Total Dissipation Research Articles

Heat Generation during Minimally Invasive First Metatarsal Osteotomy: A Cadaveric Study

Category: Bunion; Midfoot/Forefoot Introduction/Purpose: Bunions are one of the most common pathologies treated by orthopedic foot and ankle surgeons. The usage of minimally invasive and percutaneous surgical techniques continues to rise due to evidence of less pain, improved functional outcomes and low recurrence rates. Still, concern regarding heat generation during these procedures, osteonecrosis of bone, and nonunion persists. Literature suggests cool irrigation is superior to room temperature irrigation, but the question remains if irrigation is needed at all. This study evaluates the heat generation during percutaneous bunion surgery and analyzes the use of cooled irrigation compared to no irrigation at all. This study tested the hypothesis that cool irrigation would lead to overall lower heat generation compared to no irrigation at all. Methods: 5 matched paired cadavers (10 legs) were used to simulate MIS first metatarsal distal transverse osteotomy for all trials. Prior to osteotomy, 4 temperature probes were inserted as to the border where the Shannon burr would travel along the osteotomy site (Image 1). Probes were secured by suture and temperature was recorded using K-type thermocouples. All trials were completed using a pulse technique of 20 seconds on, 5 seconds off with a Shannon Burr and fluoroscopic guidance. Trials were complete with continuous cold irrigation (N=5) and without any irrigation at all (N=4). Temperatures were evaluated at baseline, during burring, and after burring to assess total heat generation and dissipation. A two-tailed t-test was used to analyze differences in heat generation and dissipation between procedures completed with irrigation and without irrigation (P < 0.05). Results: 5 cadavers with a mean age of 86.2 were evaluated (10 total simulations, 9 analyzed). Cadavers underwent 1 trial with irrigation, and 1 without on opposite feet. 88.9% of patients showed heat generation below the level of bone necrosis (50 oC). One trial with irrigation temperature rose to 79.1oC. Matching specimen without irrigation had probe failure and no temperature was obtained. Average burr time was 51.2±2.4 seconds with irrigation, and 35±0.5 seconds without. Irrigation was associated with a significant increase in burr time (P=0.002). Average temperature change was 13.62±11.9 and 0.7±0.5 during burring, 7.1±1.8 and 5.8±0.3 after burring in procedures with and without irrigation, respectively. No significant difference was detected between heat generation in irrigated vs non-irrigated procedures (P = 0.371, 0.548). Conclusion: This study found that in a cadaveric model the use of cooled irrigation, compared to no irrigation, did not lead to a significant difference in the heat generation during MIS first metatarsal distal transverse osteotomy. However, 1 out of the 9 samples used in this study showed a heat generation above 50 oC. Additionally, to our surprise the use of irrigation led to a significant increase in burring time. This may be useful information for a surgeon when considering the usage of cooled irrigation to reduce the potential risk of osteonecrosis when performing a MIS first metatarsal distal transverse osteotomy.

Feasibility of utilising waste tyre steel fibres to develop sustainable engineered cementitious composites: Engineering properties, impact resistance and environmental assessment

This study investigates the feasibility of developing sustainable engineered cementitious composite (ECC) with polyvinyl alcohol fibre (PVAF) and recycled tyre steel fibre (RTSF) to reduce the total cost of construction materials and ease the environmental pressure for disposing of waste tyres, putting an emphasis on the engineering properties, impact resistance and environmental assessment. Experimental results reveal that partially replacing PVAF with RTSF can reduce the loss in fluidity and promote flexural performance, while the fibre bridging stress of ECC can reach up to 4.41 MPa because of the enhanced fibre bridging effect. The dynamic compressive properties of ECC present a typical strain rate effect regardless of the fibre content, and the replacement of 0.25 vol% RTSF would cause a further 5.03%–25.55% increase in total dissipation energy within the strain rates of 58.2–124.5 s−1, relative to ECC reinforced by 2.0 vol% PVAF. The synergetic effects of hybrid fibres on dynamic compressive properties of ECC can be explained by the bridging and pull-out effects of PVAF at lower strain rates, as well as the enhanced fibre-to-matrix bonding of hydrophilic RTSF at relatively higher strain rates. Upcycling of waste steel fibres in ECC holds promise as a cost-effective and eco-friendly solution for defence engineering constructions.

A new approach for evaluating photosynthetic bio-hydrogen production: The dissipation rate method

A dissipative rate model is established by using the non-equilibrium thermodynamics method to evaluate photosynthetic bio-hydrogen production process. The mass transfer dissipation rate, chemical reaction dissipation rate and total dissipation rate for the bio-hydrogen production processes with glucose and acetic acid are calculated and analyzed respectively by using the proposed dissipation rate model. When substrate concentration is taken as variable (15 g/L,20 g/L and25 g/L), the total dissipation rate and mass transfer phenomenological coefficient of hydrogen production process with 20 g/L are the lowest, and the maximum dissipation rate is 7.7288J/h. The phenomenological coefficient of chemical reaction is larger at high concentration. When the temperature is variable (298.15 K,303.15Kand308.15 K), the dissipation rate is lowest at 303.15 K and the chemical reaction coefficient is largest and the maximum dissipation rate is 6.0596J/h. In addition, the mass transfer phenomenological coefficient is larger at high temperature. With the initial pH as variable (6.5,7.0,7.5), the maximum dissipation rate of 11.2271J/h is obtained at pH 7.5. At high pH, the mass transfer phenomenological coefficient is large and the chemical reaction coefficient is exactly the opposite. This model can predict the energy dissipation law in the process of photosynthetic biohydrogen production, and provide a theoretical basis for the subsequent process optimization.

Minimum entropy production by microswimmers with internal dissipation

The energy dissipation and entropy production by self-propelled microswimmers differ profoundly from passive particles pulled by external forces. The difference extends both to the shape of the flow around the swimmer, as well as to the internal dissipation of the propulsion mechanism. Here we derive a general theorem that provides an exact lower bound on the total, external and internal, dissipation by a microswimmer. The problems that can be solved include an active surface-propelled droplet, swimmers with an extended propulsive layer and swimmers with an effective internal dissipation. We apply the theorem to determine the swimmer shapes that minimize the total dissipation while keeping the volume constant. Our results show that the entropy production by active microswimmers is subject to different fundamental limits than the entropy production by externally driven particles.

Analysis of the Impact of Parameters of Gravity Heat Pipe Radiator on the Temperature Control of Gangue Hill and Engineering Test

ABSTRACT Deep within coal gangue hills, there is a substantial amount of wasted thermal energy. Prolonged accumulation of these hills leads to significant damage to the atmosphere and soil. Gravity heat pipes, as efficient heat transfer components, can safely, efficiently, and conveniently extract the accumulated heat in gangue hills to achieve effective thermal control. In this study, we first analyzed the optimal height of the heat dissipation fins through a single fin heat dissipation model. Then, we determined the optimum spacing between the heat dissipation fins through analysis with multiple fins. The results showed that when the height of the heat dissipation fins was 80 mm and the spacing between fins was 80 mm, the heat dissipation performance and economic costs were most reasonable. Through an engineering trial conducted for 143 days at the Maotergou coal mine gangue hill, it was found that the average heat dissipation rate of a single gravity heat pipe ranged from 243.52W to 494.32W. The total heat dissipation during the entire experimental process was 54.39 kJ, and the total heat dissipation at the elevation of 890 meters was 1087.71 kJ. This indicates that managing the internal temperature accumulation in coal gangue hills using gravity heat pipes is entirely feasible.

A length scale for non-local multi-scale gradient interactions in isotropic turbulence

Three-dimensional turbulent flows enhance velocity gradients via strong nonlinear interactions of the rate-of-strain tensor with the vorticity vector, and with itself. For statistically homogeneous flows, their total contributions to gradient production are related to each other by conservation of mass, and so are the total enstrophy and total dissipation. However, locally, they do not obey this relation and have different (often extreme) values, and for this reason both production mechanisms have been subject to numerous studies, often decomposed into multi-scale interactions. In general lines, their dynamics and contributions to the cascade processes and turbulent kinetic dissipation are different, which poses a difficulty for turbulence modelling. In this paper, we explore the consequence of the ‘Betchov’ relations locally, and show that they implicitly define a length scale. This length scale is found to be approximately three times the size of the turbulent structures and their interactions. It is also found that, while the non-locality of the dissipation and enstrophy at a given scale comes mostly from larger scales that do not cancel, the non-local production of strain and vorticity comes from multi-scale interactions. An important consequence of this work is that isotropic cascade models need not distinguish between vortex stretching and strain self-amplification, but can instead consider both entities as part of a more complex transfer mechanism, provided that their detailed point value is not required and a local average of reasonable size is sufficient.

Study on the energy evolution mechanism of coal and rock with impact tendency under different strain rates

To explore the strain rate effect of deformation and failure of impact prone coal rock, uniaxial compression tests and triaxial compression tests with different strain rates were carried out. The mechanical properties and impact tendency of impact-prone coal rock were studied, and the energy evolution law and pre-peak energy self-promotion-inhibition mechanism of impact-prone coal rock were obtained. The results show that with the increase of strain rate, the peak strength of coal rock under uniaxial compression decreases gradually, and the peak strength of coal rock under triaxial compression increases first and then decreases, and the impact tendency of coal rock increases first and then decreases. The energy evolution of coal rock under uniaxial compression is mainly divided into four stages: initial energy damage, energy hardening, energy softening and failure. With the increase of strain rate, the total energy and elasticity at the peak point of coal rock under uniaxial compression decrease gradually, and the total energy, elastic energy and dissipation energy at the peak point under triaxial compression increase first and then decrease. The elastic energy promotion coefficient of impact-prone coal rock is much larger than the inhibition coefficient, and the increase of strain rate will promote the generation of elastic energy inside coal rock. The research results can provide reference for the prevention and early warning of dynamic disasters of coal and rock mass with impact tendency.

Quantification of viscous and damage dissipation of bituminous binder and mastic using White-Metzner model

ABSTRACT Bituminous pavement layers are composite in nature, consisting of binder, filler, and aggregates. Understanding the mechanical behaviour of bituminous layers demands investigation of their different material scales, such as the binder, mastic, and mixture scales. While substantial investigation has been carried out on binder and mixture related to fatigue damage, not much research is carried out on mastic. Of the methods used to characterise fatigue damage, energy dissipation is widely used; however, it is complicated due to the presence of other modes of dissipation, such as viscous dissipation. In this study, an attempt is made to separate viscous dissipation and dissipation due to damage for both binder and mastic using a nonlinear viscoelastic fluid model. For this purpose, six types of materials were tested at temperatures of 20 ∘ C and 25 ∘ C, 10 Hz frequency, and five different strain levels spanning the linear and non-linear regimes, for 20,000 cycles. Material parameters for the non-linear White-Metzner model incorporated with the Williamson model were determined for an initial cycle and using these parameters, the viscous component of energy dissipation was determined. Dissipation due to damage was estimated by separating viscous dissipation from total dissipation at every 2000th cycle and based on the evolution of viscous and damage dissipation across cycles, three trends were observed. Based on the trends observed, the influence of strain amplitude, temperature and modifiers on the fatigue resistance of the materials was ascertained.

Reliable operation of an optimal self-scheduling multicarrier system with two alternatives: Multiple renewable utilities or hydrogen facilities

Multicarrier systems (MCSs) have been retrofitted with storage facilities to enhance their resilience to meet the fluctuating demands. Considering the complexity of the systems and the interactions among various carriers, optimal resource allocation is a serious challenge in the sustainable management of energy systems. This study proposes a new self-scheduling MCS to supply power, heating, cooling, and freshwater, without external cooling and nonrenewable heating facilities. Modeled based on circular integration principle, the MCS consists of various subsystems and storage facilities to treat the effluent and digest excess sludge of a wastewater treatment facility. The MCS is optimally designed and scheduled in a two-stage multi-objective optimization to satisfy the demand loads of a small community in two configurations: one with a material conversion unit (MCS-MC) to store and utilize hydrogen, and the other with weather-driven renewable energy units (MCS-RE) for a reliable operation. Accordingly, total annual cost (TAC), total exergy dissipation (nTED), and the mismatch between supply and demand (MSD) are minimized in a multi-objective optimization problem to obtain the optimal capacity of the equipment and the short-term storage facilities are scheduled in the first and second stages, respectively. The results show that the optimal MCS-MC and MCS-RE configurations reduced the TAC, nTED, and MSD by 30.2% and 12.4%, 32.9% and 23.4%, and 55.4% and 48.5%, respectively, compared to the base system. The new utility-free hydrogen-assisted multi-carrier systems are anticipated to substitute present systems with multiple renewable resources.

Turbulent dissipation in the boundary layer of precession-driven flow in a sphere

The energy dissipation in a uniform vorticity flow, such as the flow in a precessing spheroid or the one associated with the earth’s free core nutation, is mainly confined to the boundary layers. However, the thinness of the boundary layer renders it difficult to study the energy dissipation in the turbulent regime, either in laboratory experiments or through direct numerical simulations. Here, we use a local Cartesian model to study the energy dissipation in the boundary layer of a precessing sphere when the flow becomes turbulent, contrasting it with the laminar case. We compute the evolution of the boundary layer over time at individual co-latitudes based on direct numerical simulations using the computational fluid dynamics solver Nek5000. We then estimate the total global dissipation by summing up individual contributions. A comparison with known analytical results in the laminar case validates this approach. We briefly discuss the applications to the lunar and the earth’s core cases.

Damage evolution, brittleness and solidification mechanism of cement soil and alkali-activated slag soil

Alkali-activated materials are environmentally friendly gelling agents that have been intensively studied in soil solidification over a long period of time. Currently, there is little research on the deformation and damage laws of solidified soils during compression failure. This study investigates the energy dissipation mechanism and plastic damage model of Weibull distribution to explore solidified soil under different curing ages, moduli, and cement, ground granulated blast furnace slag (GGBS), and alkali-activator contents to further explore the damage evolution law and elastic-plastic state of alkali-activated slag soil. The destruction of solidified soil is accompanied by energy dissipation, and the damage to a specimen under load can be expressed as the amount of dissipated energy. In this paper, the change rules of the damage variable (D), total dissipation energy (U), elastic strain energy (Ue), and dissipation energy (Ud) of solidified soil during compression are described in detail, and the damage to the solidified soil is characterized using the dissipation energy ratio (Ud/U) and damage variable. Based on the energy dissipation mechanism, a brittleness index (BI) is established considering the pre-peak elastic-plastic state and post-peak load-bearing capacity loss states. The U, Ue, and BI increase with a decrease in the modulus and increase in the curing age and cement, GGBS, and alkali-activator contents, whereas Ud/U and D decrease. D is linearly proportional to Ud/U. The BI and Ud/U demonstrated an exponential correlation. Finally, the influence of the cement, GGBS, and alkali-activator contents are shown to increase through X-ray diffraction (XRD), thermogravimetry (TG/DTG) and nuclear magnetic resonance (NMR) tests. Additionally, the effects of the cement, GGBS, and alkali-activator contents and alkali-activator modulus on the damage variable and brittleness index are explained from a microscopic point of view. The relationships between porosity and Ud/U, D, and BI are established. This study provides a reference value for the characterization of mechanical properties of solidified soil and the relationship between the pore structure and mechanical indexes.

Low-frequency broadband sound absorption based on Cantor fractal porosity

Proposals for new absorber designs for broadband sound absorption are of great interest due to their wide applicability in sound energy control. In this sense, the behavior of an acoustic absorber composed of a panel with slit-type perforations based on Cantor’s fractal is presented. The analytical model for the fractal porosity of the absorber as a function of the initial geometric parameters, the number of iterations, and the fractal dimension was established. The behavior of broadband sound absorption was evaluated theoretically, numerically, and experimentally, in which the predominant total thermal-viscous dissipation in the region of perforations increases as the fractal porosity of the absorber decreases. Furthermore, an experimental broadband sound absorption of 692 Hz (from 382 to 1074 Hz) with a peak amplitude greater than 80% is obtained with the proposed structure presenting a sub-wavelength scale, i.e., λ/27. Finally, this work contributes to the understanding of the use of Cantor’s fractal porosity in the proposal of new absorbers that allow broadband sound absorption at low frequency.

Special Cosserat rods with rate-dependent evolving natural configurations

We present a nonlinear, geometrically exact, and thermodynamically consistent framework for modeling special Cosserat rods with evolving natural configurations. In contrast to the common usage of the point-wise Clausius–Duhem inequality to embody the Second Law of Thermodynamics, we enforce the strictly weaker form that the rate of total entropy production is non-decreasing. The constitutive relations between the state variables and applied forces needed to close the governing field equations are derived via prescribing frame indifferent forms of the Helmholtz energy and the total dissipation rate and requiring that the state variables evolve in a way that maximizes the rate of total entropy production. Due to the flexibility afforded by enforcing a global form of the Second Law, there are two models obtained from this procedure: one satisfying the stronger form of the Clausius–Duhem inequality and one satisfying the weaker global form of the Clausius–Duhem inequality. Finally, we show that in contrast to other viscoelastic Cosserat rod models introduced in the past, certain quadratic strain energies in our model yield both solid-like stress relaxation and creep.

Numerical Dissipation Rate Analysis of Finite-Volume and Continuous-Galerkin Methods for LES of Combustor Flow-Field

A growing body of literature indicates that element-based high-order methods can exhibit considerable accuracy/cost benefit over conventional second-order finite-volume (FV) methods for large-eddy simulations (LES). This may even hold true for complex configurations relevant to industry that involve under-resolving unstructured grids. However, it is not often clear whether the accuracy/cost benefit stems from the low-dissipative nature of the high-order numerical schemes or from using a different LES approach (implicit/explicit), or a combination of the two. The present paper employs a numerical dissipation rate analysis technique due to Schranner et al. (Comput Fluids 114:84–97, 2015) to better understand the reasons for the high-order benefit seen previously on a complex LES test case related to gas-turbine combustors. It is established that a high(fifth)-order LES run provides better accuracy than its second-order FV counterpart at the same computational cost primarily because of lower numerical dissipation and the LES model dissipation has a secondary role to play. The numerical dissipation is found to contribute 60–90% of the total (numerical and LES model) dissipation.

Three levels of information processing in the brain

Information, the measure of order in a complex system, is the opposite of entropy, the measure of chaos and disorder. We can distinguish several levels at which information is processed in the brain. The first one is the level of serial molecular genetic processes, similar in some aspects to digital computations (DC). At the same time, higher cognitive activity is probably based on parallel neural network computations (NNC). The advantage of neural networks is their intrinsic ability to learn, adapting their parameters to specific tasks and to external data. However, there seems to be a third level of information processing as well, which involves subjective consciousness and its units, so called qualia. They are difficult to study experimentally, and the very fact of their existence is hard to explain within the framework of modern physical theory. Here I propose a way to consider consciousness as the extension of basic physical laws – namely, total entropy dissipation leading to a system simplification. At the level of subjective consciousness, the brain seems to convert information embodied by neural activity to a more simple and compact form, internally observed as qualia. Whereas physical implementations of both DC and NNC are essentially approximate and probabilistic, qualia-associated computations (QAC) make the brain capable of recognizing general laws and relationships. While elaborating a behavioral program, the conscious brain does not act blindly or gropingly but according to the very meaning of such general laws, which gives it an advantage compared to any artificial intelligence system.

Investigation of cooling control effect of fine water mist on lithium-ion battery thermal runaway

ABSTRACT The lithium-ion battery (LIB) thermal runaway (TR) has been a major safety problem, and effective countermeasure to suppress the TR becomes indispensable. Owing to the outstanding cooling capacity, the water mist presents efficient suppression effect on TR, but the comprehensive understanding on the cooling mechanisms remains unclear. In this work, the fine water mist (FWM) that is driven by the air flow has been applied to suppress the TR, and the cooling control processes under various thermal hazard conditions have been comprehensively analyzed. Results show that TR can be efficiently suppressed with the FWM applied before the critical temperature, which is identified as 252.5 ± 2.5°C. The average surface cooling rate increases from 1.04 to 1.22°Cs−1 with the increasing flow rate, and the total heat dissipation maintains approximately at 2.10 kJ, once the flow rate exceeds 0.2 mLs−1. It is identified that the most efficient cooling process can be obtained under the duration of 80 s. The influence of the flow rate and duration of the FWM on the cooling effect has been discussed to comprehensive reveal the control mechanism, and the excellent cooling control effect of the FWM flow has been verified.

Dissipation and energy propagation across scales in an active cytoskeletal material

Living systems are intrinsically nonequilibrium: They use metabolically derived chemical energy to power their emergent dynamics and self-organization. A crucial driver of these dynamics is the cellular cytoskeleton, a defining example of an active material where the energy injected by molecular motors cascades across length scales, allowing the material to break the constraints of thermodynamic equilibrium and display emergent nonequilibrium dynamics only possible due to the constant influx of energy. Notwithstanding recent experimental advances in the use of local probes to quantify entropy production and the breaking of detailed balance, little is known about the energetics of active materials or how energy propagates from the molecular to emergent length scales. Here, we use a recently developed picowatt calorimeter to experimentally measure the energetics of an active microtubule gel that displays emergent large-scale flows. We find that only approximately one-billionth of the system's total energy consumption contributes to these emergent flows. We develop a chemical kinetics model that quantitatively captures how the system's total thermal dissipation varies with ATP and microtubule concentrations but that breaks down at high motor concentration, signaling an interference between motors. Finally, we estimate how energy losses accumulate across scales. Taken together, these results highlight energetic efficiency as a key consideration for the engineering of active materials and are a powerful step toward developing a nonequilibrium thermodynamics of living systems.

A multiscale phase field fracture approach based on the non-affine microsphere model for rubber-like materials

Rubber-like materials have a broad scope of applications due to their unique properties like high stretchability and increased toughness. Hence, computational models for simulating their fracture behavior are paramount for designing them against failures. In this study, the phase field fracture approach is integrated with a multiscale polymer model for predicting the fracture behavior in elastomers. At the microscale, damaged polymer chains are modeled to be made up of a number of elastic chain segments pinned together. Using the phase field approach, the damage in the chains is represented using a continuous variable. Both the bond stretch internal energy and the entropic free energy of the chain are assumed to drive the damage, and the advantages of this assumption are expounded. A framework for utilizing the non-affine microsphere model for damaged systems is proposed by considering the minimization of a hypothetical undamaged free energy, ultimately connecting the chain stretch to the macroscale deformation gradient. At the macroscale, a thermodynamically consistent formulation is derived in which the total dissipation is assumed to be mainly due to the rupture of molecular bonds. Using a monolithic scheme, the proposed model is numerically implemented and the resulting three-dimensional simulation predictions are compared with existing experimental data. The capability of the model to qualitatively predict the propagation of complex crack paths and quantitatively estimate the overall fracture behavior is verified. Additionally, the effect of the length scale parameter on the predicted fracture behavior is studied for an inhomogeneous system.

Helios 2 observations of solar wind turbulence decay in the inner heliosphere

Aims. A linear scaling of the mixed third-order moment of the magnetohydrodynamic (MHD) fluctuations is used to estimate the energy transfer rate of the turbulent cascade in the expanding solar wind. Methods. In 1976, the Helios 2 spacecraft measured three samples of fast solar wind originating from the same coronal hole, at different distances from the Sun. Along with the adjacent slow solar wind streams, these intervals represent a unique database for studying the radial evolution of turbulence in samples of undisturbed solar wind. A set of direct numerical simulations of the MHD equations performed with the Lattice-Boltzmann code FLAME was also used for interpretation. Results. We show that the turbulence energy transfer rate decays approximately as a power law of the distance and that both the amplitude and decay law correspond to the observed radial temperature profile in the fast wind case. Results from MHD numerical simulations of decaying MHD turbulence show a similar trend for the total dissipation, suggesting an interpretation of the observed dynamics in terms of decaying turbulence and that multi-spacecraft studies of the solar wind radial evolution may help clarify the nature of the evolution of the turbulent fluctuations in the ecliptic solar wind.

Numerical study of the impact and aggregation characteristics of alumina droplets on a wall in the solid rocket motor

The impact and aggregation of multiple alumina droplets on the inner wall of the solid rocket motor may generate a larger rebound aggregated droplet or adhere to the wall to form a liquid film. The rebound and adhesion characteristics of the aggregated droplet are of great significance for slag deposition and two-phase flow prediction in the motor. In this paper, the VOF (Volume of fluid) method is used to study the impact and aggregation process of multiple alumina droplets on the wall. Detailed numerical verifications are carried out, including the impact and aggregation of moving droplets, the aggregation and rebound of stationary droplets and the impact process of a single alumina droplet on the wall. It is found that the aggregated droplet will rotate when two droplets aggregate under small droplet diameter ratio, which is caused by the asymmetry aggregation process. The oscillation process intensifies when three droplets impact and aggregate on the wall, as a result, the aggregated droplet is easier to adhere to the wall. The viscous dissipation in the aggregation of droplets is huge, and the total viscous dissipation energy accounts for about 50% of the total energy when the aggregated droplets rebound. The influence of droplet diameter on the V⁎ (rebound recovery coefficient) of the aggregated droplet and the rebound/adhesion results are dominated by the viscosity effect. While the influence of the parameters involving the initial spatial arrangement of droplets is dominated by the oscillation process, which will reduce the effective rebound kinetic energy, making a lower V⁎ and the aggregated droplet easier to adhere.