Small Cylinder Research Articles

Designing ‘free’ spaces for children with disabilities

As many individuals now spend a large proportion of their time in virtual worlds, what is the value of real space in the 21st century? And for children especially, what are the dimensions of a physical area or expanse that promote health and well-being, support learning and development, and encourage play and creativity? In reviewing the literature over the past few decades, there are a few seminal papers. Notably, Wade and Ellis1 manipulated playgrounds to explore the play of children in two environments. One came with a large amount of apparatus to promote physical activity (climbing frames, cargo nets, hollow tubes, etc.); another equipped with only a steel horse, and small wooden beam and cylinder. Using heart rate telemetry and observations, the findings showed that group size (numbers of children) provoked greater physical activity than the highly-equipped environment, once the initial novelty of the equipment had ceased. A more recent study considered the nature of playground equipment and risk exposure and impact on physical activity and play.2 The materials utilized in the intervention schools were moveable, low-cost, and/or recycled, such as car tyres, Styrofoam boxes, or milk crates. Items were chosen to encourage cooperation and multi-purpose play through challenging, creative, and/or sensory experiences. New materials were added every 3 weeks to maintain novelty. Children in the intervention schools were found to engage in approximately 12% more moderate to vigorous physical activity, measured via accelerometers, with indications of sustained benefits at 2 years. Extending the concept of playgrounds to the natural environment, access to nature, particularly green spaces (grass, trees, parks, forests, etc.) and blue spaces (lakes, rivers, coastal water, etc.) has been associated with better mental health.3 The wonders and beauty of nature are difficult to quantify, but include unexpected pleasures such as coming upon a strip of daffodils (as in Wordsworth's poem I wandered lonely as a cloud 1807) or hearing birdsong whilst smelling spring blossom. These multi-sensory experiences do not necessarily require physical activity, but only space and time in which to appreciate the surroundings. In this respect an investigation of the leisure activities of children with cerebral palsy showed that going for a walk or a hike were recreational activities in which more than 50% participated.4 While most participants in this study had more mild movement restrictions and/or were independently ambulatory, why should those without independent mobility not also enjoy access to the natural environment? These studies highlight some interesting points with respect to the use of open spaces and the freedom for children with disabilities to explore these spontaneously. Moveable items in playgrounds and outdoor activities in natural environments are commonly considered as risky due to more unpredictable usage and hazards.2 Safety-conscious societies may thus inadvertently be contributing to increased risks to health and well-being by limiting these experiences. Our efforts to design spaces to encourage participation and engagement could in fact constrain countless aspects of spontaneity and limit creative play and enjoyment of various spaces. There are opportunities to exploit nature's potential for enjoyment and creativity, alongside enhancement of play and physical activity for young people with more restricted mobility. A recommendation is therefore made to include a sixth ‘F’ word in child disability interventions:5 freedom. This includes the freedom to choose, freedom to be, and freedom to enjoy the moment. Initiating occasions to engage with nature and allow participation in open environments with unstructured activities may be more difficult to orchestrate for children and young people with disabilities and their families, but this should not stop us from trying. The design of virtual spaces that recreate the multi-sensory and emotional experiences of nature will be more of a challenge.

Preliminary Assessment of a Microwave System to Detect Contrast Enhancing Agents.

This paper presents a preliminary study of the impact of potential contrast enhancing agents on a 2-port microwave imaging system. To this end, we have conducted microwave measurements inside a dual cylindrical tank, comprised of an outer and inner cylinder filled with high and low loss liquids, respectively. A third smaller cylinder inside the low loss filled tank represents a target. The target materials consisted of safflower oil, water, PEGylated zinc oxide nanoparticles dispersed in water, and saline with varying concentrations of salt. To benchmark our experimental results, we have also performed accurate numerical simulations of the system under three target scenarios: safflower oil, water, and PEGylated zinc oxide suspension. Our results show that the difference in received signal strength in scenarios with and without PEGylated zinc oxide nanoparticles in our 2-port system was comparable to measurement error. However, with the use of varying concentrations of saline solutions as a target, we have observed a significant difference in received signal strength.

Effect of distal interphalangeal joint fusion of the index or middle finger on the grip or finger force and load distribution in the hand

Due to the functional coupling of adjacent finger joints and the quadriga effect of the flexor digitorum profundus an influence of the grip pattern of the hand after fusion of a distal interphalangeal joint (DIPJ) is assumed. Two patients with DIPJ II- fusion and 8 patients with DIPJ III- fusion due to a posttraumatic osteoarthritis, but without any other pathology of both hands were assessed on average 55 (17-121) months postoperatively by manugraphy. Using three sizes of cylinders the total grip force and the load distribution of the hand and each finger were measured. The grip pattern was analyzed by 2D-graphs. The results of the affected hand were compared to the healthy opposite side. The consolidation of the DIPJ arthrodesis was confirmed and the angle of the joint fusion measured by radiographs. Patients rated their pain in rest or under strain by a visual analogue scale. The total grip force of the affected hand compared to the opposite side was 93 % for the small cylinder, 97 % for the middle, and 96 % for the large cylinder. Both patients with a DIPJ II- fusion neglected the index finger considerably and had a remarkably weak grip force (68/62/68 % for the 3 cylinders respectively). The grip pattern of all fingers has changed. Eight patients with DIPJ III- fusion averaged 99/106/103 % grip force. In six of them, the affected hand was stronger than the opposite hand when using the middle cylinder. The finger force of the middle and ring finger was reduced, but of the index and little finger increased. Five patients had a striking peak of local pressure at the fused DIPJ III.The angle of the fused DIPJ averaged 6° (0-21°) for all patients. Pain was rated on average 1.4 (0-5) at rest and 2 (0-8) with strain. Both aspects were not found to influence the grip force or the load distribution. After DIPJ- fusion of the middle finger its finger force is reduced; but, the total grip force is compensated by an increased finger force of the index and little finger. Despite limitations due to the small number of patients, a DIPJ II- fusion might have a considerable effect on grip force and load distribution of the hand rather due to omitting this finger than purely biomechanical effects.

Effect of electron-RBM phonon interaction on conductance of metallic zigzag carbon nanotubes

We use the energy analysis as a perturbative method to study the effect of electron-radial breathing mode (RBM) phonon interaction on the electrical conductance of long metallic zigzag carbon nanotubes (CNTs). The band structure of zigzag CNTs is calculated by exerting zone-folding method on relations derived by using the nearest neighbor approximation of tight-binding expression for the π bands of graphene. The small hollow cylinder model, with two different approximations, is used to obtain the RBM frequency in our calculation. As the result, we have calculated the effects of electron−RBM phonon interaction on the conductance of zigzag CNTs. It has been observed that current is a step−like function of bias voltage due to the absorption or emission by electron injection in the system. Moreover, the dependence of the conductance to the temperature in low bias and high bias voltages has been studied. In this paper, we propose a simple and useful method for phonon spectroscopy. Also, since RBM mode determines the geometry and structure of CNT, this approach can be used for characterization of CNTs.

New shape function solutions for fracture mechanics analysis of offshore wind turbine monopile foundations

Offshore wind turbines are considered one of the most promising solutions to provide sustainable energy. The dominant majority of all installed offshore wind turbines are fixed to the seabed using monopile foundations. To predict the lifetime of these structures, reliable values for shape function and stress intensity factor are needed. In this study, a new equation is developed through finite element simulations which have been performed for a wide range of monopile geometries with different dimensions, crack lengths and depths, to evaluate shape function and stress intensity factor solutions for monopiles. The new solutions have been verified through comparison with the existing solutions provided by Newman & Raju for small hollow cylinders. The empirical shape function solutions developed in this study are employed in a case study and the results have been compared with the existing shape function solutions. It is found that the old solutions provide inaccurate estimations of fatigue crack growth in monopiles and they underestimate or overestimate the fatigue life depending on the shape function solution employed in the structural integrity assessment. The use of the new solution will result in more accurate monopile designs as well as life predictions of existing monopile structures.

Micellization in binary biosurfactant/synthetic surfactant systems: Effects of temperature and hydrophobic group structure of alkyl benzenesulfonate

Micellization mechanism of biosurfactant/synthetic surfactant systems is essential in predicting their industrial applications. Biosurfactant, [Glu1,Asp5]-C15 surfactin, mixing with three isomers of sodium cetyl benzenesulfonate (SCBS) with benzenesulfonate attached at the 2nd, 5th, 8th carbon on the alkyl chain (abbreviated as 2-SCBS, 5-SCBS, and 8-SCBS), constituted the binary biosurfactant/synthetic surfactant systems in this work. Effects of mixing ratios, temperature, and hydrophobic structures of SCBS on micellization process were investigated by surface tensiometry, steady state fluorescence measurements, dynamic light scattering, and small angle neutron scattering. The results showed that at 60 ℃ synergism in micellization occurred in surfactin/2-SCBS and surfactin/5-SCBS binary systems, while antagonism appeared in surfactin/8-SCBS binary systems. Molecular interaction in mixed micelle at 60 ℃ turned from strong attractive to strong repulsive with the benzenesulfonate moving from the end to the middle of the alkyl chain. Surfactin exhibited weak interaction with both 5-SCBS and 8-SCBS at 25 ℃. Mixed surfactin/2-SCBS micelles were formed in spherical cylinders with more hydrophobic core and within 66 Å. Mixed surfactin/5-SCBS micelles and mixed surfactin/8-SCBS micelles showed similar morphology evolutions at 25 ℃, long elliptical cylinders transformed into small spherical cylinder by reducing both length and radius ratio of cross section with increasing surfactin mole fraction.

KINETIC PROPERTY OF A PRESSURE VESSEL MADE FROM CFRP FABRICATED A FILAMENT WINDING METHOD

Since the specific strength and the specific elasticity of carbon fiber reinforced plastics (CFRPs) are the greatest in practical materials, they are used abundantly in transport structures. This CFRP can also be used for a pressure vessel which stores liquid hydrazine, the required burst pressure is approximately 22MPa. Many researchers have been studying pressure vessels made from a CFRP fabricated by a filament winding (FW) method.
 In order to acquire the fundamental mechanical properties of a CFRP container, the small cylinder made from CFRP fabricated by the spiral winding type FW method is designed and manufactured. The winding angle of a carbon fiber of this cylinder is ±45 degrees. The plastic deformation of this cylinder generates from the strain range of 0.7%. So as to confirm by the analytical method that a small tank made from CFRP fabricated by the FW method can be utilized as a tank for liquid hydrazine, an analysis model is created. Since the pressure to which the strain of this CFRP tank reaches to 0.7% is approximately 35MPa, this small tank can be used as a fuel tank for micro satellites.

Steady viscoelastic flow around high-aspect-ratio, low-blockage-ratio microfluidic cylinders

We employ a state-of-the-art microfabrication technique (selective laser-induced etching, SLE) to produce microfluidic cylinder geometries that explore new geometrical regimes. Using SLE, two microchannels are fabricated in monolithic fused silica substrate with height H=2 mm and width W=0.4 mm (aspect ratio α=H/W=5) containing cylinders of radius r=0.02 mm (blockage ratio β=2r/W=0.1), centered at the channel mid-width, W/2. An ‘sc’ channel contains a single cylinder, while a ‘dc’ channel contains two axially-aligned cylinders separated by a distance L=1 mm (L=50r). Compared with cylinder geometries fabricated by soft lithography (which typically have α ≪ 1 and β ≳ 0.5), these rigid glass devices provide a quasi-two-dimensional flow along the direction of the cylinder axis and also more clearly reveal the effects of the strong extensional wake regions located at the leading and trailing stagnation points. Using flow velocimetry and quantitative birefringence measurement techniques, we study the behaviour of a well-characterized viscoelastic polymer solution in flow around the cylinders. The small cylinder radii result in low inertia and very high elasticity numbers El ≈ 2400. For the sc device, we report strong flow modification effects around the cylinder as the flow rate is incremented. This is associated with the deformation of polymer molecules primarily in the upstream wake region, leading to the onset of a purely elastic flow asymmetry upstream of the cylinder. Stretched polymer molecules are advected around the cylinder and relax downstream of the cylinder, resulting in an extremely long elastic wake extending for > 300r downstream. In the dc channel, at lower flow rates, similar flow modification effects are observed to develop around, and downstream of, both cylinders. However, at higher flow rates the wake of the first cylinder extends > 50r downstream, and begins to interact with the second cylinder. The second cylinder becomes encapsulated by the wake of the first and is effectively obviated from the flow field. The results will be of relevance to understanding practical applications of viscoelastic fluids, for example in particle suspension and porous media flows, and also for benchmarking against numerical simulations using viscoelastic constitutive models.

Accumulation of heavy particles in a circular bounded vortex flow: Parameter influence and comparison

In this work, the accumulation behavior of heavy particles in a circular bounded viscous vortex flow has been explored by an Euler–Lagrange CFD model. Inter-particle and particle-wall collisions are resolved by a hard-sphere model. Effects of Stokes number, the size and the location of the small rotating cylinder are investigated under both one-way and two-way couplings. Results show that, under one-way coupling, most particles will accumulate at one point inside the domain and the accumulation point will move farther away from the stagnation point of the flow field as Stokes number increases. However, under two-way coupling, there is no accumulation point inside the domain. Instead the majority of particles accumulate on the circular wall. As Stokes number enhances, more particles will accumulate on the wall under both one-way and two-way couplings. The slight change of the rotating cylinder's size has little influence on the results, implying the reliability of using the small rotating cylinder to induce the vortex flow. However, the variation in the rotating cylinder's location has a significant impact on the results. As the small cylinder moves farther away from the center of the circular domain, the accumulation point can extend to an accumulation circle under one-way coupling, and less particles will accumulate on the wall under both one-way and two-way couplings.

Experimental study on the packing densification of mixtures of spherical and cylindrical particles subjected to 3D vibrations

ABSTRACTTo identify the dense packing of cylinder–sphere binary mixtures (spheres as filling objects), the densification process of such binary mixtures subjected to three-dimensional (3D) mechanical vibrations was experimentally studied. Various influential factors including vibration parameters (such as vibration time t, vibration amplitude A, frequency ω, vibration acceleration Γ) as well as particle size ratio r (small sphere vs. large cylinder), composition of the binary mixtures XL (volume fraction of cylinders), and container size D (container diameter) on the packing density ρ were systematically investigated. The results show that the optimal vibration parameters for different binary cylinder–sphere mixtures are different. The smaller the size ratio, the less vibration acceleration is needed to form a stable dense packing. For each binary mixture, high packing density can be obtained when the volume fraction of large cylindrical particles is dominant. Meanwhile, increasing the container size can decrease the container wall effect and get higher packing density. The proposed analytical model has been proved to be valid in predicting the packing densification of current cylinder–sphere binary mixtures.

Grasping force estimation in robotic forceps using a soft pneumatic actuator with a built-in sensor

In this paper, we propose a forceps grasper using a soft actuator that can estimate grasping force. The grasper consists of a small cylinder and a slider-crank mechanism embedded at the tip of the forceps. A pneumatic soft actuator made of silicone is fabricated and inserted in the cylinder. The grasper is actuated by inflating the soft actuator. It causes no leakage of air, as well it is lightweight and disposable. The developed soft actuator has a built-in strain gauge to measure the displacement of the actuator. By combing the measurements of the strain gauge and the internal pressure, it can estimate the grasping force. We investigated the relationship between the air pressure in the soft actuator and the opening angle of the grasper in order to estimate the force without a force sensor. First, the soft actuator is pressurized from 0kPa to 160kPa at intervals of 10kPa, and the opening angle of the grasper is measured for each pressure without any load on the grasper. The linearity of the soft actuator between the pressure and the opening angle is confirmed. Then, the experiment with the same protocol is conducted while the grasper grasps a force sensor. The estimated force and the output of the force sensor are compared to show the effectiveness of the proposed method.

A multi-vision-based system for tube inspection

PurposeGeometric errors are common in metallic bent tubular parts. Thus, tubes should be inspected and fixed before welding with the joints first. After welding, the relative position of the joints is also necessary to be inspected to judge whether the tube can be assembled reliably. Therefore, the inspection plays an important role in the tube’s assembly. The purpose of this paper is to propose a multi-vision-based system designed to inspect the tube and the relative position of the joints.Design/methodology/approachFor the tube inspection, the small cylinders are taken as the primitives to reconstruct the tube using the multi- vision-based system. Then, any geometric error in the tube can be inspected by comparing the reconstructed models and designed ones. For joints’ inspection, authors designed an adapter with marked points, by which the system can calculate the relative position of the joints.FindingsThe reconstruction idea can recognise the line and arc segments of a tube automatically and resolve the textureless deficiency of the tube’s surface. The joints’ inspection method is simple in operation, and any kinds of joints can be inspected by designing the structure of the adapters accordingly.Originality/valueBy experimental verification, the inspection precision of the proposed system was 0.17 mm; the inspection time was within 2 min. Thus, the system developed can inspect a tube effectively and automatically. Moreover, authors can determine how the springback of the arcs behaves, allowing in-process springback prediction and compensation, which can reduce geometric errors in the tubes given the present bending machine accuracy.

Multi-Layer Cylindrical Flame Model for Predicting Radiant Heat Flux from Pool Fire

Pool fires are often reported to induce a series of domino accidents in the process of the storage and transportation of chemical fuels. The primary mechanism for this severe process is the thermal radiation from the pool fire that damages both people and facilities nearby. In this paper, a multi-layer cylindrical flame model is proposed to predict the radiant heat flux field of pool fire, in which the cylindrical flame is divided into multi small cylinders with the same height and different surface emissive powers. The surface emissive power correlation of each small cylinder is developed by considering the variation of the centerline flame temperature and flame emissivity along the axial direction. The atmospheric transmissivity to the thermal radiation is also considered for the new radiation model. Analysis shows that the centerline temperature and each layer height (defined as each small cylinder height) affects the new model prediction to significant and little extent, respectively. Compared with the experimental data, point source model and single cylindrical flame model (e.g. Shokri-Beyler model, Mudan model and classical solid flame model), the proposed new model is more competent to predict radiant heat flux from pool fires.

Process optimization of microalgae cultivation in a bubble-column photobioreactor

A process optimization was performed in this study to obtain the values of the geometry and process parameters that provide an optimum average microalgae concentration in an internally illuminated bubble-column photobioreactor. A phenomenological model of the photobioreactor is used to simulate the process in the reactor. The model considers gas-phase mass balance and liquid-phase mass balances accompanied by the rates of CO2 and nutrient intakes in liquid phase. The process optimization gives the values of the small and large cylinder diameters, the culture height, the inlet air flowrate, the CO2 mole fraction in the inlet air and the initial microalgae concentration that promotes the microalgae growth to 0.773 g/L from 0.2 g/L for less than four days.

DEVELOPMENT AND PERFORMANCE EVALUATION OF OLIVE GREADER

Grading of fruits and vegetables is an important operation affecting quality, handling and storage of produce. Manual grading is costly, time-consuming and inefficient. The food industry relies on a rapid and accurate separation and classification of fruits immediately after harvest before spoilage fruits in this study developed a simple prototype machine for olive fruit separation with a small cylinder type grading machine. Two operating parameters each of four levels were studied. The studied parameters included, riddle revolving speed 25, 40, 55 and 70 rpm (0.366, 0.471, 0.576, and 0.680 m/s), and riddles feeding rates (50, 70, 90 and 110 kg/h). The effect of machine parameters on grading efficiency (%), grading productivity (kg/h) and the mechanical damage percentage, were also considered. Results showed that the machine is quite successful for grading Olive fruits. The best result was obtained at 55 rpm riddles revolving speeds and 90 kg/h riddles feeding rate. At these values, maximum grading efficiency of 93.92% and permissible mechanical damage of Olive fruits 3.42% were obtained. These results proved that, the proper operating parameters corresponded with theoretical considerations as the relevant for machine operation.

A stitching linear-scan method for roundness measurement of small cylinders

This paper presents a stitching linear-scan method for roundness measurement of small cylinders. Differing from the conventional rotary-scan method by a roundness measuring instrument which suffers from challenges in accurately aligning a cylinder with the rotational datum axis when the cylinder has a small dimension, the stitching linear-scan method, by which the roundness profile of a small cylinder is obtained by stitching a series of arc profiles around the cylinder circumference linearly scanned by a surface form stylus profilometer, makes it easy in alignment of the small cylinder for roundness measurement. Experiments are presented to demonstrate the stitching linear-scan method.

Turbulent convection of liquid sodium in an inclined cylinder of unit aspect ratio

Turbulent convection of liquid sodium (Prandtl number Pr = 0.0093) in a cylinder of unit aspect ratio, heated at one end face and cooled at the other, is studied numerically. The flow regimes with inclination angles β = 0°, 20°, 40°, 70° with respect to the vertical are considered. The Rayleigh number is 1.5 × 107 . Three-dimensional nonstationary simulations allow one to get instant and average characteristics of the process and to study temperature pulsation fields. A mathematical model is based on the Boussinesq equations for thermogravitational convection with use of the LES (large-eddy simulations) approach for small-scale turbulence modeling. Simulations were carried out with a nonuniform numerical grid consisting of 2.9 × 106 nodes. It is shown that the flow structure strongly depends on β. The large-scale circulation (LSC) exists in the cylinder at any β. Under moderate inclination (β = 20°), the strong oscillations of the LSC orientation angle with dominant frequency are observed. Increasing the inclination up to 40° leads to stabilization of the large-scale flow and there is no dominant frequency of oscillations in this case. It is shown that more intensive temperature pulsations occur at small cylinder inclinations. At any β the regions with intensive pulsations are concentrated in the areas along low and upper cylinder faces. The maximum values of pulsations occur in the area close to lateral walls, where hot and cold fluid flows collide. The intensity of temperature pulsations decreases with increasing distance from the lateral walls. The Reynolds number which characterizes the total energy of the flow reaches its maximum value at β = 20° and then decreases with increasing β. The mean flow has maximum intensity at β = 40°. Turbulent velocity pulsation energy decreases monotonically with increasing inclination angle. It is shown that the inclination leads to an increase in heat transfer along the cylinder axis. The Nusselt number at β = 40° is 26% higher than that in the vertical cylinder.

Experimental Investigation of the Cooling Capacity of Gaseous Carbon Dioxide in Free Jet Expansion for Use in Portable Air-Cooling Systems

This paper investigates the possibility of using the free expansion of gaseous CO2 in portable air-cooling systems. The cooling capacity of the gaseous CO2 free jet expansion was calculated using three different approaches and the results showed that the simplified calculations would give approximated cooling values with an 11.6% maximum error. The mass flow rate, upstream pressure and cooling capacity of the gaseous CO2 decreased with time. A maximum 48.5 watts of cooling was recorded at minute 4 and a minimum value of 10.4 watts at the end of the test. The drop in cooling capacity is due to the evaporation of the liquid CO2 inside the small cylinder which cools the two-phase CO2 mixture and causes a pressure drop (from 6 MPa to 2.97 MPa), which also affects the mass flow rate of gaseous CO2 exiting the orifice (from 0.56 g/s to 0.24 g/s). If this cooling technique is to be considered in portable compact-cooling systems, the mass, pressure and cooling capacity drop with time must be solved. One of the solutions could be to cover the cylinder with a heating coat to compensate for the heat absorbed by the evaporation of the liquid CO2.

Production and Characterization of Glass-Ceramic Materials for Potential Use in Dental Applications: Thermal and Mechanical Properties, Microstructure, and In Vitro Bioactivity

Multicomponent silicate glasses and their corresponding glass-ceramic derivatives were prepared and tested for potential applications in dentistry. The glasses were produced via a melting-quenching process, ground and sieved to obtain fine-grained powders that were pressed in the form of small cylinders and thermally treated to obtain sintered glass-ceramic samples. X-ray diffraction investigations were carried out on the materials before and after sintering to detect the presence of crystalline phases. Thermal analyses, mechanical characterizations (assessment of bending strength, Young’s modulus, Vickers hardness, fracture toughness), and in vitro bioactivity tests in simulated body fluid were performed. On the basis of the acquired results, different potential applications in the dental field were discussed for the proposed glass-ceramics. The use of such materials can be suggested for either restorative dentistry or dental implantology, mainly depending on their peculiar bioactive and mechanical properties. At the end of the work, the feasibility of a novel full-ceramic bilayered implant was explored and discussed. This implant, comprising a highly bioactive layer expected to promote osteointegration and another one mimicking the features of tooth enamel, can have an interesting potential for whole tooth substitution.

A quasi-cloaking phenomenon to reduce the wave drift force on an array of adjacent floating bodies

The mooring of offshore floating structures, such as offshore platforms, in large waves against drift forces and rotational moments is a challenging problem in offshore engineering. To accurately investigate such problems, called positioning problems, the time-averaged steady forces of the second order known as the wave drift forces must be taken into account. Fortunately, a cloaking phenomenon occurs under certain conditions and dramatically reduces the wave drift force acting on such a floating body, as previously reported by several researchers. In the diffraction problem of water waves, cloaking refers to the condition where there is no scattering in the form of radial outgoing waves. The reduction of wave drift force on a truncated cylinder with the occurrence of cloaking phenomenon has been numerically and experimentally confirmed. In this paper, the arrangement of several small circular cylinders at regular intervals in a circle concentric with a fixed floating body is considered as an effective means of reducing the wave drift force. Using a combination of a higher-order boundary element method (HOBEM) and wave interaction theory, the influences of the geometric parameters of the outer surrounding cylinders on the wave drift force and the total scattered-wave energy are systematically investigated and discussed. A quasi-cloaking phenomenon is first found and reported in the present study, which is beneficial and flexible for application in practical engineering. More than one quasi-cloaking trigger (where a trigger is an occurrence condition) can be found simply by varying the distance between the inner and outer floating bodies.