A novel concept of discrete heat source array with dummy components cooled by forced convection in a vertical channel

•A novel concept of discrete heat sources with dummy components on substrate boards is presented.•Experiments are conducted to investigate the heat transfer behavior.•Full three-dimensional simulations done with COMSOL Multiphysics 4.3b to study heat and fluid flow behavior.•Single sided copper clad board is less expensive and gives significant heat dissipation.•Seven heat sources with four dummy components configuration results in maximum heat dissipation. This paper investigates the use of dummy components along with heat sources on a substrate board. Three-dimensional steady state laminar forced convection cooling of a discrete heat source array in a vertical channel is studied numerically and experimentally. The main objective of this study is to find the optimal distribution of seven heat sources with dummy components to minimize the substrate temperature. Air cooling of circuit boards populated with heat sources is modeled and simulated to present heat transport in combination with the fluid flow. This work also aims to study the effect of substrate thermal conductivity on fluid flow and heat transfer characteristics by using substrate boards of different thermal conductivities. The experiments are performed without dummy components and with 2, 4, 6, 8 dummy components at three different air velocities of 0.6, 1.0, 1.4 m/s. A correlation for θ in terms of Re, and k∗ is obtained.