Wavy Aspects in a Precessed Cylindrical Open Channel
Issue:
Volume 7, Issue 3, September 2021
Pages:
22-26
Received:
24 October 2021
Accepted:
15 November 2021
Published:
23 November 2021
Abstract: In this letter some experimental and theoretical results from the flow in open cylindrical channel under precession conditions are reported. This includes the linear solutions of velocity field based on real experimental observations, and the nonlinear solution where a new weakly nonlinear KdV model equation is derived and solved numerically, this was compared with the real single Kelvin mode of the problem that appears in a symmetrical form with constant speed. The paper also shades the light on the instability features, mainly the wave breaking of single Kelvin mode, that is considered the resonance case of the problem, a new instability diagram in terms of Strouhal and Reynolds numbers is presented for the different cases reported from the experiment. The measurements of the mean azimuthal flow have been carried out using particle tracking procedure that enabled us finally to extract equation fit connects between the control parameters of the problem (which are the water volume, the angle of tilt and rotation rate) and the drift velocity the results pours in favor of the ADV measurements extracted in the previous work, and show that the mean flow increases by increasing both the tilt and the rotation rate where the instability features in the system appear at earlier levels, while increasing the water volume needs more energy to get the flow instability.
Abstract: In this letter some experimental and theoretical results from the flow in open cylindrical channel under precession conditions are reported. This includes the linear solutions of velocity field based on real experimental observations, and the nonlinear solution where a new weakly nonlinear KdV model equation is derived and solved numerically, this ...
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Studies on Characterisation of SBS Polymer Modified and Neat Bituminous Mixes Using Warm Mix Asphalt for Paving Applications
Awanti S. S.,
Anilkumar L.
Issue:
Volume 7, Issue 3, September 2021
Pages:
27-52
Received:
3 June 2021
Accepted:
3 September 2021
Published:
23 November 2021
Abstract: With increasing concerns of global warming and increasing exhausation of gases, the asphalt industry looking for alternative for hot mix asphalt (HMA). Warm mix asphalt (WMA) is a fast emerging new technology which has a potential of revolutionalizing the production of asphalt mixtures. WMA technology allows the mixing, lay down and compaction of asphalt mixes at significantly lower temperatures compared to hot mix asphalt (HMA). The technology can reduce production temperatures by as much as 30 percent. Asphalt mixes are generally produced at 150°C or greater temperatures depending mainly on type of binder used. WMA mixes can be produced at temperatures of about 120°C or lower. In this study an attempt has been made to compare HMA (VG-30 and WMA (SBS-PMB-40) with organic additives (Zycotherm, Sasobit and Evotherm) with various dosages on Marshall properties for Dense Bituminous Macadam (DBM), Grade-2. the adopted mixing temperatures for HMA was 155°C, 130°C, and 120°C and mixing temperature for WMA was 130°C and 120°C. The laboratory study concludes that stability and Marshall properties for WMA mix were improved by addition of additives.
Abstract: With increasing concerns of global warming and increasing exhausation of gases, the asphalt industry looking for alternative for hot mix asphalt (HMA). Warm mix asphalt (WMA) is a fast emerging new technology which has a potential of revolutionalizing the production of asphalt mixtures. WMA technology allows the mixing, lay down and compaction of a...
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