2010 - 19th Annual NC State Undergraduate Research Spring Symposium

Session Time : 4/22/10 10:30 AM - 4/22/10 11:45 AM

Content Area : Mechanical & Aerospace Engineering

Student Presenters :
Joseph John Elliott Mechanical Engineering

Mentors and/or Co-Authors :
Richard Gould Mechanical and Aerospace Engineering
Subhashish Bhattacharya Elec & Comp Engineering

Abstract Title : Design Considerations and Effect of Air Ducts on Flow Rate and Heat Transfer from a Series of Heat Sinks for Solid State Transformer.

Abstract :
This research was focused on measuring the effect of air ducts in different configurations on a series of heat sinks. The heat sinks are intended to dissipate heat generated by a 150W electronic device which is mounted to the top of each heat sink. The three heat sinks are arranged in a “train” with approximately 66mm of spacing between them. To achieve a temperature below the critical junction temperature for the electronics, forced convection is utilized to blow air across the heat sinks. Previous experimentation determined a flow velocity of 3-5 m/s was necessary to enable the appropriate heat transfer. To ensure the moving air produced in the forced convection situation was used most effectively, a duct was proposed as a method to channel the air across the heat sinks. The distance between the sides of the duct and the heat sinks was varied from 0-2 inches in the horizontal and vertical directions. The flow velocity was measured for each duct configuration, with the optimal design producing the 3-5 m/s velocity next to the heat sinks. In addition, the system curves of volumetric flow rate versus pressure drop for different duct sizes were determined. Utilizing the system curves, a fan that produces the flow rate required at the system pressure can be selected to minimize the amount of power needed by the cooling system. Ultimately, these system curves will allow an optimal fan to be selected for this system.