Thermal analysis of automotive headlamps was conducted using CFD analysis to determine the correct vent hole locations for dissipating heat generated inside the lamp. The analysis found that the original vent hole number and locations were insufficient, causing heat to become trapped and lamp components to deform. The vent holes were optimized in number and position based on the CFD results, improving air flow and reducing maximum temperatures inside the lamp. Validation tests showed the design changes successfully addressed the overheating issues.

1. Thermal Analysis of Automotive Head Lamp Using CFD Analysis
Mr. Lalit Ahuja Mr. Vaibhav Wakchaure
Deputy General Manger CAE Engineer
Lumax Industries Ltd. Lumax Industries Ltd.
Chakan, pune Chakan, pune
Abstract
Thermal analysis of automotive lamps have become a significant part in the automotive industry’s design cycle due to the increased
demand from the customers for more durable and energy efficient products. The life cycle of the light and the lamp components greatly
depend on the thermal management of the lamp system. Thermal analysis of the lamps not only helps to increase the life time of the
lamp but also to determine its efficient operating conditions. This has been made possible with the increased growth in the field of CFD.
Objective
The objective is to find out the correct location of vent holes for hot air dissipation generated due to
bulb radiations inside the chamber to avoid the impact of heat on the plastic parts. We have carried out
thermal analysis of -Tata Motors SFC Head lamp using AcuSolve to find out the temperature distribution &
heat flow developed due to bulb temperature and radiation through reflective surface inside the lamp.
Introduction
As per the vehicle mounting condition head lamp need to be placed in the ambient air for testing.
Then the lamp is switched on as per std. for 24 hr. After testing period it is observed that the lamp
component gets deformed due to high heat generated in the lamp and improper heat dissipation through
vent holes provided. The number of vent holes provided or location of vent hole provided is not sufficient for
air circulation due to this hot air get trapped inside the lamp chamber and we observed deformation of lamp
component. To overcome this failure we perform the CFD Analysis considering all three modes of heat
transfer Conduction, Natural Convection and Radiation on head lamp Assembly.
Process Methodology
1) Geometry Import:
We have imported the Geometry in HyperMesh-11. CAD geometry needs to be clean up and done easily
with the help of HyperMesh which is pre-processing tool.
2) Meshing:
We have created the water tight geometry for surface meshing using R-Tria in HM by closing the vents.
Then we import surface mesh model in AcuSolve 1.8-b. We create the Volume mesh in AcuConsole very
easily with boundary layer mesh across the heat source (Bulb) for better flow of visualization and capture
temperature gradients around the bulb.
Simulation Driven Innovation 1

2. 3) Boundary Condition:-
We have assigned the material property for lamp component and temperature for heat source. we also
considered the outside temperature for analysis for the components which are exposed to the atmosphere.
4) Post Processing:-
For viewing the results we have used HyperView. Temperature plot on components, air flow through vent
holes, air flow inside of lamp are observed.
Results & Discussion
After getting results from AcuSolve we have exported the result data which is numerical format to
HyperView for post-processing.
Post-Processing:
Fig. 1: Temperature Counter on Head Lamp with new CAD
Simulation Driven Innovation 2

3. Fig.2: Temperature Counter on Head Lamp with old CAD
Fig.3: Path Lines Counter on Head Lamp with new CAD
Simulation Driven Innovation 3

4. Fig 4: Velocity Counter on Head Lamp with new CAD
Before CFD: Base Cad Model
Improvement location
Simulation Driven Innovation 4

5. After CFD: Optimized Cad Model
Improved location
As shown in above picture we made changes in the cad geometry and done the analysis. We increased the
number of vent holes and changed the location of vent holes for proper ventilation through lamp. This is
analyzed and validated for both thermal and structural vibrations.
Benefit Summary
Meshing of plastic parts is really typical. As we look into our Product – It is very complicated, specially the
Reflector and the Housing. HyperMesh helped us for meshing such complicated components with ease. for
air mesh and boundary layer mesh we use AcuSolve which is required very less time .After the Analysis we
found vent hole location is not accurate for air circulation we modify the location and also we modify the
material of component which can withstand the high temperature. Using HyperMesh along with AcuSolve
which has been successful solution for the above problem.
Challenges
Defect free launch and to overcome from Warranty issue later due to heat and field failure. To avoid Major
Material change later, if it fails. Having large reflectors in the head lamp, heat generated will be high so its
control and proper dissipation is another challenge.
Simulation Driven Innovation 5

6. Future Plan
Now in future we have introduced CFD Analysis as a part of Design Process during the Product Design
Stage. This helps us in validating the Product virtually and ensures good quality and Cost effective Product
before creating any Physical proto samples. And also to run a transient analysis to simulate the ON-OFF
condition for the lamps.
Conclusion
As per the analysis results, we found for Hot air circulation we required more vent hole with accurate
location and also we have changed Grade of the material having the HDT value.
Simulation Driven Innovation 6