NEW METRO VEHICLE
GROUP-1 PROJECT YEAR WORK
A.Y.2019/20
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TEAM MEMBERS
SHANKAR MANI KANAGARAJ – 927894
SALMAN KHAN ZAKIR ALI KHAN - 927890
NEW METRO LINE DESIGN
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PROBLEM : 1
1.Modifying the main parameters of the vehicle (bogie wheelbase, masses, primary and secondary stiffness / damping parameters) so to meet the following requirements.
a)Axle load in tare condition <= 110 kN
b)Linear critical speed at full load with wheel conicity 0.40 >= 140 km/h. Consider a maximum payload of 280 kN
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TARE LOAD CONDITION
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AXLE LOAD IN TARE CONDITION:
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MAXIMUM PAYLOAD CONDITION
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Axle Load Under Maximum Payload <=280kN
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SOLUTION
Wheel conicity=0.40
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Mass of body=51000kg
PRIMARY SUSPENSION
Kxx=3.8e6N/m
Dxx=1.8e4Ns/m
Linear Critical speed
>=140kmph
RESULT: PS_KX=3.8e6;PS_DX=1.8e4: V=140kmph
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INFERANCE
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ITERATION | MODIFIED PARAMETERS | CRITICAL SPEED (Km/h) |
1 | PS_KX=2.768e6N/m | 120 |
2 | PS_KX=3.4e6 N/m | 131 |
…. | …. | …. |
n | PS_KX=3.8e6N/m PS_DX=1.8e4 Ns/m | 140 |
An increase in the primary suspension stiffness increases the diagonal terms of the stiffness matrix.
Therefore, this measure is generally increasing the critical speed of the vehicle.
A higher wheel conicity lowers the critical speed of the vehicle.
PROBLEM : 2
Run one Multi Body Simulation (MBS) with the vehicle running in tare condition at 5-10 km/h on a curve with radius R=150m and track twist g=1‰ (1E-3)
Check that Nadal’s criterion is satisfied across the entire curve.
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TRACK GEOMETRY
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Y/Q DERAILMENT COEFFICIENT: V=5kmph
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Y/Q DERAILMENT COEFFICIENT: V=10kmph
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Y/Q DERAILMENT CRITERIA
Nadal’s criterion is widely used for flange derailment which generally occurs in curves. The wheels on the outer rail experience higher lateral forces to vertical forces. The poor vertical load equalization can be caused by large track twists and roll resonances. The derailment also gets aided by track irregularities.
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PROBLEM 3
Analyse the running behaviour of the vehicle at full load in straight track at speed 60km/h and in a curve with radius R=150m , super elevation h=150 mm, considering the standard track irregularity in Sim-pack and wheel/rail profiles ORE S1002/UIC60 1:40.
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TRACK GEOMETRY
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SUM OF Y LATERAL FORCES
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Y/Q DERAILMENT COEFFICIENT: V = 60kmph
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STANDARD FOR EN14363
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60KN
WEAR NUMBER ( Kxx = 3.8e6 )
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WEAR NUMBER ( Kxx = 2.768e6 )
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WEAR NUMBER ( Kxx = 1.7e6 )
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WEAR NUMBER :
The wear number increases with increase in longitudinal stiffness and shows a trend of reduction for lower values of longitudinal stiffness of the primary suspension. Hence we can conclude that the wear number is directly proportional to the longitudinal stiffness of the primary suspension.
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PROBLEM :4
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Lifetime for rail welded joints
We investigate rail lifetime in presence of crack at the rail web in the middle of two sleepers. The crack is in the neutral axis and it propagates according to mode KII, namely under high values of shear load.
CRACK PROPAGATION IN WEB
Crack size = 30 mm -> 9716610 number of Cycles� Lifetime = 19.8072 years
Number of Trains =607290
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CRACK SIZE (mm)
NO OF CYCLES
�
CRACK PROPAGATION AT RAIL FOOT
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NEWMAN SOLUTION
K1c,1% (-10°C) = 20 MPa √m
K1c,1% (35°C) = 26.5 MPa √m
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CRACK AT FOOT OF RAIL
Frequency of Train= 14hours (6 Trains / hour)
Number of cycles = 3179200
Number of Trains=199760
No of years = 6.515
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NO OF CYCLES
CRACK SIZE (mm)
MODEL
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Reference:
1.Dynamics of Rail Transit Tunnel Systems by Shunhua Zhou – 8.6 dynamic response of the system by metro vehicle.
THANK YOU FOR YOUR ATTENTION!
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