Effects of Temperature, End-Conditions, Flow, and Branching on the Frequency Response of Pneumatic Lines

1972 ◽  
Vol 94 (1) ◽  
pp. 15-20 ◽  
Author(s):  
M. E. Franke ◽  
A. J. Malanowski ◽  
P. S. Martin
Keyword(s):  
Frequency Response ◽  
Experimental Results ◽  
Distributed Parameter ◽  
Transmission Line Theory ◽  
Amplitude Frequency Response ◽  
End Conditions ◽  
Line Theory ◽  
Effects Of Temperature ◽  
Different Diameters ◽  
Signal Sinusoïdal

Experimental results are presented to show the effects of temperature, flow, end-conditions, and branching on the small-signal sinusoidal amplitude frequency response of pneumatic lines. Distributed parameter transmission line theory for uniform lines is extended to include varying conditions of pressure and temperature along the line as well as series-connected lines of different diameters and parallel branching. The experimental results are compared with the formulated theory for several test configurations. Agreement between experiment and computer solutions based on the theory is relatively good.

Frequency Response of Blocked Annular Fluid Transmission Lines

1981 ◽  
Vol 103 (4) ◽  
pp. 366-369
Author(s):  
M. E. Franke ◽  
G. R. Farney ◽  
E. F. Moore
Keyword(s):  
Transmission Line ◽  
Frequency Response ◽  
Transmission Lines ◽  
Transmission Line Theory ◽  
Line Theory ◽  
Theory And Experiment

Frequency response measurements on blocked annular pneumatic transmission lines with five different radius ratios have been obtained and compared with annular transmission line theory. The agreement between theory and experiment was good.

Vibration Characteristics of Rotating Thin Disks—Part I: Experimental Results

2012 ◽  
Vol 79 (4) ◽  
Author(s):  
Ramin M. H. Khorasany ◽  
Stanley G. Hutton
Keyword(s):  
Frequency Response ◽  
Natural Frequency ◽  
Linear Theory ◽  
Lateral Force ◽  
Vibration Characteristics ◽  
Experimental Results ◽  
Rotating Disks ◽  
Critical Speeds ◽  
Applied Forces ◽  
Thin Disks

Analysis of the linear vibration characteristics of unconstrained rotating isotropic thin disks leads to the important concept of “critical speeds.” These critical rotational speeds are of interest because they correspond to the situation where a natural frequency of the rotating disk, as measured by a stationary observer, is zero. Such speeds correspond physically to the speeds at which a traveling circumferential wave, of shape corresponding to the mode shape of the natural frequency being considered, travel around the disk in the absence of applied forces. At such speeds, according to linear theory, the blade may respond as a space fixed stationary wave and an applied space fixed dc force may induce a resonant condition in the disk response. Thus, in general, linear theory predicts that for rotating disks, with low levels of damping, large responses may be encountered in the region of the critical speeds due to the application of constant space fixed forces. However, large response invalidates the predictions of linear theory which has neglected the nonlinear stiffness produced by the effect of in-plane forces induced by large displacements. In the present paper, experimental studies were conducted in order to measure the frequency response characteristics of rotating disks both in an idling mode as well as when subjected to a space fixed lateral force. The applied lateral force (produced by an air jet) was such as to produce displacements large enough that non linear geometric effects were important in determining the disk frequencies. Experiments were conducted on thin annular disks of different thickness with the inner radius clamped to the driving arbor and the outer radius free. The results of these experiments are presented with an emphasis on recording the effects of geometric nonlinearities on lateral frequency response. In a companion paper (Khorasany and Hutton, 2010, “Vibration Characteristics of Rotating Thin Disks—Part II: Analytical Predictions,” ASME J. Mech., 79(4), p. 041007), analytical predictions of such disk behavior are presented and compared with the experimental results obtained in this study. The experimental results show that in the case where significant disk displacements are induced by a lateral force, the frequency characteristics are significantly influenced by the magnitude of forced displacements.

scholarly journals Effect Factors of Benzene Adsorption and Degradation by Nano-TiO2Immobilized on Diatomite

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Lijun Cheng ◽  
Yong Kang ◽  
Guishui Li
Keyword(s):  
Relative Humidity ◽  
Light Intensity ◽  
Experimental Results ◽  
Benzene Adsorption ◽  
Effect Factors ◽  
Benzene Concentration ◽  
Effects Of Temperature ◽  
Safe Concentration

Difference between adsorption of benzene by diatomite and nano-TiO2immobilized on diatomite was investigated. And effects of temperature, light intensity, relative humidity, and initial benzene concentration on adsorption and degradation of benzene by nano-TiO2immobilized on diatomite were also studied. The experimental results showed that when initial benzene concentration was2.2×10−3 mg L−1, it could be degraded to below safe concentration (1.1×10−4 mg L−1) after 50 h when temperature was 20°C, but it just needed 30 h at 35°C. When light intensity was 6750 Lx, it needed 30 h for benzene to be degraded to below safe concentration, but benzene could barely be degraded without light. When relative humidity was 50%, benzene could be degraded to1.0×10−4 mg L−1after 30 h, while its concentration could be reduced to7.0×10−5 mg L−1at the relative humidity of 80%.

scholarly journals The Investigation of Effects of Temperature and Nanoparticles Volume Fraction on the Viscosity of Copper Oxide-ethylene Glycol Nanofluids

2017 ◽  
Author(s):  
Mohammad Hemmat Esfe
Keyword(s):  
Ethylene Glycol ◽  
Copper Oxide ◽  
Volume Fraction ◽  
Relative Viscosity ◽  
Experimental Results ◽  
Different Temperatures ◽  
Nanoparticles Volume Fraction ◽  
Effects Of Temperature ◽  
Nanofluid Viscosity ◽  
Experimental Values

In the present article, the effects of temperature and nanoparticles volume fraction on the viscosity of copper oxide-ethylene glycol nanofluid have been investigated experimentally. The experiments have been conducted in volume fractions of 0 to 1.5 % and temperatures from 27.5 to 50 °C. The shear stress computed by experimental values of viscosity and shear rate for volume fraction of 1% and in different temperatures show that this nanofluid has Newtonian behaviour. The experimental results reveal that in a given volume fraction when temperature increases, viscosity decreases, but relative viscosity varies. Also, in a specific temperature, nanofluid viscosity and relative viscosity increase when volume fraction increases. The maximum amount of increase in relative viscosity is 82.46% that occurs in volume fraction of 1.5% and temperature of 50 °C. Some models of computing nanofluid viscosity have been suggested. The greatest difference between the results obtained from these models and experimental results was down of 4 percent that shows that there is a very good agreement between experimental results and the results obtained from these models.

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