Ultra-High Temperature Ceramic Additively Manufactured

High Intensity Thermal Exchange through Materials and Manufacturing Processes (HITEMMP)

Annual Program Review Meeting

October 21 & 22 – WebEx

Ultra-High Temperature Ceramic Additively Manufactured Compact Heat Exchangers

(UHT-CAMANCHE)

David W. Lipke, Missouri University of Science and Technology

Project Vision

Extreme Environments. Extreme Materials. Extreme Performance.

Brief Project OverviewFed. funding: $1.8M

Length 36 mo.

DavenportMa

Held

Jape

Leu Lipke

Hilmas

Watts

Fahrenholtz

Park

Team member Location Primary role(s) in project

Missouri S&T Rolla, MO Materials, manufacturing

NREL Golden, CO HX modeling, T2M

Echogen Akron, OH sCO2 design/test consulting

Team Profile

‣ 60+ years professional experience in ceramic engineering

‣ 30+ years professional experience with supercritical CO2 technologies and power cycle development

Project Inception

‣ Convergence of materials (UHTCs), manufacturing technologies (additive manufacturing, ceramic welding), and application (supercritical CO2 power cycles)

Heat Exchanger Design – Key Conceptual Features

2

‣ Counterflow microchannel type

‣ 44x44 array of 0.5mm channels at 2.0mm center-to-center distance

‣ Additively manufactured HX

‣ Graded ceramic-to-metal headers

‣ Pressurized shell

Heat Exchanger Design Details – Performance Metrics

3

Units Hot Side Cold Side

Fluid CO2 CO2

Mass flow rate kg s-1 0.1 0.1

Inlet temperature °C 1100 300

Outlet temperature °C 699 700

Inlet pressure MPa 8 25

Outlet pressure MPa 7.79 24.96

Pressure drop MPa (%) 0.01 (0.03) 0.04 (0.51)

Number of channels 1000 1000

Heat transfer area m2 0.08 0.08

Channel diameter μm 500 500

Surface roughness μm 50 50

Average Pr 0.71 0.79

Average Re 5580 6960

Average Nu 20.4 25.2

Units Values

UA kW °C-1 0.129

LMTD °C 399.1

Effectiveness % 50.2

Q kW 51.5

HX Metrics

core

only

with

headers

Compactness m2 m-3 349 131

Power

density

(volume) MW m-3 153 83

(mass) kW kg-1 25 13

Length cm 5.2 10.8

Width cm 6.7 4.5

Volume cm3 338 622

Mass kg 2.0 4.0

Heat Exchanger Performance Analysis

4

Computational domain of a reduced cell of the heat

exchanger selected for analysis

CFD FEA Initial and refined mesh

‣ Verified mesh convergence and validated CFD/FEA multi-physics heat transfer model

Plane 1

Plane 2

Plane 3

Plane 4

Plane 1 Plane 2

Plane 3 Plane 4

°C

Heat Exchanger Performance Analysis

5

‣ Predicted HX thermal performance (reduced cell model)

‣ Solid thermal conductivity is high (> 50 W m-1 K-1)

‣ Heat transfer is convection limited

‣ Negligible transverse temperature differences

Heat Exchanger Performance Analysis‣ Coupled thermal-mechanical analysis:

6

‣ von Mises stress with hydrostatic compression:

‣ Future modeling work:

– Manufacturing defects

– Manifold optimization for thermal stress and flow maldistribution

Material Selection: ZrB2 + 30% SiC

7

‣ Ultra-high temperature ceramic (Tm.p. > 3000°C)

‣ Various additives improve sintering, oxidation, creep, and toughness

‣ TRL 4-6 depending on application

Neuman EW, Hilmas GE, Fahrenholtz WG.

Mechanical behavior of zirconium diboride-

silicon carbide-boron carbide ceramics up to

2200°C. J. Euro. Ceram. Soc. 2015;35(2):463-

476.

Zimmermann JW, Hilmas GE, Fahrenholtz

WG, Dinwiddie RB, Porter WD, Wang H.

Thermophysical Properties of ZrB2 and ZrB2-

SiC Ceramics. J. Am. Ceram. Soc.

2008;91(5):1405-1411.

Material Compatibility Screening Study

8

0.0%

0.5%

1.0%

1.5%

2.0%

2.5%

3.0%

3.5%

4.0%

4.5%

5.0%

0 100 200 300 400 500

Rela

tive N

et

Change in

Specific

Weig

ht

Time (min.)

TGA Screening (1100°C, 1 bar, 100 mL/min. CO2)

60-40 SiC-ZrB2

50-50 SiC-ZrB2

30-70 SiC-ZrB2

0-100 SiC-ZrB2

Target Metric

k'' ≈ 6.0x10-8 g2 m-4 s-1

Oxidation time: 40,000 hours

Allowable recession:10 microns (guess)

𝑘𝑐 = Τ𝑥2 2𝑡𝑘𝑐: Parabolic rate constant (recession)

𝑘′′ = 𝑘𝑐 ∙ 2 Τ𝑀𝑂ത𝑉𝑍𝑂

2

𝑘′′: Parabolic rate constant (specific weight change)ത𝑉: Equiv. scale vol. 𝑀𝑂: At. mass O𝑍𝑂: Valence O

40% ZrB2 + 60% SiC

50% ZrB2 + 50% SiC

70% ZrB2 + 30% SiC

100% ZrB2 + 0% SiC

Composition (vol. %)

Manufacturing Process Flow Diagram

10

QC and Performance Testing

Defect detection Proof testing

Packaging

Ceramic welding Shell integration

Pressureless Sintering

Additive Manufacturing

Ceramic On-Demand Extrusion Controlled drying and debinding

Materials Preparation

Additives selection Mixing and milling Paste formulation

Attrition Mill Thinky Mixer Thinky Syringe Charger

Paste rheology


11



Packaging







Additive Manufacturing (ZrB2 + 30 vol. % SiC)‣ Preliminary test prints

12

Test Bar2x2 array0.5 mm channel diameter1.0 mm wall thickness50 mm length


13



Packaging







Hadron Technologies HT-12MF1-SV

Thermal Technology graphite furnaces

2.45 GHz, 12 kW


14



Packaging







TIG

Hilmas GE, Fahrenholtz WG, Watts JL,

Brown-Shaklee HJ. Ceramic welds,

and a method for producing the

same. Patent No. US8715803 (2014).

a

d

b c


15



Packaging







Zeiss Xradia X-ray Microscope


16



Packaging







50 mm

5 mm

4x mag high-res sub-volume centered on

printed channel

45 mm

4.6 mm

Green body (as-printed)

After sintering at 2000°C (94% theoretical density)

X-ray Microscopy

Planned sCO2 Test Loop @ S&T

17

Heater 2

Heater 1Recuperator

ACC or WCC

CO2cylinder

with heater

Back-pressureregulator

Pump

WCC

Pressure-reducingregulator

WCC

P (MPa) | T (°C)

6.9 | 28

6.9 | 25

26.0 | 53

25.1 | 53 25.0 | 300 24.9 | 464

8.2 | 449

8.0 | 650

7.8 | 479

7.7 | 50

2.0 kW

1.2 kW

-2.6 kW

0.0

05

kg/

s

6.9 | 45

-0.9 kW0.15 kW

‣ Continuous flow loop, single metered flow, 2 kW thermal

‣ 8 MPa, 650°C on low-pressure side, 25 MPa on high-pressure side

‣ Liquid pumping loop based on footprint, budget (ca. $100k) and lab safety (ventilation) considerations

‣ Used for HX sub-scale testing, sCO2 materials compatibility studies, and proof/shakedown testing

Technology-to-Market Updates‣ Commercialization planning

– IP generation for disruptive materials and manufacturing technologies

• Applications outreach for extreme environment components

– Ceramic HX (via startup or contract manufacturing) – low commercial readiness level

• Requires identification of first markets with demonstrable near-term demand

• Requires de-risking of ceramics for critical or long duration applications:

– Materials database generation is costly (labor and time intensive)

– Must be preceded by scale-up to relevant scale of production, automation, etc.

• Cost model: baseline set by cost center approach using federally approved guidelines

– First prototype: $5730 ($45,000/UA)

» 20x cost reduction required (labor costs appear to be a driving factor) 18

Which comes first, the HX or

the application?

– Target at production scale: $260 ($2,000/UA)

Like

liho

od

Almost Certain

Likely

Moderate

Unlikely

Rare

Insignificant Minor Moderate Major Catastrophic

Consequences

Risk Update

Risk #

Ceramic AM properties 1

Ceramic welding 2

Materials compatibility 3

HX design (thermal stress) 4

Reliability 5

Cost-performance TEA 6

5 4

3

2 16

X

X

Now

Start of project

12 3

4

5

6

Progress Against Tasks – Timetable‣ Accomplishments:

– HX conceptual design shown to be viable (validated CFD/FEA model)

– Preliminary screening identifies compatible material for sCO2 operation

– Custom, dedicated ceramic AM machine built (still undergoing testing)

‣ What remains to be done?

– Material and manufacturing process optimization (40-50 weeks)

– Detailed HX design of flow headers and connections to sCO2 test loop (20-25 weeks)

– Procurement and commissioning of sCO2 test loop @ S&T (20-25 weeks)

‣ Primary challenges:

– COVID-19 disruptions to lab access and personnel recruitment

20

Potential Partnerships

‣ sCO2 test loop @ S&T can be made available to program teams starting mid-late 2021

‣ Project needs:

– Industry connections to assess case for need to further increase turbine inlet temperature and first downstream component (recuperator), as well as likelihood of ceramic HX technology adoption

– Consult with current generation sCO2 HX manufacturers regarding design solutions for robust (mechanically compliant) process connections at 700°C and 25 Mpa – avoid reinvention

‣ Anticipated needs beyond project period to successfully commercialize UHTC-based HX:

– First market application scenario to set specifications for HX scale and operating conditions

– Follow-on support for manufacturing technology improvements to support increased feature complexity, production scale-up, and materials database generation

22

https://arpa-e.energy.gov

Q&A

[email protected]

http://www.arpa-e.energy.gov/

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Ultra-High Temperature Ceramic Additively Manufactured