An invariant descriptor for conjugate forced convection-conduction cooling of 3D protruding heaters in channel flow

• Published in: Frontiers of Mechanical Engineering Vol. 10; no. 3; pp. 263 - 276
• Main Authors: ANTONINI ALVES, Thiago, SANTOS, Paulo H. D., BARBUR, Murilo A.
• Format: Journal Article
• Language: English
• Published: Beijing Higher Education Press 08-09-2015
• Subjects: channel flow; conjugate forced convection-conduction cooling; conjugate influence coefficients; discrete heating; Engineering; invariant descriptor; Mechanical Engineering; Research Article; thermal management; conjugate influence coefficients; invariant descriptor; discrete heating; thermal management; conjugate forced convectionconduction cooling; channel flow
• ISSN: 2095-0233; 2095-0241
• DOI: 10.1007/s11465-015-0345-y

In this research, the temperatures of three-dimensional (3D) protruding heaters mounted on a conductive substrate in a horizontal rectangular channel with laminar airflow are related to the independent power dissipation in each heater by using a matrix G + with invariant coefficients, which are dimensionless. These coefficients are defined in this study as the conjugate influence coefficients ( g +) caused by the forced convection-conduction nature of the heaters' cooling process. The temperature increase of each heater in the channel is quantified to clearly identify the contributions attributed to the self-heating and power dissipation in the other heaters (both upstream and downstream). The conjugate coefficients are invariant with the heat generation rate in the array of heaters when assuming a defined geometry, invariable fluid and flow rate, and constant substrate and heater conductivities. The results are numerically obtained by considering three 3D protruding heaters on a two-dimensional (2D) array by ANSYS/Fluent TM 15.0 software. The conservation equations are solved by a coupled procedure within a single calculation domain comprising of solid and fluid regions and by considering a steady state laminar airflow with constant properties. Some examples are shown, indicating the effects of substrate thermal conductivity and Reynolds number on conjugate influence coefficients.