In this paper, to determine the impact of carbon fiber orientation and interweaving on electromagnetic interference (EMI) shielding behaviors, anisotropic and isotropic samples were developed by conductive/dielectric weaving of spatially distributed carbon fiber and glass fiber. Effortless and cost-effective, the electromagnetic shielding efficiency (SE) was up to 42 dB and the SE/thickness) was 41 dB/mm, which had apparent polarization selection characteristics. In addition, the angle (θ) sensitivity for the SE in transverse electric and transverse magnetic polarization modes was given in detail. SE was generally proportional to θ. Moreover, the fingerprint-like radar chart of anisotropic carbon hybrid woven fabrics in the X-band was performed, which makes polarization selection characteristics more intuitive. This paper presented an easy and effective route for assembling hybrid carbon fiber fabrics with high EMI shielding performance, which offers a clear perspective on the simulation and study of carbon fiber electromagnetic properties.

In order to reduce the fiber diameter and the energy consumption in the meltblowing process, a modified slot die with two blocks was designed in this article. The numerical calculation and the experimental verification of the airflow field under the modified slot die were carried out, and the effect of the block structure parameters on the air field was investigated. The research results indicate that compared to the common slot die, the modified slot die with the blocks could increase the velocity on the spinning line and reduce the rate of the temperature decay on the spinning line. When the block width and the block inclination angle lower, and the block height expands, it could increase the peak of the air velocity, the temperature and the turbulence intensity on the center line of the air field under the modified slot die. The average velocity on the spinning line of the modified die under the conditions of block width = 20 mm, block height = 30 mm and block inclination angle = 60° is the highest.

In this paper, frequency selective fabrics (FSFs) with narrow-band transmission characteristics were proposed. The square-ring FSF was taken as an instance to illustrate the design principle. Based on the existing theoretical basis and by means of software simulation and optimization, the optimum structures with ideal narrow-band band-stop or band-pass characteristics were obtained. Then, the practical specimens were manufactured through a computer-based carving process and measured using the transmission method in an anechoic chamber. Two structural models were respectively simulated using two different algorithms and the results showed very small differences, primarily verifying the effectiveness of the design methods and reasonability of the model simplification. The measured and simulated transmission characteristics of square-ring FSFs were compared and showed a high consistency, which further verified the validation of the design method. The other two kinds of FSFs, namely Jerusalem-shaped and circle/ring hybrid FSFs, were designed and measured, which showed the narrow-band frequency selective characteristics were quite ideal. This indicates that the proposed design method using simulation software may be applied to many different structures and has directive sense in the related product design and development process.