Measurements and Simulations of Wave Propagation for Wireless Sensor Networks in Jet Engine Turbines

Abstract

In this letter, measurements and simulations of wave propagation inside a jet engine fan have been performed. The investigation was done using both EM simulations of different cases of propagation inside the engine and by measuring the corresponding cases inside a half-scale model of a jet engine fan. The average path loss was calculated, and the shapes of the fading distributions were extracted. The time between two consecutive fading dips was measured in the empirical part. Measurements were performed with engine speeds of both 30 and 60 rpm and were shown to be linearly scalable from 60 rpm to full speed of 10 000 rpm. The results showed an average path loss of about 55 dB. When scaling the measurements from 60 rpm to full-speed rotation of about 10 000 rpm, the fading was so severe that the time slot between consecutive fading dips was limited to 290 s.

Modelling of EM propagation in simplified jet turbine structure using helical rays

“…Using the data obtained through the proposed model, the K-factor for a given frequency f and distance z was calculated using the average signal amplitude when going around the structure along a circular path. This was done in order to evaluate the fading experiences when rotating around the structure and to compare with the K-factors presented in [2,4]. The resulting plot is shown in Fig.…”

“…Discussion: The main purpose of this letter is not to provide a new way to calculate the field distribution inside the structure but rather to investigate whether propagating helical waves could explain the location and frequency dependence in the results obtained in [1][2][3][4]. Although the exact geometry of a jet turbine differs from the simplified model, here we have considered it very likely that the same underlying principle can be used to model the propagation behaviour in a real turbine engine.…”

“…Introduction: A number of recent studies [1][2][3][4] have measured the propagation behaviour of microwaves in jet turbine environments. In these studies, it has been found that propagating waves inside such a system suffer from heavy fading with large variations in the characteristics of the fading behaviour as a function of frequency.…”

Conformal circular patch antenna array design for use in jet engines

“…Since the jet engine environment is extremely complex with large number of metallic parts inside the environment with different size and shape, the designed antenna should be robust to the changes in the surroundings. The jet engine environment is a fading environment due to the presence of large number of scatters and reflectors [1]. Moreover, the antenna needs to be low profile with extremly thin substrate for not affecting the air flow through jet engine.…”

Statistical Analysis of Electromagnetic Field Inside a Jet Engine Using the Reverberation Chamber Approach

“…The statistical distribution of the field can be evaluated based on the field's cumulative density function (cdf). Analyzing the field nature inside the jet engine can be used in many future studies and applications such as to characterize the communication channel inside the jet engine for the purpose of monitoring its parameters like fuel consumption, pressure and temperature [18,19]. This paper reports results of a numerical study of the statistical nature of the field inside a simplified jet engine.…”