Analysis of Exergy Destruction in a wind farm with complex terrain

Computational Fluid Mechanics (CFD) has proven to be an instrumental tool in the study of wind behavior in wind farms. While many authors focus on modeling turbines and wind farms in flat topography, complex terrain can impact wind development and power generation efficiency [1]. Exergy is defined as the potential of a system to perform useful work, where irreversibilities such as friction, destroy Exergy and hinder the wind farm’s performance. In this work we perform an Exergy analysis on a wind farm located in a complex topography. The goal is to identify and quantify the irreversibilities of the system resulting from the interaction between the wind, the turbines, and the terrain. We used the commercial software ANSYS Fluent™ to model the fluid mechanics, along with the Actuator Disk model to represent the turbines. We validated our numerical power results with field data from an operative wind farm. The Exergy Destruction is mainly caused by the dissipation of turbulent kinetic energy as a result of the topography’s complexity. The Exergy Destruction contours allow us identifying optimal locations for turbines and can serve as a useful tool for wind farm design.