Application Cases

Experiment Title: Aircraft Icing Detection Based on Piezoelectric Materials

Experimental Principle:
Ultrasonic guided waves are excited by a piezoelectric transmitting sensor on the surface of an aluminum plate model. When these waves propagate across the aluminum plate and encounter an ice layer, they undergo a series of changes. The alternating voltage signal generated by the piezoelectric effect is then received by a receiving piezoelectric sensor on the opposite side. The collected signal is subsequently processed and observed using an acquisition system connected to an upper computer.

Figure a: Workflow Diagram of the Icing Detection System

Test Equipment:
Signal generator, ATA-8202 RF power amplifier, piezoelectric ceramics, signal acquisition card, computer software.

Experimental Procedure:
This experiment uses the NACA0012 airfoil as the model, as shown in Figure b. The entire airfoil is clamped on a support platform. Similar to a parallel layout, eight piezoelectric actuators are installed on one side, and eight receiving sensors are placed on the opposite side. During data acquisition, the eight sensors on one side sequentially emit signals, while the eight sensors on the opposite side receive the signals. Thus, in one operational cycle, a total of 8 × 8 = 64 sets of data are collected. The ATA-8202 serves as the driving source, and a Tektronix oscilloscope provides the signal. The software integrates five functional modules: signal generation control, acquisition card control, signal detection, signal acquisition, and result analysis.

Figure b: Physical Layout Diagram of the Airfoil

Although there is a certain curvature, the waves excited in this setup are still ultrasonic guided waves, albeit with more complex modal characteristics. By observing a set of signals, as shown in Figure c, it is evident that modal conversion phenomena occur to varying degrees under these wing conditions. Analyzing a single pair of sensors makes it difficult to extract useful icing information, requiring the use of probabilistic reconstruction algorithms and localization algorithms to approximate icing characteristic parameters. This demonstrates that ultrasonic guided wave icing detection technology is feasible in complex or more realistic scenarios, though certain challenges remain.

Figure c: Guided Wave Signal Diagram of the Airfoil

Figure d: Probability Map of Icing on the Airfoil Layout

As visually depicted in Figure d, the probability of icing on the airfoil image is slightly lower than that in the parallel layout, with slightly weaker accuracy, and the range of high probability is also larger than in the parallel layout. However, the presence of ice can still be detected, providing a general indication of icing conditions in the monitored area.

Experimental Results:
In the airfoil layout, the presence of icing can be detected, and the region with the most severe icing can generally be identified. However, some errors exist in non-icing areas, leading to less-than-ideal icing reconstruction images. This phenomenon may be attributed to the following reasons: under the airfoil layout, icing is artificially induced by water spraying, resulting in uneven ice types with dense pores. When guided waves pass through the icing area, the reflection and scattering phenomena of the ice layer are highly complex, causing the signals received by the sensors to exhibit waveform superposition, which deviates significantly from the ideal results. Additionally, thin airfoil structures are difficult to manufacture, and processing errors may occur during the production of the airfoil structure. Furthermore, ice thickness and ice morphology (such as frost ice, clear ice, and mixed ice) also affect the results to some extent.

The ATA-8202 RF power amplifier features a P1dB output power of 100W and a saturated output power of 200W. With digitally adjustable gain and one-click save settings, it offers convenient and straightforward operation. It is compatible with mainstream signal generators, enabling perfect amplification of RF signals. Its wide-range power supply is compatible with power standards in different regions worldwide.

The experimental materials in this article were compiled and released by Xi’an Aigtek Electronics. For more experimental solutions, please continue to follow the Aigtek official website.