Experimental Study of Loaded Foams During Free Fall Investigation and Evaluation of Microstructure

We aim to maintain as much control as possible over the development of the microstructure during the manufacture of polyurethane foam with a certain density. As a result, the finished product may not contain the required characteristics for the shock absorber used. That is why polyurethane foam loaded with zinc oxide and silica must be able to sustain the cellular structure and strengthen it. Mechanical characterization was carried out utilizing a dynamic drop impact test conducted on locally developed and constructed equipment. Polyurethane foams' mechanical properties are highly reliant on their density, cell structure (size and shape), and the fraction of open or closed cells. Within the cell structure, the foam may be directed preferentially. Following that, Raman spectroscopy and SEM investigation were used to visualize the semi-opened cells of the cellular polymer. The cellular polymer appears to possess permanent, regular cellular structures with a high degree of reversibility in terms of overlap.

Modeling the Performance of a Flat Solar Collector Based on Cellular Polymeric Materials

Currently, in the field of energy supply of agro-industrial facilities, there is an increasing interest in the development of new structures and engineering systems using solar energy, including flat solar collectors based on cellular polymer materials. Modern solar collectors based on metal absorbers, despite their high efficiency, have a large specific weight, high metal consumption and cost. The use of cellular polymer materials for the manufacture of solar collector absorbers reduces the cost and reduces the weight of the installation. (Research purpose) The research purpose is in conducting a numerical simulation of the performance of a flat solar collector based on cellular polymer materials. (Materials and methods) Authors used analytical methods for mathematical modeling of a flat salt collector based on cellular polymer materials. The article presents a mathematical model of a flat solar collector in the computer program ANSYS Fluent. The distribution contours of temperature and pressure of the coolant in the channels of a flat solar collector were obtained at different values of the coolant flow rate at the inlet. (Results and discussion) The article presents comparison the temperature of the coolant at the output of the solar collector on the flow rate of the coolant obtained analytically and using the developed CFD model. The results of verification of the calculated model of the solar collector showed its adequacy and high convergence of the data obtained using the computer model. (Conclusions) The article presents a design of a flat solar collector based on cellular polymer materials. The developed design of a flat solar collector allows us to reduce the specific weight more than three times and reduce the cost while maintaining high thermal performance.

Approaches Looking Finite Elements Analysis of a Structural Model of Lid Stratified with Cellular Polymeric Core Specific to a Pressure Vessel

The paper treats Finite Element Analysis (FEA) specific to the mechanical behavior of a structural layer cap type with polymer cellular cores within a pressure vessel. The layered composite structure comprises two outer polymer shells (synthetic glass/ plexiglass) and cellular polymer core with triangular shaped cells. This analysis uses the Autodesk Inventor 2016 Professional 3D design and modeling software, in conjunction with the FEA analysis program, ANSYS 14.5 - Workbench, using the Mesh module. Mechanical behavior of the structural models specific to the four types of test caps, each having different cellular polymer core (ABS, PLA, PC and CF, 3 and 5 mm thickness), is revealed through the analysis of the state of stresses and deformations and correlating the FEA simulation results with experimental testing. Since the analysis leads to quasi-equivalent results under identical conditions of application until the fracture of the caps, it is found that such an FEA approach of the mechanical system components occupies an important place in the modern design process, being one of the ways of identifying the deformation fields and equivalent stresses in the analyzed composite structures.

Electrostrictive energy conversion property of cellular electrets after corona discharge

In this paper, the authors present the electrostrictive energy conversion ability of cellular electrets after the high-voltage corona polarization. Moreover, the electrostrictive effect of such foamed polymer before and after corona polarization has also been compared and discussed. The enhancement of electrostrictive effect of cellular electrets after corona polarization was observed. In particular, the impact on the electrostrictive effect of the macroscopic electric dipoles inside of cellular polymer which are generated by high-voltage corona poling procedure has been investigated. The present research has promoted the development of the application of electret in the field of energy conversion, actuator, transducers, etc.