Sealed tube test method for evaluation of hermetic motor insulation performance with refrigerant systems

2002 ◽  
Author(s):  
M.G. Minnick
Keyword(s):  
Test Method ◽  
Tube Test ◽  
Insulation Performance

scholarly journals Transparent Vacuum Insulation Panels

2021 ◽  
Author(s):  
Takao Katsura
Keyword(s):  
Thermal Conductivity ◽  
Low Cost ◽  
Conductivity Measurement ◽  
Test Method ◽  
Total Thickness ◽  
Gas Barrier ◽  
Vacuum Insulation ◽  
Apparent Thermal Conductivity ◽  
Heat Flux Meter ◽  
Insulation Performance

New, low-cost transparent vacuum insulation panels (TVIPs) using structured cores for the windows of existing buildings are proposed. The TVIP is produced by inserting the structured core, the low-emissivity film, and the adsorbent into the transparent gas barrier envelopes. In this chapter, the authors introduce the outlines, the design and thermal analysis method, the performance evaluation (test) method. Firstly, five spacers, namely peek, modified peek, mesh, silica aerogel, and frame, are selected as the structured core. The effective thermal conductivity of TVIPs with five different spacers is evaluated at different pressure levels by applying numerical calculation. The result indicated that TVIPs with frame and mesh spacers accomplish better insulation performance, with a center-of-panel apparent thermal conductivity of 7.0 × 10−3 W/m K at a pressure of 1 Pa. The apparent thermal conductivity is the same as the value obtained by the simultaneous evacuation thermal conductivity measurement applying the heat flux meter method. Furthermore, using a frame-type TVIP with a total thickness of 3 mm attached to an existing window as a curtain decreases the space heat loss by approximately 69.5%, whereas the light transparency decreases to 75%.

scholarly journals DAYA ANTIBAKTERI EKSTRAK ETANOL DAUN SENGGANI (Melastoma affine D. Don)

Biomedika ◽  
2014 ◽  
Vol 6 (2) ◽  
Author(s):  
Ika Trisharyanti Dian Kusumowati ◽  
Rosita Melannisa ◽  
Angga Prasetyawan
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Mobile Phase ◽  
Ethanolic Extract ◽  
Test Method ◽  
Dilution Method ◽  
Tube Test ◽  
Inhibition Concentration ◽  
Layer Chromatography ◽  
Chloroform Methanol

Melastoma affine D. Don had some activities such as anthelmintic, antibacteria, antiinfiammation, antifungal, and antitumor. The aims of this research was determine antibacteria activity of ethanolic extract of Melastoma affine D. Don. The antimicrobial activity was tested by solid dilution method to get Minimum Inhibition Concentration (MIC). The compounds in Melastoma affine D. Don was analyzed by tube test method and Thin Layer Chromatography (TLC) with chloroform : methanol : formic acid (8,5:1,5:0,5) as mobile phase and silica gel GF254 as stationary phase. The result showed ethanolic extract of Melastoma affine D. Don contains alkaloid, polyphenol, fiavonoid, saponin, and essential oil. The MIC of Senggani against Staphylococcus aureus was 2% and 3% against Escherichia coli and the extract could not inhibit Staphylococcus aureus and Escherichia coli multiresistant until concentration 7% extract ethanol.Keywords: Melastoma affine D. Don, Staphylococcus aureus, Escherichia coli

scholarly journals Investigating the Effect of Dimension Parameters on Sound Transmission Losses in Nomex Honeycomb Sandwich

2020 ◽  
Vol 10 (9) ◽  
pp. 3109 ◽  
Author(s):  
Da Wang ◽  
Suchao Xie ◽  
Zhejun Feng ◽  
Xiang Liu ◽  
Yingli Li
Keyword(s):  
High Frequency ◽  
Transmission Loss ◽  
Sound Transmission ◽  
Layered Structures ◽  
Test Method ◽  
Core Material ◽  
Impedance Tube ◽  
Tube Test ◽  
Honeycomb Sandwich ◽  
Nomex Honeycomb

In this study, an impedance tube test was performed to explore the influence of various dimension parameters of Nomex honeycomb sandwich core material on sound transmission loss (STL). The parameters investigated included the size of the honeycomb cells and thickness of the face sheets and honeycomb cores, and the effects of single- and double-layered sandwich structures were also explored. The boundary element and finite element methods were used to simulate test results. The results show that the size of the honeycomb cells has an insignificant effect on STL. Increasing the thickness of face sheets can move the STL valley point of the material at high frequency (around 5 kHz) in the low-frequency direction and increase the STL in parts of the high frequency band. Increasing the thickness of the honeycomb core can improve STL, on the whole, but the magnitude of the improvement effect becomes weakened after the thickness of the core reaches 30 mm. The STL of double-layered structures was found to be superior to that of the single-layered structures. The simulations reveal that the trends in the STL curves of the honeycomb sandwich panels are influenced by the structural mode of the panels, and are related to the resonance of the materials. The results and relevant conclusions obtained through the above research verify that the law of influence of the structure dimension parameters on the STL measured by the impedance tube is similar to that of the large panel. This can provide a reference for the application of the impedance tube test method in structural noise reduction design.

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