Hypersonic Wind Tunnels for Meteorite Treatmentusers.ba.cnr.it/imip/cscpal38/HYMEP/lectures/Paganucci.pdf · University of Pisa, Pisa, Italy SITAEL S.p.A., Pisa, Italy Presented by:

University of Pisa, Pisa, Italy

SITAEL S.p.A., Pisa, Italy

Presented by: Fabrizio Paganucci

Hypersonic Wind Tunnels for Meteorite Treatment

HyMEP 2017 Erice, Italy, October2017

Department of Civil and Industrial Engineering, Aerospace Engineering Section, University of Pisa

2/15 Hypersonic Wind Tunnels for Meteorite Treatment 2/25 Hypersonic Wind Tunnels for Meteorite Treatment

Outline

The hypersonic wind tunnel HEAT Description Performance Main experimental activities The use of HEAT for experiments on micrometeoroids (D: 300 mm – 1 mm)

Experiment framework Experiment setup and running Results and analysis New developments The air-fed HT5k as Particle Flow Generator

3/15 Hypersonic Wind Tunnels for Meteorite Treatment 3/25

The High-Enthalpy Arc-heated Tunnel (HEAT) - Layout

The vacuum chamber

The gas generator

The expansion nozzle


HEAT - Performance


HEAT- Features

• Inexpensive, both in realisation and operation. • Flexible, useful for a large variety of different studies in different flow conditions. • Safe and reliable, to allow for operation in a small laboratory by untrained personnel and/or

students.

• Relatively long test times (up to ~500 ms). • Capability of independently setting both stagnation pressure (up to 17 bar) and enthalpy (up to 6

MJ/kg). • Tests can be easily performed with different gases by simply switching the feed lines.

• Uncooled design, reduced materials and probes survivability problems, simplified model design. • Feasibility of installing mixing/shielding screens, reducing cross-stream gradients. • Need for lower pumping rates (the dump chamber acting as a buffer).

• Quasi-steady operation eliminates problems arising from variation of stagnation conditions. • Shorter fluid residence time in the electrodes region reduces flow contamination.

• Spotty, unstable arc operation may generate electromagnetic noise. • Stagnation conditions are inherently less stable than in shock-driven tunnels. • Flow contamination is unavoidable (estimated: tungsten 65~250 ppm, copper ~1 ppm).


3.5 4 4.5 5 5.5 6 6.5-40

-30

-20

-10

0

10

20

30

40

Mach number

Radial position (mm)

DiameterOff diameter

L. Biagioni, F. Scortecci, F. Paganucci, L. D. Nill, Experimental Characterization for Hypersonic Testing, AIAA-1998-3131, 34th Joint Propulsion Conference, Cleveland (OH), July 1998.

HEAT- Flow Characterization

five-hole probe

temperature probe

Hot flow (1800 K) Cold flow

3.5 4 4.5 5 5.5 6 6.5-40

-30

-20

-10

0

10

20

30

40

Mach number

Radial position (mm)

Diameter


Constant Unit Reynolds No. Lines in the Pressure-Enthalpy Plane

Test section Mach number: 6 (solid lines) and 12 (dotted lines)

HEAT- Performance Envelopes

M-Re-Kn envelope

for D=10-4 ÷ 10-3 m

for D=10-3 ÷ 10-2 m


flow

HEAT- SWBLI Experiment

F. Scortecci, F. Paganucci, L. d’Agostino, “Experimental Investigation of Shock-Wave/Boundary-Layer Interactions over an Artificially Heated Model in Hypersonic Flow”, AIAA-98-1571, 8th International Space Planes and Hypersonic Systems and Technologies Conference, Norfolk (VA), April 1998.


HEAT- SWBLI Experiment

0

0.05

0.1

0.15

0.2

0.25

35 40 45 50 55 60 65 70 75 80 85 90

Distance from leading edge [mm]

Cp

Num 300K

Num 400K

Num 500K

Exp 300K

Exp 400K

Exp 500K

0

0.001

0.002

0.003

0.004

0.005

0.006

37.5 42.5 47.5 52.5 57.5 62.5 67.5 72.5 77.5

Distance from leading edge [mm]

St

Num 300K

Num 400K

Num 500K

Exp 300K

Exp 400K

Exp 500K

15 degrees ramp, 1800 K


HEAT- A Selection of Other Activities

A. Cristofolini, et al., Magnetohydrodynamics Interaction Over an Axisymmetric Body in a Hypersonic Flow, Journal of Spacecraft and Rockets, Vol. 45, No. 3 (2008).

Magneto-Hydro-Dynamics Interaction in Hyperonic Flow

Q. Liu, A. Passaro, D. Baccarella, and H. Do, Ethylene Flame Dynamics and Inlet Unstart in a Model Scramjet, Journal of Propulsion and Power, Vol. 30, No. 6 (2014), pp. 1577-1585.

Tests on Scramjet Propulsion

In collaboration with the Dept. of Aerospace and Mechanical Engineering, University of Notre Dame, IN

An hypersonic facility similar to HEAT has been built and delivered to the University of Notre Dame


Tests on micrometeoroids (D: 300 mm – 1 mm) (2012)

Objective

To assess the feasibility of laboratory simulations of micrometeoroid entry in atmosphere to assess their alteration mechanisms (melting, evaporation, sputtering, etc.) Partecipants Dipartimento di Fisica, Università di Pisa, (Stephen N. Shore) Dipartimento di Fisica, Università di Firenze, (Emanuele Pace) Dipartimento di Scienza della Terra, Università di Pisa, (Luigi Folco, Massimo D’Orazio) Alta SpA (now Sitael SpA), (Andrea Passaro) Tests on Jan 2012: 3+1 samples

Test on Nov 2012: 11 samples (pure materials)

Type Stony cosmic spherule Barred Olivine (BO)

Shape Spheroidal

Dimension 300-500 mm

Composition Olivine, glass, iron oxide

Tmelting @ 1 bar 1604 °C


Tests in Jan 2012 – Experimental setup and runs

• Nozzle: M 4.5 +/- 0.05;

• Spherules glued on needles with a zirconia based adhesive;

• Working fluid: synthetic air (20% O2; 80%N2);

• Running time: 350 ms

• Mean total enthalpy: 2.5 MJ/kg

• Thermal flux: 1.3x107 W/m2

• Mean total temperature: 2400 K


Tests in Jan 2012– Result and analysis

Optical observations

• First run: 3 spherule samples (2 not usable for needle or glue failure);

• Second run: 1 spherule sample + 1 adhesive sample (both lost);

F. Savini, Simulazione in laboratorio dell’entrata e sopravvivenza dei micrometeoroidi nell’atmosfera terrestre, Tesi di Laurea in Fisica, Università di Pisa, AA 2011-12


Tests in Jan 2012 – SEM analysis

(Secondary Electrons 100x) (Back Scattered Electrons 100x)

(800x) (2000x)

• The sample has lost mass (estimated about 65% the initial mass);

• Dendritic crystals observed on the glass matrix;

• Similar dendritic crystals made of iron oxide (Magnetite) normally observed on natural micrometeorites;

Magnetite dendritic crystals on a natural micrometeorite


Tests in Jan 2012– Spectrometric analysis

X-ray Diffraction Spectroscopy (exposition time: 300 min)

Energy Dispersive Spectroscopy

• The sample surface in the various parts has a chemical composition similar to natural micrometeorites (Savini 2012);

• Contaminations of zirconium (from the adhesive) and copper (from HEAT electrodes);

Spherule diffraction spectrum compared with spectra from database indicates:

• Presence of zirconia(ZrO4) (adhesive);

• Presence of iron oxides: Magnetite (Fe2+Fe3+

2O4) , Magnesium Ferrite ((FeMg)2+Fe3+

2O4), traces of Cromite (Fe2+Cr+

2O4).


Tests in Jan 2012– Raman Spectroscopy

1

2

Raman spectroscopy has confirmed the dendritic crystals are made of Magnetite.


Tests in Nov 2012

11 specimens made of pure materials

• Sample fixing improved;

• Three runs performed.

A. Passaro, Rientro micrometeoriti – Analisi semplificata del riscadamento in HEAT, Alta MME TN01, 2012


Tests in Nov 2012 – Runs and results

No sample failures (!) Melting conditions not reached (specimens too large and hot test time too short (max 710 ms)) Numerical simulations have indicated a hot test time of at least 1 s is necessary (Passaro 2012)


A result discussion is proposed on the basis of the work: G. Briani, E. Pace, S. N. Shore, G. Pupillo, A. Passaro, S. Aiello, Simulations of micrometeoroid interactions with the Earth atmosphere, Astronomy &Astrophysics, 552, A3, (2013). Equation of motion: Equation of energy:

Where:

Tests in Jan 2012– Result discussion

(G=1)





Entry condition HEAT Experiment

Thermal flux (W/m2) 106 107

Exposition time (s) 5 0.35

Overall thermal energy (J/m2) 5x106 3.5x106


Tests in Jan 2012– Concluding remarks

• Although the fluid dynamic regimes are very different , the overall thermal energy both during test and entry conditions seems to be of the same order of magnitude;

• The sample has reached melting temperature;

• Sample mass loss is in line with what observed in natural micrometeorites;

• The formation of dendritic crystals made of magnetite on the sample surface is observed as in natural micrometorites;

• HEAT facility seems adequate to simulate the entry of 300-500 mm micrometeoroids;

• For larger micrometeoroids, longer (> 1 s) running time seems to be necessary.


Sitael Particle Flow Generator

T. Andreussi, et al, Development and Experimental Validation of a Hall Effect Thruster RAM-EP Concept , IEPC-2017-377, 35th International Electric Propulsion Conference, Atlanta, Georgia, USA, October 8 – 12, 2017

Particle Flow Generator (PFG) developed to test an air-breathing electric thruster (RAM-HET);

RAM-HET operates at low or very low Earth orbit (150-200 km);

Working fluid is air collected by an air intake;

PFG produces an air flow simulating flight condition to test RAM-HET in laboratory;

PFG is a modified air-fed 5kW Hall Effect Thruster (HT5k).

HT5k operating with air RAM-HET prototype


Property Unit Flight Scenario Tested Setup

Inlet Number Density m-3 1.49 · 1016 7.25 · 1016

Inlet Mass Density kg·m-3 5.47 · 10-10 2.66 · 10-9

Average Flow Velocity km·s-1 7.80 9.12

Mean Molecular Mass a.m.u. 22.1 22.1

FPG as a wind tunnel for meteoroid experiments

Drag balance and Patterson probe for PFG flow calibration

Different flow conditions (in terms of velocity and air density) obtained by changing PFG operation parameters and the distance between PFG and RAM-HET inlet;

The same could be done for meteoroid experiments.

Flow conditions at 500 mm from PFG (close to 200 km flight scenario)

HT5k operating as PFG

Anode Mass Flow Rate 5 mg/s (air)

Discharge Voltage 300 V

Discharge Current 8 A

Discharge Power 2.4 kW


Thank you and who made the work:

HEAT facility: Andrea Passaro, et al. Micro meteoroid experiments: Andrea Passaro, Stephen N. Shore, Emanuele Pace, Luigi Folco, Massimo D’Orazio Particle Flow Generator: Tommaso Andreussi, Gianluca Cifali, Vittorio Giannetti, Antonio Piragino, Eugenio Ferrato

Documents

Hypersonic Wind Tunnels for Meteorite Treatmentusers.ba.cnr.it/imip/cscpal38/HYMEP/lectures/Paganucci.pdf · University of Pisa, Pisa, Italy SITAEL S.p.A., Pisa, Italy Presented by: