TEST-CASE NO 16: IMPACT OF A DROP ON A THIN FILM OF THE SAME LIQUID (PE, PA)

2004 ◽  
Vol 16 (1-3) ◽  
pp. 105-109
Author(s):  
F. Pigeonneau ◽  
Francois Feuillebois
Keyword(s):  
Thin Film ◽  
Test Case

Advanced Bulge Test System

1997 ◽  
Vol 505 ◽  
Author(s):  
H. Keiner ◽  
F. J. von Preissig ◽  
H. Zeng ◽  
M. N. G. Nejhad ◽  
E. S. Kim
Keyword(s):  
Thin Film ◽  
Elastic Stiffness ◽  
Test System ◽  
Bulge Test ◽  
Testing System ◽  
Test Case ◽  
Established Method ◽  
Bulge Testing ◽  
Speed Accuracy ◽  
Key Innovations

ABSTRACTThe bulge test is an established method of measuring the residual stress and elastic stiffness of thin-film materials. We present an advanced experimental bulge-testing system that provides advantages in speed, accuracy, and flexibility. Key innovations include the use of a Laser Doppler Displacement Meter to measure deflection, an actuated air-cylinder mechanism to vary pressure, and sophisticated computer handling of data acquisition and analysis. A test case demonstrates that repeatability of results is extremely good.

Comparison of Thin Film Heat Flux Gauge Technologies Emphasizing Continuous-Duration Operation

2019 ◽  
Author(s):  
Shawn Siroka ◽  
Reid A. Berdanier ◽  
Karen A. Thole ◽  
Kam S. Chana ◽  
Charles W. Haldeman ◽  
...  
Keyword(s):  
Thin Film ◽  
Heat Flux ◽  
Thermal Properties ◽  
Short Duration ◽  
Reynolds Numbers ◽  
Calibration Method ◽  
Test Facility ◽  
Test Case ◽  
Reference Device ◽  
Steady Heat

Abstract Thin film heat flux gauges (HFGs) have been used for several decades to measure surface temperatures and heat flux in test turbines with the majority being used in facilities that are short-duration. These gauges are typically composed of two resistive temperature devices deposited on opposing sides of a dielectric. However, because these sensors have been traditionally applied for measurements in short-duration, transient-type facilities, the challenges facing adaptation of this technology for a continuous-duration steady facility warrant investigation. Those challenges are highlighted, and solutions are presented throughout the paper. This paper describes the nanofabrication process for heat flux gauges and a new calibration method to address potential deterioration of gauges over long runtimes in continuous-duration facilities. Because a primary uncertainty of these sensors arises from the ambiguity of the thermal properties, special emphasis is placed on the property determination and potential errors due to improper thermal properties. Also, this paper presents a discussion on the use of impulse response theory to process the data showing the feasibility of the method for steady-duration facilities after an initial settling time. The latter portion of the paper focuses on comparing well-established heat flux gauges developed for short-duration turbine test facilities to recently developed gauges fabricated using modern nanofabrication techniques for a continuous turbine test facility. Using a commercially available heat flux gauge, capable of measuring a steady heat flux as a reference, the gauges were compared using the test case of an impinging jet over a range of Reynolds numbers. The comparison between the PSU gauge and the reference device indicated agreement within 14%, and similar results were achieved through comparison with established sensors from partner institutions.

Specifying and Benchmarking a Thin Film Model for Oil Systems Applications in ANSYS Fluent

2012 ◽  
Author(s):  
C. Wang ◽  
H. P. Morvan ◽  
S. Hibberd ◽  
K. A. Cliffe ◽  
A. Anderson ◽  
...  
Keyword(s):  
Thin Film ◽  
Film Flow ◽  
Test Case ◽  
Thin Film Flow ◽  
Ansys Fluent ◽  
Film Model ◽  
Thin Film Model ◽  
Software Product ◽  
Aero Engine ◽  
Engine Bearing

A thin film model developed for calculating the oil film flow in aero-engine bearing chamber is described. The performance of the model, which has been implemented in the commercial computational fluid dynamics software product: ANSYS Fluent, is benchmarked by comparing the computational results obtained from a Nottingham UTC in-house code and a development version of Fluent. Both codes are used to solve thin film flow in a test case configuration and based on the same finite area method. With identified constraints, the two implementations agree well.

scholarly journals Comparison of Thin Film Heat Flux Gauge Technologies Emphasizing Continuous-Duration Operation

2020 ◽  
Vol 142 (9) ◽  
Author(s):  
Shawn Siroka ◽  
Reid A. Berdanier ◽  
Karen A. Thole ◽  
Kam Chana ◽  
Charles W. Haldeman ◽  
...  
Keyword(s):  
Thin Film ◽  
Heat Flux ◽  
Thermal Properties ◽  
Impulse Response ◽  
Short Duration ◽  
Reynolds Numbers ◽  
Calibration Method ◽  
Test Facility ◽  
Test Case ◽  
Reference Device

Abstract Thin-film heat flux gauges (HFGs) have been used for decades to measure surface temperatures and heat flux in test turbines with the majority being used in facilities that are short-duration. These gauges are typically composed of two resistive temperature devices deposited on opposing sides of a dielectric. However, because these sensors have been traditionally applied for measurements in transient-type facilities, the challenges facing adaptation of this technology for a steady facility warrant investigation. These challenges are highlighted, and the solutions are presented throughout the paper. This paper describes the nanofabrication process for heat flux gauges and a new calibration method to address the potential deterioration of gauges over long runtimes in continuous-duration facilities. Because the primary uncertainty of these sensors arises from the ambiguity of the thermal properties, the emphasis is placed on the property determination. Also, this paper presents a discussion on the use of impulse response theory to process the data showing the feasibility of the method for steady-duration facilities after an initial settling time. The latter portion of the paper focuses on comparing well-established heat flux gauges developed for short-duration turbine test facilities to recently developed gauges fabricated using modern nanofabrication techniques for a continuous turbine test facility. The gauges were compared using the test case of an impinging jet over a range of Reynolds numbers. The comparison between the PSU gauge and the reference device indicated agreement within 14%, and similar results were achieved through comparison with established sensors from partner institutions.

Experimental Measurement of Multiple Thermal Properties by Error Minimization

2007 ◽  
Author(s):  
Brian Smith ◽  
Cristina Amon
Keyword(s):  
Thin Film ◽  
Phase Measurement ◽  
Measurement Techniques ◽  
Heat Diffusion ◽  
Test Case ◽  
Temperature Phase ◽  
Error Minimization ◽  
Thermal Tests ◽  
System Variable ◽  
Transient Heat Diffusion

Common thin film thermometry techniques are usually based on transient heat diffusion within a sample and its surroundings and are therefore sensitive to the film’s thermal conductivity (k) and heat capacity (C). This presents a problem of under-constraint in the numerical fitting models when both k and C of a given film are unknown. A number of approaches and assumptions have been studied to eliminate this dual dependence or estimate C analytically. However, they often amount to little more than fitting parameters, experimental assumptions, and rough estimates for many composite and polymer films that are emerging in the microelectronics and MEMS industries. The effect that the uncertainty in one property has on the prediction of the other is discussed in the framework of the polymer film PVDF used in many microsensor and actuator applications. An error surface analysis is used to describe the link between assumption and prediction for thermoreflectance and temperature phase measurement techniques. A methodology is presented that combines the results of two thermal tests through an error minimization algorithm to solve for both k and C with no analytical assumptions or approximations. This approach is demonstrated with an experimental test case, validated with synthesized data, and generalized to any system variable and a multitude of thin film thermometry variable or thin film thermometry technique.

Clean Electron Microscope Substrate Films Used for Micrometeorite Collection and Study

1967 ◽  
Vol 25 ◽  
pp. 366-367
Author(s):  
D. M. Davies ◽  
R. Kemner ◽  
E. F. Fullam
Keyword(s):  
Thin Film ◽  
Electron Microscope ◽  
High Altitude ◽  
Amyl Acetate ◽  
Temperature Variations ◽  
Film Forming ◽  
Film Specimen ◽  
Particulate Contaminants

All serious electron microscopists at one time or another have been concerned with the cleanliness and freedom from artifacts of thin film specimen support substrates. This is particularly important where there are relatively few particles of a sample to be found for study, as in the case of micrometeorite collections. For the deposition of such celestial garbage through the use of balloons, rockets, and aircraft, the thin film substrates must have not only all the attributes necessary for use in the electron microscope, but also be able to withstand rather wide temperature variations at high altitude, vibration and shock inherent in the collection vehicle's operation and occasionally an unscheduled violent landing.Nitrocellulose has been selected as a film forming material that meets these requirements yet lends itself to a relatively simple clean-up procedure to remove particulate contaminants. A 1% nitrocellulose solution is prepared by dissolving “Parlodion” in redistilled amyl acetate from which all moisture has been removed.

Microtomy of spherical Al2O3 powders

1983 ◽  
Vol 41 ◽  
pp. 74-75
Author(s):  
E.J. Jenkins ◽  
D.S. Tucker ◽  
J.J. Hren
Keyword(s):  
Thin Film ◽  
Size Range ◽  
Particle Aggregation ◽  
Ion Milling ◽  
Thin Sections ◽  
Α Phase ◽  
Convenient Means ◽  
Van Der Waals Attraction ◽  
Negative Feature ◽  
Film Substrate

The size range of mineral and ceramic particles of one to a few microns is awkward to prepare for examination by TEM. Electrons can be transmitted through smaller particles directly and larger particles can be thinned by crushing and dispersion onto a substrate or by embedding in a film followed by ion milling. Attempts at dispersion onto a thin film substrate often result in particle aggregation by van der Waals attraction. In the present work we studied 1-10 μm diameter Al2O3 spheres which were transformed from the amprphous state to the stable α phase.After the appropriate heat treatment, the spherical powders were embedded in as high a density as practicable in a hard EPON, and then microtomed into thin sections. There are several advantages to this method. Obviously, this is a rapid and convenient means to study the microstructure of serial slices. EDS, ELS, and diffraction studies are also considerably more informative. Furthermore, confidence in sampling reliability is considerably enhanced. The major negative feature is some distortion of the microstructure inherent to the microtoming operation; however, this appears to have been surprisingly small. The details of the method and some typical results follow.

Studies on Water in the Hydration Chamber of a Modified Electron Microscope

1970 ◽  
Vol 28 ◽  
pp. 544-545
Author(s):  
R. C. Moretz ◽  
G. G. Hausner ◽  
D. F. Parsons
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Electron Microscope ◽  
Steady State ◽  
Room Temperature ◽  
Small Mass ◽  
Equilibrium Pressure ◽  
Biological Objects ◽  
Mechanical Pump ◽  
Differential Pumping

Use of the electron microscope to examine wet objects is possible due to the small mass thickness of the equilibrium pressure of water vapor at room temperature. Previous attempts to examine hydrated biological objects and water itself used a chamber consisting of two small apertures sealed by two thin films. Extensive work in our laboratory showed that such films have an 80% failure rate when wet. Using the principle of differential pumping of the microscope column, we can use open apertures in place of thin film windows.Fig. 1 shows the modified Siemens la specimen chamber with the connections to the water supply and the auxiliary pumping station. A mechanical pump is connected to the vapor supply via a 100μ aperture to maintain steady-state conditions.

Imaging of platinum-shadowed macromolecular complexes in dark field

1984 ◽  
Vol 42 ◽  
pp. 146-147
Author(s):  
D.W. Andrews ◽  
F.P. Ottensmeyer
Keyword(s):  
Thin Film ◽  
Three Dimensional ◽  
Average Diameter ◽  
Dark Field ◽  
Bright Field ◽  
Field Mode ◽  
Macromolecular Complexes ◽  
Average Mass ◽  
Topological Features ◽  
Projection Images

Shadowing with heavy metals has been used for many years to enhance the topological features of biological macromolecular complexes. The three dimensional features present in directionaly shadowed specimens often simplifies interpretation of projection images provided by other techniques. One difficulty with the method is the relatively large amount of metal used to achieve sufficient contrast in bright field images. Thick shadow films are undesirable because they decrease resolution due to an increased tendency for microcrystalline aggregates to form, because decoration artefacts become more severe and increased cap thickness makes estimation of dimensions more uncertain.The large increase in contrast provided by the dark field mode of imaging allows the use of shadow replicas with a much lower average mass thickness. To form the images in Fig. 1, latex spheres of 0.087 μ average diameter were unidirectionally shadowed with platinum carbon (Pt-C) and a thin film of carbon was indirectly evaporated on the specimen as a support.

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