This article is dealing with properties overview of thermal turbulences influencing optical beam of atmospheric optical link. The team of authors was focused on simulation of thermal turbulences caused by hotplate heater that heated water up to boiling point. Thermal turbulences were fanned by three high-speed ventilators and were kept in the wooden box to achieve stable conditions with the respect to effect on optical beam transmitted by atmospheric optical link. The measurement of the thermal turbulences influence was performed in distance of 3 and 10 meters from the optical head. The wooden box was placed directly in front of the optical head. Moreover the numerical profile of turbulent behavior was designed for air flow in the wooden box thanks to Ansys Fluent software application.