scholarly journals Steady-State Hydraulic Analysis of High-Rise Building Wastewater Drainage Networks: Modelling Basis

Buildings ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 344
Author(s):  
Colin Stewart ◽  
Michael Gormley ◽  
Yunpeng Xue ◽  
David Kelly ◽  
David Campbell
Keyword(s):  
Steady State ◽  
Pressure Profile ◽  
Hydraulic Pressure ◽  
High Rise ◽  
Discharge Water ◽  
Air Supply ◽  
Pressure Profiles ◽  
Drainage Networks ◽  
Flow Components ◽  
Using Data

A model is presented which allows steady-state pressure profiles in high-rise wastewater drainage networks to be related to intake air flowrates and discharge water flowrates. This model is developed using data taken from academic literature, and is based on experimental observations which suggest that a vertical annular downflow develops over distance such that the pressure gradient in the wet stack may be expressed as the sum of junction components and developed flow components. The model is used to analyse a simplified ‘medium rise’ primary vented system of height 40 m, hosting two inflow junctions, crossvents and Air Admittance Valves (AAVs). The model illustrates how the air supply configuration affects the airflow rates within the stack and the vents, and how the configuration affects the steady-state hydraulic pressure profile. The model offers the possibility of an alternative approach to the design of high-rise wastewater drainage networks, compared to existing design codes. These codes generally do not explain the role that the air admitted into the network has upon its performance.

scholarly journals NUMERICAL AND HYDRAULIC EXPERIMENTS ON BORE PRESSURE DUE TO TSUNAMI

2018 ◽  
pp. 18
Author(s):  
Tatsuto Kimura ◽  
Masahiro Masuko ◽  
Naoki Fujii ◽  
Hideki Kaida ◽  
Naoto Kihara
Keyword(s):  
Steady State ◽  
Tsunami Wave ◽  
Three Dimensional ◽  
Tohoku Earthquake ◽  
Pressure Profile ◽  
Quasi Steady State ◽  
The 2011 Tohoku Earthquake ◽  
Wave Pressure ◽  
Pressure Profiles ◽  
State Regime

The 2011 Tohoku earthquake tsunami struck a wide area of the northeastern coast of Japan, and many coastal structures and buildings were damaged by the tsunami. Most of the buildings were damaged by the tsunami wave pressure. After the tsunami, characteristics of tsunami waive pressures have been investigated by many researcher, and are being clarified. As shown in previous studies, there are three regimes charactering the vertical pressure profiles. The first one is the impulsive pressure, which is observed just after the tsunami-bore impacted structures. In this regime, strong hydrodynamic pressures are generated by the fluid-solid impact process. After that, the bore pressure is observed, and both the hydrodynamic and hydrostatic pressures contribute the pressure profile. After that, the flow near the structures reaches a quasi-steady state, and the pressure profile becomes hydrostatic. Most of the evaluation equations of tsunami wave pressure proposed by the previous studies can be used against the impulsive pressures and the pressures in the quasi-steady-state regime. On the other hand, the characteristics and quantitative evaluations of the bore pressure remain immature. In this study, in order to clarify the characteristics of the bore pressure, experiments on the bore pressure are carried out, and furthermore, three-dimensional numerical simulations are also carried out.

Surface Roughness Effects in an EHL Line Contact

1992 ◽  
Vol 114 (3) ◽  
pp. 616-622 ◽  
Author(s):  
C. H. Venner ◽  
W. E. ten Napel
Keyword(s):  
Surface Roughness ◽  
Steady State ◽  
Film Thickness ◽  
Pressure Profile ◽  
Line Contact ◽  
Roughness Effects ◽  
Misleading Information ◽  
Roughness Profile ◽  
Pressure Profiles ◽  
Load Conditions

In this paper the influence of surface roughness on the pressure profile and film thickness in a steady state EHL line contact is investigated using input from an actually measured roughness profile in the calculations. Pressure profiles and film shapes for different load conditions are shown. The presented results strongly indicate that in the steady state situation considered here a significant deformation of the roughness profile occurs. As a result the often used λ parameter being the ratio of film thickness and standard deviation of the roughness (h/σ) with σ based on the undeformed roughness profile may give misleading information as far as the effect of the roughness on pressure and film shape is concerned.

Modeling and Optimization of Pressure Profile in Hydroforming of St12 Conic Part with RSM and Genetic Algorithm

2011 ◽  
Vol 473 ◽  
pp. 587-593
Author(s):  
Hamzeh Shahrajabian ◽  
Khalil Khalili ◽  
M. Soheil Khalili
Keyword(s):  
Genetic Algorithm ◽  
Finite Element ◽  
Element Model ◽  
Pressure Profile ◽  
Hydraulic Pressure ◽  
Response Surface Modeling ◽  
Optimum Pressure ◽  
Pressure Profiles ◽  
Hydroforming Process ◽  
The Finite Element Model

One of the most effective methods of manufacturing conical parts is the hydroforming process. The pressure profile during forming is the most important factor on wrinkling, thinning, and punch wall contact. This paper presents a methodology to determine the optimal profile of hydraulic pressure during hydroforming of conical parts. The objective is to minimize the variation of the thickness throughout the part. Initially, the finite element model is developed and verified. The part being modeled is then subjected to different pressure profiles to examine the effect of each profile on thinning. The Response Surface Modeling (RSM) along with Genetic Algorithm (GA) is employed to obtain the optimum pressure profile. The paper describes the methodology developed and reports the results obtained.

scholarly journals Propagation of radiosonde pressure sensor errors to ozonesonde measurements

2014 ◽  
Vol 7 (1) ◽  
pp. 65-79 ◽  
Author(s):  
R. M. Stauffer ◽  
G. A. Morris ◽  
A. M. Thompson ◽  
E. Joseph ◽  
G. J. R. Coetzee ◽  
...  
Keyword(s):  
Pressure Sensor ◽  
Atmospheric Pressure ◽  
Pressure Profile ◽  
Mixing Ratio ◽  
Concentration Cell ◽  
Pressure Profiles ◽  
Dependent Variables ◽  
Sensor Errors ◽  
Subsequent Addition ◽  
Total Column

Abstract. Several previous studies highlight pressure (or equivalently, pressure altitude) discrepancies between the radiosonde pressure sensor and that derived from a GPS flown with the radiosonde. The offsets vary during the ascent both in absolute and percent pressure differences. To investigate this problem further, a total of 731 radiosonde/ozonesonde launches from the Southern Hemisphere subtropics to northern mid-latitudes are considered, with launches between 2005 and 2013 from both longer term and campaign-based intensive stations. Five series of radiosondes from two manufacturers (International Met Systems: iMet, iMet-P, iMet-S, and Vaisala: RS80-15N and RS92-SGP) are analyzed to determine the magnitude of the pressure offset. Additionally, electrochemical concentration cell (ECC) ozonesondes from three manufacturers (Science Pump Corporation; SPC and ENSCI/Droplet Measurement Technologies; DMT) are analyzed to quantify the effects these offsets have on the calculation of ECC ozone (O3) mixing ratio profiles (O3MR) from the ozonesonde-measured partial pressure. Approximately half of all offsets are > ±0.6 hPa in the free troposphere, with nearly a third > ±1.0 hPa at 26 km, where the 1.0 hPa error represents ~ 5% of the total atmospheric pressure. Pressure offsets have negligible effects on O3MR below 20 km (96% of launches lie within ±5% O3MR error at 20 km). Ozone mixing ratio errors above 10 hPa (~ 30 km), can approach greater than ±10% (> 25% of launches that reach 30 km exceed this threshold). These errors cause disagreement between the integrated ozonesonde-only column O3 from the GPS and radiosonde pressure profile by an average of +6.5 DU. Comparisons of total column O3 between the GPS and radiosonde pressure profiles yield average differences of +1.1 DU when the O3 is integrated to burst with addition of the McPeters and Labow (2012) above-burst O3 column climatology. Total column differences are reduced to an average of −0.5 DU when the O3 profile is integrated to 10 hPa with subsequent addition of the O3 climatology above 10 hPa. The RS92 radiosondes are superior in performance compared to other radiosondes, with average 26 km errors of −0.12 hPa or +0.61% O3MR error. iMet-P radiosondes had average 26 km errors of −1.95 hPa or +8.75 % O3MR error. Based on our analysis, we suggest that ozonesondes always be coupled with a GPS-enabled radiosonde and that pressure-dependent variables, such as O3MR, be recalculated/reprocessed using the GPS-measured altitude, especially when 26 km pressure offsets exceed ±1.0 hPa/±5%.

Patterns and Reduced-order Reconstruction of Impinging Wiping Jet Pressure Profile Fluctuation Using Proper Orthogonal Decomposition

2021 ◽  
Author(s):  
Le Quang Phan ◽  
Andrew Johnstone ◽  
P. Buyung Kosasih ◽  
Wayne Renshaw
Keyword(s):  
Proper Orthogonal Decomposition ◽  
Jet Impingement ◽  
Pressure Profile ◽  
Orthogonal Decomposition ◽  
Maximum Pressure ◽  
Frequency Spectra ◽  
Reduced Order ◽  
Order Reconstruction ◽  
Pressure Profiles ◽  
Proper Orthogonal

Abstract Wiping jet impingement pressure is important in controlling the coating mass (thickness) and influencing the smoothness of the thin metallic coating produced in continuous galvanizing lines (CGLs). However, the fluctuation of the impingement pressure profile that directly impacts the coating smoothness has not been adequately understood. To study key features of the impingement pressure fluctuation, the instantaneous impingement pressure profiles obtained from Large Eddy Simulations were analyzed using Proper Orthogonal Decomposition (POD). Dominant fluctuation modes of pressure profiles can be differentiated from the energy contents of the modes corresponding to different jet types namely mixing, non-mixing, and transitional mixing jet. The dominant modes of mixing jets in the wiping region contain comparable strength of all modes (flapping, pulsing, and out-of-phase multi pulsing). Non-mixing jets do not show discernable fluctuation modes and transitional mixing jets show pulsing and flapping modes only. Additionally, instantaneous maximum pressure gradient and their location were determined from the reduced-order reconstruction of the pressure profiles. From the analysis, frequency spectra of the magnitude and location fluctuations of the maximum pressure gradients associated with each of the jet types can be clearly distinguished. This is a knowledge that may be helpful for CGL operators in the operation of wiping jets.

scholarly journals Mechanical Fault Detection on Electrical Machine: Thermal Analysis of Small Brushed DC Motor with Faulty Bearing

2018 ◽  
Vol 225 ◽  
pp. 05012
Author(s):  
Abbas A. Wahab ◽  
N. Fatimah Abdullah ◽  
M.A.H. Rasid
Keyword(s):  
Thermal Analysis ◽  
Steady State ◽  
Direct Current ◽  
Dc Motor ◽  
Temperature Data ◽  
Electrical Machine ◽  
Financial Loss ◽  
Data Logger ◽  
Steady State Temperature ◽  
Using Data

Direct current motors (DC motor) are used in the small electric devices commonly. DC motor are cheap and easy to install, thus their popularity. Despite the popularity, faults occur which make diagnosis and detection of faults very important. It avoids financial loss and unexpected shutdown operation causes by these faults. This paper presents an analysis of temperature profile of the much famous small Brushed DC motor with a faulty bearing. The temperature data of healthy DC motor and DC motor with faulty bearing were measured by thermocouple and recorded using data logger in real time until steady state temperature, under different load. The analysis on the steady state temperature allow to conclude that bearing fault can clearly be recognised through characteristics temperature difference with a healthy motor.

The Effects of Oil Supply Pressure at different Groove Position on Temperature and Pressure Profile in Journal Bearing

2013 ◽  
Vol 66 (3) ◽  
Author(s):  
Mohamad Ali Ahmad ◽  
Salmiah Kasolang ◽  
R. S. Dwyer-Joyce ◽  
Aidah Jumahat
Keyword(s):  
Journal Bearing ◽  
Pressure Profile ◽  
Diameter Ratio ◽  
Radial Load ◽  
Oil Supply ◽  
Supply Pressure ◽  
Pressure Profiles ◽  
Hydrodynamic Journal Bearing ◽  
Temperature And Pressure ◽  
Length To Diameter Ratio

The effects of oil supply pressure on the temperature and pressure at different groove locations on a hydrodynamic journal bearing were investigated. A journal with a diameter of 100 mm and a ½ length-to-diameter ratio was used. The supply pressure was set to 0.2, 0.5, and 0.7 MPa at seven different groove locations, namely, -45°, -30°, -15°, 0°, +15°, +30°, and +45°. Temperature and pressure profiles were measured at speed values of 300, 500, and 800 rpm with 10 kN radial load. The results show that the change in oil supply pressure simultaneously reduced the temperature and increased the pressure profile.

scholarly journals BLOOD PRESSURE PROFILES AMONG EAST BONGAS AND WEST BONGAS PEOPLE IN EFFORT AND SUPPORT FROM UNIVERSITAS PADJADJARAN AND THE REGENT OF MAJALENGKA REGENCY AND CHIEVES OF THE VILLAGES

2017 ◽  
Vol 9 (6) ◽  
pp. 215
Author(s):  
Diah Dhianawaty D. ◽  
Henhen Heryaman ◽  
Mas Rizky Anggun Adipurna Syamsunarno
Keyword(s):  
Blood Pressure ◽  
Age Groups ◽  
Simple Random Sampling ◽  
Pressure Profile ◽  
Joint National Committee ◽  
National Committee ◽  
Cross Sectional ◽  
Male And Female ◽  
The People ◽  
Pressure Profiles

Objective: To support the people in East Bongas and West Bongas villages to prevent and treatment the hypertension disease.Methods: This was a cross-sectional design while the subjects were taken by a simple random sampling. A total of 323 families were included, and blood pressure of the male and female subjects aged between 18 to 65 y was measured and had been given a question relating to their blood pressure.Results: The blood pressure profile was classified based on the seventh report of the Joint National Committee (JNC 7). The youngest male and female participants of pre-hypertension were 18 and 22 y, respectively. The normal blood pressure, pre-hypertension, hypertension stage-1, and hypertension stage-2 were 34.3%, 49.5%, 12.1%, and 4.1%, respectively. Prevalence of patients with hypertension based on the age groups 30-39, 40-49, 50-59, and 60-69 y were 6.8%, 15.6%, 33.9%, and 37.3%, respectively. Prevalence of patients with hypertension in male was 16.8%, the female was 15.7%, and the total of both were 16.2%. Prevalence based on gender showed that those who had information about hypertension in male was 46.8%, the female was 47.9%, and the total of both were 47.4%. Prevalence of hypertension patients increased, for a male was 8.9%, the female was 8.2%, and the total of both were 8.5% after the participants declared that they were not hypertension patients.Conclusion: In both villages occurred an increase of hypertension prevalence. Based on this information, the people in two villages should be given the appropriate knowledge and awareness regarding hypertension.

scholarly journals Variational analysis of landscape elevation and drainage networks

2020 ◽  
Vol 476 (2239) ◽  
pp. 20190775
Author(s):  
Milad Hooshyar ◽  
Shashank Anand ◽  
Amilcare Porporato
Keyword(s):  
Steady State ◽  
Variational Analysis ◽  
Variational Principles ◽  
Landscape Evolution ◽  
Essential Dynamics ◽  
Channel Networks ◽  
Soil Transport ◽  
Drainage Networks ◽  
Average Domain

Landscapes evolve towards surfaces with complex networks of channels and ridges in response to climatic and tectonic forcing. Here, we analyse variational principles giving rise to minimalist models of landscape evolution as a system of partial differential equations that capture the essential dynamics of sediment and water balances. Our results show that in the absence of diffusive soil transport the steady-state surface extremizes the average domain elevation. Depending on the exponent m of the specific drainage area in the erosion term, the critical surfaces are either minima (0 <  m  < 1) or maxima ( m  > 1), with m  = 1 corresponding to a saddle point. We establish a connection between landscape evolution models and optimal channel networks and elucidate the role of diffusion in the governing variational principles.

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