Experimental study on flow over sinusoidal and semicircular labyrinth weirs

Zadeh, Milad Safarrazavi; Varaki, M Esmaeili; Biabani, Roya

doi:10.1080/09715010.2019.1644679

Cited by 16 publications

(7 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Table 3 shows a summary of the papers by Safarrazavi Zadeh et al (2019) and Karimi Chahartaghi et al (2019), who investigated semicircular & sinusoidal labyrinth weirs and arched PKW, respectively. These studies reported

C_{d} = 0.4 - 0.85

and

C_{d} = 0.9 - 1.25

, respectively.…”

Section: Resultsmentioning

confidence: 99%

“…Karimi Chahartaghi, Nazari, & Mahmoodian Shooshtari (2019) studied the effect of the parapet wall and its effect on the PKW's hydraulic performance, stating that the parapet wall results in a 10% improvement of the hydraulic performance. Safarrazavi Zadeh et al (2019) conducted an experimental study of the flow passing over sinusoidal and semicircular labyrinth weirs. They proposed empirical equations for estimating C d .…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Experimental study on the discharge coefficient of triangular piano key weir*

Sanami

Afshar

Saneie

2021

Irrigation and Drainage

View full text Add to dashboard Cite

The present study aims to experimentally evaluate the hydraulic characteristics of a B-type triangular piano key weir (PKW). Equations are proposed for estimating the discharge coefficient (C d ) of type B triangular PKW. Nine PKW models were tested, and the discharge coefficients were obtained. To determine the PKW efficiency, in each flow condition, the experiment was repeated for a linear weir having the same height as the PKW. In particular, the flow rate of the triangular PKW was up to three times higher than that of the linear weir. Studying the flow behaviour showed that the sloping triangular surface of the PKW helps with the quick transfer of flow from the channel bed, especially in the outside keys. In addition, increasing the dimensionless parameters h/L e and h/P reduces the discharge coefficient in the weir. Empirical equations are presented for the triangular PKW discharge coefficient. For the regression analysis, analysis of variance was performed to list the most important variables. Subsequently, by performing sensitivity analysis, the most important dimensionless parameter for estimating the discharge coefficient was obtained. The group method of data handling was applied to the data to achieve higher accuracy. Finally, uncertainty analysis was conducted using the asymmetric loss function.

show abstract

C_{d} = 0.4 - 0.85

and

C_{d} = 0.9 - 1.25

, respectively.…”

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Experimental study on the discharge coefficient of triangular piano key weir*

Sanami

Afshar

Saneie

2021

Irrigation and Drainage

View full text Add to dashboard Cite

show abstract

“…They reported that the trapezoidal piano key weir discharge coefficient was significantly higher than that of the linear and labyrinth weirs. Razavizadeh et al [14] examined the flow passing the sinusoidal and semicircular labyrinth weirs and provided accurate equations for calculating and determining the discharge coefficient. By evaluating the flow characteristics and discharge coefficients of symmetric and asymmetric triangular weirs, Karimi et al [15] indicated the higher discharge coefficient of the asymmetric triangular weir relative to the symmetric triangular weir.…”

Section: Introductionmentioning

confidence: 99%

Laboratory Study of the Hydraulic Performance of the A-Type Triangular Piano Key Weir

Alizadeh Sanami,

Ghaderi,

Alizadeh Sanami

et al. 2023

Water

View full text Add to dashboard Cite

A piano key weir (PKW), a new type of weir aiming to increase the discharge capacity of an existing dam, was recently designed. Despite a large body of research in this field, only a few studies were conducted on A-type triangular piano key weirs (TPKW) in straight channels. In this context, this present research sought to study the flow regime, stage–discharge relationship, and discharge coefficient. Experiments were carried out using nine TPKW models and three linear weirs (LW) as the control weirs. The results indicated that the triangular piano key weirs are capable of passing a higher discharge in similar laboratory conditions compared to linear key weirs due to their longer length. For a given h/P ratio (h is the water head over the weir crest, and P is the weir height) and constant length (Le), an increase in the weir height from 0.07 m to 0.15 m decreases the discharge coefficient by approximately 20%. From sensitivity analysis, the most influential parameters for the tested TPKW models are the h/Le dimensionless ratio, followed by the P/Le and Fr. Moreover, the discharge coefficient has a reverse trend when the dimensionless parameters h/P, h/Le, and Froude number are increased. However, with decreasing h/Le, the discharge coefficient of TPKW tends to that of a broad-crested weir because of local submergence. It is expected that the results obtained will be a reference for researchers who work in this field.

show abstract

“…It is usually made by placing linear weirs in a zigzag pattern and folding them in plan view. Because labyrinth weirs are usually made up of repeated simple shapes (cycles) in plan-view, such as half-circular, circular, triangular, rectangular, and trapezoid (trapezoidal) shapes, both their design and construction are very cost-effective [5][6][7]. The discharge, head of water flowing over the weirs, and weir geometry are the elements that influence their performance [4,8].…”

Section: Introductionmentioning

confidence: 99%

Characteristics of Flow over Rectangular Labyrinth Weirs with Round Corners

et al. 2021

View full text Add to dashboard Cite

The hydraulic performance of round-cornered rectangular labyrinth weirs with varying weir heights and effective lengths has not been explored in the existing literature to the authors’ knowledge. The purpose of this experimental study was to see how the height and effective length of round-cornered rectangular labyrinth weirs affect their discharge efficiency. Nine flat-crested rectangular labyrinth weirs made of high-density polyethylene (HDPE) were tested in a rectangular flume under various discharges to fulfill the goals of this study. The discharge coefficients for the weirs were then calculated. The hydraulic efficiency of weirs with round corners increases as the weir height (P) increases, according to the findings; however, with effective length of the weir to channel width ratios (LC/B) ≤ 1.78, the effect of the weir height diminishes. For the HT/P ranges used in this study, 0.1 ≤ HT/P ≤ 0.65, the round-cornered rectangular labyrinth weirs with higher LC/B ratios (greater M values) showed improved hydraulic efficiency. Furthermore, the effects of the round-cornered rectangular labyrinth weirs’ headwater inflation can be mitigated by increasing the effective length of the weirs;by increasing M values (LC/B ratios). Using multiple linear regression analysis, a satisfactory correlation equation was found between discharge coefficients of round-cornered rectangular labyrinth weirs, CB, and the other parameters, LC, P, and h.

show abstract

Experimental study on flow over sinusoidal and semicircular labyrinth weirs

Cited by 16 publications

References 26 publications

Experimental study on the discharge coefficient of triangular piano key weir*

Experimental study on the discharge coefficient of triangular piano key weir*

Laboratory Study of the Hydraulic Performance of the A-Type Triangular Piano Key Weir

Characteristics of Flow over Rectangular Labyrinth Weirs with Round Corners

Contact Info

Product

Resources

About