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Hydroplaning phenomenon is one of the major factors that must be considered to ensure safe driving on wet road surfaces. In this paper, the approach to numerical simulation of the physical hydroplaning characteristics using patterned tire is described. A detailed 3-D patterned tire model is constructed by in-house modeling program and the water flow is considered as incompressible. The complex tire material compositions are effectively modeled using composites, and rubber properties generalize the Mooney-Rivlin model. The finite element method (FEM) and the advanced finite volume method (FVM) are used for structural and for fluid-tire interaction analysis, respectively. Performance prediction of hydroplaning via coupling of computational fluid dynamics (CFD) and FEM has delivered a detailed insight into the local mechanisms and root causes of hydroplaning. Numerical examples were verified by comparing the experimental test results and it is confirmed to indicate similar correlation tendency and high reliability. The effect of driving velocity, pattern groove size, and pattern direction on hydroplaning phenomenon of tire is discussed and logical results were obtained.

Tire is the only part of the vehicle that contacts with the road surface and force-transmitting of steering. When a vehicle is driving on wet road surface at high speed, the water flow through the tire tread grooves generates the hydrodynamic pressure and loses the contact pressure. The occurrence of this hydrodynamic lift force deteriorates not only the tire traction efficiency but also the driving and the braking performance become worse [

Rotated tire numerical simulation on fluid flow is one of the challenging problems for CFD. In most CFD solver, the tire model is considered a rigid body without rotation or deformation. The adequate numerical method which allow to overcome these difficulties is needed to solve the problems. The main object of this paper is to study utilization of Flowvision-Abaqus co-simulation [

Different components of a typical radial tire are shown in

W ( J 1 , J 2 , J 3 : K ) = C 10 ( J 1 − 3 ) + C 01 ( J 2 − 3 ) + K 2 ( J 3 − 3 ) 2 (1)

where J i is the invariants of the Green-Lagrangian strain tensor and C 10 and C 01 are the rubber material constants determined from the experiment. On the other hand, K is a sort of penalty parameter controlling the rubber incompressibility. The shear modulus τ and the bulk modulus κ of rubber are related as 2 ( C 10 + C 01 ) = τ and K = 2 κ , from which one can easily obtain the following relation for Poisson’s relation:

ν = [ 3 K / 4 ( C 10 + C 01 ) − 2 ] / [ 3 K / 2 ( C 10 + C 01 ) + 2 ] [

elements. The rebar layers were embedded in the 3D solid by defining the nodes for rebar element. The embedded rebar elements were constrained to move relative host elements by a kinematic coupling which enforces the position of the host nodes and embedded rebar elements nodes to have a mutually linear dependency. In this study, two belt layers and carcass with embedded rebar elements are modeled. Meanwhile, steel cord and rubber matrix of the bead area is modeled as a homogeneous solid.

The CFD package from Capvidia [

After then Abaqus/explicit analysis will start to co-simulate with CFD software, to simulate the tire rolling over water films and investigate the performance of tire wet-grip capabilities. The whole analysis procedure is shown in

The link between FE and CFD meshes is built automatically via Flowvision Sub-Grid Geometry Resolution (SGGR) technique [

In this paper, water flow assumes that it is governed by system of equations for incompressible fluid which includes continuity and Navier-Stokes equations [

∂ p ∂ t + ∇ ⋅ ( ρ V ) = 0 (2)

∂ p V ∂ t + ∇ ⋅ ( ρ V ⊗ V ) = − ∇ P + ∇ ⋅ τ ^ e f f + ρ F (3)

Equations (2) and (3) were used to solve the velocity and pressure of fluid with a decouple process called as pressure and velocity split process [

∂ ( p k ) ∂ t + ∇ ⋅ ( ρ V k ) = ∇ ( ( μ + μ t σ k ) ∇ k ) + μ t ( G + β P r t g ⋅ ∇ T ) − ρ ε (4)

∂ ( p ε ) ∂ t + ∇ ⋅ ( ρ V ε ) = ∇ ( ( μ + μ t σ k ) ∇ ε ) + C 1 ε k μ t ( G + β P r t g ⋅ ∇ T ) − C 2 ρ ε 2 k (5)

The model parameters and the expression for generating term G can be rewritten as (6), (7), and (8):

G = D i j ∂ V i ∂ x j (6)

D i j = S i j − 2 3 ( ∇ ⋅ V + ρ k μ t ) δ i j (7)

S i j = ∂ V i ∂ x j + ∂ V j ∂ x i (8)

The object of this study is to investigate the resistance force of a rolling tires caused by fluid-dynamic, we will be introduced the similarity approach to experimentally measure the resistance of a tire rolling in a basin instead of wind tunnel for the validation of simulation. Therefore, the working fluid in this simulation is water, and heat transfer can be neglected reasonably. The units and numerical settings are listed in

P t o t = P + P h s t + 1 2 ρ | V a b s | 2 (9)

F fluid = ∮ s ( P + P h s t ) n d S − ∮ s ( μ + μ t ) ∂ V ∂ n d S (10)

The free surface flow is modeled by the “Advanced VOF model” in Flowvision [

∂ F ∂ T + V ⋅ ∇ F = 0 (11)

A representative tire model of passenger car is implemented to evaluate performance of hydroplaning. The size of tire is 205/55 R16 with simple tread pattern.

Notation | Physical quantity | Notation | Physical quantity |
---|---|---|---|

C P | Specific heat | P t o t | Total pressure |

G | Gravity acceleration | P r t | Turbulent prandtl number |

H | Total enthalpy | T t o t | Total temperature |

K | Turbulent energy | T r e f | Reference temperature |

L | Characteristic length | T a b s | Absolute temperature |

M | Molar mass | μ | Molecular dynamic viscosity |

P | Relative pressure | μ t | Turbulent dynamic viscosity |

P r e f | Reference pressure | V | Relative velocity |

P h s t | Hydrostatic pressure | ε | Dissipation rate of turbulent energy |

P a b s | Absolute pressure | β | coefficient of thermal expansion |

F | Variable of VOF | ∂ T | relative local specific |

Four different test tires with simplified tread patterns were produced and experiments evaluating of longitudinal hydroplaning test were carried out.

The measurement of hydroplaning performance by test tire is carried out on hydroplaning trailer. The hydroplaning trailer should be connected to a tow vehicle and drive left side of trailer to the wet test road. Then, measures speed of the test tire of left side of trailer and the tow vehicle. After that, calculate the hydroplaning occurred speed by compare speed of between the test tire and the vehicle. Specific test conditions are listed in

Slip ratio = 1 − Velocityofatire Velocityofatrailor (12)

The experimental rating indicates the trailer velocity, when the slip ratio is 10%. This is the way to obtain result in general experimental methods. The computational results used the contact force, when the simulation result is in stable.

Tire Type | Passenger Car Tire |
---|---|

Tire Size | 205/55 R16 |

Rim | 16 × 6.5 J |

Inflation Pressure | 207 kPa |

Water Depth | 10 mm |

Several different conditions were analyzed to confirm the consistency of the analysis procedure and results. Basically, the analysis results according to the driving velocity (50, 60, 70, 80, 90 km/h) were compared. And also the results according to the pattern shape were compared, because the pattern design factor had a dominant influence on the hydroplaning phenomenon.

To find out how the hydroplaning characteristics change at different speed, the same passenger car tire model is used to carry out the simulations at different speeds.

In a tire pattern design, the width of the longitudinal groove is one of the most

important factors to tire. It is necessary to increase the width of the groove to improve wet performance. In this section, hydroplaning simulation according to change groove width was conducted as shown in

Since the V-shape grooved tire has different hydroplaning velocities according to the normal and reverse rotational directions a closer look will be taken at this tread pattern design as shown in

A numerical method for predicting hydroplaning performance has been introduced in this paper using the coupling of CFD and FEM. The tire rotation which is difficult to apply in the general CFD solver was reflected, and the SGGR technique enables to detail fluid flow with complex tread pattern rolling in the computational domain without any feature loss. As compared hydroplaning performance, the simulation results were analyzed through buoyancy and contact force. Buoyancy is value caused by water pressure, large value means that hydroplaning performance is not good. But, contact force means force between tire and road, high value means good performance. To verify the effectiveness of the method, hydroplaning performance of four different simplified tread patterns are compared with experiments. It is confirmed that results agree well with each other for the cases considered. Furthermore, predicted water flows around the contact patch area agree well with those experimental phenomena. These agreements are thought to support the effectiveness of the present hydroplaning simulations. The effect velocity, groove size and directional patterns on the tire hydroplaning phenomenon were analyzed to confirm the consistency of the analysis procedure and results and logical results were obtained. As a result, the new numerical procedure proposed here enables one to predict the process of the hydroplaning of a tire and the difference of the hydroplaning performance dependent on the effect of the tread pattern and its geometry quantitatively. To obtain a more accurate analysis, it is required to proceed with the study applying the precise friction coefficient due to contact between tread rubber and the wet road in the future. It is expected that these frictional characteristics can be extended to simulate braking and handling performance on wet road.

The present study was supported by the Center for Environmentally Friendly Vehicles (CEFV) under the project “Development of the global top eco-friendly tire for reduction of tire wear particles and carbon dioxide” through the Ministry of Environment (ME, Republic of Korea).

The authors declare no conflicts of interest regarding the publication of this paper.

Jung, H.C., Jung, M.D., Jeong, K.M. and Lee, K. (2020) Verification of Tire Hydroplaning Phenomenon Using Coupled FSI Simulation by CFD and FEM. Open Journal of Applied Sciences, 10, 417-431. https://doi.org/10.4236/ojapps.2020.107029