In this work, adhesion system for wall climbing robots, known as "vortex attractor", has been studied analytically, numerically and experimentally. Vortex attractor system consists of the following components: vortex cup, centrifugal fan and an electrical motor. In this design, vortex flow which is generated at the fan impeller eye produces a considerable suction pressure. Knowing this fact that the air flow is trapped inside the cup, the suction force increases and also power consumption is reduced. Firstly, an attractor system is manufactured considering necessary measurement facilities. The effect of different parameters such as rotational speed and gap between system and surface on system performance is investigated. Numerical simulation of vortex attractor system is performed using CFX software. The numerical results were verified through grid independency and validated with comparison with those obtained from measurements. In the next step analytical study is carried out using Rankine vortex. Experimental results show that as gap increases, power consumption increases. In the case of vortex attractor stick to surface, repulsive force is observed. Analytical results show that generated force and pressure are proportional to square of rotational speed.