Harvesting vibrational energy with a droplet engine

Abstract

In the past years there has been a increased interest in systems that convert energy from ambient vibrations into an electric current. These ambient vibrations are, for example, generated by cars driving on the roads or big machines such as air conditioning units, and usually dissipate into the surroundings. Although not much energy is to be gained from these ambient vibrations, enough can be harvested to power small devices like sensors. The aim of this thesis is to obtain a theoretical analysis of a novel vibrational energy harvester, consisting of two parallel, conducting plates bridged by a water droplet and connected to a bias voltage. In three phases we will work towards a realistic model of a vibrational energy harvester. The first phase concerns the geometry of the droplet, the subject of the second phase is the energy conversion process, while in the third phase the droplet engine in included in an electrical circuit and the dynamics of the system is analysed. At the end we will be able to give an overview to engine designers on how to optimise the vibrational energy harvester.