Drop Height Research Articles

Study on the Impact Damage Characteristics of Transplanting Seedlings Based on Pressure Distribution Measurement System

Collision is one of the main causes of mechanical damage to the seedling during transplanting. To reveal the impact damage characteristics of plug seedlings, the kinetics equations of seedling collision were established based on Hertz’s contact theory, and the kinematic characteristics, elastoplastic deformation, and collision damage during seedling collision were analyzed using high-speed photography. Using the Tekscan pressure distribution measurement system, the significant levels of various factors that affect impact peak force (IPF) and damage of seedling pot (DSP) were studied, the change rule of contact pressure distribution of seedlings under significant factors was measured, and a regression model between IPF and DSP was established. The results showed that collision material, drop height and seedling pot size had significant effects on IPF and DSP. The contact pressure area of different collision materials from large to small was soil block, steel, and ABS plastic. The contact pressure area of seedlings of different pot sizes was big, medium, and small in descending order. At a dropping height of 50~350 mm, a contact pressure > 10 kPa accounted for the major contact pressure area, which is the main reason for collision damage of the seedling pot. Linear regression models between IPF and DSP under different factors were established, and the determination coefficients (R2) were 0.98 and 0.94, respectively. The results provided a theoretical basis for understanding the collision damage mechanism of the plug seedling and how to reduce damage during transplanting.

Effects of cushion box and closed let-down ladder usage on impact damage to corn kernel during handling.

The main purpose of this study was to evaluate the effects of the cushion box and closed let-down ladder usage in minimizing mechanical damage to corn kernels during free fall. Kernels from a single lot of cultivar KSC 705 were evaluated for percentage of breakage using three drop methods (free fall, with cushion box, and with closed let-down ladder) at five different moisture contents (10%, 15%, 20%, 25%, and 30%), and three drop heights (5, 10, and 15 m). The results showed that the drop methods had a significant effect on the breakage sensibility of kernels. Sample kernels dropped without a ladder (free fall) had a significantly higher average percentage breakage of 13.80%. In the use of the cushion box, the average kernel breakage was calculated to be 11.41%, which was decreased by about 17% more than the free fall. Sample kernels dropped with the closed let-down ladder had a lower average breakage of 7.26%, which showed that the closed let-down ladder significantly helped to reduce mechanical damage to corn kernels by about 47% comparing free fall and by about 37% than the use of the cushion box. The amounts of kernel damage increased significantly with increasing drop height and decreasing moisture content, but the use of the cushion box and closed let-down ladder systems somewhat reduced the adverse effect of the above factors. To minimize mechanical damage to kernels as they fall into the bin, a grain let-down ladder should be installed in the bin so that it can receive kernels from the filling spout with minimum damage. Empirical models were developed for the dependency of damage to corn kernels due to the impact caused by free fall on the drop height and moisture content at different drop methods.

Bond behavior of an ultra-high performance concrete-filled anchorage for carbon fiber-reinforced polymer tendons under static and impact loads

To investigate the bond behavior of an ultra-high performance concrete (UHPC)-filled bond-type anchorage for carbon fiber-reinforced polymer (CFRP) tendons, both static tensile tests and impact tests were performed on 20 groups of specimens. The anchorages with embedded lengths of 50, 100, 150 and 200 mm were subjected to the static tension and longitudinal impact loads with drop heights of 150, 300, 600 and 900 mm. During the tests, the longitudinal tension and slip of the anchorage were obtained, and the effect of anchorage length and loading rate on the bond behavior was discussed. The results show that in the static tests, slip failure occurred for the anchorages with lengths from 50 to 150 mm, and CFRP bar ruptured as the length raised to 200 mm. When subjected to impact loads, slip failure was observed for all specimens. The damages on the CFRP bar to UHPC interface under impact loads were slighter than those under static tension, and correspondingly the dynamic bond strength was approximately half of the static one owing to the weakened mechanical interlocking. With increasing the embedded length, the bond strength and slip increased due to the radial constraining effect of outside steel tube. Based on the experimental results, a strain rate-dependent function was proposed to quantify the retention of bond strength under impact loads, and prediction formulas were established for determining the dynamic bond strength and critical embedded length of the bond-type anchorage.

An experimental analysis of component contributions to shock absorption performance in third generation sport artificial turf

The increasing use of artificial turf across all levels of sports play has been hypothesized to contribute to an increase in athlete injuries. Current testing standards evaluate the shock absorbing performance of artificial turf surfaces through a single measure of acceleration after a drop test impact. However, these standards focus on the performance of the aggregate turf system, thereby neglecting the component-level contributions of the shock pad, carpet, and infill constituents. The purpose of this study was to explore a novel testing methodology that has the potential to isolate first-order and second-order contributions of components to total system performance. Various subsystems of the traditional, three layer artificial turf were treated as energy absorbing surfaces. A series of no-fatigue and fatigue tests were performed using a custom-built apparatus to characterize each energy absorbing surface at five different drop heights. During no-fatigue testing, it was found that the complete three-layer system outperformed all subsystems by mitigating resultant acceleration and force compared to the baseline. However, any energy absorbing subsystem that contained rubber infill outperformed any subsystem that included shock pad, the designated energy dissipating layer in third generation artificial turf. For fatigue testing, it was observed that energy absorbing surfaces began to deteriorate in as few as 20 impacts. In comparison to existing standards, the inclusion of a second data acquisition instrument yielded more accurate calculations of shock absorption. By capturing an input and output measurement during the impact, calculation of the surface’s characteristic transfer function is attainable and therefore, more information in gleaned from the impact test. Additional research is required to be able to deploy this testing methodology on-site, with fully installed artificial turf systems.

Mechanical response of paperboard to rapid compression

Abstract ZD-tester is a measurement technique for rapid compression in Z-direction. The strain rate of compression of this device is far beyond the ordinary mechanical testing methods applied in papermaking industries. Thus, it provides insights to the material responses which are relevant to industrial applications, e. g. calendaring, printing, etc where the strain rate ranges from hundreds to thousands per second. A physics model that describes the dynamic process of the probe has been developed, where a linear Maxwell model is used to account for the viscoelasticity of paperboard. The simulation has successfully reproduced both the general features and quantitative details of the experiment. The model reveals that the ratio of the elastic modulus to the viscosity modulus of the material governs the amplitude attenuation while the angular frequency of the striking-rebounding cycle depends mainly on the elastic modulus. The dropping height determines the initial striking velocity but has no direct impact on either attenuation or angular frequency. The model and simulation provided interpretations of both experimental observations and dynamic behaviours of the material. With help of simulation, the impacts of the individual parameters, e. g. the Young’s modulus, E, the viscosity modulus, η, and the drop height, H, were also explored.

Modeling Large-Surface Impact-Induced Damage in Iteratively Characterized Filament-Wound Composite Pipes: A Numerical and Experimental Investigation

With the widespread use of fiber reinforced polymer (FRP) composite pipes, their susceptibility to impact damage remains a significant cause of concern. This work investigates the structural response and damage propagation of glass-fiber reinforced epoxy (GRE) pipes under large-surface low-velocity impacts. A series of drop-weight impact tests of varying heights is conducted and compared to numerical finite element (FE) simulations. Then, plies are individually modeled and assigned with properties obtained from the authors’ earlier work. Utilizing composite failure theories and mixed-mode delamination theories, the simulated structural responses including the load–displacement, strain–displacement response and damage propagation are compared and validated with the experimental results. It was found that the structural response is well predicted at higher drop heights and there is a significant change in damage type and propagation with increasing drop heights. The proposed approach builds on the authors’ earlier work and provides a modeling approach for the prediction of structural response, inter- and intra-laminar damage with just pipe level properties.

Experimental Study on Pot Damage and Contact Stress Distribution Characteristics of Oil Sunflower Plug Seedlings

To reveal the collision damage mechanisms of plug seedlings and improve the quality of seedlings, the kinetics equations of the plug seedlings were established based on the generalized Hertz-theory. The influence laws of different factors on pot damage were obtained through a drop impact test. The Tekscan pressure distribution measurement system measured the collision impact force, and the orthogonal tests were conducted. The test showed that the influence of the collision impact force was on the order of plug specification > drop height > contact material. The Tekscan pressure distribution measurement system measured the change law of contact stress distribution under significant influencing factors. The test results showed that the collision contact area between the plug seedlings and contact materials from large to small was soil, steel, and ABS plastic. The collision contact area between the plug seedlings and other plug specifications was 50 plug, 72 plug, and 105 plug from the largest to the smallest. When the plug seedlings collided with contact materials, the average contact stress between the seedlings and the steel plate ranged from 19.4 kPa to 22.8 kPa. When the plug seedlings of various sizes collided with steel plates, the average contact stress was ordered as 105 plug, 72 plug and 50 plug in descending order. A linear regression model between collision impact force and matrix loss rate under different factors was established based on the pressure data collected by the Tekscan pressure distribution measurement system. This study provides a basis for exploring the impact damage mechanisms of plug seedlings and improving the seedling quality.

Shape of sessile drops at small contact angles

The shape of a sessile drop on a horizontal substrate depends upon the Bond number $Bo$ and the contact angle $\alpha$ . Inspired by puddle approximations at large $Bo$ (Quéré, Rep. Prog. Phys., vol. 68, 2005, p. 2495), we address here the limit of small contact angles at fixed drop volume and arbitrary $Bo$ . It readily leads to a pancake shape approximation, where the drop height and radius scale as $\alpha$ and $\alpha ^{-1/2}$ , respectively, with capillary forces being appreciable only near the edge. The pancake approximation breaks down for $Bo=\textrm {ord}(\alpha ^{2/3})$ . In that distinguished limit, capillary and gravitational forces are comparable throughout, and the drop height and radius scale as $\alpha ^{2/3}$ and $\alpha ^{-1/3}$ , respectively. For $Bo\ll \alpha ^{2/3}$ these scalings remain, with the drop shape turning into a spherical cap. The asymptotic results are compared with a numerical solution of the exact problem.

Speckle projection profilometry used for detecting magnetic circuit drop height of relay with high reflective surface

Aiming at the problem of camera pixel saturation caused by the high reflective area on the metal surface of a relay, we adopt speckle projection profilometry to detect the magnetic circuit drop height of the relay. The main problem is solved through a detailed analysis of characteristics according to different speckle gray values, speckle sizes, and shapes to effectively distinguish the confusion between the speckle reflection spots and background light reflection spots. The enhanced normalized cross-correlation sub-pixel algorithm is used to get a dense matching pair of points of the right and left images, and three-dimensional reconstruction is based on the triangulation parallax principle. The random sampling consensus algorithm and European clustering algorithm are used to segment the point cloud to obtain the core and yoke iron planes and measure the distance between the two planes. We measured two standard blocks with height difference of 1 mm, and the error is within 2% by the proposed method. The correctness is verified through real-time measurement for a magnetic circuit drop height of the relay assembly line.

The energy threshold in dynamic probing

In dynamic probing tests, penetration is closely related to the potential energy of the hammer (nominal energy). This energy stems from the mass and free fall of the hammer after being released from a certain height. Penetration depends on energy, although only on a portion of that nominal energy that is effectively transferred to the rods (ENTHRU) and, more precisely, the energy that reaches the cone (ENTHRUcone). ENTHRU can be measured by monitoring the upper part of the drive rods. To calculate ENTHRUcone, ENTHRU needs to be corrected in three ways. Firstly, the energy loss in the energy transmission through the rods has to be subtracted, as well as the energy loss due to the skin friction of the rods along the soil around them. It is also necessary to add the energy due to the rod weight penetrating the soil. The main hypothesis assumed and later experimentally proved in this paper is based on the fact that ENTHRUcone has to be greater than a certain value or minimum energy (energy threshold: Th) in order to be able to cause penetration. After analyzing more than one hundred blows with different hammer mass and drop height, a small but consistent Th and a linear relationship between energy and penetration beyond it were found. The energy that really produces penetration (ENPEN) will be ENTHRUcone, minus Th. This allows for improved energy corrections and correlations between results from various kinds of penetration tests.

Predictive modeling of drop impact force on concave targets

Impacting drops are ubiquitous and the corresponding impact force is their most studied dynamic quantity. However, impact forces arising from collisions with curved surfaces are understudied. In this study, we impact small cups with falling drops across drop Reynolds number 2975–12 800, isolating five dominant parameters influencing impact force: drop height and diameter, surface curvature and wettability, and impact eccentricity. These parameters are effectively continuous in their domain and have stochastic variability. The unpredictable dynamics of the system incentivize the implementation of tools that can unearth relationships between parameters and make predictions about impact force for parameter values for which there is not explicit experimental data. We predict force due to the impacting drop in a concave target using an ensemble learning algorithm comprised of four base algorithms: a random forest regressor, k-nearest neighbor, a gradient boosting regressor, and a multi-layer perceptron. We train and test our algorithm with original experimental data comprising 387 total trials using four cup radii with two wetting conditions each. Our approach permits the determination of relative importance of the input features in producing impact force and force predictions which can be compared to scaling relations modified from those for flat targets. Algorithmic predictions indicate that deformation of the drop and surface wettability, often neglected in scaling for impact force on flat surfaces, are important for concave targets. Finally, our approach provides another opportunity for the application of machine learning to characterize complex systems' fluid mechanics for which experimental variables are numerous and vary independently.

Effects of impact loads on heated-and-cooled reinforced concrete slabs

The potential collapse of heavy components in fires can cause dynamic loads on slabs triggering a progressive collapse of weakened slabs on lower floors. In this study, three reinforced concrete (RC) slabs heated under ISO-834 standard fire for 30, 45, and 60 min, while one slab used as a control specimen. The effects of impact loads due to the falling weight were studied using the low-velocity impact test on RC slabs. The acceleration of midspans is recorded, and the dominant frequency and crack pattern of the specimens are measured. The experimental results used to verify the finite element (FE) models. A set of parametric studies are conducted to evaluate the peak acceleration, maximum and residual displacement, load, stiffness, and absorbed energy of heated RC slabs. The outcomes of the parametric study are fed into a machine learning model called Multilayer perceptron (MLP). Results showed that the fire duration affects and reduces the peak acceleration and frequency of the slabs. The average reduction for peak acceleration was 23% for all tested slabs. Numerical results revealed that the impact load with a low energy (i.e., low mass and the height of drop) has a weak dependency on the time of exposure and reinforcement ratio. The results of this paper impact the fire safety design of the RC slabs and the evaluations of fire-exposed RC slabs.

High‐Performance and Insensitive DNTF‐DFTNAN Eutectic: Binary Phase Diagram and Characterization

AbstractIn order to hunt for a high‐energy and insensitive eutectic, differential scanning calorimetry (DSC) method was used to investigate the melting process of DNTF‐DFTNAN co‐molten mixtures with different compositions. Based on the experimental T‐x phase diagram, the experimentally extrapolated molar ratio of DNTF‐DFTNAN eutectic mixture is 30.1/69.9, which is consistent with the result from the H‐x phase diagram, and the eutectic point is about 335.5 K, showing that the addition of DFTNAN can effectively reduce the melting temperature of DNTF. The FT‐IR and XRD measurements of raw DNTF, raw DFTNAN and the DNTF‐DFTNAN eutectic indicate that no chemical reaction occurred and the structure of crystal doesn't change during the preparation of the eutectic. The thermal decomposition temperatures at different heating rates and the apparent activation energy of eutectic are basically between DNTF and DFTNAN. The drop height (H50) for the DNTF‐DFTNAN eutectic increases by 27.4 cm (85.1%) compared with that of DNTF, and the detonation velocity decreases only by 0.5 km/s (5.5 %), implying that the DFTNAN can efficiently desensitize the DNTF explosive with a slight energy loss. In addition, the polynomial equations of mechanical sensitivity and detonation velocity with DNTF content were fitted to adjust the detonation performance and sensitivity of DNTF‐DFTNAN co‐molten mixture, which provides an opportunity to design DNTF‐DFTNAN expected melt‐cast explosives.

Investigating Morphology and Breakage Evolution Characteristics of Railroad Ballasts over Distinct Supports Subjected to Impact Loading

The ballast bed constantly degrades under the repeated applications of impact loading exerted by passing trains in terms of the particle size, shape, breakage, fouling, etc., thus significantly jeopardizing the in-service performance and operational safety of ballasted tracks. In this study, the morphology and breakage evolution characteristics of railroad ballasts of single- and multiple-size ranges were investigated from laboratory impact-load tests. Both a concrete block and sand layer were placed to mimic the distinct under-ballast supports. The degradation trends of the typical shape and breakage indices were comparatively quantified for different combinations of ballast particle sizes and shapes, under-ballast supports, impact energies, and number of impact-load applications (N). The results show that both shape and size affect ballast particle breakage, with shape being more influential. The breakage severity of flake-like particles is about 1.5–1.66 times and 1.25–1.5 times higher than those of regular and needle-like particles, respectively. Under impact loading, large and small single-size ballasts degrade mainly by breakage and abrasion, respectively. The modified fouling index (FI) of flake-like particles within 31.5–40 mm is about 3.6 times that of regular particles within 50–63 mm. The shape indices of the ballast particles within 31.5–40 mm exhibit the most profound changes. The severities of the ballast breakage and fines generation (or modified FI) increased by 50% and 74%, respectively, due to the increase in the under-ballast support stiffness by 100 times and the drop height of 80 cm, respectively. The convexity and ballast breakage index (BBI) are promising for quantifying particle-degradation trends, and their statistical correlation found herein is potentially useful for the transition of ballast-bed-maintenance management from the current plan-based scheduling to condition-based upgrading.

Experimental study of slamming pressure for a trimaran section with different drop heights and heel angles

Trimarans may suffer from large motion and strong slamming accompanied by repeated water entry and water exit motions when sailing under severe sea conditions, and the huge instantaneous slamming load is prone to causing local structural damage. In this study, a free-drop water-entry model test of a trimaran section with different drop heights and heel angles was conducted. The motion and slamming pressure under different test conditions were compared, and the evolution of the free surface and flow field was observed using PIV (Particle Image Velocimetry) technology. We found that the peak value of the pressure was proportional to the square of the impact velocity, and that the peak pressure increased with the increasing heel angle on the lower side of the trimaran. Moreover, the flow separation phenomenon was more obvious at higher drop heights and larger heel angles. Finally, a Gaussian distribution function fitting model is proposed to fit the time-history curve of the slamming pressure within the slamming duration time on cross deck. The non-dimensional pressure coefficient and slamming action time under different conditions are summarised, and the fitting form which considers the impact velocity and impact angle in our results shows good agreement with the experimental data.

Influence of height and weight of drop hammer on impact strength and fracture toughness of two-stage fibrous concrete comprising nano carbon tubes

Concrete is the most extensively utilized and cheapest building material. The cracking and fracturing of concrete may cause catastrophic harm to the structures. Advancements in fibrous concretes have recently been emerged to mitigate these issues. Two-Stage Fibrous Concrete (TSFC) is a new cement composite made of fibres with surpassing mechanical properties and exceptional toughness values. The production of TSFC involves packing aggregates and fibres in the molding and filling the gaps between the aggregates with high flowability via the injection of cement grouts. Nevertheless, the influence of TSFC comprising multi-walled carbon nanotubes (MWCNT) on impact strength and fracture toughness requires particular attention since it is yet unexamined. The study was divided into two phases to address this knowledge gap. In the first phase, the influence of drop hammer weight and height on the impact resistance of TSFC were examined. Three different heights 600, 750 and 900 mm and three different hammer weights 9, 7.5 and 6 kg were used to assess the TSFC’s impact strength. The fracture toughness under mode (I and III) and mixed-mode (I/III) of TSFC were evaluated in the second phase. For this, many notched specimens of circular disc shape were cast and tested. TSFC was produced with three different fibres; polypropylene fibre, short steel fibre, and long steel fibre with a dosage of 2.5 % by volume. Additionally, composites were created by adding 0.2 % MWCNT by weight of cement. Findings indicated that the failure impact numbers values of mixtures incorporating polypropylene fibre, short steel fibre and long steel fibre were higher than those of the reference plain mixture by 1444 to 1700 %, 3156 to 3786 % and 4322 to 5357 %, respectively. Adding fibre has a more significant impact on mode I and III crack development, with improvements ranging from 46.1 to 92.2 % for mode I and from 16.4 to 30.0 % for mode III, proving that fibres can substantially increase the TSFC's fracture resistance.

A contribution to rainfall simulator design – a concept of moving storm automation

Abstract. We developed an advanced-design programmable rainfall simulator (RS) to simulate a moving storm rainfall condition. The RS consists of an automated nozzle control system coupled with a pressure regulator mechanism for an operating range of 50 to 180 kPa at a drop height of 2000 mm above the soil flume surface. Additionally, a programmable mobile application was developed to regulate all RS valves. Near natural rainfall conditions were simulated at varying spatial and temporal resolutions in a controlled environment. A soil flume of 2500 mm × 1400 mm × 500 mm was fabricated to conduct different hydrological experiments. The flume was designed to record overland, subsurface, and baseflows simultaneously. This study focused on a detailed analysis of moving storms and their impact on hydrograph characteristics. Experimental results showed a considerable difference in terms of time to peak (tp), peak discharge (Qp), and hydrograph recession for two different storm movement directions (upstream and downstream). Two multiple regression models indicate a statistically significant relationship between the dependent variable (tp or Qp) and the independent variables (i.e. storm movement direction, storm velocity, and bed slope gradient) at a 5 % level of significance. Further, the impact of these moving storm phenomena reduces with the increase in the storm movement velocity.

Effects of cushion box and closed let-down ladder usage on mechanical damage during corn kernel handling: Cracking

Corn kernels have a high susceptibility to mechanical damage due to their large size and mass. The main purpose of this study was to evaluate the effects of the cushion box and closed let-down ladder usage in minimizing mechanical damage to corn kernels during handling. Kernels from a single lot of cultivar KSC 705 were dropped in three methods (free fall, with a cushion box and with a closed let-down ladder) at five moisture contents (10, 15, 20, 25, and 30%), and three drop heights (5, 10 and 15 m) were evaluated for the percentage of various types of cracking and cracks index (CI). The results showed that the drop method had a significant effect on the damaged kernels. Sample kernels that fell without a ladder (free-fall) had a significantly higher average CI of 144.8. In the use of the cushion box, the average cracks index was calculated to be 103.3, which was decreased by about 29% more than the free fall. Sample kernels dropped with the closed let-down ladder had a lower average CI of 51.6, which showed that the closed let-down ladder significantly helped to reduce mechanical damage to corn kernels by about 64% comparing free fall and about 50% than the use of the cushion box. The amounts of kernels damage increased significantly with increasing drop height and decreasing moisture content, but the use of the cushion box and closed let-down ladder systems somewhat reduced the adverse effect of the above factors.

Numerical and predictive analysis of the low-velocity impact response of UD composite plate under a controlled environment

The present paper proposes an investigation and analysis study of a low velocity impact on a unidirectional S2-Glass/Polyester composite plate subject to a controlled environment. A set of simulations of low velocity impact on unaged and aged samples in a bending configuration were carried out. A mass diffusion is studied in order to use its outputs as a predefined field which will be combined with the velocity of the impact loads. The diffusive and mechanical responses, such as moisture concentration, the effect of temperature, energy dissipation and impact force are highlighted and analysed. To ensure the validity of the finite element model, a comparison study has been carried out and compared against experimental investigation founded in the literature. The adopted finite element model performance for the low velocity impacted composite plate under hygrothermal conditions strongly matches with the experimental findings and represents a clear improvement of the model. The impact of the moisture concentration on recorded contact force and energy is highlighted, particularly the delayed contact time and the reduction of the contact forces and the recorded energies intensity. Accordingly, two main factors have affected the contact force responses. These two factors are the drop height and the humidity concentration. An analysis of the maximum contact forces using the design of experiments (DOE) is performed. The effect of both factors namely, the drop height and the humidity concentration, on the response is highlighted as well as the effect of their interaction. The predictive model is highly effective and eases the reproducibility of other mechanical responses.

Effect of Bed Roughness and Negative Step on Characteristics of Hydraulic Jump in Rectangular Stilling Basin

Water flow often releases excess energy after passing through gates and spillways. This energy should be reduced to avoid the destruction of downstream structures. The hydraulic jump, a natural phenomenon, inevitably reduces incoming flow energy. The experiments were carried out in this study to investigate the effect of bed roughness and abrupt negative drops on the characteristics of the hydraulic jump. Also, to investigate the effect of geometric and hydraulic parameters on energy dissipation and location of the hydraulic jump, there was a change in the height of the abrupt drop and roughness for different discharges between 30 and 50 L/s and the Froude numbers were ranging from 4.9 to 9.5. The results showed that increasing the bed roughness causes a reduction of the sequent depth ratio and the relative length of the jump by 16.6% and 20.7%, respectively, and increases the relative energy loss and the bed shear force coefficient by 10% and 31%, respectively. In contrast, increasing the step height causes an increase in the sequent depth ratio and the relative length of the jump by 6.5% and 7%, respectively, and increases the relative energy loss and the bed shear force coefficient by 11% and 3.2%, respectively.