Pressure measurements play an important role in the development of aircraft, both civil and military. For example, pressure measurements can provide valuable information on the pressure distribution on either the entire fuselage or locally on a particular section of a wing. Measurements are performed at varying speeds in order to obtain a complete set of information for different circumstances.
Another capability of DNW is to measure aerodynamic pressure fluctuations, both audible and non-audible. The results of these measurements help to solve aerodynamic vibration problems that eventually cause severe damage to the tail of an airplane with thrust reversers. And last but not least, pressure measurements by means of microphones are used to establish the precise location of noise sources on a model.
DNW provides a wide range of pressure measurements, varying from point measurements for a single point, surface measurements using pressure taps for wings and tails, and unsteady measurements, where pressure is measured as a function of time.
Pressure Measurement System (PMS)
Point measurements and surface measurements utilize sensors that are connected to a sophisticated Pressure Measurement System (PMS), in which a calibrated crystal reacts to the differences in pressure. DNW developed its PMS in close collaboration with Scanivalve. The collaboration between Scanivalve and DNW ensures that DNW’s customers are provided with pressure measurements that not only make use of state-of-the-art technology but also comply with the latest standards. Currently up to 1200 pressures can be measured simultaneously.
Pressure-Sensitive Paint (PSP)
In addition to PMS, DNW uses Pressure-Sensitive Paint (PSP), another important technology in surface measurements. The applied PSP method was developed by DLR. The main benefit of this method is that the pressure distribution of an entire model can be quantified.
Microphones
To measure fluctuating pressures, the signal of a microphone is recorded for a certain time period (e.g. 30 s). With this type of pressure measurements a tremendous amount of data is collected, usually consisting of terabytes of information. To manage this information, DNW has developed the Dynamic Data Acquisition system (DDA). This highly acclaimed system includes hardware and software for both data acquisition and data processing.