Technical

ANALYSIS PROCEDURE

ANALYSIS PROCEDURE

Modeling

Model was constructed parametrically in the pre-processor of ANSYS. The dimensions for the original model are obtained by measurement from actual heat sink.

The new model is constructed based on the actual dimension of the existing model and the dimensional changes necessitated are incorporated within the allowable space. The direct generation   technique is adopted due to its inherent flexibility in parametric input of generation technique is adopted due to its inherent flexibility in parametric input geometry and case of meshing. The material of the heat sink is aluminium for which the thermal conducitivity is of 205 W/moC is specified.

 

LOADING AND SOULTINON

The original model of heat sink involves both free and forced convective heat transfer because of the presence of cooler fan. The convective heat transfer coefficient for both free and forced convections are calculated using dimensional analysis technique and the corresponding  values are applied at the boundary. The free and the corresponding values are applied at the boundary. The free and forced convective heat transfer coefficient are found to be 12 w/m20C and  58W/m20C respectively. It involves free convective heat transfer only because of the absence of cooler fan. Appropriate free convective heat transfer coefficient is applied for the proposed model.

The temperature of the heat sink where it is in contact with CPU is taken as 900C. The ambient temperature is taken as 300 corresponding to tropical conditions.