This document describes XLVCEL software for simulating the Morton effect and predicting bearing dynamic coefficients. It can: 1. Perform nonlinear transient and steady state simulations of the Morton effect instability considering thermal gradients in the shaft and bearing. 2. Model 3D fluid film bearings with pad flexibility, rocker or spherical pivots, and asymmetric film clearance. 3. Support a finite element model of a flexible rotor supported by two nonlinear bearings.

1. 𝑿𝑳𝑽𝑪𝑬𝑳 𝑻𝑴 Morton Effect and Bearing Simulation Software
by Dr. Alan Palazzolo, a-palazzolo@tamu.edu and Mr. Xiaomeng Tong, tongxiaomeng1989@tamu.edu
XLVCEL
Objective: User friendly software package for prediction of Morton Effect and bearing Dynamic Coefficients
with the consideration of 3D fluid film bearings, flexible rotor and 3D heat conduction and convection.
Shaft Thermal Bending Induced Synchronous Rotor Instability Problem
Double
Overhung
Morton Effect
Single
Overhung
Morton Effect
Dynamic
Coefficients
Ver. 1.01
2
3tilting pad.
fixed pad.
pressure dam.
flexure pivot[KMC].4
1 2 3
a flexible/rigid pad. b flexible/rigid pivot.
c cylindrical/spherical pivot.
a b c
a
b
c
1 2
3 4
a b c
No MATLAB
Required
Nonlinear Transient
Morton Analysis
Nonlinear Steady
Morton Analysis
Dynamic Coefficient
Prediction
1 2 3 4
Nonlinear Transient
Morton Analysis
Nonlinear Steady
Morton Analysis
Dynamic Coefficient
Prediction
Bearing Type Available Options
1.Nonlinear Transient/Steady Simulation for the
Morton effect induced instability.
 Thermal gradient in shaft and bearing
 Parameter effect: oil temperature
2.Bearing Static and Dynamic Solver
 3D bearing model with pad flexibility
 Rocker/spherical pivot with nonlinear stiffness
 Asymmetric film clearance
1. Finite Element Dynamic Rotor Model
Supported in Two Nonlinear-Bearings
0
0.2
0.4
0.6
0.8
1
-0.2
0
Z axis (m)
Rotor Geometry Check, Red:BRG1 , Blue:BRG2, Black:LIN BRG
(m)
1. Finite Element Rotor
Maximum No. of Elements = 80
Number of Inputs 19 Number of Elements 19
Input No. ElementNo. Material Group No. Length(m) OuterDiameter (m) InnerDiameter (m)
1 1 1 0.02667 0.197612 0
2 2 1 0.077724 0.113538 0
3 3 1 0.054356 0.082296 0
4 4 1 0.06858 0.082296 0
5 5 1 0.06858 0.082296 0
6 6 1 0.041148 0.122428 0
7 7 1 0.07112 0.357378 0
8 8 1 0.148844 0.122428 0
9 9 1 0.12446 0.184404 0
10 10 1 0.12446 0.184404 0
11 11 1 0.046736 0.1016 0
12 12 1 0.04318 0.1016 0
13 13 1 0.108712 0.093472 0
14 14 1 0.085344 0.082296 0
15 15 1 0.0127 0.11303 0
16 16 1 0.019304 0.50673 0
17 17 1 0.019304 0.50673 0
18 18 1 0.019304 0.433832 0
19 19 1 0.03302 0.282448 0
a. Pads Geometry
Pad Flexibility (0:Rigid, 1:Flex) 0
Bearing Load Type (0:LOP, 1:LBP) 0
Number of Pads 5
Pad Arc Length (degree) 56
Offset 0.5
Radius of Shaft at BRG (m) 0.0508
Bearing Clearance, CL_B (m) 7.48E-05
Preload 0.5
Pad Thickness (m) 0.0127
Pad Thickness at Pivot (m) [Cylindrical Pivot]
(> Pad Thickness)
0.015
Bearing Length (m) 0.0508
b. Pivot Geometry ( Pad Motion and Stiffness )
Pivot Type(1:Spherical 2:Sphere-in-a-Cylinder,3:Cylindrical) 1
Pivot Stiffness (0: Rigid, 1: Linear+Cubic, 2: Nonlinear) 0
b-1: Linear+Cubic Pivot Stiffness
Linear Stiffness Coefficient (x)[N/m] 8.00E+08
Cubic Stiffness Coefficient (x^3)[N/m]^3 0.00E+00
b-2: Pivot Geometry for Nonlinear Pivot Stiffness (not for Dyn.Coeff)
[1.Spherical] : Dh [m] 0.01
[1.Spherical] : Ratio of (Dp/Dh) (<1) 0.98
[2.Sphere-in-a-Cylinder] : Dh [m] 0.01
[2.Sphere-in-a-Cylinder] : Ratio of (Dp/Dh) (<1) 0.98
[3.Cylindrical] : Dp1 [m] -Radial 1.24E-01
[3.Cylindrical] : Ratio of (Dp1/Dh1) (<1) 0.8895
[3.Cylindrical] : Dp2 [m] -Axial 2.54E+00
[3.Cylindrical] : Ratio of (Dp2/Dh2) (<1) 0.0000001-0.05
0
0.05
-0.15
-0.1
-0.05
0
0.05
0.1
0.15
-0.06
-0.04
-0.02
0
0.02
0.04
0.06
X axis
MESH AND B MATRIX CHECK PLOT
Z axis
Yaxis
2. 3D Finite Element Bearing Model
0.04
0.06-0.02
0
0.02
-0.03
-0.02
-0.01
0
0.01
0.02
0.03
X axis
frequency =0(Hz)
Y axis
Zaxis
0.04 0.05 0.06 0.07
-0.03
-0.02
-0.01
0
0.01
0.02
0.03
frequency =0(Hz)
X axis
Yaxis
0.04
0.06-0.02
0
0.02
-0.03
-0.02
-0.01
0
0.01
0.02
0.03
X axis
frequency =33639(Hz)
Y axis
Zaxis
0.04 0.05 0.06 0.07
-0.03
-0.02
-0.01
0
0.01
0.02
0.03
frequency =33639(Hz)
X axis
Yaxis
NUMERICAL MODELING OF ROTOR-BEARING SIMULATION RESULT
-0.25 -0.2 -0.15 -0.1 -0.05 0 0.05 0.1 0.15 0.2 0
-0.1
-0.05
0
0.05
0.1
80
82
82
78
79
80
81
70
70
80
80
90
90
70
70
80
80
90
90
Temperature Distribution on Bearing and Shaft from Cross View
Axial Direction (m)
Yaxis(m)
-0.08 -0.06 -0.04 -0.02 0 0.02 0.04 0.06 0.08
-0.08
-0.06
-0.04
-0.02
0
0.02
0.04
0.06
0.08
Temperature distribution (Celsius)
X axis
Yaxis
68
70
72
74
76
78
80
60
61
62
63
64
65
58
58.5
59
59.5
60
60.5
61
61
62
63
64
65
66
68
70
72
74
76
78
68
70
72
74767880
82
5859
60
61
62
63
64
65
66
57
58
59606162
59
60
61626364656667
64
66
68
70
72
74767880
68.2
68.4
68.4
68.6
68.6
68.8
68.8
69
69
69
69.2
69.2
69.2
69.4
69.4
69.4
69.6
69.6
69.6
69.8
69.8
69.8
69.8
70
70
70
70
3D Thermal Gradient in the Shaft
Nonlinear Steady Morton Effect Analysis
𝑉𝑖𝑏𝑟𝑎𝑡𝑖𝑜𝑛
50℃30℃
unstable
unstable
Reduce Oil Temp--
Instability Band Shifts Left
𝑅𝑜𝑡𝑎𝑡𝑖𝑜𝑛𝑎𝑙 𝑠𝑝𝑒𝑒𝑑
Nonlinear Transient Morton Effect Analysis