A Robust Testing Method for Determination of the Damping Loss Factor of Composites

This paper deals with expanded polystyrene (EPS) as a potential source of smoke. We compared specific optical density of smoke from EPS and EPS strengthened by glass fibre mash and plaster which is used in external thermal insulation composite systems (ETICS). There was used testing method by ISO 5659 Plastics Smoke generation Part 2: Determination of optical density by a single-chamber test. The samples were exposed to a constant 50 kW.m-2 of thermal radiation. There was not used a pilot burner. During flame combustion samples evolved high amount of smoke. Samples from EPS released more smoke like samples with ETICS cover.

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Measurement of Elastomer's Bulk Modulus by Means of a Confined Compression Test

Rubber Chemistry and Technology ◽

10.5254/1.3538718 ◽

1994 ◽

Vol 67 (5) ◽

pp. 871-879 ◽

Cited By ~ 14

Author(s):

Shu H. Peng ◽

Takao Shimbori ◽

Akbar Naderi

Keyword(s):

Bulk Modulus ◽

Volume Change ◽

Treatment Technique ◽

Pressure Loading ◽

Confined Compression ◽

Routine Test ◽

Simple Method ◽

Testing Method ◽

Analysis Technique

Abstract The bulk modulus represents a material's resistance to volume change when subjected to pressure loading. Determination of bulk modulus is important for evaluation of applications where compression is involved. Most methods proposed for this purpose are complicated and costly. A simple method is to compress an elastomer button, fully confined in a metal fixture, on a tensile/compression machine. The reliability of this method is studied and a data-treatment technique is proposed to improve the accuracy. It shows that the testing method, with the new analysis technique recommended, is efficient and can be used as a routine test.

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Qualitative and quantitative determination of densely occurring defects in steel ropes by magnetic testing method

NDT International ◽

10.1016/0308-9126(89)91326-6 ◽

1989 ◽

Vol 22 (1) ◽

pp. 55

Keyword(s):

Quantitative Determination ◽

Qualitative And Quantitative ◽

Testing Method ◽

Magnetic Testing

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Determination of repeatability and reproducibility of standard testing method using computer.

Kvasny Prumysl ◽

10.18832/kp1984020 ◽

1984 ◽

Vol 30 (5) ◽

pp. 105-108

Author(s):

J. DUŠEK ◽

H. NĚMĚČKOVÁ

Keyword(s):

Standard Testing ◽

Testing Method ◽

Repeatability And Reproducibility

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Determination Of Thermal Parameters Of Solar Water Heating Collectors Using The “Dark” Testing Method

The American Journal of Applied Sciences ◽

10.37547/tajas/volume02issue11-11 ◽

2020 ◽

Vol 02 (11) ◽

pp. 62-67

Author(s):

Nizomjon Orifovich Usmonov ◽

◽

Xayrulla Sunnatullaevich Isakhojaev ◽

Saodat Rakhsulaevna Akhmatova ◽

Feruza Abdullaevna Khoshimova ◽

...

Keyword(s):

Thermal Characteristics ◽

Hot Water ◽

Thermal Testing ◽

Water Heating ◽

Solar Water Heating ◽

Solar Water ◽

Testing Method ◽

Hot Water Supply ◽

Hot Water Supply System

In the production of flat solar water heating collectors, thermal testing occupies a special place, the purpose of which is to determine their thermal characteristics experimentally. The corresponding approximation expressions are proposed for determining the coefficient of heat loss, inclined to the horizon at an angle of 300 for the average conditions of their operation in the hot water supply system

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A New Methodology for the Accurate and Consistent Identification of Modal Parameters Using Multi-FRF Analysis

Volume 3B: 15th Biennial Conference on Mechanical Vibration and Noise — Acoustics, Vibrations, and Rotating Machines ◽

10.1115/detc1995-0522 ◽

1995 ◽

Author(s):

R. M. Lin ◽

S.-F. Ling

Keyword(s):

Eigenvalue Problem ◽

Loss Factor ◽

Frequency Response Function ◽

Natural Frequencies ◽

Identification Problem ◽

Modal Parameters ◽

Frequency Range ◽

Case Examples ◽

Measured Frequency Response ◽

Damping Loss Factor

Abstract A new method for the estimation of modal parameters is presented in this paper. Unlike the majority of the existing methods which involve complicated curve fitting and interpolative procedures, the proposed method calculates the modal parameters by solving eigenvalue problem of an equivalent eigensystem derived from measured frequency response function (FRF) data. It is developed based on the practical assumption that only one incomplete column of the FRF matrix of the test structure has been measured in a frequency range of interest. All the measured FRFs are used simultaneously to construct the equivalent eigensystem matrices from which natural frequencies, damping loss factor and modeshape vectors of interest can be directly solved. Since the identification problem is reduced to an eigenvalue problem of an equivalent system, natural frequencies and damping loss factors identified are consistent. Further procedures for normalizing the identified eigenvectors so that they become mass-normalized are developed. Numerical case examples are given to demonstrate the practicality of the proposed method and results obtained are indeed very promising. It is believed that with the availability of such identification method, modal analysts’ dream of intelligent and full automatic modal analysis will become a reality.

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