission. Among the various technological challenges of the IXV Project, the demonstration of the feasibility of using HS for re-entry vehicles and the acquisition of information on the in-flight behaviour of TPS materials like ceramic and ablative ones, insulations, attachments and seals are the main objectives. 2

3 IXV Mission Breakdown The main IXV objective is to verify that the TPS&HS architecture is able to sustain the environments encountered during the entire mission Nose Heat Fluxes N1 1 Altitude max. altitude 412 km km ORBITAL ARC heat flux [kw/m2] N2 N4 N5 N6 NSK4 NSK5 NSK6 N10 N4S N6S Separation 200 NSK6S N10S time [s] 2 Reference Trajectory 3D view 5 1 ASCENT AVUM fallout P80 LIBREVILLE Z23 fallout MALINDI fallout Z9A fallout Total downrange = ~32800 km Mobile station 120 km entry interface point RE-ENTRY DESCENT Recovery ship Re-entry & descent = ~7700 km 25,7 km 4 5 Downrange 3 [Altitude scale: 10X] 4 Reference Timeline 1 Lift off T = 0 [s] 2 Separation T = 966 [s] 3 Entry gate T = 3857 [s] 4 Descent gate T = 5180 [s] 5 Splashdown T = 6061 [s] Ascent segment Orbital segment Re-entry segment Descent segment 966 [s] 2891 [s] 1323 [s] 881 [s]

4 TPS Architecture The TPS&HS S/S consists of the following assemblies: Nose Assembly (developed by Herakles) Windward Assembly (developed by Herakles) Body Flap Assembly (developed by MT Aerospace) Leeward, Lateral and Base Assemblies (developed by AVIO) All the interfaces between different TPS&HS assemblies and between TPS&HS assemblies and different IXV sub-systems are designed and developed by Thales Alenia Space 4

5 Nose Assembly The Nose Assembly HS consists of a Nose Cap made of HKS Sepcarbinox L6 CMC material filled with internal insulation (Zircar AB, Pyrogel) held in place by an Aluminum Nose Dome The Nose Assembly is linked to an Aluminum Ring that transmits all loads from the Nose and the Dome via the attachment brackets to the bulkhead 5

6 Nose Assembly 6

7 Windward Assembly The Windward C/SiC Assembly is characterized by the innovative shingle technology, which is able to dissociate mechanical and thermal insulation functions Each shingle is composed of CMC panel with peripheral stiffeners and internal stiffeners; attachment system, ceramic fiber internal insulation stack-up (Zircar AB, Aeroguard, Pyrogel) and ceramic fiber seal (Zircar AB enveloped by Nextel) are placed around the peripheral stiffeners of the C/SiC panel 7

8 Ablative TPS Assembly The Ablative TPS consists of different materials, each fulfilling a dedicated function: an external insulating material providing the heat absorption and removal by means of thermo-ablative phenomena: P50 cork on the majority of the IXV surface and a silicone elastomer based material SV2-A on antennas an antistatic paint coating on the external ablative surface, avoiding electrostatic charge accumulation and providing known thermo-optical properties to the outer insulator surface, as well as avoiding moisture absorption an adhesive layer that provides the bonding of the insulating material on IXV cold structure (EA9394 for P50, siliconic adhesive for SV2-A) a filler (based on EA9394 and P50 for P50, siliconic for SV2-A) that provides a continuum insulating mean in correspondence of gaps present between the insulating material tiles 8

9 Body Flap Assembly The Body Flap Assembly (Keraman ), designed to contribute to aerodynamics and manoeuvrability of IXV, comprises the following main constituents: a pair of control surfaces a rod-like to deflect the flap for flight control ceramic bearings installed at the attachment points flexible Nextel-Saffil hinge seals Hinge TPS forming the TPS interface between the Body Flap and the TPS elements Electro-Mechanical Actuator (EMA) TPS, that provides the interface with bulkhead, hinge TPS and flap rod 9

10 Body Flap Assembly 10

11 TPS Assemblies Interfaces Each single TPS assembly is designed to properly interface with the vehicle cold structure, the adjacent TPS assemblies, the launcher adapter, the inflight experimentation sensors and the MGSE Examples of adjacent TPS I/Fs are shown in the following figures 11 Ablative Nose Skin Ablative Cold structure Cold Structure Seal Hinge TPS seal Seal Hinge TPS skin Leeward ablative TPS / Nose Interface Lateral ablative TPS / Hinge TPS

12 Development Tests Nose and Windward Assembly CMC samples: CMC characterization: mechanical tests (tensile, compression, shear), thermal properties (thermal diffusivity, thermal expansion, specific heat) CMC oxidation (in VKI Plasmatron) CMC catalycity (in VKI Plasmatron) CMC behaviour in sea environment Insulation: thermal properties and modal characterization Attachments: mechanical strength on nose and shingle attachments static test on shingle attachments: compressive and shear test on ceramic washers, tensile test on screws, static/buckling test on complete attachment fatigue test on shingle attachments mechanical test on nose attachments thermal characterization 12

13 Development Tests Nose and Windward Assembly (cont d) Singularities: mechanical strength, dynamic and thermal test on pressure port Seal: permeability venting sneak-flow Assembly test: verification of components mountability/dismountability 13

14 Development Tests Ablative TPS SV2A 14

15 Development Tests Ablative TPS P50 15 Thermo-physical tests: specific heat, enthalpy of formation (for both virgin and charred material), thermal conductivity, TGA, mass spectrometry, CTE Mechanical characterization: ultimate elongation, Young modulus, hardness, density, ultimate pull and shear strength, peeling Interface bonding shear tests Humidity tests Ageing tests Outgassing tests Torch tests Technological tests: full scale application (22 mm) Thermo-ablative tests (in VKI Plasmatron)

16 Development Tests Body Flaps Assembly 16 Considering the sufficient high TRL ( 5) of the Body Flap reached during X- 38 and EXPERT Programs, no development tests were performed in phase C2; the same applies to Hinge TPS For EMA TPS, the increase of the development status by means of ground tests has been considered unfeasible and therefore the development has been carried out only by analysis Catalycity and emissivity tests have been carried out on Keraman samples at VKI

17 Assembly Qualification Tests 17 PWT test with singularities in Scirocco Thermo-mechanical test Dynamic test Shock, sine and random tests [performed] Manufacturing, integration and verification test (full scale validation test) Thermal and thermo-mechanical behaviour verified through TPS&HS S/S PWT test in Scirocco Body Flap + EMA TPS dynamic test [performed] EMA TPS thermal test [performed] Hinge TPS dynamic test [performed] Body Flap + Hinge TPS pressure testing

18 Assembly Qualification: Ablative TPS Shock, Sine & Random Tests 18 Configuration for sinusoidal and random tests Configuration for shock test

19 Assembly Qualification: Ablative TPS Full Scale Validation Tests P50 bonding process with vacuum bag already qualified in the frame of Vega program Different bonding strategies tested: vacuum bag, bladder, weights, adhesive tape Additional tests objectives SV2-A bonding qualification mortar cap bonding unglued area Bonding strength evaluated by means of pull test 19 PARTIALLY UNGLUED TILE SV2-A TILE MORTAR CAP GLUING TEST

20 Assembly Qualification: Body Flap Assembly Dynamic Test MT-Aerospace performed Body Flap+EMA TPS qualification tests 20 Vibration test at IABG (1/2012) Shock test at IABG (11/2012)

21 S/S PWT Test Design Interface Verification PWT tests at TPS&HS S/S level are planned in CIRA Scirocco facility to verify in hot conditions the design of the interfaces between the adjacent TPS assemblies in terms of capability to comply with the requirements relevant to sneak-flow (overheating) and step&gap 21 Nose Leeward Ablative Shingle Windward Assembly Hinge TPS

22 System Qualification Tests Body Flap Assembly Chain A joint test to verify the complete Flaps Control System, i.e. the combined EMA / Body Flap Assembly performances, will be performed aim of the test is to validate and calibrate the multi-body model of the Body Flap Chain, and to run a final set of cases to predict the Body Flap Chain behaviour during flight Ablative tests Ablative TPS tiles are made available by AVIO and implemented into the IXV test model to be utilized for the following tests: DRS drop test In Flight Experimentation tests Antenna + Fiberglass + Ablative TPS compatibility test Full-scale bridle extraction test 22