Thermomechanical behavior of refractory masonry linings An overview

Thermo-mechanical behavior of refractory masonry linings: An overview on numerical simulation Paulo B. Lourenço, João M. Pereira, Pratik Gajjar University of Minho, Portugal

Presentation Outline § Background § Numerical simulations of a steel ladle § Preliminary simulations of tests § Conclusions and Recommendations

Refractory § Heat-resistant material, i. e. a mineral resistant to decomposition by heat, pressure and chemical attack, that retains strength and form at high temperatures (600 to 1600ºC / 1000 to 3000º F) with density 2 to 3 § Typically linings of vessels to contain and process fluids at high temperatures, e. g. glass or steel Bricks Castables

Refractory (Materials) § Alumina Spinel § Silica § Magnesia-Chromite § Zirconia § Bauxite § Vermiculite

Refractory (use) § Used as linings in, § Furnaces § Kilns § Incinerators § Reactors § Iron and steel industry is major consumer of Refractories (about 70%) Steel Ladle (TATA Steel)

Refractory (Loads) § Mechanical loads, primarily from self weight and service condition which are normally low in intensity § Thermal loads arising from service conditions § Thermal shock and impact loading § Plastic deformation (creep) at high temperature § Corrosion at high temperature

Refractory (Behavior) (Prietl, 2006)

Refractory (Behavior)

Refractory (Behavior)

Refractory (Behavior)

ATHOR A Marie Skłodowska-Curie Action European Training network § Thermomechanical behaviour of refractory linings in Iron and Steel applications. § impact of corrosion on thermomechanical properties § thermal shock resistance § modelling of nonlinear thermomechanical behaviours § instrumentation of industrial devices § measurement in operation conditions. § 7 Academic and 8 industrial partners

ATHOR University of Minho, Portugal § Development of numerical models considering elastoviscoplasticity, damage, corrosion effects and joints. § Thermomechanical testing on masonry subsystems ladle. § Measurements for numerical validation.

Simulation of a partial ring model § To investigate the effect of refractostatic pressure on the steel shell of an industrial ladle. Wear lining Permanent lining Steel Shell Steel ladle shell (TATA Steel)

Simulation of Partial Ring model § Kinematic hardening model for wear lining § Nonlinear thermal properties for all layers § Elastic mechanical properties for effective permanent and steel shell § Modeling of dry joints between the bricks and layers 0. 2 mm Gap 3 mm Gap

Simulation of Partial Ring model § Initial temperature of 20 ᵒC § Steel shell is exposed to a constant temperature of 20 ᵒC § Heating in 20 hours to 1050 ᵒC § Dwelling for 2 hours at 1050 ᵒC § 2. 5 hours full-time with liquid steel of 1600 ᵒC

Simulation of Partial Ring model Temperature distribution at 22. 5 hours (ᵒC)

Simulation of Partial Ring model Tangential compressive stresses (Pa)

Simulation of Partial Ring model Radial stresses (Pa)

Simulation of Partial Ring model Tangential elongation (-)

Simulation of a real wall § Difficulties in modeling due to limited data of the temperature dependent properties § For the geometry, a 2 D or 3 D model can be used, depending on the boundary conditions § Numerical model can be micro or homogenized, however, homogenization might lead to reduced accuracy § Time-temperature relation can be from standard codes or can be applied according to its application of refractory

Approach § 3 D model with magnesia-chromite bricks and dry joints. § Dimensions of wall panel 550(L) × 84(B) × 480 (H) mm. 480 § Brick unit dimensions 110 × 84 × 48 mm. 84 84 550 48 110

Approach § Initial temperature of 25ᵒC § Transient temperature similar to EN 1991 -1 -2 § Duration of fire: 2. 5 hours § Pre-compression of 2. 5 MPa at top of wall panel § Rigid support at bottom of wall panel

Results Nonlinear heat transfer analysis. Nonlinear mechanical analysis. Mechanical analysis derives stress and strain from heat transfer analysis.

Results (Temperature Distribution) Temperature evolution (inside and outside).

Results (Out-of-plane displacement) Out-of-plane displacement for the center point of wall.

Conclusions and Recommendations § A new world for masonry § An example of steel ladle shows that the proposed usage will not induce damage § An example of replication of an experiment was shown. § It is possible to observe the development of stresses and damage under the transient temperature loading § Evolution of these stresses and damages agree reasonably well with experiments § Further experimental data seems to be needed

Acknowledgements This work was supported by the funding scheme of the European Commission, Marie Skłodowska-Curie Actions Innovative Training Networks in the framework of the project ATHOR - Advanced THermo -mechanical multiscale modelling of Refractory linings – 764987 Grant. This mission was supported by the

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