Comparison of PSD Analysis Methods in Frequency Domain Fatigue Analysis

Jang, Jinho; Cho, Jae Myung; Lee, Kwang Hee; Lee, Won Woong; Choi, Woo Chun

doi:10.7736/kspe.2019.36.8.737

Cited by 4 publications

(2 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the Lalanne approach, the probability density function (PDF) of peaks is assumed to be the simple sum of Gaussian and Rayleigh distributions [ 58 ], while the Dirlik approach assumes the PDF of peaks is a combination two Rayleigh densities and an exponential. Due to this assumption, the cycle counting distribution in the Dirlik approach decays faster compared to that of the Lalanne method, as shown in Figure 16 .…”

Section: Resultsmentioning

confidence: 99%

“…The cycle counting results using the Lalanne, Dirlik, and narrow-band approaches for the measured responses are illustrated in Figures 15-17, respectively, while a summary of the results is presented in Table 6. In the Lalanne approach, the probability density function (PDF) of peaks is assumed to be the simple sum of Gaussian and Rayleigh distributions [58], while the Dirlik approach assumes the PDF of peaks is a combination two Rayleigh densities and an exponential. Due to this assumption, the cycle counting distribution in the Dirlik approach decays faster compared to that of the Lalanne method, as shown in Figure 16.…”

Section: Forced Vibration Analysis Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Vibration-Based Fatigue Analysis of Octet-Truss Lattice Infill Blades for Utilization in Turbine Rotors

et al. 2022

View full text Add to dashboard Cite

Vibration fatigue characteristics are critical for rotating machinery components such as turbine rotor blades. Lattice structures are gaining popularity in engineering applications due to their unique ability to reduce weight and improve the mechanical properties. This study is an experimental investigation of octet-truss lattice structure utilization in turbine rotor blades for weight reduction and to improve vibration fatigue characteristics. One completely solid and three lattice infilled blades with variable strut thickness were manufactured via additive manufacturing. Both free and forced experimental vibration analyses were performed on the blades to investigate their modal and vibration fatigue characteristics. The blades were subjected to random vibration using a vibration shaker. The response was measured using a triaxial accelerometer in terms of vibration acceleration time histories in the X, Y, and Z directions. Results indicate a weight reduction of up to 24.91% and enhancement in the first natural frequency of up to 5.29% were achieved using lattice infilled blades. The fatigue life of the blades was investigated using three frequency domain approaches, namely, Lalanne, Dirlik and narrow band. The fatigue life results indicate that the 0.25 mm lattice blade exhibits the highest fatigue life, while the solid blade exhibits the lowest fatigue life of all four blades. The fatigue life of the 0.25 mm lattice blade was 1822-, 1802-, and 1819- fold higher compared to that of the solid blade, using the Lalanne, Dirlik, and narrow-band approaches, respectively. These results can serve as the first step towards the utilization of lattice structures in turbine blades, with thermal analysis as the next step. Therefore, apart from being light weight, the octet-truss lattice infilled blades exhibited superior vibration fatigue characteristics to vibration loads, thereby making them a potential replacement for solid blades in turbine rotors.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Forced Vibration Analysis Resultsmentioning

confidence: 99%