Thermal Simulation, heat not spreading across to heat sink

I am currently doing my final year project on "Effective heat sink design for E27 LEDs".

I had done the design and thermal simulation on Solidworks 2013. However, after I ran my simulation I realized that the result is inaccurate. The heat source from the LED bulb is not spreading to the heat sink and the rest of the components.

The setup of the LED based on one plane of the symmetry are as such:

8W total LED bulb distributed through two bulbs. The LED bulb is attached on to a holder which is screwed onto the heatsink in the middle. The heatsink is then attached to the E27 holder.

I have been instructed to use the following settings for the convection setup:

Convection Coefficient: 25 W/(m^2.K), and ambient temperature of 300K.

I have tried to run the simulation but it always shows little thermal influence over the heatsink.

Can anyone help me with the above? Thank you.

SolidworksSimulation