Showing papers on "Diffuser (sewage) published in 2016"

Optimum aerodynamic design for wind-lens turbine

Abstract: An optimum aerodynamic design method has been developed for the wind-lens turbine. The wind-lens turbine has a brimmed diffuser around a turbine rotor, which is referred to as wind-lens. The wind-lens can achieve the wind concentration on the turbine rotor, resulting in the significant enhancement of the turbine output. The present design method is based on a quasi-three-dimensional aerodynamic design method and a genetic algorithm. The quasi-three-dimensional design consists of two parts: a meridional viscous flow analysis and two-dimensional blade element designs. In the meridional viscous flow analysis, the axisymmetric Reynolds-averaged Navier-Stokes equations are numerically solved on a meridional plane to determine the wind flow rate through the wind-lens and the spanwise flow distribution at the rotor. The turbine rotor blade geometry is determined by the two-dimensional blade element theory based on the momentum theorem of the ducted turbine. The turbine rotor and wind-lens are simultaneously optimized by the present design method. Aerodynamic performance and flow fields in the optimum and conventional design cases have been investigated by wind tunnel tests and three-dimensional Reynolds-averaged Navier-Stokes simulations, in order to verify the effectiveness of the present design method. It is found that the optimum design case achieves the significant improvement in the output power coefficient, so that its numerical and experimental results of the output power coefficient exceed the Betz limit, which is the theoretical maximum output power coefficient for bare wind turbines. It is revealed that the aerodynamic matching between the turbine rotor and the wind-lens is essential to the performance enhancement of the wind-lens turbine.

Determination of diffuser bubble size in computational fluid dynamics models to predict oxygen transfer in spiral roll aeration tanks

Abstract: The aeration tank is one of the most important processes in the biological wastewater treatment and water reuse system to remove organic pollutants in wastewater. The prediction of oxygen transfer using the computational fluid dynamics (CFD) method is crucial for minimizing the energy consumption of the aeration tank, which is one of the highest energy consuming units in a wastewater treatment system. Bubble size (dB), which is a critical parameter in the CFD simulations, was investigated for different types of diffusers. CFD calculations were conducted to simulate the hydraulics in different aeration tanks and the calculated values of the volumetric oxygen mass transfer coefficient (KLa) were compared with experimentally measured data. A total of 19 tanks containing clean water and 8 tanks containing wastewater with different diffuser types and aeration intensities were simulated. The KLa values determined for these configurations were fitted using a calibrated dB value specified in the CFD simulations. The results of the calculations indicate that the coarse-bubble diffusers, fine-pore diffusers, and slitted membrane diffusers have bubble sizes of 7–8 mm, 5–6 mm, and approximately 3 mm, respectively. Additionally, CFD simulations were conducted to simulate the flow pattern and calculate the corresponding KLa value when the diffuser configuration was changed.

VCSELs and VCSEL arrays designed for improved performance as illumination sources and sensors

Abstract: A VCSEL package including a VCSEL, a housing, containing the VCSEL, and a diffuser operably attached to the housing and configured to receive an emitted beam of light from the VCSEL and produce a beam of predetermined angular divergence. The housing may be a PLLC package, a ceramic package, or a TO-style package. The diffuser could be a substantially planar diffuser sheet, which in some cases may be comprised of glass or plastic. In some embodiments, the diffuser could be a diffractive optical element or holographic light shaping diffuser. In some embodiments, the diffuser can be designed to produce a beam with an illumination full angle of up to about 90 degrees.

Comparing Different Schemes of Agricultural Wastewater Lagooning: Depuration Performance and Microbiological Characteristics

Abstract: Since the number of factors influencing depuration efficiency and energy requirement is high, the choice of the most suitable aeration scheme in aerated lagooning systems treating agricultural wastewater is a difficult task. This study provides technicians and researchers with guidelines on air diffuser position, presence of inoculum and characteristics of microbial mass, focusing organic matter degradation and energy performance of aerated ponds treating citrus processing wastewater. Four experimental batch tanks were set up: three tanks were subject to low air flow rates and times, while a fourth tank was not aerated. The organic matter degradation in the aerated tanks was on average six times higher compared to the non-aerated tank. Positioning the air diffuser at mid-depth and consequent separation of tank contents into two layers determined a decrease in the depuration performance, presumably due to the reduced transfer of oxygen to wastewater. Although the ability of spontaneous microflora to adapt to essential oil concentrations up to 1400 mL L−1 was detected, the effect of inoculum (50% of wastewater with spontaneous microflora already adapted to high essential oil concentration) was not noticeable. Overall, the results of the investigation confirm the suitability of aerated lagoons subject to fine bubble aeration also for agricultural wastewater depuration.

A survey of biofilms on wastewater aeration diffusers suggests bacterial community composition and function vary by substrate type and time.

Abstract: Aeration diffusers in wastewater treatment plants generate air bubbles that promote mixing, distribution of dissolved oxygen, and microbial processing of dissolved and suspended matter in bulk solution. Biofouling of diffusers represents a significant problem to wastewater treatment plants because biofilms decrease oxygen transfer efficiency and increase backpressure on the blower. To better understand biofouling, we conducted a pilot study to survey the bacterial community composition and function of biofilms on different diffuser substrates and compare them to those in the bulk solution. DNA was extracted from the surface of ethylene-propylene-diene monomer (EPDM), polyurethane, and silicone diffusers operated for 15 months in a municipal treatment plant and sampled at 3 and 9 months. The bacterial community composition and function of the biofilms and bulk solution were determined by amplifying the 16S rRNA genes and pyrosequencing the amplicons and raw metagenomic DNA. The ordination plots and dendrograms of the 16S rRNA and functional genes showed that while the bacterial community composition and function of the bulk solution was independent of sampling time, the composition and function of the biofilms differed by diffuser type and testing time. For the EPDM and silicone diffusers, the biofilm communities were more similar in composition to the bulk solution at 3 months than 9 months. In contrast, the bacteria on the polyurethane diffusers were more dissimilar to the bulk solution at 3 months than 9 months. Taken together, the survey showed that the community composition and function of bacterial biofilms depend on the diffuser substrate and testing time, which warrants further elucidation.

Loadlock apparatus, cooling plate assembly, and electronic device processing systems and methods

Abstract: A loadlock apparatus including a lower disc diffuser is provided. The loadlock apparatus includes a loadlock body containing a lower loadlock chamber and an upper load loadlock chamber, a lower cooling plate in the lower loadlock chamber, and an upper cooling plate in the upper loadlock chamber. The lower disc diffuser may be centrally located above the lower cooling plate. An upper disc diffuser may be centrally located above the upper cooling plate. Systems including the loadlock apparatus and methods of operating the loadlock apparatus are provided. A cooling plate assembly that is readily removable for cleaning is also provided, as are numerous other aspects.

Ozone catalytic ozonation tower and gasified waste water treatment method utilizing same

Abstract: The embodiment of the invention discloses an ozone catalytic ozonation tower which comprises an oxidation tower body, an ozone generator, a circulating pump and a tail gas damage device, wherein the oxidation tower body comprises a first micro-porous aeration diffuser, a second micro-porous aeration diffuser, a catalyst layer, a water inlet, a water outlet, at least one oxidizing agent feeding hole, an exhaust port, a circulating water inlet and a circulating water outlet; the first micro-porous aeration diffuser is positioned at the bottom of the oxidation tower body; the second micro-porous aeration diffuser is positioned above the first micro-porous aeration diffuser; the catalyst layer is positioned above the second micro-porous aeration diffuser; the side wall of the oxidation tower body between the first micro-porous aeration diffuser and the second micro-porous aeration diffuser is sequentially provided with the water inlet and the circulating water inlet from bottom to top; the side wall of the oxidation tower body above the catalyst layer is sequentially provided with the circulating water outlet and the water outlet from bottom to top; the side wall of the oxidation tower body between the water inlet and the circulating water outlet is provided with at least one oxidizing agent feeding hole. The ozone catalytic ozonation tower is capable of reducing the dwell time of ozone in the tower and improving the ozone utilization rate.

Aeration of Liquid‐Liquid Systems Using Various Agitators in a Mixer Equipped with a Membrane Diffuser

Abstract: Efficiency of the aeration of liquid mixtures is essential in many biochemical and chemical processes. In this work the analysis of power requirement needed to obtain three phase gas-liquid-liquid systems containing air, mineral oil and water, as modelling mixture, is presented. The influence of using various kinds of agitators consisting of two stirrers on common shaft and different volume fractions of oil ranging from 0.111 to 0.429 were investigated experimentally. The studies were performed for three configurations of stirrers consisting of either Smith disc, Rushton or flat blade turbines.

Membrane aeration bacteria-algae biological membrane system and application thereof

Abstract: The invention relates to a membrane aeration bacteria-algae biological membrane system and application thereof. The system comprises a reactor, an aeration diffuser arranged in the reactor, an aeration membrane fixed on the aeration diffuser and a sewage circulating unit arranged on the reactor, wherein a water inlet pipe is arranged at the bottom of the reactor, a water outlet pipe is arranged at the top of the reactor, an air inlet pipe is arranged at the bottom of the aeration diffuser, an air outlet pipe is arranged at the top of the aeration diffuser, and microorganisms and microalgae grow on the aeration membrane. The system is used for synchronously removing the organic matter, nitrogen and phosphorus in sewage. The membrane aeration bacteria-algae biological membrane system is simple and compact in overall structure, stable in structure, good in adjusting flexibility, capable of synchronously and efficiently removing the organic pollutants, nitrogen and phosphorus in sewage in the sewage, economical and practical, and promising in application prospect.

Aroma diffuser with direct diffusion of essential oil and diffusing method thereof

Abstract: The present invention relates to an aroma diffuser with direct diffusion of essential oil, and an aroma diffusing method. The aroma diffuser comprises a base, a housing mounted on the base and an electric control element disposed on the housing. An essential oil bottle and a gasification element are also disposed on the housing, a pump element is disposed inside the housing and the open end of the essential oil bottle is connected to the lower end of the gasification element. The pump element is connected to the gasification element and the electric control element respectively and communicates with the gasification element. The gasified essential oil gas may be diffused to ambient air directly, rather than through the housing, the diffusion is fast, and the directly diffused essential oil does not need the dilution of water, greatly raising the efficiency of aromatherapy and meeting people's use requirements.

Press-fit bearing locking system, apparatus and method

Abstract: A press-fit bearing locking system, apparatus and method are described. A press-fit bearing locking system includes a diffuser having a diffuser groove on an inner diameter (ID), a bushing comprising an outer diameter (OD) press-fit into the grooved ID of the diffuser, the OD of the bushing having a bushing groove tracing a path of the diffuser groove, and a high thermal expansion material (HTEM) key seated within the bushing groove. A press-fit bearing locking method includes seating a HTEM key inside a groove on an OD of a bushing, press-fitting the bushing with HTEM key into a diffuser such that the bushing groove is opposite a groove on an ID of the diffuser, operating an electric submersible pump assembly including the diffuser during a temperature rise, and allowing the HTEM key to expand into the diffuser groove during the temperature rise to lock the bushing against the diffuser.

Numerical simulation methodologies for design and development of Diffuser-Augmented Wind Turbines – analysis and comparison

Abstract: Abstract Different numerical computation methods used to develop a methodology for fast, efficient, reliable design and comparison of Diffuser-Augmented Wind Turbine (DAWT) geometries are presented. The demand for such methods is evident, following the multitude of geometrical parameters that influence the flow character through ducted turbines. The results of the Actuator Disk Model (ADM) simulations will be confronted with a simulation method of higher order of accuracy, i.e. the 3D Fully-resolved Rotor Model (FRM) in the rotor design point. Both will be checked for consistency with the experimental results measured in the wind tunnel at the Institute of Turbo-machinery (IMP), Lodz University of Technology (TUL). An attempt to find an efficient method (with a compromise between accuracy and design time) for the flow analysis pertinent to the DAWT is a novel approach presented in this paper.

Fan, diffuser, and vacuum cleaner having the same

Abstract: A fan (100) of a vacuum cleaner (300) includes a motor (20), an impeller (30), and a diffuser (40). The diffuser (40) includes a bottom plate (42) and guide vanes (44) disposed on the bottom plate (42). The guide vanes (44) are evenly spaced and arranged along a circumferential direction of the bottom plate (42). Each guide vane (44) extends obliquely from an inner edge to an outer edge of the bottom plate (42). An outer end of each guide vane (44) extends beyond the outer edge of the bottom plate (42). Each guide vane (44) is deflected an angle (θ) of 30 to 70 degrees with respect to a tangential direction of the bottom plate (42) at the inner end of the guide vane (44). The outer end of each guide vane (44) is deflected an angle (γ) of 35 to 120 degrees along a circumferential direction with respect to the inner end of the guide vane (44).

Automated Diffuser Shape Optimization based on CFD Simulations and Surrogate Modeling

Abstract: An approach for the optimization of laminar flow in diffusers is presented. The goal in our optimization process is to maximize diffuser performance and, in this way, pressure recovery by optimizing the geometry. Our methodology is the optimization through wall contouring of a given two-dimensional diffuser length ratio. The developed algorithm uses the CFD software: Fluent for the hydrodynamic analysis and employs surrogate modeling and an expected improvement approach to optimization. The non-uniform rational basic splines (NURBS) are used to represent the shape of diffuser wall with three to nine design variables, respectively. The framework is assisted by the construction of Kriging model, for the management of the problem. The CFD software and the Kriging model have been combined for a fully automated operation using some special control commands on the MATLAB platform. In order to seek a balance between local and global search, an adaptive sample criterion is employed. The optimal design exhibits a reasonable performance improvement compared with the reference design.

Contact tip rotary lock of a welding torch

Abstract: A welding torch system includes a diffuser assembly that includes a locking mechanism to receive a contact tip. Additionally, the welding torch system includes the contact tip, which includes locking elements configured to interact with the locking mechanism of the diffuser assembly to secure the contact tip within the diffuser assembly. Further, the contact tip is rotated within the diffuser assembly to securely align the locking elements with the locking mechanism.

Diffuser and related methods

Abstract: A liquid diffuser includes a base, a liquid reservoir, a spout for resting on the reservoir and having an upper opening, a fan, a polymeric gasket encircling the liquid reservoir, and a cover. The gasket includes a flange extending over a portion of an upper surface of the base that extends laterally beyond the liquid reservoir. The cover is sized and configured to be positioned over and around the liquid reservoir and the spout, and to rest upon the flange of the gasket. Methods of assembling such a liquid diffuser include resting the spout upon the liquid reservoir, and resting the spout upon the flange of the gasket over the base. Method of using such a liquid diffuser include powering a transducer for generating atomized droplets of the liquid, and supplying power to the fan to carry the atomized droplets of the liquid out from the diffuser with forced airflow.

Jet pump manufactured using additive and subtractive machining techniques

Abstract: A jet pump is manufactured using additive and subtractive techniques. A tubular body and a diffuser formed therein form a monolithic structure. The tapered diffuser is continuously curved from a throat end to a discharge end. A cross-sectional area at the discharge end is optimized without compromising a cross-sectional area of a production conduit defined in an annular space between the body and the diffuser. The body can be shaped to include radially extending localized or circumferential protrusions to maximize fluid conduits within the pump. A one-way valve is formed within the production conduit using the additive and subtractive techniques and is integrated in the monolithic structure.