Experimental study on flow over arced-plan porous weirs

Unlike conventional impermeable weirs, porous weirs without clogging the flow and passage of aquatic life with increased aeration and aerobic reactions with minimal negative effects on the environment are known as environmentally friendly structures. This study experimentally investigates the hydraulic performance of Arced-Plan Porous Weirs (APPWs) in different hydraulic and geometric conditions. For this purpose, four different porous and two solid weirs were examined. Experiments were conducted in a horizontal laboratory flume with length, width, and height of 20, 0.6, and 0.5 m, respectively, for a wide range of flow rates, particle sizes, and three arc lengths. Results showed that increasing filling material sizes increases the free discharge coefficient and reduces the submerged Discharge Reduction Factor (DRF). It was also concluded that the weirs’ effective length significantly impacts the free discharge coefficient and has no significant effect on the threshold submergence index and submerged DRF. Unlike solid weirs, the threshold submergence of porous weirs occurs at a downstream depth lower than the weir's height. Finally, according to the dimensional analysis and Gene-Expression Programming (GEP) approach, three relations were extracted to calculate the free discharge coefficient, threshold submergence index, and submerged discharge reduction factor for APPWs.

Numerical study of a case of the free discharge of water through the turbine with a braked runner

The paper presents a numerical study of the free discharge of water through the turbine with a braked runner. The simulation was carried out for a unit of a full-scale Francis turbine. The finite volume method was employed for unstructured meshes using the DES method. The simulation results show the flow structures, integral characteristics, and pressure pulsations in the flow path. The analysis of the applicability of this approach to real conditions is carried out.

Granular internal dynamics in a silo discharged with a conveyor belt

The dynamics of granular media within a silo in which the grain velocities are controlled by a conveyor belt has been experimentally investigated. To this end, the building of coarse-grained field maps of different magnitudes has allowed a deep analysis of the flow properties as a function of two parameters: the orifice size and the belt velocity. First, the internal dynamics of the particles within the silo has been fully characterized by the solid fraction, the velocity of the particles and the kinetic stress. Then, the analysis of the vertical profiles of the same magnitude (plus the acceleration) has allowed connection of the internal dynamics with the flow rate. In particular, we show that the gamma parameter – which accounts for the integration of the normalized acceleration along the vertical direction – can successfully discriminate the kind of flow established within the silo (from the quasistatic regime to the free discharge) depending on the outlet size and belt velocity.

Free Discharge of Subsurface Drainage Effluent: An Alternate Design of the Surface Drain System in Pakistan

In Pakistan, many subsurface (SS) drainage projects were launched by the Salinity Control and Reclamation Project (SCARP) to deal with twin problems (waterlogging and salinity). In some cases, sump pumps were installed for the disposal of SS effluent into surface drainage channels. Presently, sump pumps have become dysfunctional due to social and financial constraints. This study evaluates the alternate design of the Paharang drainage system that could permit the discharge of the SS drainage system in the response of gravity. The proposed design was completed after many successive trials in terms of lowering the bed level and decreasing the channel bed slope. Interconnected MS-Excel worksheets were developed to design the L-section and X-section. Design continuity of the drainage system was achieved by ensuring the bed and water levels of the receiving drain were lower than the outfalling drain. The drain cross-section was set within the present row with a few changes on the service roadside. The channel side slope was taken as 1:1.5 and the spoil bank inner and outer slopes were kept as 1:2 for the entire design. The earthwork was calculated in terms of excavation for lowering the bed level and increasing the drain section to place the excavated materials in a specific manner. The study showed that modification in the design of the Paharang drainage system is technically admissible and allows for the continuous discharge of SS drainage effluent from the area.

Physical - chemical interaction of injection waters with depleted gas formations

In order that the physical - chemical interaction of the injection water with the porous-permeable or fissured medium of reservoirs do not lead to their degradation, it is necessary that the waters to meet a number of quality conditions. The treatment and conditioning of the injectable waters is imperative to do so due to the fact that their provenance is different, such as reservoir waters, wastewater resulting from various operations – petroleum operations, meteoric waters, etc. and, in particular, due to the very large volumes of injected water. Failure to follow the steps associated with the water treatment process inevitably leads to premature reduction of the injection wells receptivity. This aspect, as well as another, will be analysed in the context of this article. The injection of water in different geological formations, usually highly depleted, is a connected and defining one in the process of extraction of natural gas from reservoirs. The claim is based on the fact that the very large volumes of reservoir water taken from natural gas stream must be stored safely, otherwise their free discharge would create a real ecological catastrophe

Effect of a stepwise opioid-sparing analgesic protocol on in-hospital oxycodone use and discharge prescription after cesarean delivery

IntroductionOpioid exposure during hospitalization for cesarean delivery increases the risk of new persistent opioid use. We studied the effectiveness of stepwise multimodal opioid-sparing analgesia in reducing oxycodone use during cesarean delivery hospitalization and prescriptions at discharge.MethodsThis retrospective cohort study analyzed electronic health records of consecutive cesarean delivery cases in four academic hospitals in a large metropolitan area, before and after implementation of a stepwise multimodal opioid-sparing analgesic computerized order set coupled with provider education. The primary outcome was the proportion of women not using any oxycodone during in-hospital stay (‘non-oxycodone user’). In-hospital secondary outcomes were: (1) total in-hospital oxycodone dose among users, and (2) time to first oxycodone pill. Discharge secondary outcomes were: (1) proportion of oxycodone-free discharge prescription, and (2) number of oxycodone pills prescribed.ResultsThe intervention was associated with a significant increase in the proportion of non-oxycodone users from 15% to 32% (17% difference; 95% CI 10 to 25), a decrease in total in-hospital oxycodone dose among users, and no change in the time to first oxycodone dose. The adjusted OR for being a non-oxycodone user associated with the intervention was 2.67 (95% CI 2.12 to 3.50). With the intervention, the proportion of oxycodone-free discharge prescription increased from 4.4% to 8.5% (4.1% difference; 95% CI 2.5 to 5.6) and the number of prescribed oxycodone pills decreased from 30 to 18 (−12 pills difference; 95% CI −11 to −13).ConclusionsMultimodal stepwise analgesia after cesarean delivery increases the proportion of oxycodone-free women during in-hospital stay and at discharge.

METHODOLOGY OF SAMPLING OF BIOLOGICAL MATERIALS FOR MICROSCOPIC METHOD OF RESEARCH IN THE OBSTETRIC-GYNECOLOGICAL PRACTICE

The article is devoted to the microscopic method of research in modern obstetrical and gynecological practice. Special attention is paid to the value of the method, the diagnostic significance of the results of the examination. There is described the preparation for the study, the purpose and methodology of the exercise. The attached photos show in detail all the stages of sampling a free discharge from the urogenital tract.