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The Temperature Field Effect on Dynamic Stability Response of Three-layered Annular Plates for Different Ratios of Imperfection Cover

The Temperature Field Effect on Dynamic Stability Response of Three-layered Annular Plates for Different Ratios of Imperfection

By: Dorota Pawlus  
Open Access
|Apr 2023

Figures & Tables

Figure 1

Scheme of thermomechanical loading of a three-layered annular plate built of outer layers 1 and 3 and middle layer 2.
Scheme of thermomechanical loading of a three-layered annular plate built of outer layers 1 and 3 and middle layer 2.

Figure 2

Deflections of the axisymmetrical m = 0 plate model versus imperfection ratio ξ2 under a temperature field with a positive gradient and two rates a = 200 K/s and a = 800 K/s.
Deflections of the axisymmetrical m = 0 plate model versus imperfection ratio ξ2 under a temperature field with a positive gradient and two rates a = 200 K/s and a = 800 K/s.

Figure 3

Deflections of the asymmetrical m = 7 plate model versus the imperfection ratio ξ2 under a temperature field with a positive gradient and two rates a = 200 K/s and a = 800 K/s.
Deflections of the asymmetrical m = 7 plate model versus the imperfection ratio ξ2 under a temperature field with a positive gradient and two rates a = 200 K/s and a = 800 K/s.

Figure 4

Time histories of deflections and velocity of deflection for plate model m = 0 with the imperfection ratio ξ2 = 2 loaded thermally with a positive temperature gradient, with rate a = 200 K/s: a) FDM model, b) FEM model with critical deflection form.
Time histories of deflections and velocity of deflection for plate model m = 0 with the imperfection ratio ξ2 = 2 loaded thermally with a positive temperature gradient, with rate a = 200 K/s: a) FDM model, b) FEM model with critical deflection form.

Figure 5

Deflections of the asymmetrical m = 7 plate model with different imperfection ratios ξ2 under mechanical load and thermal load with a positive temperature gradient and various rates a.
Deflections of the asymmetrical m = 7 plate model with different imperfection ratios ξ2 under mechanical load and thermal load with a positive temperature gradient and various rates a.

Figure 6

Time histories of deflections for the FDM plate with ξ2 = 2 thermomechanically loaded with various rates a or fixed temperature ΔT = 800 K: a) axisymmetrical plate mode m = 0 and b) asymmetrical plate mode m = 7.
Time histories of deflections for the FDM plate with ξ2 = 2 thermomechanically loaded with various rates a or fixed temperature ΔT = 800 K: a) axisymmetrical plate mode m = 0 and b) asymmetrical plate mode m = 7.

Figure 7

Deflections of a) axisymmetrical plate mode m = 0 [11], b) asymmetrical plate mode m = 7 versus negative and positive imperfection ratios ξ2 under mechanical load and thermal load with a negative gradient.
Deflections of a) axisymmetrical plate mode m = 0 [11], b) asymmetrical plate mode m = 7 versus negative and positive imperfection ratios ξ2 under mechanical load and thermal load with a negative gradient.

Figure 8

Time histories of deflections and velocity of deflections for the axisymmetrical m = 0 FEM plate model thermomechanically loaded with a positive temperature gradient versus different imperfection ratios ξ2 and temperature growth loads a: a) ξ2 = 1, a = 200 K/s, b) ξ2 = 1, a = 800 K/s, c) ξ2 = 2, a = 200 K/s, d) ξ2 = 2, a = 800 K/s.
Time histories of deflections and velocity of deflections for the axisymmetrical m = 0 FEM plate model thermomechanically loaded with a positive temperature gradient versus different imperfection ratios ξ2 and temperature growth loads a: a) ξ2 = 1, a = 200 K/s, b) ξ2 = 1, a = 800 K/s, c) ξ2 = 2, a = 200 K/s, d) ξ2 = 2, a = 800 K/s.

Figure 9

Time histories of deflections and velocity of deflections for a) FDM plate model and b) FEM plate model m = 0, ξ2 = 1 loaded mechanically and thermally with a positive temperature gradient and rate a = 200 K/s.
Time histories of deflections and velocity of deflections for a) FDM plate model and b) FEM plate model m = 0, ξ2 = 1 loaded mechanically and thermally with a positive temperature gradient and rate a = 200 K/s.

Figure 10

Deflections of the FDM plate model ξ2 = 1 loaded thermally with a positive temperature gradient and rate a = 200 K/s versus calibrating number ξ1.
Deflections of the FDM plate model ξ2 = 1 loaded thermally with a positive temperature gradient and rate a = 200 K/s versus calibrating number ξ1.

Figure 11

Deflections of the FDM plate model ξ2 = 1 loaded thermomechanically with a positive temperature gradient and rate a = 200 K/s versus a) different values of calibrating number ξ1 and b) value of calibrating number ξ1 = 5 for axisymmetrical plate m = 0.
Deflections of the FDM plate model ξ2 = 1 loaded thermomechanically with a positive temperature gradient and rate a = 200 K/s versus a) different values of calibrating number ξ1 and b) value of calibrating number ξ1 = 5 for axisymmetrical plate m = 0.

Figure 12

Deflections of the FDM waved m = 7 plate model loaded thermally with a positive temperature gradient and rate a = 200 K/s for mixed values of imperfection ratios: a) only positive, b) positive and negative.
Deflections of the FDM waved m = 7 plate model loaded thermally with a positive temperature gradient and rate a = 200 K/s for mixed values of imperfection ratios: a) only positive, b) positive and negative.

Figure 13

Influence of imperfection ratios on the distribution of the FDM waved m = 7 plate model deflections in a radial direction caused by thermal loading with a positive temperature gradient and rate a = 200 K/s.
Influence of imperfection ratios on the distribution of the FDM waved m = 7 plate model deflections in a radial direction caused by thermal loading with a positive temperature gradient and rate a = 200 K/s.

Values of critical dynamic mechanical loads pcrdyn and corresponding temperature differences ΔTb for the axisymmetrical m = 0 FDM plate model thermomechanically loaded and imperfected with ratio ξ2 = 2_

a (K/s)ΔT (K)pcrdyn (MPa)/DTb (K)

ξ2 = 2

Positive gradientNegative gradient
035.8/035.8/0
20034.47/7.437.26/8.0
80027.12/23.242.39/36.4
ΔT = 80022.36/19.244.25/38.0

Values of critical temperature differences ΔTcrdyn for the axisymmetrical m = 0 FDM plate model versus the imperfection ratio ξ2 under a temperature field with a positive gradient and two rates a = 200 K/s and a = 800 K/s_

Rate a (K/s)ΔTcrdyn (K)

ξ2

0.512
200130.0130.2130.7
800132.0128.4126.8

Values of critical temperature differences ΔTcrdyn for the axisymmetrical m = 0 FEM plate model versus the imperfection ratio ξ2 under a temperature field with a positive gradient and two rates a = 200 K/s and a = 800 K/s_

Rate a (K/s)ΔTcrdyn (K)

ξ2

0.512
200115.2121.2129.2
800124.8128.0132.8

Values of critical temperature differences ΔTcrdyn for the asymmetrical m = 7 FDM plate model versus the imperfection rate ξ2 under a temperature field with a positive gradient and two rates a = 200 K/s and a = 800 K/s_

Ratio a (K/s)ΔTcrdyn (K)

ξ2

0.512
200107.4108.0108.2
800108.8108.4108.4

The values of the dynamic, critical temperature differences ΔTcrdyn depending on the number N of discrete points for the FDM plate model with the imperfection ratio ξ2 = 0_5 subjected to a positive gradient of the temperature field_

mΔTcrdyn (K)

N = 11N = 14N = 17N = 21N = 26
0128.6130.0130.1131.6131.5
1131.9133.7133.7134.2134.7
2133.5135.5135.5137.2137.0
3126.4129.3131.2130.9132.4
4117.5120.7122.1123.5124.8
5108.7112.3114.9115.9117.1
6105.7108.9110.4112.8113.8
7103.8106.8108.8109.5111.7
8103.7107.9110.3112.8116.4

The values of the dynamic, critical mechanical loads pcrdyn with the corresponding temperature differences ΔTb for the axisymmetric FDM plate model (m = 0) with the imperfection ratio ξ2 = 2 subjected to a mechanical load and increasing with the value a = 800 K/s temperature field with a positive gradient_

Number N1114172126
pcrdyn (MPa)/ΔTb (K)30.74/26.429.35/25.231.21/26.830.74/26.431.21/26.8

Parameters of the plate model_

Geometrical parameters
Inner radius ri, m0.2
Outer radius ro, m0.5
Facing thickness h′, mm1
Core thickness h2, mm5
Ratio of plate initial deflection ξ20.5, 1, 2
Material parameters
Steel facing Polyurethane foam of core
Young's modulus E, GPa210E2, MPa13
Kirchhoff's modulus G, GPa80G2, MPa5
Poisson's ratio ν0.3ν20.3
Mass density μ, kg/m37850μ2, kg/m364
Linear expansion coefficient a, 1/K1.2×10−5a2, 1/K7×10−5
Loading parameters
Rate of thermal loading growth a, K/s (TK7, 1/s)    200 (20), 800 (20)
Rate of mechanical loading growth s, MPa/s (K7, 1/s)    931 (20)
Constant temperature difference ΔT, K    800
DOI: https://doi.org/10.2478/sgem-2023-0005 | Journal eISSN: 2083-831X | Journal ISSN: 0137-6365
Language: English
Page range: 158 - 173
Submitted on: Sep 20, 2022
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Accepted on: Jan 5, 2023
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Published on: Apr 28, 2023
In partnership with: Paradigm Publishing Services
Publication frequency: 4 issues per year

© 2023 Dorota Pawlus, published by Wroclaw University of Science and Technology
This work is licensed under the Creative Commons Attribution 4.0 License.