Visual and quantitative investigation on heat flow performance from heat sinks using digital holographic interferometer

Thermally Conductive (TC) Plastics in LED Lamps

Additional Conferences (Device Packaging HiTEC HiTEN & CICMT) ◽

10.4071/2010dpc-wa41 ◽

2010 ◽

Vol 2010 (DPC) ◽

pp. 001514-001539

Author(s):

Rob Janssen ◽

Ir. L. Douven ◽

H. K. van Dijk

Keyword(s):

Thermal Conductivity ◽

Heat Flow ◽

Thermal Performance ◽

Heat Sinks ◽

Complex Case ◽

Ideal Case ◽

General Validity ◽

Trade Off ◽

Thermally Conductive ◽

The Ideal

In section 1, an assessment is made of the typical thermal conductivities attainable in a TC-plastic followed by an examination of the trade-off between increased thermal conductivity and decreased toughness caused by increasing filler load of such a TC-plastic. Having established that currently there is a ceiling conductivity of around 25 W/mK for TC-plastics, i.e., well below the 100 W/mK TC level of metals, subsequently a basic analysis is provided on the suitability of materials with such moderate TC-levels in metal replacement. For this purpose, the ideal case of a unidirectional (1D) heat flow is considered in section 2, in section 3, a more complex case of a bidirectional heat flow is analyzed. Finally, section 4 considers the thermal performance of TC-plastics in a real 3D part, i.e., the heat sink housing of an LED lamp. More specifically, a comparison is made between the thermal performance of the housing molded in a heat conductive plastic and that of an all-aluminum housing. This comparison clearly demonstrates general validity and practical value of the conclusions drawn in sections 2 and 3 and highlights the outstanding suitability of TC-plastics for heat sinks in lighting applications. High performances STANYL TC in particular.

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Computer Simulation of Heat Flow Induced by Laser Irradiation in Presence of Heat Sinks or Sources

MRS Proceedings ◽

10.1557/proc-279-35 ◽

1992 ◽

Vol 279 ◽

Author(s):

Sebastiano Tosto

Keyword(s):

Computer Simulation ◽

Thermal Properties ◽

Heat Flow ◽

Laser Irradiation ◽

Thermal Field ◽

Heat Sinks ◽

Heat Sources ◽

Local Phase ◽

Additional Energy ◽

Heating And Cooling

ABSTRACTThe paper concerns the computer simulation of heat flow induced on matter by laser irradiation in presence of heat sources or sinks. The model is 3D analytical and accounts for the dependence of thermal properties of matter on temperature. The results describe in particular the effect of a heat source due to a local phase change or solid state reaction releasing energy in a point of the laser affected zone. The purpose of the paper is to evidence how this additional energy affects the thermal field and then the heating and cooling rates. PACS 47.25.-Qv

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Design of passive heat sinks to power semiconductor with the cesaro curve

Revista Facultad de Ingeniería Universidad de Antioquia ◽

10.17533/udea.redin.20200162 ◽

2020 ◽

Author(s):

Luis Carlos Ruiz-Cardenas ◽

Luis Eduardo Llano-Sánchez ◽

Dario Manuel Dominguez Cajeli ◽

Martha Cecilia Melo de Alonso ◽

Carolina González-Rodríguez

Keyword(s):

Thermal Analysis ◽

Heat Flow ◽

Heat Sink ◽

Heat Sinks ◽

Electronic Circuits ◽

Power Semiconductors ◽

Power Semiconductor ◽

Signal Characteristics ◽

Power Stage ◽

Low Performance

In the design of electronic circuits, stands out the power stage, which is responsible of increasing the signal characteristics, as current and voltage, for an appropriate performance of the device to fabricate. However, this stage is composed of elements like transistors, which may have a low performance, due to the undesired temperature increase, as a result of reaching the desired power. To mitigate the loss of power and with it, the temperature rise, the management of heat sink is proposed, in order to keep the work of the power stage at a stable level and avoid thermal fractures within the circuit. This manuscript presents the obtained results of the thermal analysis in finite elements of the heat sink with fins in the form of a Cesaro curve, for power semiconductors, which evidence the increase in the heat flow, with respect to the commercial ones and so, facilitate the heat evacuation for conditioning the voltage and/or current.

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