Melt Duration Research Articles

The distribution and evolution of supraglacial lakes on 79° N Glacier (north-eastern Greenland) and interannual climatic controls

Abstract. The Nioghalvfjerdsfjorden glacier (also known as the 79∘ North Glacier) drains approximately 8 % of the Greenland Ice Sheet. Supraglacial lakes (SGLs), or surface melt ponds, are a persistent summertime feature and are thought to drain rapidly to the base of the glacier and influence seasonal ice velocity. However, seasonal development and spatial distribution of SGLs in the north-east of Greenland are poorly understood, leaving a substantial error in the estimate of meltwater and its impacts on ice velocity. Using results from an automated detection of melt ponds, atmospheric and surface mass balance modelling, and reanalysis products, we investigate the role of specific climatic conditions in melt onset, extent, and duration from 2016 to 2019. The summers of 2016 and 2019 were characterised by above-average air temperatures, particularly in June, as well as a number of rainfall events, which led to extensive melt ponds to elevations up to 1600 m. Conversely, 2018 was particularly cold, with a large accumulated snowpack, which limited the development of lakes to altitudes less than 800 m. There is evidence of inland expansion and increases in the total area of lakes compared to the early 2000s, as projected by future global warming scenarios.

Experimental investigation on the melting and solidification performance enhancement of a fractal latent heat storage unit

This work designs a fractal latent heat storage (LHS) unit with tree-shaped fins for enhancing heat exchange efficiency. The melting/solidification processes inside a fractal LHS unit are experimentally studied by visualization observation, focusing on the role of inclination angles. Comparative studies on fractal LHS and traditional LHS units are conducted by assessing the temperature response, phase change behavior, liquid fraction variation, and thermal storage/release performance. The experimental results indicate that the inclination angle presents a more significant impact on melting processes than solidification processes, especially for thermal characteristics in the axial direction. Variations in the onset and duration of natural convection determine the main difference in the melting/solidification mechanism of fractal LHS units. Large inclination angle is not conducive to convection development, thus prolonging the late conduction-dominated stage and diminishing the overall thermal performance. Therefore, the thermal characteristics of fractal LHS units are less affected by orientations than traditional LHS units. Moreover, the overall thermal performance of fractal LHS units is more superior to traditional LHS units irrespective of orientations. Particularly, the vertical fractal LHS unit has a maximum reduction of 52.6% in the complete melting duration, and the heat storage/release rate of horizontal fractal LHS units augments by 94.7% and 101.5% when compared with traditional LHS units.

Trends in Flowering Phenology of Herbaceous Plants and Its Response to Precipitation and Snow Cover on the Qinghai—Tibetan Plateau from 1983 to 2017

Based on limited controlled experiments, both advanced and delayed shifts in flowering phenology induced by precipitation and snow cover have been reported on the Qinghai–Tibetan Plateau (QTP). To clarify the impact of precipitation and snow cover on flowering phenology, we conducted a comprehensive statistical analysis of the temporal change in flowering phenology and its responses to precipitation and snow cover changes using regression models built on the largest collection of ground phenological observation data on the QTP. We found that first flowering date (FFD) for the early-flowering time series significantly advanced at the rate of −0.371 ± 0.149 days/year (p < 0.001), whereas FFD mid-to-late-flowering time series showed no trend at the rate of 0.158 ± 0.193 days/year (p = 0.108). Cumulative pre-season precipitation regressed with FFD positively for early-flowering time series, with the explained variation ranging from 11.7 to 49.4% over different pre-season periods. The negative impact of precipitation on flowering phenology is unexpected, because an increase in precipitation should not hamper plant growth in the semi-arid and arid environments on the QTP. However, precipitation was found to be inversely correlated with temperature. Thus, it is likely that temperature, and not precipitation, regulated flowering phenology over the study period. No relationship was found between FFD and snow-cover melt date or duration. This result indicated that snow cover may not affect flowering phenology significantly, which may be because plant flowering time was much later than the snow-cover melt date on the QTP. These findings contrast the results of controlled experiments on the QTP, which showed that precipitation regulated flowering phenology, and with other studies that showed that snow-cover melting time determined flowering dates of early-flowering species in high latitude and Arctic zones in Europe and North America, where the low-temperature environment is similar to the QTP. These findings can improve flowering phenology models, assist in the prediction of phenological responses of herbaceous plants to climate change, and forecast changes in the structure and function of the grassland ecosystem on the QTP.

One-pot synthesis of MoS2 nanoflowers for thermal energy storage applications

In this study, flower-like MoS2 nanospheres were synthesized via a facile hydrothermal route. The morphological and phase analysis confirmed the formation of polycrystalline MoS2 nanoflowers assembled by lamellar nanosheets. A novel shape-stabilized phase change material was fabricated by imprisoning different concentrations of MoS2 into myristic acid. It was observed from the experimental results that the duration of melting and cooling rates for PCM of 0.25 wt%, 0.5 wt%, 0.75 wt%, 1 wt%, 1.25 wt% increased as compared to pristine counterparts. 1 wt% had the highest heat transfer rate, with a value of 9.4% and 52.81% for melting and cooling, respectively. The result from analytical technique showed there was no chemical reaction between MoS2 and myristic acid even after multiple cycles. Since this unique MoS2 based composite has indicated good thermal reliability for latent-heat storage, and release, this composite can be considered as an appropriate PCM for thermal energy storage applications.

Experimental study on melting enhancement of phase change material in a vertical cylindrical latent heat storage using a short concentric helical heat transfer tube

Phase change materials (PCM) are preferred in thermal energy storage (TES) for their considerable heat storage capability even though it lacks thermal conductivity. The solid PCM settling at the bottom in an upright cylindrical TES unit with a helical heat transfer tube (HTT) takes a longer melting duration. Adding a short concentric helical HTT at the bottom-center is investigated to melt the solid PCM. Paraffin wax with a melting temperature of 60 °C has opted as PCM. Water is the heat transfer fluid (HTF) that passes through the outer tube circumferentially downward and then through the short inner HTT upward at 70, 75, 80 °C and 20, 25, and 30 LPH. The PCM melting is ensured through visual and spatial temperature measurements. The modification of HTT decreased the melting duration by 36.84% compared with an unmodified HTT. The fluid flow rate of 20 LPH and inlet temperature of 80 °C produced complete PCM melting in 120 min: the maximum energy efficiency of 39.32%: the exergy efficiency of 32.43%. This study helpful to design HTT for various solar applications requiring thermal storage.

Urbanization and Winter Precipitation: A Case Study Analysis of Land Surface Sensitivity

Urban modification of precipitation regimes is well documented in the urban climate literature. Studies investigating urbanization and non-convective precipitation, specifically winter precipitation, are limited. The theoretical framework here argues that the collective influence of urbanization extends beyond traditional city limits and the surrounding rural areas and can impact regional climate in non-adjacent cities. This paper utilizes the weather research and forecasting model (WRF-ARW) to simulate a cold-season synoptic system over the Northeastern United States over a variety of urban land surface scenarios. This case study centers on the potential boundary layer urban heat island effect on the lower troposphere and its ability to impact winter precipitation type at the local to regional scales. Results show a significant reduction in temperatures near the modified surface and subtle reductions over adjacent urban areas. When surface wind speeds are less than 5 ms−1, the boundary layer heat island increases air temperatures on the order of 3–4 °C at altitudes up to 925 mb. When combined with encroaching warm air near 850 mb during transitional precipitation events, the boundary layer heat island increases the thickness of the melting layer and consequently exposes falling hydrometeors to longer melting duration and phase change. Model simulations also show regional connections through remote temperature and relative humidity changes in urban areas removed from reforested areas.

Ice behaviors and heat transfer characteristics during the isothermal production process of methane hydrate reservoirs by depressurization

Methane hydrate is a new environmentally friendly alternative energy source in the future. During its conventional production process by depressurization, ice behaviors and heat transfer characteristics are two key factors affecting the hydrate dissociation rate. In this study, different reservoir temperatures (276.2, 277.2 and 278.2 K) and production pressures (2.3, 2.6 and 3.1 MPa) were employed to investigate the methane hydrate production process. Icing, which increases the reservoir temperature and significantly promotes the dissociation of hydrates instantaneously, is generally observed under 2.3 MPa production pressure due to the large temperature decrease by depressurization. Higher initial temperatures decrease both the formation amount and melting duration of ice, and higher production pressures can avoid the formation of ice by decreasing the temperature drop. In addition, both ice melting and hydrate dissociation are isothermal when limited by the external heat supply. During the hundreds of minutes of ice melting process, the area with ice is estimated to shrink gradually. Similarly, the dissociation rate of hydrates is controlled by the heat supply and even becomes constant when the driving force is small enough (high production pressure). The results of this study are significant for the rate control of methane hydrate exploitation.

Time-resolved in-situ temperature measurement and analysis for continuous-wave laser sintering of carbon nanotube – Metal composites on a polymer substrate

Previous research work shows that metal nanocomposite thin films fabricated by laser sintering of mixtures of metal nanoparticles (NPs) and carbon nanotubes (CNTs) on a polymer substrate have a great potential to help enhance reliability and durability of metal components in flexible electronic devices. To gain a good relevant fundamental understanding, it is important to know the material thermal history during laser sintering. However, an in-situ temperature measurement has been rarely reported in a paper in the literature for laser sintering of metal NP-CNT mixture thin films on a polymer substrate. Such temperature measurements are reported in this paper, which are performed using a two-color pyrometry system set up by the authors to overcome related technical challenges such as high spatial and temporal resolution requirements. The measurement method is non-contact, and by measuring thermal radiation in two wavelength ranges it does not require the value of the target surface emissivity. The electrical resistivities of composite material sintered with different laser scanning speeds are also measured. Under the conditions studied, it has been found that as the laser scanning speed increases significantly, the average melted material temperature in the measurement spot only slightly decreases, but the melting duration drops significantly. The average electrical resistivity of sintered composite material first decreases and then increases with the laser scanning speed. The measured material surface temperatures for laser sintering of CNT and silver NP mixtures are similar to those for laser sintering of silver NPs with the same laser scanning speed.

Role of graphitized mesoporous carbon on solidification and melting characteristics of water for cool thermal storage

Cool thermal energy storage systems (CTES) using phase change materials (PCM) are paramount in the energy management of buildings. This work aims to investigate the role of graphitized mesoporous carbon (GMC) on the thermal storage behavior of water based nanofluid PCM (NFPCM) in a spherical capsule. The NFPCMs exhibit a lower contact angle, indicating a reduction in the nucleation energy barrier. Thermal conductivity of NFPCM shows an enhancement of 36% with the presence of graphitized walls and isotropic nature of GMC. Temperature–time history method is used to evaluate the latent heat of fusion for the NFPCMs and the results are compared with differential scanning calorimetry measurements. Addition of GMC shortens the solidification duration by 6% and reduces the subcooling of NFPCM compared to base PCM. The charging results of NFPCMs demonstrate a cool energy storage of 96% in accelerated mode. The melting rate of NFPCM is expedited at a minimal GMC concentration and melting duration prolongs with further GMC addition. In conclusion, the proposed NFPCMs exhibiting a lower subcooling, improved nucleation behavior and accelerated mode of charging shows great potential for CTES applications.

Timescales of Partial Melting and Melt Crystallization in the Eastern Himalayan Orogen: Insights From Zircon Petrochronology

AbstractRevealing the timescales of metamorphic and anatectic processes is central to our understanding of tectonic evolution of collisional orogens. High‐temperature migmatites and leucogranites are well exposed in the Himalayan orogenic core, making it an ideal region to study the timing and duration of partial melting and melt crystallization of the orogen. Here, we report an integrated and comprehensive data set of petrography, U‐Pb age, and trace element data for zircon from a pelitic granulite and associated leucosomes of the Greater Himalayan Sequence (GHS) in the Yadong area, eastern Himalaya. Zircon grains with complex internal structure retain variable ages ranging from 32 Ma to 13 Ma that correlate systematically with changes in the concentrations of Y, Th, U, Hf, Nb, Ta, and HREE, and ratios of Th/U, Eu/Eu*, and Nb/Ta. Combined with petrologic analysis, we conclude that the granulite witnessed high‐temperature metamorphism, melting, and melt crystallization over ∼20 Myr. Prograde, simultaneous increases in pressure and temperature and associated dehydration melting began at least by ∼32 Ma and lasted until ∼24 Ma. Subsequent quasi‐isothermal decompression‐melting occurred between ∼22 and 19 Ma, and late melt crystallization spanned ∼19 to 13 Ma. Large volumes of melt generated during prograde metamorphism could have triggered exhumation of GHS rocks, increasing melt fraction through a positive feedback between exhumation and melting. More comprehensive analysis of different rock types led to more complete and different interpretations for the timing of exhumation and melt crystallization in the Yadong‐Sikkim region and might enable alternate interpretations elsewhere in the Himalayas.

Thermal management of single and multiple PCMs based heat sinks for electronics cooling

The present study focuses on passive thermal management of electronic devices using heat sinks embedded with single or multiple phase change materials (PCMs). RT58, RT44 and n-Eicosane are used as PCMs, while aluminium fins are used as thermal conductivity enhancer (TCE). Single PCM cases are investigated independently while multiple PCMs pairs are studied through their filling in alternate enclosures separately. Three constant heat fluxes of 1.5, 2.5 and 3.5 kW/m2 are applied to the heat sinks to investigate PCMs’ thermal performance. The numerical model is validated against available experimental results where an acceptable 2.9% difference in the transient temperature is achieved. High values of Nusselt number were discovered at the beginning of melting and the end of solidification stages. The RT44 shows the lowest peak temperature and longest melting duration among single PCM cases, due to its high latent heat of fusion. When n-Eicosane and RT44 are paired in a heat sink, the best overall thermal performance is achieved where its operational time is increased by 3.3–12% comparing to single n-Eicosane or RT44. The results show that the multiple PCMs pair of n-Eicosane/RT44 is feasible for high critical temperature devices due to its longer operating time and also lowest average transient temperature.

The 32-year record-high surface melt in 2019/2020 on the northern George VI Ice Shelf, Antarctic Peninsula

Abstract. In the 2019/2020 austral summer, the surface melt duration and extent on the northern George VI Ice Shelf (GVIIS) was exceptional compared to the 31 previous summers of distinctly lower melt. This finding is based on analysis of near-continuous 41-year satellite microwave radiometer and scatterometer data, which are sensitive to meltwater on the ice shelf surface and in the near-surface snow. Using optical satellite imagery from Landsat 8 (2013 to 2020) and Sentinel-2 (2017 to 2020), record volumes of surface meltwater ponding were also observed on the northern GVIIS in 2019/2020, with 23 % of the surface area covered by 0.62 km3 of ponded meltwater on 19 January. These exceptional melt and surface ponding conditions in 2019/2020 were driven by sustained air temperatures ≥0 ∘C for anomalously long periods (55 to 90 h) from late November onwards, which limited meltwater refreezing. The sustained warm periods were likely driven by warm, low-speed (≤7.5 m s−1) northwesterly and northeasterly winds and not by foehn wind conditions, which were only present for 9 h total in the 2019/2020 melt season. Increased surface ponding on ice shelves may threaten their stability through increased potential for hydrofracture initiation; a risk that may increase due to firn air content depletion in response to near-surface melting.

Bi-objective Optimization of Maraging Steel Produced by Vacuum Induction Melting Using Evolutionary Algorithms

Maraging steel is a special alloy exhibiting excellent combination of ultra-high strength with considerable ductility. Thus, such steel become significant worldwide for strategic sectors (like nuclear, aerospace and defence) where stringent quality standards with respect to chemistry and properties is compulsory. Manufacturing of these steel is extremely difficult, and vacuum induction melting (VIM) furnace plays most significant part as a primary melting unit. There are a large number of processing parameters to manufacture these special alloys and on top of that, these type of vacuum furnaces are connected with various valves, motors, sensors along with safety systems, which lead to involvement of additional interdependent process variables. Accordingly, building logical agent is often difficult because the developer requires possessing the complete and intricate knowledge of all the agents, which is viable only for deterministic environment. In case of nonlinear condition, the data generation and collection in digital form is a very useful resource of valuable information for meaningful process optimization-related investigation by developing intelligent model from databases. In this perspective, data-driven optimization using evolutionary algorithms is effective tool in order to optimize parameters related to melting time of manufacturing maraging steel through critical analysis of the data. Data of 130 heats collected from VIM 6.5 Tonne furnace and the considered parameters are weight of carbon added, leak rate of system, complete meltdown time, carbon–oxygen–nitrogen pct in opening sample, carbon–oxygen–nitrogen pct in final stages of melting, refining time, leak rate during melting, tapping temperature, melt duration and tap to start time between previous and present melting and lining life. Out of aforementioned fifteen parameters, minimization of refining time and melt duration is the objectives of the present investigation. Evolutionary neural network has been used as a primary optimization algorithm for present investigation which is coupled with predator–prey genetic algorithm (PPGA). Optimization using PPGA has been achieved successfully and obtained the trade-off between refining time and melt duration. The analyses of all input parameters reveal that the complete meltdown time and carbon addition at start are the two main parameters which can affect the melting and refining time greatly. Putting extra care on these two parameters will greatly affect the melting time of maraging steel in VIM furnace.

Thermal analysis of Fe2O3 - myristic acid nanocomposite for latent heat storage

Phase change materials (PCM) are commonly utilized materials in latent heat energy storage (LHES) systems. In the present study, Fe2O3 was incorporated into myristic acid. The composites were prepared by melting and mixing method. The acids dispersed with Fe2O3 were prepared to enhance the thermal properties of the PCM mixtures and heat transfer at various nanoparticle loadings of 1 wt%, 2 wt%, 3 wt%, and 4 wt% were investigated. It was observed from the experimental results that the duration of melting and cooling rates for PCM composites increased in all nano compositions with respect to the pure myristic acid. Fourier transform infrared spectrum confirmed higher chemical stability of the nanoenhanced phase change material.

A three-dimensional computational analysis of ellipsoidal radiator with phase change

PurposeThe purpose of this paper is to solve the problem of a three-dimensional computational analysis for an elliptic-shaped cavity in a pipe under constant temperature.Design/methodology/approachThe three-dimensional computational solution of governing equations was performed by using finite volume method with different temperature difference.FindingsThe parafin wax was chosen as a phase change material (PCM), and melting fraction, streamlines and isotherms are formed for different time step. It is found that position B give better results than that of position A, and temperature difference effects the duration of melting of PCM.Originality/valueThe three-dimensional analysis of melting in an ellipsoidal pipe with inner pipe with higher temperature is the main originality of this work.

Thermal performance enhancement of eutectic PCM laden with functionalised graphene nanoplatelets for an efficient solar absorption cooling storage system

The present work investigates the thermal enhancement of a binary eutectic phase change material (PCM) (150–200 °C), laden with different concentrations of COOH-functionalized Graphene nanoplatelets (f-GNP) for a multi-effect solar cooling thermal storage system. The novel nano-composite is prepared by varying the weight concentration of f-GNP from 1% to 5% in a pristine eutectic salt of LiNO3-KCl (50:50) using the standard nano synthesis protocol. The microstructure, dispersion uniformity are evaluated using scanning electron microscope (SEM) and thermophysical properties of the nano-composite are characterized using dynamic Differential scanning calorimetry (DSC). The thermal conductivity enhancement due to the doping of f-GNP is studied through a series of experimental trials conducted with Laser flash analysis (LFA). The obtained data is plotted and compared with a more robust theoretical thermal conductivity model. It is found that thermal conductivity rises by 104% with f-GNP dispersions, which reflects the improved thermal performance of the storage system. The specific heats of the solid and liquid phase show an increase of 80% & 38% respectively at f-GNP concentration of 5%. Finally, the effect of doping f-GNP on the conjugate heat transfer inside the PCM and fluid flow of HTF is investigated in a vertical shell and tube type storage system, suitable for the double effect solar cooling system. The f-GNP dispersions accelerate the heat storage process with a maximum decrease of 17.3% in the total melt duration. In addition, the role of increased viscosity on the natural convection is simultaneously studied with the increased thermal conduction due to nanoplatelets dispersions.

The 2020 Larsen C Ice Shelf surface melt is a 40-year record high

Abstract. Along with record-breaking summer air temperatures at an Antarctic Peninsula meteorological station in February 2020, the Larsen C ice shelf experienced an exceptionally long and extensive 2019/2020 melt season. We use a 40-year time series of passive and scatterometer satellite microwave data, which are sensitive to the presence of liquid water in the snow pack, to reveal that the extent and duration of melt observed on the ice shelf in the austral summer of 2019/2020 was the greatest on record. We find that unusual perturbations to Southern Hemisphere modes of atmospheric flow, including a persistently positive Indian Ocean Dipole in the spring and a very rare Southern Hemisphere sudden stratospheric warming in September 2019, preceded the exceptionally warm Antarctic Peninsula summer. It is likely that teleconnections between the tropics and southern high latitudes were able to bring sufficient heat via the atmosphere and ocean to the Antarctic Peninsula to drive the extreme Larsen C Ice Shelf melt. The record-breaking melt of 2019/2020 brought to an end the trend of decreasing melt that had begun in 1999/2000, will reinitiate earlier thinning of the ice shelf by depletion of the firn air content, and probably affected a much greater region than Larsen C Ice Shelf.

Effect of conical coiled heat transfer fluid tube on charging of phase-change material in a vertical shell and coil type cylindrical thermal energy storage

ABSTRACT Effective thermal energy storage is essential to overcome the intermittent availability of solar energy. A small cylindrical thermal energy storage unit is investigated to provide heat during the early morning for domestic hot water using flat plate solar water heaters. A helically coiled heat transfer tube (HTF) in cylindrical thermal storage is investigated on charging phase-change material (PCM). An acrylic cylindrical container is used to hold the PCM. HTF tube is made up of copper helical coil with and without a conical section at the bottom of the loop. The heat transfer tube at the bottom is formed into a small conical shape at the helical coil’s center. The selected PCM is paraffin wax with a melting temperature of about 60°C. The HTF temperature is maintained at 75°C at a flow rate of 0.5 kg/min to charge the PCM of 1 kg mass. Part of solid PCM at the container’s bottom was observed with a longer duration to melt entirely without a conical section of the HTF tube. The irregular temperature distribution was also observed in PCM, mainly along the vertical direction. Thus, the complete melting was achieved by a conical coiled heat transfer tube at the container’s bottom. The conical coil length of the HTF tube increased the overall length by 10%. The PCMs melting duration with a conical tube at the bottom reduced significantly by 16% and enhanced average storage effectiveness by 13.06% compared to the HTF tube without the conical coil. Abbrevations: HTF: Heat transfer fluid; LHS: Latent heat storage; PCM: Phase-change material; TES: Thermal energy storage

Linking oral processing behavior to bolus properties and dynamic sensory perception of processed cheeses with bell pepper pieces

The addition of food particles to food matrices is a convenient approach that allows to steer oral behavior, sensory perception and satiation. The aim of this study was to determine the influence of physical-chemical properties of heterogenous foods on oral processing behavior, bolus properties and dynamic sensory perception. Bell pepper gel pieces varying in fracture stress and concentration were added to processed cream cheese matrices differing in texture. Addition of bell pepper gel pieces to processed cheeses increased consumption time, decreased eating rate and led to harder and less adhesive bolus with more saliva incorporated. Addition of bell pepper gel pieces to processed cheeses decreased dominance rate and duration of creaminess, smoothness, melting and dairy flavor and increased graininess and bell pepper flavor. Increasing fracture stress of bell pepper gel pieces from 100 to 300 kPa resulted in longer consumption time and lower eating rate. For hard/non-adhesive processed cheese matrices increasing gel pieces fracture stress lead to a boli with larger particles and more saliva. These changes were accompanied by decreased dominance perception of creaminess and bell pepper flavor and increased dominance of graininess. Increasing the concentration of bell pepper gel pieces from 15 to 30% did not affect oral behavior but led to the formation of harder and less adhesive bolus with larger particles and less saliva that were perceived with reduced dominance of creaminess, meltiness and dairy flavor while dominance of graininess and bell pepper flavor increased. Changing the texture of the cheese matrix from soft/adhesive to hard/non-adhesive decreased consumption time, increased eating rate, did not influence bolus properties and decreased dominance rate of creaminess, smoothness and melting sensations. Number of chews and total consumption time were positively correlated with saliva content of the bolus, number of bolus particles, bolus hardness, dominance of firmness, chewiness and graininess. We conclude that the modification of physical-chemical properties of processed cheeses and embedded bell pepper gel pieces can be a strategy to steer oral behavior and bolus properties which consequently determine dynamic sensory perception.

Melting heat transfer enhancement of a horizontal latent heat storage unit by fern-fractal fins

The latent heat storage (LHS) technique is of crucial importance in chemical energy engineering. Inspired by multi-bifurcated fern leaves, a mimic fern-fractal fin is designed to improve the thermal energy charging efficiency. This paper develops a transient melting model of a rectangular LHS unit using fern-fractal fins, and their melting behaviors are compared with the conventional fins. Besides, a parametric optimization of fern-fractal fins is conducted for maximizing the thermal efficiency based on the response surface method (RSM). The results indicate that the temperature uniformity is more superior and the melting duration is shorter for the fern-fractal LHS unit when compared with the conventional one. Interestingly, the fern-fractal LHS device presents a slower heat storage rate during the initial conduction-dominated and early convection-dominated melting stages, while a prominent melting enhancement is achieved during the later melting stage. The shortest melting time is obtained based on the RSM technique when a fern-fractal fin with length ratio α = 0.94 and branch angle θ = 54.7° is utilized. Compared with a conventional fin, the averaged heat storage rate increases by 88.3%, and the total melting time is declined by 40.3% for an optimized fern-fractal fin.