Triplex Tube Research Articles

A critical assessment of nanoparticles enhanced phase change materials (NePCMs) for latent heat energy storage applications

Phase change material (PCM) laden with nanoparticles has been testified as a notable contender to increase the effectiveness of latent heat thermal energy storage (TES) units during charging and discharging modes. In this study, a numerical model is developed and implemented based on the coupling between an advanced two-phase model for the nanoparticles-enhanced PCM (NePCM) and the enthalpy-porosity formulation for the transient behavior of the phase change. Therefore, a porosity source term is added to the nanoparticles transport equation to account for the particles' frozen state in regions occupied by solid PCM. This two-phase model includes three main nanoparticles’ slip mechanisms: Brownian diffusion, thermophoresis diffusion, and sedimentation. A two-dimensional model of a triplex tube heat exchanger is considered and different charging and discharging configurations are analyzed. Compared to pure PCM, results show a substantial heat transfer enhancement during the charging and discharging cycle in which a homogeneous distribution of nanoparticles is considered as the initial condition. For this case, the two-phase model predictions are superior to the ones obtained with the classical single-phase model. In the case of multi-cycle charging and discharging, a significant deterioration of the heat transfer rate is observed using the two-phase model while such assessment is senseless using the single-phase mixture model due to the physical assumptions upon which this model is formulated. The two-phase model results reveal that, for a NePCM with high nanoparticles concentration (> 1%), the melting performance during the second charging cycle is reduced by 50% compared to the first one. This performance degradation is attributed to a noteworthy non-homogeneous distribution of the nanoparticles at the beginning of the second charging cycle. The dominant nanoparticles migration mechanism, in this scenario, is the one resulting from sedimentation effects.

Heat Transfer Augmentation Using Duplex and Triplex Tube Phase Change Material (PCM) Heat Exchanger Configurations

The significance of latent heat thermal energy storage is more substantial when compared to sensible energy storage due to its higher energy storage capability. In this paper, heat transfer enhancement techniques for melting (charging) and solidification (discharging) by using external fins and internal–external fins for a phase change material (PCM) in duplex and triplex tube heat exchangers (DTHX and TTHX) are investigated numerically. A two-dimensional analysis is carried out using ANSYS Fluent for various configurations. Moreover, the effect of different critical parameters, number of fins, fin length, fin thickness, and the heat exchanger tube material are evaluated in terms of the total time of complete phase change of the PCM. Four cases are investigated; cases 1 and 2 are based upon a DTHX while cases 3 and 4 are TTHXs. By considering case 1 as a reference case, it is found that case 2 and case 3 reduce the total melting time by 48.76% and 90.12%, respectively. Case 4 achieves the shortest time for complete melting of the PCM, and the total melting time is decreased by 92%. Solidification behaviour for all four cases is also investigated. The novel configurations increase (doubled) the supply of heat transfer fluid (HTF) while at the same time significantly enhance the melting/solidification characteristics for all the cases without disrupting the convectional currents during phase change of the PCM. Tube materials with different thermophysical properties are also investigated with the heat transfer rate and melting time significantly improved with a high thermal diffusivity material. Moreover, the heat transfer is found to increase with fin length and fin thickness.

3D Numerical Analysis of a Phase Change Material Solidification Process Applied to a Latent Thermal Energy Storage System

The techniques for releasing thermal energy accumulated in periods of high availability to meet the demand in periods of low energy supply contribute to the continuity of the cycles involved in thermodynamic processes. In this context, phase change materials are capable of absorbing and releasing large amounts of energy in relatively short periods of time and under specific operating conditions. However, phase change materials have low thermal conductivity and need to be coupled with high-thermal-conductivity materials so that the heat flux can be intensified and the energy absorption and release times can be controlled. This work aims to numerically study the solidification process of a phase change material inserted into a triplex tube heat exchanger with finned copper walls to intensify the thermal exchange between the phase change material and the cooling heat transfer fluid, water, that will receive the energy accumulated in the material. This work proposes the 3D numerical modeling of the triplex tube heat exchanger with finned walls and meets the need for numerical models that allow for the analysis of the full geometry of the latent heat thermal energy storage system and the thermal and fluid dynamic phenomena that are influenced by this geometry. Results of the temperature, liquid fractions and velocity fields during phase transformations are presented, analyzed and validated with experimental data, presenting average errors of below 5%. The total material discharge time was approximately 168 min, necessary for the complete solidification of the phase change material, with water injected into the triplex tube heat exchanger at a flow rate of 8.3 L/min and a temperature of 68 °C. The solidification process occurred more slowly in the same direction as the length of the triplex tube heat exchanger, and from 80% of the material in the solid state, the difference between the solidification time for z = 0 and z = 480 mm was 30 min. The fluid dynamic conditions developed in the latent heat thermal energy storage system promoted a maximum negative heat flux of −6423 w/m2 to the annular internal surface and −742 w/m2 to the annular external surface, representing a heat removal process nine times less intense on the external surface. The total energy released to the cooling heat transfer fluid was 239.56 kJ/kg.

Experimental Approach for Enhancing the Natural Convection Heat Transfer by Nanofluid in a Porous Heat Exchanger Unit

Natural convection heat transfer is a significant component in the energy transfer mechanism and plays an essential role in a wide range of scientific and industrial technologies. This research seeks to enhance the energy transfer by nanofluid, which is compatible with some applications, such as heat exchanger thermal energy storage (HXTES). For this purpose, a triplex tube heat exchanger (TTHX) is designed to receive the hot and cold flow by two pumps from two thermal baths, respectively. Samples of the Copper (Cu) nanoparticles were then carefully selected in a volume concentration range of 0.05 ≤ ∅ ≤ 0.5 to promote the thermal conductivity of the base fluid, which consists of 55% water and 35% ethylene glycol (EG), and to form nanofluid. On the other side, the effect of the porous medium of glass spheres inside a TTHX is considered. Experimentally, and after preparing the nanofluid, temperature readings of six various thermocouples locations have been investigated. The effects of Cu volume concentrations under different temperatures of 20 °C, 30 °C and 50 °C on nanofluid heat transfer are evaluated, respectively. One more result: the yields in the heat transfer coefficient of the hot tube were higher compared to those of the cold tube under Reynolds number (Re) between 200 and 7000. The efficiency of transition and turbulent flow through TTHX is clearly appointed. Overall, these findings support the supposition that the heat transfer enhancement is optimized by 0.05% nanoparticle volume concentration due to increasing thermal conductivity and fluid movement effectiveness. Ultimately, a natural progression of this work is to analyze more convective form using controlled trial applications, such as solar collectors.

Thermal Energy Storage with PCMs in Shell-and-Tube Units: A Review

The paper presents a survey of the experimental and numerical studies of shell-and-tube systems in which phase change material (PCM) is used. Due to the multitude of design solutions for shell-and-tube systems, the emphasis is placed on double-tube (DT), triplex-tube (TT), and multi-tube (MT) units. Additionally, only single-pass systems are considered. Particular attention is paid to the method of heat transfer intensification. The analysis of the research results begins with the classification of each of the three mentioned systems. The systems are divided according to the angle of inclination, the method of heat transfer enhancement (HTE), the flow direction of heat transfer fluid (HTF), and the arrangement of tubes in the bundle. Moreover, the simplified schemes of the particular research cases are proposed. Then, the works on each of the mentioned systems, i.e., DT, TT, and MT, are discussed chronologically. Finally, in the corresponding tables, details of the discussed cases are presented, such as geometric dimensions, and the type of PCM or HTF used. A novelty in the present work is the precise classification of PCM TESUs as DT, TTH, and MTH. In the literature, there is a lot of discretion in this regard. Second, the methods of heat transfer intensification in the presented PCM TESUs are listed and discussed. Third, unified schemes of design solutions for the discussed PCM TESUs are proposed. The review shows that development directions for shell-and-tube TESUs include systems with high conductivity fins of different shapes, heights, and spacing, several PCMs, and modified shells.

Uticaj disperzije hibridnih nanočestica Al2O3/CuO na proces topljenja PCM-a u tripleks cevi za skladištenje toplote

This research conducts an experimental and theoretical investigation of the melting characteristics of a phase change material in a triplex tube heat storage. A three-dimensional model is simulated numerically employing Ansys Fluent software. The enthalpy porosity method is chosen for solving the phase transition of paraffin wax. A blend of equal-volume CuO and Al2O3 hybrid nano-additives was used as conductive material to enhance heat transfer in PCM, which can be considered the originality of this study. At first, the differential scanning calorimeter (DSC) analysis was performed to determine the paraffin thermo-physical properties. Various volume concentrations of 0.4%, 0.8%, 1.6%, and 3.2% were dispersed in paraffin. Besides that, the experiment was performed under different mass flow and inlet fluid temperatures to study the effect of these two parameters on the phase transition rate. The outcomes indicate that adding an Al2O3/CuO hybrid nanoparticle of volume fraction of 0.4-3.2% causes a reduction in total charging time between 10% and 19%. The result also showed that the theoretical efficiency boosts from 61.7% to 84.8% as heat transfer fluid (HTF) inlet temperature increases from 62 °C to 78 °C.

Performance of energy storage unit equipped with vase-shaped fins including nanoparticle enhanced paraffin

Inventing new fins with vase-shaped to incorporate in the storage enclosure has been suggested in current work to decline the energy consumption. Combination of heat storage with shape of triplex tube with parabolic solar unit makes the efficiency to intensify. The properties of paraffin were intensified with dispersing SiO2 nanoparticles. Different proposed models contain various ranges of fraction of nano-powders and three arrangements of vase-shaped fins. Finite volume method with involvement of both conduction and convection modes was applied to scrutinize the system numerically and its accuracy was assessed by comparing the outputs with previous article. The best arrangement for the target of maximum efficiency and minimum time of charging was the third style of fins (Diameter ratio (DR) = 1) in which fins are attached to both hot surfaces and with inclusion of nano-powders, it takes 20.91 min to achieve full melting. With changing the features of paraffin due to dispersing nano-powders, the melting time reduces around 3.83 % when DR = 1. Moreover, with the change of style of fins from DR = 0.6 to DR = 1, the melting time drops around 6.06 %.

Melting expedition in horizontal triplex tube heat exchangers via radial and combined radial-axial fins

The effects of using radial fins on the melting of a Phase-Change Material (PCM) inside a horizontal Triplex Tube Heat Exchanger (TTHX) are investigated in this study. To this aim, several configurations of radial fins and their combination with conventional axial fins are considered. First, the melting in a TTHX equipped with axial fins is simulated to assess the validity of the solver. The numerical predictions agree well with the experimental data. Next, the melting process in a TTHX equipped with different configurations of radial fins is simulated to compare their thermal performance with that of the longitudinal fins. Effects of multiple parameters are investigated, such as the fin radii and number, replacing full circle fins with arc fins, and axial distribution of the fins. The results indicate that inserting arc fins in the lower section of the PCM enclosure improves the thermal performance significantly. This leads to an 18 % reduction in melting time when their axial spacing is non-uniform. Also, combined radial-axial configurations, considered in the present research for the first time, greatly accelerate the melting if the axial fins are located on the inlet side of the PCM enclosure and the radial fins are located on the other half.

Performance enhancement of triplex tube latent heat storage using fins, metal foam and nanoparticles

The inherent low thermal conductivity of latent heat storage materials hinders its effective use due to quite long charging/discharging process. Heat transfer enhancement techniques are promising solutions to overcome this major drawback. In this study, the effect of combining heat transfer techniques including fins of different arrangements, fins-nanoparticles, and fins-metal foam is numerically examined and compared for latent thermal energy storage in a triplex tube. Two fin configurations are examined uniform as well as non-uniform. The predictions of the numerical model are validated by comparisons with experimental data available in the literature. The transient liquid fraction, temperature distribution, and interface position are analyzed for the considered cases. Results show that the non-uniform fin arrangement contributes to improving the thermal energy storage. The non-uniform fin distribution expedites the melting rate by 56.45%. Furthermore, it is shown that the combination of fins-metal foam outperforms the fins-nanoparticles configuration. The time needed for full charging and discharging reduces with fin-metal foam by up to 80.12% and 90.04%, respectively, depending on the fin arrangement. The proposed storage model and results are useful for designing efficient thermal energy storage units.

Investigative Study of Solidification and Melting of Stearic Acid in Triplex Pipe with Perforated Fin Surface

The energy storage capacity of latent heat thermal energy storage systems is high therefore these systems are efficient among all other thermal heat storage. This study experimentally investigates the charging and solidification of stearic acid (C18H36O2) in the finned triplex pipe heat exchanger with holes on the fin surface. The melting and discharging of stearic acid are carried out at steady inlet heat transfer fluid (HTF) i.e., water temperature. This study also investigates the result of the change in HTF flow rate on solidification and melting of phase change material. Finally, the study focuses on the comparison of average effectiveness for finned triplex tube heat exchanger and finned triplex tube with cylindrical holes on fin surface with rates of 0.33 and 0.43 Kg/s. The results showed that the average effectiveness with a finned triplex tube with a perforated fin surface is 4% more than that of a finned triplex tube at 0.33 Kg/s whereas it is 5 % more at 0.43 Kg/s during the charging process. On the other side during discharging process average effectiveness is 14 % more at 0.33 Kg/s and 11 % at 0.43 Kg/s.

Evaluation of Melting Mechanism and Natural Convection Effect in a Triplex Tube Heat Storage System with a Novel Fin Arrangement

In this research, a numerical analysis is accomplished aiming to investigate the effects of adding a new design fins arrangement to a vertical triplex tube latent heat storage system during the melting mechanism and evaluate the natural convection effect using Ansys Fluent software. In the triplex tube, phase change material (PCM) is included in the middle tube, while the heat transfer fluid (HTF) flows through the interior and exterior pipes. The proposed fins are triangular fins attached to the pipe inside the PCM domain in two different ways: (1) the base of the triangular fins is connected to the pipe, (2) the tip of the triangular fins is attached to the pipe and the base part is directed to the PCM domain. The height of the fins is calculated to have a volume equal to that of the uniform rectangular fins. Three different cases are considered as the final evaluation toward the best case as follows: (1) the uniform fin case (case 3), (2) the reverse triangular fin case with a constant base (case 12), (3) the reverse triangular fin case with a constant height (case 13). The numerical results show that the total melting times for cases 3 and 12 increase by 4.0 and 10.1%, respectively, compared with that for case 13. Since the PCM at the bottom of the heat storage unit melts slower due to the natural convection effect, a flat fin is added to the bottom of the heat storage unit for the best case compared with the uniform fin cases. Furthermore, the heat storage rates for cases 3 and 12 are reduced by 4.5 and 8.5%, respectively, compared with that for case 13, which is selected as the best case due to having the lowest melting time (1978s) and the highest heat storage rate (81.5 W). The general outcome of this research reveals that utilizing the tringle fins enhances the thermal performance and the phase change rate.

Experimental and numerical investigation on heat transfer enhancement of vertical triplex tube heat exchanger with fractal fins for latent thermal energy storage

Latent thermal energy storage (LTES) technology applied in the recovery of industrial waste heat, solar thermal applications, and energy conversation of buildings, etc. can solve the mismatches of thermal energy in supply and demand, space and time, and thus increasing the efficiency of thermal energy utilization. However, the heat transfer process in a latent heat exchanger(LHE) is limited due to the poor thermal conductivity of phase change material (PCM). Therefore, a vertical triple tube heat exchanger with fractal fins was applied to enhance the heat transfer process of the LTES system. The performance of the LHE with fractal fins was discussed and compared to that with traditional rectangular fins. The results manifest that fractal fins can effectively improve the heat transfer rate of the LHE by providing more heat flow channels and heat transfer areas. The total melting time of PCM in the LHE with fractal fins is reduced by 27.3% compared to that with rectangular fins during the heat charging process. Furthermore, the structure of fractal fin is optimized through a heat transfer model and numerical simulation. It was apparent from the simulation results that the PCM melting time of the LHE with optimized fractal fins is reduced by 35.6% compared with that of rectangular fins. It was also proved that the dual-channel structure is used to reasonably arrange the charging and discharging processes, which can make the LTES system achieve better results.

An analysis of latent heat thermal energy storage in a hexagonal triplex-tube unit with curve shape fin and CNTs

In this article, latent heat thermal energy storage (LHTES) is analyzed for nano phase change material enclosed in a hexagonal triplex-tube with solidification acceleration. Optimized curve shape fins are adjusted inside the tube. The shape of the structure is a hexagonal annular. Therefore, both inner hexagonal walls are cold. Corresponding to six vertices of the hexagonal shaped tube, parallel but symmetrically curved fins are adjusted to every corner. Nanoparticles Enhanced Phase Change Material (NEPCM) is filled inside the annulus, and the mathematical model is constructed based upon the system of nonlinear partial differential equations through the heat equation. Single wall carbon nanotubes (SWCNT) and Copper driven through liquid phase and solid phase within the entire duct. Galerkin Finite Element Method (GFEM) is employed to model the solidification procedure. The smaller symmetric fins achieving an angle of 10o≤β1≤45o and the larger symmetric fins making an angle of 10o≤β2≤45o with the vertical rod. However, the length of rod is 10mm≤L≤20mm. It is found that the optimized curve shape fin penetrate the intensity of thermal storage into the Phase change materials (PCM) and the shape of the fin prevents the phase trade manner from final unsolidified PCM near the outer shell, in which the phase alternate front passes the top of the fins. It is further analyzed that at the mean position of the triplex tube, the solidification process is minimum due to the high thermal performance of nanoparticle volume fraction and time perfection.

CFD simulation of an integrated PCM-based thermal energy storage within a nuclear power plant connected to a grid with constant or variable power demand

The current numerical study investigates the integration of a phase change material (PCM)-based thermal energy storage (TES) system within a nuclear power plant (NPP) to enhance the capability of such proposed plant to better follow the variations of power grid demand especially in countries with a high share of nuclear in their energy mix. This study focuses on the transient behavior of the PCM during the simultaneous charging and discharging (SCD) operation mode during one day. For this, an enthalpy-porosity method is used to simulate the SCD operation mode of PCM within an axisymmetric vertical triplex tube. Hot and cold heat transfer fluids (HTFs) are simultaneously co-circulating within the TES for downward-inner heating and upward-outer cooling. Constant and variable loads are considered to study the load-following ability of the coupled system. During the SCD mode with a constant load, results show that an equilibrium between melting and solidification (charging and discharging) is established and the liquid fraction (20%) is not changing with time. Under the variable load, the suggested TES system is able to follow the daily variation of the grid demand and, hence, fill the gap between reactor supplied energy and grid power demand with the reactor constantly operated at full rated capacity. During the variable load, the liquid fraction within PCM is altering from solid to liquid phases and vice versa depending on the deviations of the grid as expected.

Modeling of Multi-Layer Phase Change Material in a Triplex Tube under Various Thermal Boundary Conditions

Nowadays, limited energy resources face ever-growing demands of the modern world. One engineering approach to mitigate this problem which has received considerable attention in recent years is using latent heat thermal storage (LHTS) systems, a significant opportunity which is provided by phase change materials (PCMs). In the present study, a numerical investigation was devoted to estimate the simultaneous freezing and melting processes of a double-layer PCM in terms of heat transfer and fluid flow phenomena. A double-pipe cylindrical channel with two compartments, A and B, was considered for locating two PCMs of RT28 and RT35 in various arrangements. The inner and outer walls were exposed to both hot and cold heat transfer fluids (HHTFs and CHTFs, respectively) beginning with solid or liquid initial state, which led to solid–liquid phase change process through PCMs. The numerical simulation was handled by a two-dimensional finite volume method (FVM) with a fixed Rayleigh number of 106 in which conduction and convection heat transfer mechanisms are taken into account. The effects of employing double-layer PCM and their arrangements, inner and outer walls’ boundary conditions, and initial statuses of PCMs are discussed, and the details of the compared results are shown in the form of temperature and liquid fraction variations over time.

Enhancing PCMs thermal conductivity: A comparison among porous metal foams, nanoparticles and finned surfaces in triplex tube heat exchangers

Increasing latent heat thermal energy storage system thermal conductivity is of primary importance to take advantage of their capability of storing large amount of thermal energy. For this task, various solutions have been proposed through the years and a throughout comparison depending on the final application is still lacking. In this paper, the melting process of PCMs embedded in a Triplex-Tube Heat Exchanger (TTHX) is investigated numerically by considering three different methods that include separately or together metal foams, nanoparticles addition and finned surfaces. Organic PCMs with different melting points are used as PCMs in the middle shell of the 3D (TTHX) to maximize latent heat depending on local temperatures. Water across inner and outer tubes is considered too as the heat transfer fluid. Results are presented in terms of liquid fraction, temperature evolution as well as charging the energy storage rate. The results show that a composite of PCM/Metal Foam with porosities that vary from 0.98 to 0.92 engenders shorter melting comparing to pure PCM. By inserting metallic foam with different porosities and nanoparticles with 5% volume fraction in the TTHX (Case A), the melting time decrease can achieve a 69.52% when compared with Pure-PCM. Regarding the melting process in pure Multilayer-PCM (Case B), for all metal foam porosities the foam/nano-PCM device shows a shorter melting time even if nanoparticles have minor impact compared to metal foams, reaching a 83.48% in terms of reduction if nanoparticles and metal foams are employed. Finally, for the Case C, melting times are smaller when comparisons are done with Cases A and B for pure PCM. Furthermore, in the finned surfaces of TTHX (Case C), the inclusion of nanoparticles with foam reduced the melting durations by 53.17% compared to the TTHX (Case A) with pure PCM.

Entropy generation characteristics of phase change material in a variable wavy walled triplex tube latent heat storage unit for battery thermal management system

This study focuses on the thermal and frictional entropy generation characteristics of phase change material (PCM) in a triplex tube latent heat storage unit which is a promising technique for thermal management of lithium-ion batteries. Four different wavy structures for the triplex tube heat exchanger with variable waviness are considered, namely Case 1 to 4. Regarding the numerical analysis, the variations in mean temperature and liquid fraction of PCM are first revealed and presented where the crossflow heat transfer fluid in the system is considered water. Furthermore, thermal and frictional entropy generation rates in local and global means are separately discussed for both charging and discharging processes. The results showed that the difference in mean temperature and melting rates among the cases are more noticeable at the end of the process due to intensified natural convection, and Case 3 has 240 s (12.3%) shorter melting time compared to Case 1 and 4. Although solidification rates have similar trends in all cases, the solidification time is different, e.g., it is 110 s (5.2%) shorter in Case 4, compared to Case 1. The entropy generation trends are relatively similar during the solidification, while they are noticeably different in the melting process due to effect of liquid PCM flow.

Melting performance assessments on a triplex-tube thermal energy storage system: Optimization based on response surface method with natural convection

The low thermal conductivity of phase change materials significantly affects the heat storage and release performance for a phase change energy storage system. To alleviate this issue, a novel triplex-tube latent heat thermal energy storage system is designed and the melting behavior of phase change materials is studied numerically. On the premise of a fixed total volume of phase change material, the multi-parameter optimization design of the system is carried out by the response surface method. The fluid-structure coupling function of each parameter is fitted. Compared with the original model for the triplex tube, the melting performance of the optimized model is improved by 23.87%. The internal temperature fluctuation is found by dynamic temperature response, and the mechanism is explained by dynamic flow rate study. The improvement of melting performance by natural convection after optimization is also studied. The influences of the physical parameters (fin length, initial temperature of phase change material, inner and outer tube wall temperature, and fin material) of the optimization model on the melting performance of the system are quantified, as well. The effect of fin length (30-35-40 mm) on melting performance is found to be less than 11.47% and the effect of thermal conductivity of fin on the melting process is not obvious.

Thermal Management of the Melting Process in a Latent Heat Triplex Tube Storage System Using Different Configurations of Frustum Tubes

In this study, the energy charging mechanism is mathematically modeled to determine the impact of design modifications on the thermofluidic behavior of a phase change material (PCM) filled in a triplex tube containment geometry. The surface area of the middle tube, where the PCM is placed, is supported by single or multi‐internal frustum tubes in vertical triplex tubes to increase the performance of the heating and cooling of the system. In addition to the ordinary straight triplex tubes, three more scenarios are considered: (1) changing the middle tube to the frustum tube, (2) changing the inner tube to the frustum tube, and (3) changing both the internal and central tubes to the frustum tubes. The impact of adopting the tube designs and gap width were studied. The outcomes reveal that the heat storage rates are increased for all frustum tube systems compared to the straight tube system. According to the results, the case of a gap width of 5 mm is the optimal one among the studied cases in terms of the melting time and the heat storage rate. Employing the frustum tube configuration with a 5‐mm gap width would save the melting time by 25.6% and increase the rate of heat storage by 32.8% compared to the base case of straight tubes.

Influence of longitudinal fin arrangement on the melting and solidification inside the triplex tube latent heat thermal storage system

A two-dimensional melting/solidification model of Phase Change Material (PCM) is developed. The present research has studied the novel PCM based Triplex Tube Latent Heat Storage System (TTLHSS). The primary target of this research is to establish the effect of longitudinal fins on the performance of both melting and solidification rate of PCM. Initially, melting and solidification enhancement with four longitudinal fins are studied, and 60% and 46.15% reduction are observed in melting and solidification time. Then, the arrangement of fins inside TTLHSS is studied, and it is found that TTLHSS with three fins in the bottom portion can be more effective for melting enhancement. However, three fins in the bottom portion are not found beneficial for solidification enhancement. Then, instead of straight fins, l-shaped longitudinal fins are studied and found almost similar enhancement in melting as straight fins. At the same time, a 2–5% reduction in solidification time is observed with l-shaped fins. For further improvement, a greater number of fins with small lengths are examined. The fin volume remains the same in this case of eight fins and found good improvement in the melting and solidification processes. In short, three different parameters, fin arrangement, fin shape, and a number of fins are studied in current research. The case with a greater number of fins with reduced length is found maximum effective. The arrangement with eight fins (in which bottom fin length is increased with compensation of reduced side fin length) is found most effective with a 60.77% reduction in combined melting-solidification duration.