An oscillating water column (OWC) is typical of axial rotor turbines, which are used to convert ocean wave energy into electrical energy. This device impacts downstream pressure PULSATIONs when its rotor becomes eccentric. This study compared the details of pressure PULSATIONs downstream of eccentric and non-eccentric rotors under three operating conditions: low flow A, high-efficiency flow B, and high flow C. Computational fluid dynamics (CFD) simulations based on the PULSATION tracking network (PTN) method were used for the OWC device to compare the experimental results. The results indicate downstream pressure PULSATIONs were mostly dominated by the blade frequency in non-eccentric low-flow cases. In the other eccentric operating conditions, downstream pressure PULSATIONs were mainly dominated by the 2-, 3. 6-, 6-, and 7-times rotation frequencies and the 0. 5-times blade frequency. The phase change of downstream pressure PULSATIONs in eccentric and non-eccentric conditions is consistent with the flow direction. The phase change is relatively uniform and steady before eccentricity and becomes turbulent after eccentricity, which affects its steadiness. In this study, the OWC device did not significantly change with or without rotor eccentricity at a 1-time blade frequency intensity, however, at a 1-time rotation frequency, the OWC device showed a significant increase in the pressure PULSATION amplitude after rotor eccentricity. The study of the dominant frequency, amplitude, and phase of pressure PULSATIONs in OWC devices with eccentric rotors can help prevent excessive pressure PULSATIONs that can lead to incidents.

This paper presents analysis of tall building under wind load excitation taking account of PULSATION. The path of the analysis using MatLAB, Lira and Russian national code SNiP are presented. Use of wind velocity-time graph is employed where the change in wind pressure (PULSATION) with time is assumed to be proportional to a similar change in wind velocity. Results are compared and show a conformation to dynamic behaviour of the buildings under such excitations as PULSATION, thus making the analysis adequate for assessing the dynamic behaviour of a structure.      

In this article, dynamics of the cerebrospinal fluid (CSF) was studied, using computational fluid dynamics. Using MRI images of two special cases, a 2-dimensional model of the ventricular system was made. CSF velocity and pressure distribution in ventricular system have high importance since the flow pattern of this liquid has an important effect on intracranial pressure, i.e., ICP, which has a key role in treatment of patients suffering from brain trauma. The pulsatile nature of CSF production, which is a result of arterial blood pressure in choroid plexuses, is considered for the first time.  Finite element analysis of ventricular area with CFD analyzer software was processed using ADINA 8.2. Pressure distribution in different conditions of CSF production, i.e., constant input flow rate and pulsatile input flow rate, were compared. Comparison between the simulation results and reported experimental data depicted that modeling CSF with pulsatile production nature is more realistic.

In this paper, pulsating grid-generated turbulence is studied. A two-component hot wire anemometry technique is used. The PULSATION effects on characterizing length scales and the statistical description of fluctuations are studied in comparison with their stationary counterparts. No significant change in the character of the turbulent flow with PULSATION is observed.

This article describes the results of experimental observations in pulsating Simple Shear Flows (SSF). A uniform-mean-gradient shear flow was generated within the test section of an open circuit wind tunnel. Transverse arrays of honeycomb channels with differing resistances were used to generate shear flow at low shear rates (less than 20 S-1). A set of rotating vanes pulsated the flow field at 8.5 Hz and 18 Hz. Instantaneous velocitywas measured by employing a two-component hot wire anemometry technique. The experimental credibility of the facility was established in stationary SSF. In pulsating flows the PULSATION effects on mean shear rate, the kinetic energy of turbulence, Reynolds stresses and the probability density of stream-wise velocity fluctuations were studied. It was found that deviation from stationary turbulence with PULSATION at 8.5 Hz was more significant than that at 18 Hz. The modified form of the governing equations for pulsating flows was derived. The emphasis of the analysis was placed on the production and dissipation mechanisms in pulsating SSF. The results are discussed in connection with the modified equations and physically plausible explanations are offered to interpret the laboratory observations. It is concluded that the anisotropic dissipation mechanism may be responsible for the observed experimental results.

Longitudinal dispersion of solute released in an unsteady flow between two coaxial cylinders is re-examined in the presence of first order chemical kinetics in the bulk flow. The flow unsteadiness is caused by the oscillation of the outer tube around its axis as well as by a periodic pressure gradient. Unlike some previous works, the gap width of the annular tube is used as the typical length scale which is physically meaningful to a greater extent. In order to employ the method of moment, a finite difference implicit scheme has been adopted to solve the Aris integral moment equations arising from the unsteady convective diffusion equation for all time periods. The individual and combined effects of different velocity components resulting from steady and timedependent parts of the driving forces are examined and they are identified based on their functionality. In any flow situation, wall factor is found to have a larger contribution in velocity as well as in dispersion compared to the pressure factor. The behaviour of dispersion coefficient with the variation of radius ratio, bulk flow reaction parameter, and frequency parameters have been examined. Dispersion coefficient is found to diminish with the increase of the reaction-rate in the bulk flow, whereas the effect of the radius ratio on the dispersion coefficient is fixed by the form of the velocity distribution. The axial distributions of mean concentration are approximated using Hermite polynomial representation from the first four central moments for a range of different reaction-rate parameters. It has been found that, irrespective of the flow situation, the peak of the concentration distribution decreases with the increase in reaction rate parameter.

Thyroid hormone and its metabolism have been shown to be abnormal in patients with non-thyroidal illnesses such as those with advanced heart failure. Free T3/Reverse T3 ratio is believed to be associated with a reduced ejection fraction and poor short-term outcomes in patients with advanced heart failure. We sought to evaluate the effects of Enhanced External Counter PULSATION Therapy (EECP) on the thyroid hormone profile of heart failure patients.Methods: Our study group consisted of 30 patients referred for the management of heart failure. Each patient underwent treatment by EECP, and free Triiodothyronine (T3) level alterations were monitored before the commencement of treatment and once again after the completion of standard EECP treatment.Results: Thirty patients with advanced heart failure symptoms at a median age of 65 (46-77) years were enrolled. After EECP therapy, the ejection fraction was improved significantly. The median ejection fraction after EECP treatment was 46.5% (p value<0.001). T3 levels increased to 4.01±1.46 (ng/dl); this, however, was not a significant finding (p value=0.44).Conclusion: Treatment of heart failure by EECP may have some effects on thyroid hormone milieu and metabolism insofar as T3 levels rose after EECP in our study, although this effect was not statistically significant. More thorough investigations are needed before any conclusion could be made on this matter.