Pressure Measurements on Yacht Sails: Development of a New System for Wind Tunnel and Full Scale Testing

The paper presents an overview of a joint project developed among Politecnico di Milano, CSEM and North Sails, aiming at developing a new sail pressure measurement system based on MEMS sensors (an excellent compromise between size, performance, costs and operational conditions) and pressure strips and pads technology. These devices were designed and produced to give differential measurement between the leeward and windward side of the sails. The project has been developed within the Lecco Innovation Hub Sailing Yacht Lab, a 10 m length sailing dynamometer which intend to be the reference contemporary full scale measurement device in the sailing yacht engineering research field, to enhance the insight of sail steady and unsteady aerodynamics [1]. The pressure system is described in details as well as the data acquisition process and system metrological validation is provided; furthermore, some results obtained during a wind tunnel campaign carried out at Politecnico di Milano Wind Tunnel, as a benchmark of the whole measuring system for future full scale application, are reported and discussed in details. Moreover, the system configuration for full scale testing, which is still under development, is also described.