Shell Fluid Research Articles

A triple emulsion droplet in a uniform flow

The fluid mechanics problem of a triple emulsion droplet in a uniform creeping flow is theoretically studied. The triple emulsion, submerged in an external fluid 1, is composed of an inner spherical drop (fluid 4), covered by a spherical shell (fluid 3), which is subsequently covered by another spherical shell (fluid 2). In the absence of a body force, eight parameters are governed: the Capillary number (Ca), three viscosity ratios (λ21, λ32, λ43), two radii ratios (K, k), and two-surface tension ratios (M, m). If all surfaces remain spherical and concentric, five parameters (λ21, λ32, λ43, K, k) are sufficient. Expressions for the stream functions and the drag forces were obtained to calculate the terminal velocity of the triple emulsion falling or rising in a stagnant fluid under the influence of gravity. With gravity, four additional parameters are needed: the ratio of the buoyancy force to the external viscous force (B), and three density ratios (γ21, γ31, γ41). To remain concentric, all surfaces must have the same velocity (magnitude and direction). This results in two restricted parameters, but even then, not every combination of parameters leads to a physical solution. Our findings suggest that the terminal velocity of a triple emulsion is equal to or lower than that of a double emulsion, which is subsequently equal to or lower than that of a single drop. Similar to single and double emulsion droplets, no deformation takes place in a concentric spherical triple emulsion subjected to a gravitational field under creeping flow conditions.

Vibration-Enhanced Heat Transfer Analysis and Improvement of Spiral Elastic Tube Heat Exchanger

Using the fluid–solid coupling approach in fluid-induced vibration studies, the effect of flow-induced vibration on a heat exchanger is investigated. This paper analyzes the impact of flow parameters for shell fluid on heat transfer characteristics enhanced by the vibration of a spiral elastic tube bundle (SETB). Improvement schemes for heat exchangers are also proposed, and they are studied and compared. The results show that there is a positive correlation between the inlet velocity and the heat transfer coefficient of the SETB heat exchanger. As the inlet velocity rises to 0.9 from 0.3 m/s, the Nusselt number of the hollow SETB heat exchanger under vibration conditions is increased by 153.10, 45.55, and 26.73% sequentially. The vibration generated by impacting the elastic element during fluid flow can improve the Nusselt number effectively. As the flow velocity increases to 0.9 from 0.3 m/s, the flow-induced vibration enhances the Nusselt number of the hollow SETB heat exchanger by 2.13, 1.53, 1.05, and 0.89%. When the inlet flow velocity of fluid is in the range of 0.3–0.9 m/s, under the same flow velocity, same pressure drops, and same pumping power conditions, the performance of the improved heat exchanger is greater than that of the SETB heat exchanger before the structural improvement.

Suggestion of Correlations to Obtain Shell and Tube Side Nusselt Numbers in Coiled Heat Exchangers

In coiled tube heat exchangers increase in curvature ratio and effective contact of shell fluid with coil surface led to better thermal characteristics. This work addresses study of thermal performance, shell and tube heat transfer coefficients (ho and hi). Also, mathematical correlations are predicted to obtain shell and tube Nusselt numbers (Nuo and Nui). In the designing of compact coiled heat exchangers consisting of straight helical coil (SHC), conical coil (CC) and spiral coil knowledge of Nuo and Nui is necessary whereas mathematical correlation to calculate Nuo considering variations in shell geometry is not found. Five heat exchangers consisting of three cone coils (angle, ϴ = 30°, 50° and 70°), spiral coil (ϴ = 0°) and SHC (ϴ = 90°) are tested. Using Wilson plot method ho and hi are obtained for wide range of tube side Reynolds numbers (Rei = 3700 - 21000). It is observed that, highest ho is obtained for ϴ = 30°CC with better thermal performance. Lowest ho is obtained for ϴ = 90°SHC. Ratio of height of shell, Hs and diameter of shell, Dso is considered in prediction of single correlation as: Nuo = 16.55.Reo0.55.Pro0.4 *(Hs/Dso)0.096. Comparison with experimental findings shows variation of 0-14%. Similarly two correlations are proposed as: Nui = 0.0512.Rei0.80.Pri0.4.CRave0.18 and Nui = 0.0365.Dei0.815.Pri0.4.CRave-0.3. A fair agreement is found with existing researchers.

Hydrodynamic characteristics of core/shell microdroplets formation: Map of the flow patterns in double-T microchannel

Liquid-liquid–liquid (L/L/L) flows in microchannels involving three-phase interactions are important in various chemical applications that entail liquid–liquid–liquid reactions. This work comprehensively investigates core (silicone oil)/shell (Polycaprolactone) microdroplet formation using a continuous third phase (distilled water) in a double T-junction microchannel with a diameter of 600 µm, employing Volume-of-Fluid (VOF) simulations and high-speed imaging experimental observation. Due to the satisfactory agreement between computational and experimental techniques, the theoretical flow patterns were identified and categorized into three distinct categories at various flow rates of three phases: core/shell dripping, core/shell slug, and core/shell jetting. The shell thickness increases as the ratio of shell to core phase velocity (ushell:ucore) increases. Based on the continuous phase Capillary number (Cac) and core and shell phases Weber number (Wecore,shell), a flow pattern map was generated that segregates the distinct flow patterns into different regions. When the flow of the core and shell phases fails to form a droplet due to the inertia of the continuous phase, a core/shell dripping/slug pattern is observed. The channel walls encompass the droplets that form in the slug pattern (2×10-5≤Cac≤5×10-4, 0<Weshell≤1.5×10-3, and 0<Wecore≤5×10-5) because the continuous phase has less inertia, whereas, in the dripping pattern (5.5×10-5≤Cac≤9×10-4, 7×10-5≤Weshell≤2.5×10-4, and 1×10-5≤Wecore≤7×10-5), the shell phase fluid is enclosed by the continuous phase. The transition from dripping to jetting (Cac≥0.5, 0<Weshell≤0.15, and 1×10-2≤Wecore≤8×10-2) occurs as the flow rate of a continuous fluid or shell fluid increases. A dimensionless correlation for shell thickness estimation with a 12 % tolerance was proposed with a core/shell/continuous phase's physical properties, surface tensions, and microdroplet size, using Buckingham's theory based on 200 CFD simulations. Additionally, the flow rate and viscosity substantially impact the internal fluid velocity and vorticity of core/shell microdroplets, whereas the influence of interfacial tension can be disregarded. This research lays the groundwork for future studies on mass transfer and reaction behaviors in liquid–liquid–liquid three-phase flow in double T-junction microchannels by exploring various hydrodynamic characteristics under different operating conditions for core/shell microdroplet formation.

Innovative method for heat transfer enhancement through shell and coil side fluid flow in shell and helical coil heat exchanger

Innovative method for heat transfer enhancement through shell and coil side fluid flow in shell and helical coil heat exchanger

A triple emulsion droplet in an extensional flow

In this theoretical report we analytically explore the deformation and breakup of an initially spherical triple emulsion drop undergoing an axisymmetric extensional creeping flow. The triple emulsion, suspended in an external fluid (fluid 1), is originally made from an inner spherical drop (fluid 4), engulfed by a spherical shell (fluid 3), which is subsequently engulfed by another spherical shell (fluid 2). The problem is described by eight dimensionless parameters: the external capillary number (Ca), three viscosity ratios (λ21, λ32, λ43), two radii ratios (K, k), and two surface tensions ratios (M, m). When the triple emulsion is subjected to an external uniaxial extensional flow (Ca > 0), the outer interface (21) and the inner drop interface (43) deform into prolate spheroids, while the interface between them (32) deforms into an oblate spheroid. The reverse occurs for an external biaxial flow (Ca < 0), the outer interface (21) and the inner drop interface (43) deform into oblate spheroids and the middle interface (32) becomes a prolate spheroid. Three types of breakup mechanisms are to be expected: when the outer and the middle interfaces are in contact, when the middle and the inner interfaces are in contact, and when the inner drop breaks while the two shell phases remain continuous. Finally, an analytical expression for the effective viscosity of a dilute emulsion containing spherical triple emulsion droplets is suggested. For a triple emulsion which behaves like a solid: a very viscous or a very thin outer shell (λ21→∞ or K→ 1), the effective viscosity reduces to Einstein’s formula, and when the triple emulsion behaves like a single drop: a very thick outer shell such that the inner shell and the inner drop disappear (K→ 0), Taylor’s expression is recovered.

Finite Volume Computational Analysis of the Heat Transfer Characteristic in a Double-Cylinder Counter-Flow Heat Exchanger with Viscoelastic Fluids

This work presents a computational analysis of the heat-exchange characteristics in a double-cylinder (also known as a double-pipe) geometrical arrangement. The heat-exchange is from a hotter viscoelastic fluid flowing in the core (inner) cylinder to a cooler Newtonian fluid flowing in the shell (outer) annulus. For optimal heat-exchange characteristics, the core and shell fluid flow in opposite directions, the so-called counter-flow arrangement.The mathematical modelling of the given problem reduces to a system of nonlinear coupled Partial Differential Equations (PDEs). Specifically, the rheological behaviour of the core fluid is governed by the Giesekus viscoelastic constitutive model. The governing system of coupled nonlinear PDEs is intractable to analytic treatment and hence is solved numerically using Finite Volume Methods (FVM). The FVM numerical methodology is implemented via the open-source software package OpenFOAM. The numerical methods are stabilized, specifically to address numerical instabilities arising from the High Weissenberg Number Problem (HWNP), via a combination of the Discrete Elastic Viscous Stress Splitting (DEVSS) technique and the Log-Conformation Reformulation (LCR) methodology. The DEVSS and LCR stabilization techniques are integrated into the relevant viscoelastic fluid solvers. The novelties of the study center around the simulation and analysis of the optimal heat-exchange characteristics between the heated Giesekus fluid and the coolant Newtonian fluid within a double-pipe counter-flow arrangement. Existing studies in the literature have either focused exclusively on Newtonian fluids and/or on rectangular geometries. The existing OpenFOAM solvers have also largely focused on non-isothermal viscoelastic flows. The relevant OpenFOAM solvers are modified for the present purposes by incorporating the energy equation for viscoelastic fluid flow. The flow characteristics are presented qualitatively (graphically) via the fluid pressure, temperature, velocity, and the polymer-stress components as well as the related normal stress differences. The results illustrate the required decrease in the core fluid temperature in the longitudinal direction due to the cooling effects of the shell fluid, whose temperature predictably increases in the counter-flow direction.

Dynamic modelling and natural characteristics analysis of fluid conveying pipeline with connecting hose

As an important connecting component, the hoses transport fluid from pump to pipeline. However, the modeling of connecting hose has been rarely incorporated in the open research of pipeline modeling. To study the natural characteristics of fluid conveying pipeline and the effect of the connecting hose, a new dynamic model of pipeline with connecting hose is established by the finite element method. The measured support stiffness of clamp is introduced, and the equivalent boundary stiffness of connecting hose is identified based on the genetic algorithm (GA) and the measured frequency response function. The proposed model is verified by numerical examples and experimental results. Besides, the mixed finite element method (using shell element and fluid element) and the transfer matrix method are used to verify the natural characteristics of the proposed model under different fluid excitation. Moreover, the effect of fluid pressure on natural frequency of pipeline is analyzed. The results show the proposed model has higher precision than other models, and the average error is 0.55%. When the pressure increases from 0 MPa to 15 MPa, the natural frequency of pipeline decreases and the decline rate decreases with the increase of modal order. This paper provides the theoretical and experimental basis for the practical engineering requirements, and the proposed model can be more comprehensive to study the natural characteristics in fluid conveying pipeline.

Large-amplitude vibrations of thick cantilevered circular cylindrical shells containing still fluid

In the present study, for the first time, thick and moderately thick shells with clamped-free boundary conditions are modeled according to the third-order shear theory with thickness stretch. Then using Lagrange relations, the governing differential equations of the system in terms of shell–fluid​ interaction are derived and the solution method of the equations is also presented. The linear and nonlinear free vibration of cantilevered circular cylindrical shell containing quiescent fluid is investigated and the effects of shell thickness, length and fluid relative height are studied. In linear free vibration analysis, it was observed that the presence of fluid reduces the fundamental frequency of the system and the number of circumferential waves of the fundamental mode, especially in the thin shell. Also, increasing the height of the fluid, strengthens the decreasing fundamental frequency of the system. In nonlinear analysis, it was found that the presence of fluid, mainly weakens the nonlinear behavior in the thin/thick shell. Also, it was found that with increasing shell thickness, the effect of fluid on the nonlinear behavior of the system decreases, and the shell behavior is more dominant in the system. In addition, the presence of fluid has mainly reduced the peripheral contraction of the shell caused by the large amplitude circumferential waves, so that peripheral contraction approaches zero in the fully filled thin shell.

Mathematical modeling for transient thermal performance analysis of phase change material-based heat exchanger

Thermal energy storage (TES) provides a unique way for the thermal solutions to short-duration thermal load systems. TES system utilizes phase change material (PCM), wherein energy is stored in latent heat during the lean time and released during peak load. Conventionally, in a shell-and-tube PCM heat exchanger, PCM is stored in the shell and heat transfer fluid (HTF) flows in the tube. Numerical modeling based on computational fluid dynamics (CFD) tools like FLUENT and COMSOL are computationally intensive. Most numerical research is based on the enthalpy porosity model for solidification/melting problems. Enthalpy-porosity model requires a mushy zone parameter constant which significantly affects analysis results. The constant has no theoretical basis and is chosen based on experience. Analytical models in literature cannot give reasonably good results, which can be directly utilized for engineering purposes. This paper establishes a mathematical model based on the effectiveness-NTU (e-NTU) technique for transient analysis/rating of such PCM heat exchangers. Transient behavior of PCM heat exchanger due to phase transforming static PCM are modeled using an innovative concept of PCM zones, effective zonal length of heat exchange, and PCM zonal resistances. These functions are dependent on one dimension – total PCM liquid fraction ‘xf’ and a model is established for evaluating thermal performance analysis and optimization of PCM heat exchangers. The model is validated against published experimental results for cumulative energy stored in PCM of a PCM heat exchanger with air as HTF. The root-mean-square error for evaluated & predicted model results is less than 2.5%. The model proposed is uncomplicated and can be further utilized to optimize PCM heat exchangers. Transient analysis of inlet–outlet HTF temperature difference, PCM heat exchanger effectiveness, total PCM liquid fraction, PCM phase fractions, and zonal heat exchange length ratios of PCM heat exchanger for the respective experimental cases is further investigated.

Propagation of waves in a hydroelastic shell‐viscous liquid system, in the presence of gas bubbles

In this article, a thin‐walled isotropic infinitely long‐circular cylindrical elastic tube and the pulsed flow of an aerohydroelastic system within a compressible bubble fluid have been presented in 3D. The equation has been solved for an axisymmetric waves propagation in the liquid–shell system. The form and frequency of the specific oscillations formed in the shell–fluid dynamic system have been determined. The results obtained for the case when the material of thin‐walled pipes is made from various modifications of high‐strength steel and non‐classical polymeric materials, and water containing spherical air bubbles is taken as a two‐phase liquid. The fundamental iteration technique has been used to compute eigenvalues and corresponding eigenfunctions to represent field quantities with the help of Matlab software. The numerical results have been presented graphically.

The shell shape optimization and fluid\u2013structure interaction simulation of hose pump in water-fertilizer integrated fertilizer application

As a new type of under-film drip irrigation, water-fertilizer integrated fertilizer application device in Northwest China, the hose pump has achieved excellent results in practical applications, but its pulsation has exhibited some adverse effects on the fertilization process. By analyzing the cause of pulsation and flow characteristics, we proposed a shell optimization method to reduce pulsation. We used a release time deformation curve as the shape curve of the outlet shell of the hose pump. Based on the fluid–structure interaction analysis, we developed a numerical model of an optimized three roller hose pump and a conventional three roller hose pump for dynamic simulations. The simulation results showed the optimized hose pump flow pressure variation range was reduced by 26.92%, the average fluid flow velocity increased by about 10%, and mass flow rate improved by 8.84% over the conventional hose pump. We tested the optimized hose pump prototype and the conventional hose pump on the test bench. The test results showed that the pulsating pressure variation range of the optimized pump decreased by about 20%, and flow output increased by about 8.63%. These results suggest that shell shape optimization assist in the decrease of flow pulsation and contribute to further hose pump popularization.

Experimental and Numerical studies on the Heat transfer characteristics of Small Shell and Tube Heat Exchanger

This work presents the experimental and numerical investigations on the effectiveness of a small shell and tube heat exchanger for different coolant combinations. A numerical investigation is done using commercial computational tool, Fluent, to analyze heat transfer characteristics for the selected coolant combinations. The coolant combinations used consists of ethylene glycol (EG) and deionized water (DW) with varied percentages of the former. Accordingly, combination of ethylene glycol (EG) and deionized water viz, 60EG:40DW, 30EG:70DW and 20EG:80DW were used. The base fluids of EG and DW were used for the comparison of heat transfer characteristics, respectively with the selected coolant combination. For the numerical investigations, the CAD model of counter flow heat exchanger with 0 degree inclined baffles; with cold liquid flowing through the shell at the rate of 0.3 kg/s while hot liquid flows through the copper tubes at a flow rate of 0.3 kg/s was considered. Different combinations of shell-tube liquid are analyzed for identical initial and boundary conditions, keeping all other Fluent parameters the same. The temperature contours are generated for all the five cases. The temperature distribution for different shell-tube liquid combinations are compared for evaluating the effectiveness of heat exchange.Improved heat exchange is ensured with higher temperature difference between inlet and outlet of shell/tube, and respective combination of shell and tube fluid is selected for industrial cooling applications. Results of CFD approach are validated with the experimental results and results are acceptable. From the results it is found that 60EG:40DW combination showed improved heat transfer characteristics compared to other combinations used. Among the different coolant combinations, 60EG:40DW showed higher heat transfer as indicated by higher temperature difference across both shell and tube sections followed by other combinations when compared to pure ethylene glycol. Shell outlet and Tube outlet temperature with 60EG:40DW increased by 227% and 105% respectively when compared with pure EG, due to improved heat exchange. Heat transfer rate, heat transfer coefficient with 60EG:40DW increased when compared to pure EG.

Novel in-capsule synthesis of metal–organic framework for innovative carbon dioxide capture system

Metal-Organic Frameworks (MOFs) have been developed as solid sorbents for CO2 capture applications and their properties can be controlled by tuning the chemical blocks of their crystalline units. A number of MOFs (e.g., HKUST-1) have been developed but the question remains how to deploy them for gas–solid contact. Unfortunately, the direct use of MOFs as nanocrystals would lead to serious problems and risks. Here, for the first time, we report a novel MOF-based hybrid sorbent that is produced via an innovative in-situ microencapsulated synthesis. Using a custom-made double capillary microfluidic assembly, double emulsions of the MOF precursor solutions and UV-curable silicone shell fluid are produced. Subsequently, HKUST-1 MOF is successfully synthesized within the droplets enclosed in the gas permeable microcapsules. The developed MOF-bearing microcapsules uniquely allow the deployment of functional nanocrystals without the challenge of handling ultrafine particles, and further, can selectively reject undesired compounds to protect encapsulated MOFs.

Mass transfer around a double emulsion droplet in a uniform flow

The transfer of mass around a spherical double emulsion droplet in a uniform creeping flow and at large Peclet numbers is the subject of this theoretical communication. The double emulsion droplet, submerged in an external fluid (fluid 1), is made from an internal spherical drop (fluid 3) covered by a spherical fluid shell (fluid 2). Four dimensionless numbers describe this situation: two viscosity ratios, shell over external (λ21) and internal over shell (λ32); the radii ratio, inner over outer (κ); and the Peclet number (Pe). The external mass transfer rate of a double emulsion having a fast external mobile surface is proportional to Pe1∕2, it increases as λ21 or κ decrease, and for a very small internal drop or a very thick shell (κ→ 0), it behaves like a single drop. On the other hand, the external rate of mass transfer of a double emulsion with a very slow external mobile surface is proportional to Pe1∕3, it increases as λ21 or κ increase, and for a very large internal drop or a very thin shell (κ→ 1), it mimics a single solid particle. The influence of the other viscosity ratio (λ32) on the external mass transfer can be ignored.

Design and Performance Prediction of a Compact MmNi4.6Al0.4 based Hydrogen Storage System

The present work is focused on the design and numerical prediction of hydrogen storage performance of a compact MmNi4.6Al0.4 based hydrogen storage unit. Two types of shell and tube reactors capable of holding the same amount of metal alloy are compared for hydriding performance using a 3-D numerical model realized in COMSOL Multiphysics 5.3. The first configuration is an Embedded Cooling Tube (ECT) model where the alloy is contained in the shell and Heat Transfer Fluid (HTF) flows through the tubes; whereas in the second configuration, the alloy is contained in the tubes, which is termed as tube bundle (TB), and HTF flows over the tube bundle inside a shell. The TB configuration showed marginally better initial hydriding rate as compared to the ECT configuration and yielded 1.17 times higher alloy-to-container weight ratio. Based on the TB configuration design methodology, a metal hydride based hydrogen storage unit of 100 kg alloy capacity was proposed, where 4 tube bundle modules of 25 kg alloy capacity each could be arranged in parallel. A parametric study was conducted on the 25 kg reactor module to analyse the effects of various operating parameters viz. supply pressure, HTF temperature and convective heat transfer coefficient on hydrogen storage behaviour. Numerical study predicted that the MH module could store 307.5 g of hydrogen in 600 s, when subjected to 30 bar supply pressure at 298 K HTF temperature, whereas 292.5 g of hydrogen could be discharged at 1 bar, in 1000s, at 303 K HTF temperature.

Deformation of an Encapsulated Leukemia HL60 Cell through Sudden Contractions of a Microfluidic Channel.

Migration of an encapsulated leukemia HL60 cell through sudden contractions in a capillary tube is investigated. An HL60 cell is initially encapsulated in a viscoelastic shell fluid. As the cell-laden droplet moves through the sudden contraction, shear stresses are experienced around the cell. These stresses along with the interfacial force and geometrical effects cause mechanical deformation which may result in cell death. A parametric study is done to investigate the effects of shell fluid relaxation time, encapsulating droplet size and contraction geometries on cell mechanical deformation. It is found that a large encapsulating droplet with a high relaxation time will undergo low cell mechanical deformation. In addition, the deformation is enhanced for capillary tubes with narrow and long contraction. This study can be useful to characterize cell deformation in constricted microcapillaries and to improve cell viability in bio-microfluidics.

Mass transfer around a compound drop in an extensional flow

AbstractMass transfer around a spherical compound drop in an extensional creeping flow and at large Peclet numbers is theoretically studied. The compound drop, embedded in an external fluid (fluid 1), is composed from a spherical inner drop (fluid 3), which is engulfed by a spherical fluid shell (fluid 2). The study is governed by four dimensionless parameters: two viscosity ratios, shell over external fluid (λ21) and internal drop over shell (λ32); the radii ratio, inner over outer (κ); and the large Peclet number (Pe). For very fast mobile interfaces, the rate of mass transfer is proportional to Pe1/2, it increases as λ21 or κ decrease, and in the limit of a very small internal drop (κ → 0) it reduces to the case of a single drop. For very slow mobile interfaces or immobile interfaces, the rate of mass transfer is proportional to Pe1/3, it increases as λ21 or κ increase, and in the limit of a very thin shell (κ → 1) it behaves like a single solid particle. For both interface speed cases, the effect of the other viscosity ratio (λ32) on the external mass transfer is practically negligible.

Failure analysis of a ruptured compressor pressure vessel

This paper deals with failure analysis of a ruptured pressure vessel that served as a part of an air compressor. Pressure vessel failed during hydrostatic test when, at a pressure level lower than proof pressure, two cracks occurred on the shell and test fluid leakage was recorded. Experimental investigation methods were employed to determine possible causes of crack occurrence and vessel rupture. Liquid penetrate inspection was performed to check for other surface-breaking defects on the shell and locations of the cracks. Visual examination revealed the condition of the internal surface of the shell. Optical microscopy was used to inspect crack area while scanning electron microscopy examination at suitable magnification was employed to characterize fine microstructure of the fractured surface and to reveal flaws that served as rupture initiation points. Material’s chemical composition was determined using optical emission spectrometer with glow discharge source sample stimulation. Hardness test results were used to derive maximum tensile strength of the material. According to results obtained from performed investigations, it was concluded that excessive corrosion at the bottom part of the pressure vessel caused formation of pits that served as initiation points for leakage cracks. Recommendations for avoidance of such scenario with the rest of the user’s compressor pressure vessel were given. Also, ultrasonic testing of shell thickness was performed and results of the performed hydrostatic pressure test were recorded to be used in subsequent numerical failure analysis of the failed pressure vessel.

Experimental Analysis of Shell and Tube Heat Exchanger with Circular Fin by Using Compatible Liquids

The scope of our project is to increase the effectiveness of the shell and tube heat exchanger by attaching circular fin. Hence by using circular fin contact area is increased which leads to more heat transfer. Fins are attached to retain the heat for a certain period of time. We use both shell and tube fluid as water, Ethylene Glycol and propylene Glycol Shell carries cold water and tube carries hot water. Baffles are arranged inside shell for structural rigidity and to divert the flow across the bundle to get high heat transfer coefficient. Tube bundle is arranged in triangle pitch pattern to get high effectiveness. After the fabrication process the equipment has been tested for different temperature and different mass flow rate. Mass flow rate of both hot water and cold water is varied to get optimum effectiveness of heat exchanger.