The noncondensable gas supported bubbles in an arterial heat pipe are studied. The governing conservation equations are solved to study the growth/collapse of spherical bubbles under different conditions by using the finite element method. The criterion used in the design of the venting pores to prime the artery is explained. The diffusion-limited bubble collapse in the condenser and bubble growth due to the phase change in the evaporator are both studied. A theoretical explanation for the capability of venting bubbles under different scenarios is provided. The experimental results, including rapid startup and condenser cooldown, are also presented to prove the ability of the heat pipes to vent vapor-gas bubbles. (C) 2009 Elsevier Ltd. All rights reserved.