This page has only limited features, please log in for full access.

Unclaimed
Ender Demirel
Associate Professor, Dept. of Civil Engineering, Eskisehir Osmangazi Univ., Eskisehir 26480, Turkey (corresponding author). ORCID:

Honors and Awards

The user has no records in this section


Career Timeline

The user has no records in this section.


Short Biography

The user biography is not available.
Following
Followers
Co Authors
The list of users this user is following is empty.
Following: 0 users

Feed

Journal article
Published: 01 July 2020 in Journal of Environmental Engineering
Reads 0
Downloads 0

In water treatment plants, the design of contact tanks is of critical importance for effective disinfection of potable water. The most important design problem in these flow-through systems is the formation of recirculation and flow jet zones, which reduce mixing efficiency of the contact system. To this end, in this study, a porous baffle design is proposed as an alternative to the slot baffle design, which may provide an alternative solution to these problems. Experimental and numerical studies were conducted on a 1:10-scale laboratory model of a prototype water treatment contact tank located in the province of Eskisehir in Turkey. To understand the effectiveness of the proposed porous baffle design, before the use of alternative porous baffle designs, heterogeneous soil-gravel mixtures with specified porosities were prepared and placed inside the baffles such that the porosity of the baffle could alternatively be changed in the flow direction. The purpose here is to investigate the efficiencies of several baffle configurations without using elaborate solid baffle structures that will mimic the performance of the porous baffle. The porous designs were thoroughly investigated, relying on the efficiency indexes obtained from dye tracer experiments. Experimental studies conducted for different porosity distributions indicate that the baffle porosity should increase in the flow direction along the chamber length so that the flow jet entering to the chamber with high momentum should be allowed to pass to the neighboring chamber relatively higher than the flow jet emerging from the chamber. This important observation led to the design of the porous baffle with variable porosity in the flow direction for a controllable fluid transfer between neighboring chambers. The proposed design successfully improves the hydraulic efficiency from poor to average based on the baffling factor measure, and the Morrill (Mo) index approaches 2, which is recommended by regulations. To further ascertain the contribution of the proposed baffle design, a computational fluid dynamics (CFD) model was developed for the simulation of turbulent flow through the porous baffle, and it was validated by the experimental studies conducted in this study. The simulated mean velocity profiles and tracer results were in good agreement with the experimental results. Visualization of internal structure of the flow through the tank and the baffles revealed that the momentum of the entering flow jet to the chamber could effectively turn dead zones into active mixing zones in the neighboring chamber. The authors emphasize that in the final design, porous baffle solid structures will be used that will mimic the pore structure characteristics of the design alternatives determined in this study instead of the use of the soil-gravel mixtures in this experimental study.

ACS Style

M. Anil Kizilaslan; Nazhmiddin Nasyrlayev; A. Tolga Kurumus; Hasan Savas; Ender Demirel; Mustafa M. Aral. Experimental and Numerical Evaluation of a Porous Baffle Design for Contact Tanks. Journal of Environmental Engineering 2020, 146, 04020063 .

AMA Style

M. Anil Kizilaslan, Nazhmiddin Nasyrlayev, A. Tolga Kurumus, Hasan Savas, Ender Demirel, Mustafa M. Aral. Experimental and Numerical Evaluation of a Porous Baffle Design for Contact Tanks. Journal of Environmental Engineering. 2020; 146 (7):04020063.

Chicago/Turabian Style

M. Anil Kizilaslan; Nazhmiddin Nasyrlayev; A. Tolga Kurumus; Hasan Savas; Ender Demirel; Mustafa M. Aral. 2020. "Experimental and Numerical Evaluation of a Porous Baffle Design for Contact Tanks." Journal of Environmental Engineering 146, no. 7: 04020063.

Conference paper
Published: 24 April 2020 in E3S Web of Conferences
Reads 0
Downloads 0

Conventional designs of chlorine contact tanks in potable water treatment plants are insufficient in terms of disinfection efficiency due to low hydraulic and mixing efficiencies. Strong interaction of the turbulent flow with the solid baffles may adversely affect hydraulic, mixing and disinfection performance of the contact system. Recirculating and jet zones created in the tank may require high chlorine dosages to yield adequate disinfection levels, which can result in the formations of high disinfection by-products (DBPs) in the treated water. The use of treated water by the consumers with high chlorine dosages and DBPs may lead to environmental and health problems in the long-term. Disinfection efficiency of the tank can be increased by the modification of the baffles and required disinfection levels can be achieved using lower chlorine dosages. In this study, performance of a patented baffle design is evaluated by means of numerical simulations on a full-scale contact tank. Self-decomposition of the chlorine, pathogen inactivation and formation of Trihalomethane (TTHM) by-product are simulated using a second-order numerical model. Numerical results show that the new baffle design yields 3-log inactivation by using 40% less chlorine concentration than the conventional design and the amount of DBP can be decreased by 43%.

ACS Style

Mehmet Anil Kizilaslan; Ender Demirel; Mustafa M. Aral. Pathogen inactivation and by-product formation in a full-scale contact tank. E3S Web of Conferences 2020, 167, 01011 .

AMA Style

Mehmet Anil Kizilaslan, Ender Demirel, Mustafa M. Aral. Pathogen inactivation and by-product formation in a full-scale contact tank. E3S Web of Conferences. 2020; 167 ():01011.

Chicago/Turabian Style

Mehmet Anil Kizilaslan; Ender Demirel; Mustafa M. Aral. 2020. "Pathogen inactivation and by-product formation in a full-scale contact tank." E3S Web of Conferences 167, no. : 01011.

Journal article
Published: 02 April 2020 in Water
Reads 0
Downloads 0

In this study, a perforated baffle design is proposed to improve mixing in contact tanks. Turbulent flow through the perforated baffle is studied at the perforation hole scale. The contribution of jets emerging from the perforations to the mixing process is evaluated in terms of standard mixing indexes for various perforation parameters, such as the solidity ratio and hole diameter. Based on numerical simulation results, the two sets of perforated baffles that yielded the highest performance were manufactured from polycarbonate and tracer studies were conducted on a laboratory model. Comparison of numerical and experimental results demonstrates that the numerical model developed is reliable in simulating the flow through the perforated baffles and the associated mixing level in the contact tank. Numerical simulations indicate that the jet flow structure through the perforated baffle penetrates to the recirculation zones in the neighboring chambers and turns the dead zones into active mixing zones. Furthermore, large scale turbulent eddies shed by the perforations contribute to the mixing process in the chambers of the tank. With the use of the perforated baffle design, it is shown that the hydraulic efficiency of the tank can be improved from average to superior according to the baffling factor, and the associated mixing in the proposed design can be improved by 31% according to the Morrill index.

ACS Style

Nazhmiddin Nasyrlayev; M. Anil Kizilaslan; A. Tolga Kurumus; Ender Demirel; Mustafa M. Aral. A Perforated Baffle Design to Improve Mixing in Contact Tanks. Water 2020, 12, 1022 .

AMA Style

Nazhmiddin Nasyrlayev, M. Anil Kizilaslan, A. Tolga Kurumus, Ender Demirel, Mustafa M. Aral. A Perforated Baffle Design to Improve Mixing in Contact Tanks. Water. 2020; 12 (4):1022.

Chicago/Turabian Style

Nazhmiddin Nasyrlayev; M. Anil Kizilaslan; A. Tolga Kurumus; Ender Demirel; Mustafa M. Aral. 2020. "A Perforated Baffle Design to Improve Mixing in Contact Tanks." Water 12, no. 4: 1022.

Journal article
Published: 09 March 2020 in Water
Reads 0
Downloads 0

Interaction of recirculating and mean flow downstream of a submerged gate may form significant vortex structures, which may affect the stability of the gate. Although these flow structures that appear in submerged hydraulic jumps received considerable attention in the literature, relatively less work was devoted to the analysis and suppression of the vortex structures downstream of a submerged gate. In this work, internal flow structure and vortex dynamics around a submerged gate were investigated through laboratory tests and large-eddy simulation (LES) using computational fluid dynamics (CFD). It is shown that numerical results obtained for mean velocity field are in good agreement with the experimental measurements. A helical vortex pair connected with a horseshoe vortex system was identified within the roller region using high-resolution numerical simulations. Damping performance of different types of anti-vortex elements placed on the downstream face of the gate are evaluated based on numerical studies. It is shown that the horizontal porous baffle mounted at an elevation below the free surface reduced the vortex magnitudes in the roller region by 26.8%. With the implementation of the proposed vortex breaker, lift forces acting on the gate lip were reduced by 9.4% and drag forces acting on the downstream face of the gate were reduced by 8.6%. Finally, in this study, we assess the performance of the vortex breaker under different flow conditions.

ACS Style

Ender Demirel; Mustafa M. Aral. A Design for Vortex Suppression Downstream of a Submerged Gate. Water 2020, 12, 750 .

AMA Style

Ender Demirel, Mustafa M. Aral. A Design for Vortex Suppression Downstream of a Submerged Gate. Water. 2020; 12 (3):750.

Chicago/Turabian Style

Ender Demirel; Mustafa M. Aral. 2020. "A Design for Vortex Suppression Downstream of a Submerged Gate." Water 12, no. 3: 750.

Journal article
Published: 21 August 2019 in Processes
Reads 0
Downloads 0

The mixing and disinfection performance of a full-scale chlorine contact tank (CCT) is thoroughly investigated by means of numerical simulations for seasonal water supply variations in the water treatment plant (WTP) of Eskisehir in Turkey. Velocity measurements and tracer studies are carried out on a 1:10 scale laboratory model of the CCT to validate the numerical model. A good agreement between numerical and experimental results shows that the numerical model developed can be reliably used for the simulation of turbulent flow and solute transport in the full-scale CCT. Tracer studies indicate that the hydraulic performance of the CCT is classified as “average” according to the baffling factor, while the Morrill, Aral-Demirel (AD), and dispersion indexes indicate low mixing due to the recirculating and short-circuiting effects inside the chambers of the CCT. With respect to the first order modeling of chlorine decay and pathogen inactivation, chlorine concentrations are found to be significantly distinct for seasonal variations in water supply to maintain 3-log inactivation of Giardia cysts. A recently developed and patented slot-baffle design (SBD) is then applied to the full-scale CCT. It is found that the hydraulic efficiency of the CCT is improved to “high” and the Morrill index approaches 2, which identifies the system as a perfect mixing tank. Using the SBD, the chlorine demand has been successfully decreased by 19% while providing equivalent inactivation level. The novel SBD design also reduces energy loses in the turbulent flow through the tank and increases the energy efficiency of the CCT by 62%, which is significant for energy considerations in modern cities.

ACS Style

M. Anil Kizilaslan; Ender Demirel; Mustafa Aral; Aral. Efficiency Enhancement of Chlorine Contact Tanks in Water Treatment Plants: A Full-Scale Application. Processes 2019, 7, 551 .

AMA Style

M. Anil Kizilaslan, Ender Demirel, Mustafa Aral, Aral. Efficiency Enhancement of Chlorine Contact Tanks in Water Treatment Plants: A Full-Scale Application. Processes. 2019; 7 (9):551.

Chicago/Turabian Style

M. Anil Kizilaslan; Ender Demirel; Mustafa Aral; Aral. 2019. "Efficiency Enhancement of Chlorine Contact Tanks in Water Treatment Plants: A Full-Scale Application." Processes 7, no. 9: 551.

Journal article
Published: 02 November 2018 in Water
Reads 0
Downloads 0

A slot-baffle design used in water treatment tanks previously developed by the authors is used to suppress sloshing effects in an accelerated tank. This new application is another example of the versatility of the slot-baffle design in inducing turbulence in fluid flow systems, which has numerous uses in engineering applications. Large amplitude surface waves in a harmonically excited tank are simulated using a second-order accurate numerical model in OpenFOAM. The verification of the numerical model is performed by comparing the numerical results with existing laboratory measurements, which show a favorable agreement. Various slot configurations are studied in order to evaluate the damping performance during the external excitation of the tank. It is shown that the present design shows an effective dissipation performance in a broad range of oscillation frequencies, while 88% of the internal kinetic energy of the liquid is dissipated over thirty oscillation periods for the resonance case.

ACS Style

Ender Demirel; Mustafa M. Aral. Liquid Sloshing Damping in an Accelerated Tank Using a Novel Slot-Baffle Design. Water 2018, 10, 1565 .

AMA Style

Ender Demirel, Mustafa M. Aral. Liquid Sloshing Damping in an Accelerated Tank Using a Novel Slot-Baffle Design. Water. 2018; 10 (11):1565.

Chicago/Turabian Style

Ender Demirel; Mustafa M. Aral. 2018. "Liquid Sloshing Damping in an Accelerated Tank Using a Novel Slot-Baffle Design." Water 10, no. 11: 1565.

Journal article
Published: 01 September 2018 in Journal of Environmental Engineering
Reads 0
Downloads 0

Hydraulic and mixing efficiencies of contact tanks are evaluated using several indexes that are used in the literature. These indexes emphasize different aspects of flow and mixing processes in the mixing tank at different scales. Uniformity of the evaluations obtained from these indexes is necessary for unified characterization of the overall performance of contact tanks, which is very difficult to achieve. In this study, several contact tanks with different baffling configurations were studied using computational fluid dynamics (CFD) analysis in which three-dimensional hydrodynamic analysis of flow and transport of a conservative tracer within the flow field were studied. The performance data developed were extended by including the outcome of some of the earlier studies that are reported in the literature. The most common indexes that are used in the literature were used to evaluate the performance of these cases. The results indicate that the performance evaluation obtained for these cases was not consistent for all indexes. An analysis was performed to identify the suitability of the performance indexes for a specific performance parameter. Performance of the newly introduced AD index, which yields more consistent evaluations for both short-circuiting and dispersion evaluation in the contact tank, was compared with the performance of the Morrill index. A dimensionless energy-efficiency index was also proposed for the evaluation of the efficiency of the flow-through system in the tank.

ACS Style

Ender Demirel; Mustafa M. Aral. Performance of Efficiency Indexes for Contact Tanks. Journal of Environmental Engineering 2018, 144, 04018076 .

AMA Style

Ender Demirel, Mustafa M. Aral. Performance of Efficiency Indexes for Contact Tanks. Journal of Environmental Engineering. 2018; 144 (9):04018076.

Chicago/Turabian Style

Ender Demirel; Mustafa M. Aral. 2018. "Performance of Efficiency Indexes for Contact Tanks." Journal of Environmental Engineering 144, no. 9: 04018076.

Journal article
Published: 15 August 2018 in Water
Reads 0
Downloads 0

Three-dimensional numerical simulations are performed to evaluate the effect of porous baffles on the efficiency of water treatment contact tanks. A second-order accurate numerical model is employed for the solutions of unsteady flow and tracer transport through the porous baffles. The flow through the porous medium is characterized while using the Darcy-Forchheimer relationship. Large Eddy Simulation (LES) model is used to simulate the instantaneous mixing of the tracer in the chambers of the contact tank. Three different porosities are considered to evaluate the effect of porosity on the hydraulic and mixing efficiencies of the contact tank. Simulated time-averaged flow field shows that porous baffles that are placed at the entrance of each chamber could successfully mitigate short-circuiting and yield plug-flow conditions through the system for low porosities. Flow in the contact tank becomes laminar as the flow velocities decrease due to viscous effects and inertial resistance in the porous zone. For this case, the tracer is transported with bulk flow through the system and leaves the contact tank with a high peak seen in the Residence Time Distribution (RTD) plot. Porous layer increases the hydraulic efficiency of the conventional design from “poor” to “good” according to the baffling factor and increases the overall efficiency from “compromising” to “good” according to the AD index. Comparison of the performance of the porous layer with the previously developed slot-baffle design shows that the slot-baffle design increases the efficiency of the tank with increasing dispersion effects, whereas the porous design increases hydraulic efficiency and reduces the dispersion effects. While the porous design reduces energy efficiency by 33% due to a drastic increase in drag in the flow through porous zone, the slot-baffle design increases the energy efficiency of the conventional design by 67%.

ACS Style

M. Anil Kizilaslan; Ender Demirel; Mustafa M. Aral. Effect of Porous Baffles on the Energy Performance of Contact Tanks in Water Treatment. Water 2018, 10, 1084 .

AMA Style

M. Anil Kizilaslan, Ender Demirel, Mustafa M. Aral. Effect of Porous Baffles on the Energy Performance of Contact Tanks in Water Treatment. Water. 2018; 10 (8):1084.

Chicago/Turabian Style

M. Anil Kizilaslan; Ender Demirel; Mustafa M. Aral. 2018. "Effect of Porous Baffles on the Energy Performance of Contact Tanks in Water Treatment." Water 10, no. 8: 1084.

Journal article
Published: 01 March 2018 in Teknik Dergi
Reads 0
Downloads 0

Bu çalışmada bir temas tankının içindeki türbülanslı akış ile arıtıcı konsantrasyonunun hareketinin üç boyutlu sayısal benzetimi ikinci mertebeden yakınsak bir hesaplama modeli kullanılarak gerçekleştirilmiştir. Arıtıcının zamanla değişen akım ile karışımı Large Eddy Simulation (LES) türbülans yaklaşımı kullanılarak modellenmiştir. Temas tankının girişinden enjekte edilen arıtıcı konsantrasyonunun tankın çıkışındaki dağılımını gösteren Kalma Süresi Dağılımı (KSD) ve toplam KSD eğrileri kullanılarak temas tankının hidrolik ve karışım verimlerine ait endeksler belirlenmiştir. Tank içindeki şaşırtma perdeleri üzerinde yapılan değişiklik ile temas sisteminin verimi arttırılarak enerji sarfiyatlarının azaltılabileceği gösterilmiştir. Önerilen yeni perde tasarımı sayesinde temas tankının hidrolik verimi %44, karışım verimi ise %42 oranında arttırılmış, suyun iletilmesi için gereken enerji sarfiyatı ise %43 oranında azaltılmıştır.

ACS Style

Doç.Dr. Ender Demirel; Dr. Mustafa Mehmet Aral. An Efficient Contact Tank Design for Potable Water Treatment. Teknik Dergi 2018, 29, 1 .

AMA Style

Doç.Dr. Ender Demirel, Dr. Mustafa Mehmet Aral. An Efficient Contact Tank Design for Potable Water Treatment. Teknik Dergi. 2018; 29 (2):1.

Chicago/Turabian Style

Doç.Dr. Ender Demirel; Dr. Mustafa Mehmet Aral. 2018. "An Efficient Contact Tank Design for Potable Water Treatment." Teknik Dergi 29, no. 2: 1.

Journal article
Published: 01 September 2017 in Journal of Environmental Engineering
Reads 0
Downloads 0
ACS Style

Mustafa Aral; Ender Demirel. Novel Slot-Baffle Design to Improve Mixing Efficiency and Reduce Cost of Disinfection in Drinking Water Treatment. Journal of Environmental Engineering 2017, 143, 06017006 .

AMA Style

Mustafa Aral, Ender Demirel. Novel Slot-Baffle Design to Improve Mixing Efficiency and Reduce Cost of Disinfection in Drinking Water Treatment. Journal of Environmental Engineering. 2017; 143 (9):06017006.

Chicago/Turabian Style

Mustafa Aral; Ender Demirel. 2017. "Novel Slot-Baffle Design to Improve Mixing Efficiency and Reduce Cost of Disinfection in Drinking Water Treatment." Journal of Environmental Engineering 143, no. 9: 06017006.

Journal article
Published: 16 November 2016 in Water
Reads 0
Downloads 0

Mixing characteristics of multi-chambered contact tank are analyzed employing the validated three-dimensional numerical model developed in the companion paper. Based on the flow characterization, novel volumetric mixing efficiency definitions are proposed for the assessment of the hydrodynamic and chemical transport properties of the contact tank and its chambers. Residence time distribution functions are analyzed not only at the outlet of each chamber but also inside the chambers using the efficiency definitions for both Reynolds averaged Navier–Stokes (RANS) and large eddy simulation (LES) results. A novel tracer mixing index is defined to characterize short circuiting and mixing effects of the contact system. Comparisons of the results of these indexes for RANS and LES solutions indicate that mixing characteristics are stronger in LES due to the unsteady turbulent eddy mixing even though short circuiting effects are also more prominent in LES results. This result indicates that the mixing analysis based on the LES results simulates the mixing characteristics instantaneously, which is more realistic than that in RANS. Since LES analysis can capture turbulent eddy mixing better than RANS analysis, the interaction of recirculation and jet zones are captured more effectively in LES, which tends to predict higher turbulent mixing in the contact system. The analysis also shows that the mixing efficiency of each chamber of the contact tank is different, thus it is necessary to consider distinct chemical release and volumetric designs for each chamber in order to maximize the mixing efficiency of the overall process in a contact tank system.

ACS Style

Ender Demirel; Mustafa M. Aral. Unified Analysis of Multi-Chamber Contact Tanks and Mixing Efficiency Evaluation Based on Vorticity Field. Part II: Transport Analysis. Water 2016, 8, 537 .

AMA Style

Ender Demirel, Mustafa M. Aral. Unified Analysis of Multi-Chamber Contact Tanks and Mixing Efficiency Evaluation Based on Vorticity Field. Part II: Transport Analysis. Water. 2016; 8 (11):537.

Chicago/Turabian Style

Ender Demirel; Mustafa M. Aral. 2016. "Unified Analysis of Multi-Chamber Contact Tanks and Mixing Efficiency Evaluation Based on Vorticity Field. Part II: Transport Analysis." Water 8, no. 11: 537.

Journal article
Published: 02 November 2016 in Water
Reads 0
Downloads 0

Multi-chamber contact tanks have been extensively used in industry for water treatment to provide potable water to communities, which is essential for human health. To evaluate the efficiency of this treatment process, flow and tracer transport analysis have been used in the literature using Reynolds averaged Navier–Stokes (RANS) and large-eddy simulations (LES). The purpose of this study is two-fold. First a unifying analysis of the flow field is presented and similarities and differences in the numerical results that were reported in the literature are discussed. Second, the vorticity field is identified as the key parameter to use in separating the mean flow (jet zone) and the recirculating zones. Based on the concepts of vorticity gradient and flexion product, it is demonstrated that the separation of the recirculation zone and the jet zone, fluid-fluid flow separation, is possible. The separation of the recirculation zones and vortex core lines are characterized using the definition of the Lamb vector. The separated regions are used to characterize the mixing efficiency in the chambers of the contact tank. This analysis indicates that the recirculation zone and jet zone formation are three-dimensional and require simulations over a long period of time to reach stability. It is recognized that the characteristics of the jet zones and the recirculation zones are distinct for each chamber and they follow a particular pattern and symmetry between the alternating chambers. Hydraulic efficiency coefficients calculated for each chamber show that the chambers having an inlet adjacent to the free surface may be designed to have larger volumes than the chambers having wall bounded inlets to improve the efficiency of the contact tank. This is a simple design alternative that would increase the efficiency of the system. Other observations made through the chamber analysis are also informative in redefining the characteristics of the efficiency of the contact tank system.

ACS Style

Ender Demirel; Mustafa Aral. Unified Analysis of Multi-Chamber Contact Tanks and Mixing Efficiency Based on Vorticity Field. Part I: Hydrodynamic Analysis. Water 2016, 8, 495 .

AMA Style

Ender Demirel, Mustafa Aral. Unified Analysis of Multi-Chamber Contact Tanks and Mixing Efficiency Based on Vorticity Field. Part I: Hydrodynamic Analysis. Water. 2016; 8 (11):495.

Chicago/Turabian Style

Ender Demirel; Mustafa Aral. 2016. "Unified Analysis of Multi-Chamber Contact Tanks and Mixing Efficiency Based on Vorticity Field. Part I: Hydrodynamic Analysis." Water 8, no. 11: 495.

Journal article
Published: 01 June 2016 in Journal of Engineering Mechanics
Reads 0
Downloads 0

A previously developed computational model is used for wave run-up analysis in a generic two-dimensional reservoir subjected to major earthquake acceleration records. The model is based on numerical solution of the Navier-Stokes equations and pressure equation considering compressibility effects. An existing model has been revised by the volume of fluid (VOF) method with piecewise linear interface calculation (PLIC) to be able to compute violent wave motion in the reservoir and to predict the maximum wave run-up on the dam crest attributable to ground oscillations during an earthquake. The numerical method and the computer code are validated by comparing the free-surface waves with the data available in the literature. The surface wave run-up on a vertical dam is simulated for different reservoir depths using major earthquake acceleration records. Simulations show that the maximum wave height on a dam body depends on the maximum positive ground velocity. On the basis of dimensional analysis, simulation results are presented in a simple dimensionless expression that is proposed for the prediction of the maximum wave run-up on a dam face subjected to earthquake excitation. The proposed relationship can be used for estimation of safety freeboard of dams against earthquake-generated surface waves.

ACS Style

Ender Demirel; Ismail Aydin. Numerical Simulation and Formulation of Wave Run-Up on Dam Face due to Ground Oscillations Using Major Earthquake Acceleration Records. Journal of Engineering Mechanics 2016, 142, 06016001 .

AMA Style

Ender Demirel, Ismail Aydin. Numerical Simulation and Formulation of Wave Run-Up on Dam Face due to Ground Oscillations Using Major Earthquake Acceleration Records. Journal of Engineering Mechanics. 2016; 142 (6):06016001.

Chicago/Turabian Style

Ender Demirel; Ismail Aydin. 2016. "Numerical Simulation and Formulation of Wave Run-Up on Dam Face due to Ground Oscillations Using Major Earthquake Acceleration Records." Journal of Engineering Mechanics 142, no. 6: 06016001.

Journal article
Published: 01 June 2015 in Soil Dynamics and Earthquake Engineering
Reads 0
Downloads 0
ACS Style

Ender Demirel. Numerical simulation of earthquake excited dam-reservoirs with irregular geometries using an immersed boundary method. Soil Dynamics and Earthquake Engineering 2015, 73, 80 -90.

AMA Style

Ender Demirel. Numerical simulation of earthquake excited dam-reservoirs with irregular geometries using an immersed boundary method. Soil Dynamics and Earthquake Engineering. 2015; 73 ():80-90.

Chicago/Turabian Style

Ender Demirel. 2015. "Numerical simulation of earthquake excited dam-reservoirs with irregular geometries using an immersed boundary method." Soil Dynamics and Earthquake Engineering 73, no. : 80-90.

Journal article
Published: 06 April 2015 in Water and Environment Journal
Reads 0
Downloads 0

In this study, turbulent flow downstream of the submerged sluice gate was investigated experimentally and numerically. Experimental studies were conducted in a laboratory flume to measure the flow velocities and turbulence characteristics. Three‐dimensional computational fluid dynamics (CFD) simulation was performed to investigate the flow structure downstream of the sluice gate. It is found that the flow downstream of the submerged sluice gate is highly three‐dimensional and unsteady in nature because of the interaction of mean flow and recirculation flow. The three‐dimensional simulation results indicate that the interacted flow triggers the formation of two corner vortices. Secondary velocities associated with the free surface vortices are found to be about 6% of the mean jet velocity at the inlet, which is significant for the river bank erosion. Vortex induced free surface fluctuations were also observed in the vicinity of the submerged gate.

ACS Style

Ender Demirel. Measured and simulated flow downstream of the submerged sluice gate. Water and Environment Journal 2015, 29, 446 -455.

AMA Style

Ender Demirel. Measured and simulated flow downstream of the submerged sluice gate. Water and Environment Journal. 2015; 29 (3):446-455.

Chicago/Turabian Style

Ender Demirel. 2015. "Measured and simulated flow downstream of the submerged sluice gate." Water and Environment Journal 29, no. 3: 446-455.

Journal article
Published: 01 February 2012 in Journal of Engineering Mechanics
Reads 0
Downloads 0

A computational model is developed to analyze the hydrodynamic behavior of dam reservoirs during earthquakes. The mathematical model is based on the solution of two-dimensional (2D) Navier-Stokes equations in a vertical, semi-infinite domain truncated by a far-end boundary condition. A depth integrated continuity equation is used to track the deforming free-surface and ensure global mass conservation. A combination of Sommerfeld nonreflecting boundary and dissipation zone methods is implemented at the far end of the reservoir to prevent any back-reflections of pressure and free-surface waves. Nondimensionalized equations are used to compare contributions of each type of force to the development of the hydrodynamic pressure field and to the maximum run-up of free-surface waves on the dam face. Sinusoidal ground accelerations are applied to an idealized dam-reservoir system to analyze the system response. It is observed that the acoustic wave equation solution gives satisfactory results for the pressure field unless the contributions from the free-surface waves become significant at low reservoir depths. The surface wave run-up on the dam face is found to depend on the ground velocity, oscillation period, and the water depth. On the basis of numerical experiments, an expression for the wave run-up to predict conditions of overtopping from probable earthquake characteristics is proposed.

ACS Style

Ismail Aydin; Ender Demirel. Hydrodynamic Modeling of Dam-Reservoir Response during Earthquakes. Journal of Engineering Mechanics 2012, 138, 164 -174.

AMA Style

Ismail Aydin, Ender Demirel. Hydrodynamic Modeling of Dam-Reservoir Response during Earthquakes. Journal of Engineering Mechanics. 2012; 138 (2):164-174.

Chicago/Turabian Style

Ismail Aydin; Ender Demirel. 2012. "Hydrodynamic Modeling of Dam-Reservoir Response during Earthquakes." Journal of Engineering Mechanics 138, no. 2: 164-174.

Journal article
Published: 01 January 2009 in International Journal for Numerical Methods in Fluids
Reads 0
Downloads 0
ACS Style

Ender Demirel; Ismail Aydin. Global volume conservation in unsteady free surface flows with energy absorbing far-end boundaries. International Journal for Numerical Methods in Fluids 2009, 64, 689 -708.

AMA Style

Ender Demirel, Ismail Aydin. Global volume conservation in unsteady free surface flows with energy absorbing far-end boundaries. International Journal for Numerical Methods in Fluids. 2009; 64 (6):689-708.

Chicago/Turabian Style

Ender Demirel; Ismail Aydin. 2009. "Global volume conservation in unsteady free surface flows with energy absorbing far-end boundaries." International Journal for Numerical Methods in Fluids 64, no. 6: 689-708.