Risk Exposure during Showering and Water-Saving Showers

Eco-friendly showers aim to lower energy and water consumption by generating smaller water droplets than those produced by traditional systems. To evaluate the risk of users inhaling the contaminants associated with such water droplets—namely, chemical components or opportunistic bacterial pathogens such as Legionella—we modeled the behavior of water droplets aerosolized by water-atomization technology at a flow rate of 2.2 L/min and compared the results obtained using this model with those determined experimentally in a typical shower stall. Additionally, we monitored the number and mass of inhalable water droplets emitted by twelve showerheads—eight using water-atomization technology and four using continuous-flow technology—which have distinct characteristics in terms of water flow rate, water pressure, spray angle, and number of and diameter of nozzles. The water-atomizing showers tested not only had lower flow rates, but also larger spray angles, less nozzles, and larger nozzle diameters than those of the continuous-flow showerheads. We observed a difference in the behavior of inhalable water droplets between the two technologies, both unobstructed and with the presence of a mannequin. The evaporation of inhalable water droplets emitted by the water-atomization showers favored a homogenous distribution in the shower stall. In the presence of the mannequin, the number and mass of inhalable droplets increased for the continuous-flow showerheads and decreased for the water-atomization showerheads. The water-atomization showerheads emitted less inhalable water mass than the continuous-flow showerheads did per unit of time; however, they generally emitted a slightly higher number of inhalable droplets (1.6 times more), including those large enough to carry a bacterium each—only one model performed as well as the continuous-flow showerheads in this regard. Further experiments are needed to assess whether this slight increase in the number of inhalable water droplets increases the biological risk.

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Experimental Studies of Rotation Efficiency of Packing on Characteristics of Counter Flow Wet Cooling Tower

Volume 6B: Energy ◽

10.1115/imece2014-37108 ◽

2014 ◽

Author(s):

Khashayar Teimoori ◽

Ali M. Sadegh

Keyword(s):

Mass Flow ◽

Flow Rate ◽

Rotational Speed ◽

Water Mass ◽

Water Flow Rate ◽

Experimental Studies ◽

Counter Flow ◽

Flow Rates ◽

Mass Flow Rates ◽

Water Mass Flow Rate

Packing in cooling towers is commonly used in nuclear power plants and air conditioning systems. However their efficiency with respect to the inlet air flow rate and the temperature of the water has not been fully investigated. In this research, the efficiency of packing rotational speed with respect to the wet counter flow of a cooling tower is experimentally investigated. In our experimental studies, six elliptical wooden plates that are equally spaced are used as a packing tower. The packing area of 0.85 m2 is considered with the following rotor speed ranges: 0.5, 3.5, 10, 15 and 17 rpm. It is assumed that the water mass flow rate is proportional to the inlet air to the tower. Six mass flow rates starting from 0.2 to 2.8 kg/h and the inlet air and water temperatures of 27°C and 45°C, respectively, are considered. The results illustrate that for the range of 0 to 5 rpm of the packing rotational speed the cooling rate of water is increased 3% for the water flow rate of 2.8 kg/h, and 24% for the water flow rate of 0.4 kg/h. Additionally, as a result of the increased rotational speed from 5 to over 17 rpm the cooling rate at both maximum and minimum water mass flow rates are increased from 13.9 to 34.4 percent, respectively. Furthermore, the water outlet temperature is reduced from 8.6°C to 3.3°C in the least and the most mass flow rates leading to the increased speed from 5 to 17 rpm, respectively. The experimental relationship between the inlet air temperature and the rotational speed of the packing has been determined. Also, the inlet water temperature at the maximum flow rate has been decreased to 3.4 and at the least water mass flow rate it has been decreased to 29 percent for the range of rotational speed from 5 to over 17 rpm of the packing rotation. All the results are depicted in several curves to show the actual variations of the variables.

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Device Substantiation for Generating Artificial Rain Drops by Pneumohydraulic Liquid Spraying

Agricultural machinery and technologies ◽

10.22314/2073-7599-2021-15-2-53-60 ◽

2021 ◽

Vol 15 (2) ◽

pp. 53-60

Author(s):

V. P. Gorobey ◽

V. Y. Moskalevich ◽

Z. A. Godzhaev

Keyword(s):

Flow Rate ◽

Water Pressure ◽

Water Flow Rate ◽

Cell Diameter ◽

Technological Parameters ◽

Outlet Nozzle ◽

Annular Gap ◽

Rain Drops ◽

Artificial Rain ◽

Air Nozzle

The authors studied the pneumohydraulic device indicators for spraying liquids for irrigation, nutrition and protection of agricultural plants, taking into account the principles of water and energy conservation, based on preliminary gas saturation of sprayed water and the use of a cavitation effect in the design of the aerator unit during ejection and supply of air under pressure. (Research purpose) To determine the technological parameters of a pneumohydraulic device for spraying liquids to obtain controlled dispersive artificial rain and substantiate the choice of its optimal technical parameters depending on the operating modes. (Materials and methods) The authors used an algorithm for calculating parameters in EXCEL or WPS spreadsheet processor and mathematical expressions. (Results and discussion) The authors theoretically determined the minimum and maximum calculated parameters of the constructive solution geometry for spraying the liquid phase: water nozzle, air nozzle channel, mixing cell, middle annular gap, outlet nozzle. They changed indicators of operating water pressure – 0.20; 0.25; 0.30 and 0.35 megapascals; air – 0.25 and 0.30 megapascals, provided the water flow rate from 0.002 to 0.010 liter per second and air – from 0.0005 to 0.0090 kilogram per second. With an increase in the water flow rate within the specified limits and the ejection coefficient from 0.5 to 0.9, a linear increase in the average annular gap diameter from 2 to 15 millimetres was revealed, as well as a nonlinear dependence of the increase in the sprayer mixing cell diameter from 5 to 20 millimetres. The authors showed the possibility of reducing the mixing cell diameter if the water pressure was increased from 0.25 to 0.35 megapascal's and the air pressure was from 0.20 to 0.30 megapascals. They obtained the parameters values for the designed and experimental samples development, which turned out to be significantly less than when operating in the air ejection mode: the outlet nozzle and the middle annular gap – by 16 percent, the air nozzle – by 23, the diameter of the mixing cell – by 50 percent or more. (Conclusions) The authors obtained calculated data to optimize technological parameters and design solutions, which would speed up the manufacture of designed and model samples of the device and its experimental testing for the generation of dispersive artificial rain drops.

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Water Discharge Management Based on Open and Closed Cylinders in the Gravitation Water Vortex Power Plant

JEEE-U (Journal of Electrical and Electronic Engineering-UMSIDA) ◽

10.21070/jeeeu.v5i1.1008 ◽

2021 ◽

Vol 5 (1) ◽

pp. 22-36

Author(s):

Muhammad Hasan Basri ◽

Ainun Nasuki

Keyword(s):

Power Plant ◽

Water Flow ◽

Flow Rate ◽

Water Pressure ◽

Water Discharge ◽

Water Flow Rate ◽

Discharge Measurement ◽

Closed Basin ◽

Advantages And Disadvantages ◽

Discharge Management

A Gravitation Water Vortex Power Plant (GWVPP) tool has been made to determine how much water flow is needed to generate electricity. This research was conducted by changing the flow rate and water pressure to determine the effect on the performance of a vortex power plant, and in previous studies, no one has made changes to the discharge and water pressure. The type of basin position used in this study is an open basin position and a closed basin position. Based on the advantages and disadvantages of each type of blade used, a study was carried out using the type of turbine blade model L by changing the water flow rate and water pressure at a predetermined position to determine the effect of water discharge and pressure on the turbine rotational speed. From the results of testing the water discharge measurement in a closed basin which is carried out on the addition of each flow of water discharge at the angle of the faucet 0o to 90o with a volume (V) 98 L and time (t) 1.11 minutes to 2.5 minutes, it can be seen that the average discharge value (Q) the resulting 81.08 l / s. and from the results of testing the water discharge measurement in the open basin which is carried out to the addition of each flow of water discharge at the angle of the faucet 0o to 90o with a volume (V) 98 L and time (t) 1.28 minutes to 4.1 minutes it can be seen that the average discharge value (Q ) resulting in 65.21 l / s.

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Continuous-flow high temperature and pressure water sterilizer

Water Practice & Technology ◽

10.2166/wpt.2015.003 ◽

2015 ◽

Vol 10 (1) ◽

pp. 19-24

Author(s):

Adrian Ponce

Keyword(s):

High Temperature ◽

Flow Rate ◽

Continuous Flow ◽

Low Cost ◽

Water Flow Rate ◽

Geobacillus Stearothermophilus ◽

High Temperature And Pressure ◽

Point Of Use ◽

Pressure Water ◽

Temperature And Pressure

Water sterilization at sterility assurance levels exceeding 10−6 has been achieved with a novel high temperature and pressure sterilization system (HAPSS) capable of continuous-flow sterilization. The tested sterilizer produces >2,000 L/day and does not require filters, moving parts, or regular maintenance and can operate for multiple years with only water and standard voltage/amperage electricity. Sterility assurance levels were determined using Geobacillus stearothermophilus spores with inactivation experiments as a function of temperature and flow rate (i.e., duration/dosage at given temperature). Sterility of 1.0 × 104 CFU/mL G. stearothermophilus spore suspensions was achieved at the highest water flow rate of 1.4 L/min at 140 and 130 °C. The low cost and maintenance-free operation of HAPSS is envisioned to impact water sterilization needs of developing nations, hospitals, and commercial point of use applications.

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Impact assessment for water pressure and turbidity occurrence by changes in water flow rate of large consumer at water distribution networks

Journal of The Korean Society of Water and Wastewater ◽

10.11001/jksww.2014.28.3.277 ◽

2014 ◽

Vol 28 (3) ◽

pp. 277-286 ◽

Cited By ~ 1

Author(s):

Doo Yong Choi ◽

Ju-Hwan Kim ◽

Min-Ah Choi ◽

Do-Hwan Kim

Keyword(s):

Impact Assessment ◽

Water Flow ◽

Flow Rate ◽

Water Distribution ◽

Water Pressure ◽

Water Flow Rate ◽

Distribution Networks ◽

Water Distribution Networks

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Predicting Performance of a Condenser With Plugged Tubes

ASME 2005 Power Conference ◽

10.1115/pwr2005-50057 ◽

2005 ◽

Author(s):

Gene L. Minner ◽

Gerald Weber

Keyword(s):

Heat Transfer ◽

Heat Transfer Coefficient ◽

Transfer Coefficient ◽

Flow Rate ◽

Water Pressure ◽

Water Flow Rate ◽

Plant Performance ◽

Hydraulic Pressure ◽

Pressure Drops ◽

Circulating Water

The electric power generated in a steam-power plant depends on condenser pressure. Plant performance personnel are frequently called upon to predict effects on megawatts generated and plant heat rate as condenser circumstances vary. The flow rate of circulating water to the condenser is one of the factors that impact the results when doing such predictions. This paper utilizes the PEPSE modeling program to evaluate the effect on the condenser back-pressure and power generation of plugging condenser tubes. The circulating water flow rate is the focal point of this analysis because it influences the heat transfer coefficient inside of the tubes of the condenser. This inside-tube convection heat transfer coefficient is an important contributor to the calculated overall condensing heat transfer coefficient and the resulting condenser pressure. Calculation of the condenser’s shell side pressure is based on the Heat Exchange Institute’s (HEI) methods that are standard in the industry. In operation the circulating water’s flow rate occurs at the point where the head of the circulating water pump balances the hydraulic pressure drops in the circuit. Equations are presented to account for circulating water pressure drops, as foundation for calculations of the hydraulic balancing. The equation methodology is then applied to an actual condenser design.

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Enhancing the renewable energy payback period of a photovoltaic power generation system by water flow cooling

International Journal of Solar Thermal Vacuum Engineering ◽

10.37934/stve.3.1.7385 ◽

2021 ◽

Vol 3 (1) ◽

pp. 73-85

Author(s):

Ali Sohani ◽

Mohammad Hassan Shahverdian ◽

Hoseyn Sayyaadi ◽

Siamak Hoseinzadeh ◽

Saim Memon

Keyword(s):

Mass Flow Rate ◽

Water Flow ◽

Mass Flow ◽

Flow Rate ◽

Water Mass ◽

Water Flow Rate ◽

Payback Period ◽

Energy Payback ◽

Water Mass Flow Rate ◽

The Impact

A photovoltaic system which enjoys water flow cooling to enhance the performance is considered, and the impact of water flow rate variation on energy payback period is investigated. The investigation is done by developing a mathematical model to describe the heat transfer and fluid flow. A poly crytalline PV module with the nomical capacity of 150 W that is located in city Tehran, Iran, is chosen as the case study. The results show that by incresing water flow rate, EPBP declines first linearly, from the inlet water flow rate of 0 to 0.015 kg.s-1, and then, EPBP approaches a constant value. When there is no water flow cooling, EPBP is 8.88, while by applying the water flow rate of 0.015 kg.s-1, EPBP reaches 6.26 years. However, only 0.28 further years decreament in EPBP is observed when the inlet water mass flow rate becomes 0.015 kg.s-1. Consequently, an optimum limit for the inlet water mass flow rate could be defined, which is the point the linear trend turns into approaching a constant value. For this case, as indicated, this value is 0.015 kg.s-1.

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On the Influence of the Slot Orifice in Diesel Common Rail Nozzle

The Open Fuels & Energy Science Journal ◽

10.2174/1876973x01811010055 ◽

2018 ◽

Vol 11 (1) ◽

pp. 55-69 ◽

Cited By ~ 1

Author(s):

Giancarlo Chiatti ◽

Ornella Chiavola ◽

Fulvio Palmieri ◽

Roberto Pompei

Keyword(s):

Cross Section ◽

Flow Rate ◽

Experimental Analysis ◽

Common Rail ◽

Spray Angle ◽

The Novel ◽

Hydraulic Behavior ◽

Reference Information ◽

Light Duty ◽

Set Up

Background:The paper deals with a diesel common rail nozzle in which a novel orifice layout is implemented.Objective:Its influence on the nozzle mechanical-hydraulic behavior and on the spray shape transient development is experimentally investigated.Methods:In the research, a solenoid injector for light duty diesel engines is equipped with the novel nozzle prototype and tested. The prototype layout is described, pointing out the features of the nozzle orifices, in which a Slot cross-section is adopted; the investigation is accomplished extending the hydraulic tests and the spray visualizations to a reference nozzle with standard holes. The influence of the hole layout on the mechanical-hydraulic behavior of the nozzle is assessed by experimental analysis based on the rate of injection measurement, in comparison with the reference nozzle. Once the hydraulic behavior of the novel nozzle has been characterized in terms of mass flow rate, the slot influence on the spray shape is assessed analyzing the macroscopic features such as the penetration distance and the spray angle, in non evaporative conditions. The study is carried out under transient injection conditions, for different injection pressures, up to 1400 bar.Results:The results on spray characteristics also provide reference information to set up spray models suited to take the Slot orifice into account.

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Effect of Water Flow on Underwater Wet Welded A36 Steel

Metals ◽

10.3390/met11050682 ◽

2021 ◽

Vol 11 (5) ◽

pp. 682

Author(s):

Eko Surojo ◽

Aziz Harya Gumilang ◽

Triyono Triyono ◽

Aditya Rio Prabowo ◽

Eko Prasetya Budiana ◽

...

Keyword(s):

Mechanical Properties ◽

Water Flow ◽

Flow Rate ◽

Water Flow Rate ◽

Physical And Mechanical Properties ◽

Shielded Metal Arc Welding ◽

Effect Of Water ◽

Bending Effect ◽

Metal Arc Welding ◽

A36 Steel

Underwater wet welding (UWW) combined with the shielded metal arc welding (SMAW) method has proven to be an effective way of permanently joining metals that can be performed in water. This research was conducted to determine the effect of water flow rate on the physical and mechanical properties (tensile, hardness, toughness, and bending effect) of underwater welded bead on A36 steel plate. The control variables used were a welding speed of 4 mm/s, a current of 120 A, electrode E7018 with a diameter of 4 mm, and freshwater. The results show that variations in water flow affected defects, microstructure, and mechanical properties of underwater welds. These defects include spatter, porosity, and undercut, which occur in all underwater welding results. The presence of flow and an increased flow rate causes differences in the microstructure, increased porosity on the weld metal, and undercut on the UWW specimen. An increase in water flow rate causes the acicular ferrite microstructure to appear greater, and the heat-affected zone (HAZ) will form finer grains. The best mechanical properties are achieved by welding with the highest flow rate, with a tensile strength of 534.1 MPa, 3.6% elongation, a Vickers microhardness in the HAZ area of 424 HV, and an impact strength of 1.47 J/mm2.

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