White Papers
Beer Fridge: A Personal Journey
Mini-fridges, commonly filled with beer and the occasional moldering sandwich, have become a ubiquitous fixture in college dorm rooms and office break areas. But for some reason they never seem to cool their contents as well as their full-size cousins in the kitchen. This paper, based on a series of blog entries, presents a light-hearted look at the problem and offers a solution. In doing so, it demonstrates some practical thermal analysis methods using Mentor Graphics FloTHERM and proves that thermal simulation can help engineers design better products for consumers.
The Development of Libraries of Physical Models of Electrical Components for an Integrated Design Environment
This paper describes a 3-year European collaborative project, named DELPHI, whose goal was to address the lack of reliable, standardized input data needed to accurately predict the operating temperatures of critical electronic parts at the component-, board and system-level.
It includes a review of legacy methods for the thermal characterization of component packages with special emphasis on mono-chip packages.
Thermal Limits of Flip Chip Package - Experimentally Validated
This paper examines the thermal performance limits of a flip chip package. A PGA package with Direct Chip Attach (DCA) interconnect was chosen to demonstrate the approach.
Experiments were performed with a thermal test chip to validate the CFD model, which was used to predict the thermal performance limits of the package. Overall simulation and experimental to within 6%.
Thermal Modeling and Analysis of an Aircraft Electronics Navigation Unit
This paper describes the thermal modeling and analysis of a Transformer/ Rectifier Unit (TRU) unit attached to civil aircraft for high altitude navigation.
The objectives of the modeling project were to verify the viability of a conceptual design and to construct a validated numerical model to be used later for future analyses. Comparison between experimental and simulation showed good agreement.
3D Model to Analyse the Thermal Behaviour of a Digital Rectifier
This paper describes the 3D thermal investigation of a digital rectifier module, dissipating the maximum amount of heat when operating at 110V. A 3D numerical CFD model of the whole package was constructed in FloTHERM.
The results of several rectifier configurations (including changes in components arrangement and ventilation entrance/exhaust) were investigated in order to identify deficient ventilation and high temperature regions.
A Design Approach to Thermal Characterization of Forced Convection Systems Using Superposition in CFD
This paper shows how the adiabatic heat transfer coefficient concept can be used in system-level thermal design with CFD by exploiting the principle of superposition. The method requires no additional analysis methods except for matrix multiplication.
For forced convection systems where radiation and natural convection effects are minimal, the results of this study have shown excellent correlation.
CFD System Level Modeling of a Large Telecommunications Enclosure
This paper describes a methodology to creating compact models of heat exchangers used in a large telecommunications the enclosure. The model is validated against thermal tests and subsequently used to identify potential cost reductions in the design. The end result is a model that can predict with confidence multiple configurations of equipment inside the enclosure.
Characterisation of boundary conditions for an aircraft engine electronic control unit
This paper presents the thermal analysis performed on an aircraft engine Electronic Control Unit (ECU) installed in the engine environment. Part of the nacelle and ECU are modeled with and without cooling air, as specified by the engine manufacturer.
Different geometric configurations are simulated providing boundary conditions for a detailed thermal analysis of the ECU itself.
Competitive Analysis: 9 Slot CompactPCI Development Chassis
This article shows measured and simulated airflows through Hybricon’s 9 slot CompactPCI tower, demonstrating the accuracy of the simulations. Actual airflow measurements for two competitors’ enclosures are also presented to demonstrate just how important the simulation-measurement process is in chassis development.
FloTHERM simulations were compared with airflow and temperature measurements performed with Cambridge Accusense ATM-24 equipment.
DELPHI Compact Models Revolutionize Thermal Design
This study shows how DELPHI compact models are the method of choice for predicting the performance of IC packages in realistic electronics cooling environments. Although two-resistor models are useful in some design situations, the thermal community is already switching to the use of Delphi compact models due to their greatly superior performance and computational efficiency.
Design Characteristics of High Performance and Reduced Cost Chip Scale Package - µBGA
The thermal performance of four different kinds of μBGA structure of CSP (Chip Scale Package) was investigated using computational fluid dynamics. A major function of the package is to remove the heat generated by the IC chip.
This study explores in detail changes in the thermal performance possible as a function of die size and number of solder balls.