Analysis of Moisture and Natural Convection Inside an Automotive Headlamp by Using CFD

2005-01-1449

04/11/2005

Event
SAE 2005 World Congress & Exhibition
Authors Abstract
Content
Since an automotive headlamp is very complicated structure, CFD (Computational Fluid Dynamics) had the problem of being very difficult. Especially, if radiation is taken into consideration, the memory required for calculation is huge.
In the present study, the first aim was to develop the new calculation technology that was called FSI-DM, that is a unique technique, in which the calculation mesh generated in the fluid were made discontinuous on the solid and fluid surface. In this FSI-DM, radiative heat transfer was calculated with using the coarse mesh generated on the solid surface to reduce memory size in order to use practical, and it enable us to predict velocity and temperature on the inner parts of an automotive headlamp comparatively accurately.
Next, FSI-DM was further extended so that it would be able to be applied for moisture condensation on the lens surface. In order to express moisture condensation, moisture transfer model was developed using analogy that was formed between the temperature equation and the diffusion equation. This analogy model for moisture was applied to the spherical lamp and actual headlamp with a complicated structure, and it shows that plastic which was constitute headlamp emits moisture when lighting the bulb and that misting occurs when the lens surface is rapidly cooled. Furthermore, the same thing checked also in the experiment qualitatively but quantitative evaluation.
Meta TagsDetails
DOI
https://doi.org/10.4271/2005-01-1449
Pages
14
Citation
Shiozawa, T., Ohishi, M., Yoneyama, M., Sakakibara, K. et al., "Analysis of Moisture and Natural Convection Inside an Automotive Headlamp by Using CFD," SAE Technical Paper 2005-01-1449, 2005, https://doi.org/10.4271/2005-01-1449.
Additional Details
Publisher
Published
Apr 11, 2005
Product Code
2005-01-1449
Content Type
Technical Paper
Language
English