Case study: Experimental characterization of noise and vibration sources in a refrigerator

The sources of noise and vibration of a refrigerator are characterized by means of laboratory measurements. Three different elements are considered: compressor, evaporator fan, and condenser fan. Both the radiated acoustic energy and the mechanical power injected to the refrigerator structure are measured. Acoustic intensity maps on the refrigerator faces at different frequencies are also provided They are helpful in visualizing the more problematic zones in terms of noise emis- sion. The devices are tested in vacuo or working inside the refrigerator. The provided information can be used as input data for vibroacoustic simulation models such as statistical energy analysis. It is also of interest in order to improve the refrigerator acoustic design.

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Analysis and experimental characterization of idle tones in 2nd-order bandpass ΣΔ modulators-a 0.8 μm CMOS switched-current case study

ISCAS 2001. The 2001 IEEE International Symposium on Circuits and Systems (Cat. No.01CH37196) ◽

10.1109/iscas.2001.922352 ◽

2002 ◽

Author(s):

J.M. de la Rosa ◽

B. Perez-Verdu ◽

F. Medeiro ◽

R. del Rio ◽

A. Rodriguez-Vazquez

Keyword(s):

Experimental Characterization ◽

Current Case ◽

Switched Current

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Experimental Characterization of the Structural Deformation of Type IV Pressure Vessels Subjected to Internal Pressure

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.809.47 ◽

2019 ◽

Vol 809 ◽

pp. 47-52 ◽

Cited By ~ 1

Author(s):

Martin Nebe ◽

Daniel Maraite ◽

Clemens Braun ◽

Daniel Hülsbusch ◽

Frank Walther

Keyword(s):

Internal Pressure ◽

Test Chamber ◽

Simulation Models ◽

Cost Effective ◽

Pressure Vessels ◽

Structural Deformation ◽

Experimental Characterization ◽

Type Iv ◽

Structural Mass

The investigations deal with the experimental characterization of the structural deformation of type IV pressure vessels subjected to internal pressure. For the widespread use of hydrogen technology in transport industries, the development of cost-effective storage systems is a crucial step. State of the art in the field of hydrogen storage are type IV pressure vessels, which consist of a polymeric liner and an enforcing winding of carbon fiber-reinforced plastic (CFRP). For the development of material-optimized and high-safety pressure vessels, the acquisition of reliable experimental data in order to validate numerical simulations is a necessity. In a specially designed test chamber subscale vessels are clamped and subjected to internal pressure. At defined pressure stages the vessel’s deformation is recorded and analyzed. Consequently, the overall structural deformation is assessed with regard to the used structural mass, the burst pressure and the resulting failure. The results can be used for structure optimization purposes as well as for the optimization of numerical simulation models.

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Experimental characterization of the deformation behavior of a gas-bearing clastic formation: soft or hard rocks? A case study

Geomechanics and Geophysics for Geo-Energy and Geo-Resources ◽

10.1007/s40948-019-00130-3 ◽

2019 ◽

Vol 6 (1) ◽

Cited By ~ 2

Author(s):

Francesco Marzano ◽

Matteo Pregliasco ◽

Vera Rocca

Keyword(s):

Deformation Behavior ◽

Experimental Characterization ◽

Soft Or ◽

Hard Rocks ◽

Gas Bearing

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Stochastic simulation and prediction of turbidity dynamics in karst systems. Case study: Mokra karst spring (SE Serbia)

Review of the Bulgarian Geological Society ◽

10.52215/rev.bgs.2021.82.3.222 ◽

2021 ◽

Vol 82 (3) ◽

pp. 222-224

Author(s):

Veljko Marinović ◽

Branislav Petrović

Keyword(s):

Stochastic Simulation ◽

Warning System ◽

Simulation Models ◽

Karst Spring ◽

Timely Response ◽

Karst Systems ◽

Groundwater Source ◽

Source Management

Characterization of a karst system includes the analysis of two components – quantitative and qualitative one. Forecasting of future values of groundwater parameters can be very useful in defining the amounts of water needed for a reliable water supply. Stochastic simulation and forecasting were carried out for time series of precipitation and Mokra karst spring turbidity recorded in 2015. Simulation models within groundwater management would have a function in the early warning system which will enable timely response of groundwater source management.

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Experimental Characterization of Static Behavior of a New GFRP–Metal Space Truss Deployable Bridge: Comparative Case Study

Journal of Bridge Engineering ◽

10.1061/(asce)be.1943-5592.0001650 ◽

2021 ◽

Vol 26 (1) ◽

pp. 05020011

Author(s):

Dongdong Zhang ◽

Jiaxin Yuan ◽

Feng Li ◽

Yaru Lv ◽

Qilin Zhao ◽

...

Keyword(s):

Comparative Case Study ◽

Experimental Characterization ◽

Static Behavior ◽

Space Truss

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Multiscale experimental characterization of coatings on ceramics: A case study of tungsten on SiC

Surface and Coatings Technology ◽

10.1016/j.surfcoat.2019.03.040 ◽

2019 ◽

Vol 367 ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

Huaxin Li ◽

Takaaki Koyanagi ◽

Xunxiang Hu ◽

Yutai Katoh

Keyword(s):

Experimental Characterization

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The Effects of Explicit versus Parameterized Convection on the MJO in a Large-Domain High-Resolution Tropical Case Study. Part I: Characterization of Large-Scale Organization and Propagation*

Journal of the Atmospheric Sciences ◽

10.1175/jas-d-12-0227.1 ◽

2013 ◽

Vol 70 (5) ◽

pp. 1342-1369 ◽

Cited By ~ 65

Author(s):

Christopher E. Holloway ◽

Steven J. Woolnough ◽

Grenville M. S. Lister

Keyword(s):

High Resolution ◽

Large Scale ◽

Propagation Speed ◽

Simulation Models ◽

Horizontal Resolution ◽

Convective Heating ◽

Convection Model ◽

Boundary Layer Scheme

Abstract High-resolution simulations over a large tropical domain (~20°S–20°N, 42°E–180°) using both explicit and parameterized convection are analyzed and compared to observations during a 10-day case study of an active Madden–Julian oscillation (MJO) event. The parameterized convection model simulations at both 40- and 12-km grid spacing have a very weak MJO signal and little eastward propagation. A 4-km explicit convection simulation using Smagorinsky subgrid mixing in the vertical and horizontal dimensions exhibits the best MJO strength and propagation speed. Explicit convection simulations at 12 km also perform much better than the 12-km parameterized convection run, suggesting that the convection scheme, rather than horizontal resolution, is key for these MJO simulations. Interestingly, a 4-km explicit convection simulation using the conventional boundary layer scheme for vertical subgrid mixing (but still using Smagorinsky horizontal mixing) completely loses the large-scale MJO organization, showing that relatively high resolution with explicit convection does not guarantee a good MJO simulation. Models with a good MJO representation have a more realistic relationship between lower-free-tropospheric moisture and precipitation, supporting the idea that the moisture–convection feedback is a key process for MJO propagation. There is also increased generation of available potential energy and conversion of that energy into kinetic energy in models with a more realistic MJO, which is related to larger zonal variance in convective heating and vertical velocity, larger zonal temperature variance around 200 hPa, and larger correlations between temperature and ascent (and between temperature and diabatic heating) between 500 and 400 hPa.

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