Fin Shape Research Articles

Enhanced Heat Transfer Performance of a New Horizontal Buried Tube Heat Exchanger

Horizontal buried heat exchangers cost less than vertical buried heat exchangers, but they need more land area. In order to reduce the required land area of horizontal buried tube heat exchanger, a finned strengthened heat exchanger pipe was designed to enhance the heat transfer performance, and a three-dimensional research model of shallow geothermal utilization system was established in Chengdu area . In this paper, the optimal shape and arrangement of fins are investigated, and the effects of inlet velocity, soil type, ambient temperature and intermittent operation on the enhanced heat transfer performance are studied. The results show that the enhanced heat transfer performance of rectangular fins is the best in the case of horizontal arrangement. The working fluid flow rate should not exceed 0.3m/s.Soil type has a great influence on heat transfer performance. The heat transfer of rock and soil is the largest, the heat transfer of clay is the smallest, but the strengthening effect of clay is the best. The longer the system runs, the obvious the influence of ambient temperature is, and the heat transfer efficiency increases by about 4% when the ambient temperature drops by 5K.

Numerical analysis on the thermal performance of microchannel heat sinks with Al2O3 nanofluid and various fins

• A single-phase three-dimensional flow model compares different finned microchannels. • The fin shape has significant effects on microchannel heat transfer characteristics. • A zigzag fin gives the highest rate of heat removal to hydraulic power loss ratio. • The zigzag fin gives a 9 K lower contact temperature and 60% higher Nusselt number. • Higher thermal performance is achieved with the Al 2 O 3 nanofluid compared to water. The hydraulic and thermal performance of microchannel heat sink configurations for high performance electronic cooling applications is investigated by numerical modelling. Conjugate heat transfer simulations are obtained through the silicon walls and the fluid domain of a square base prism heat sink traversed by 50 parallel rectangular cooling ducts, under a 150 W/cm 2 constant heat flux input through the base. Al 2 O 3 nanofluid coolant with a nanoparticle volume fraction ranging from 0 to 3% is supplied at 298 K, over the Reynolds number range 100 to 350, modelled as a single-phase homogeneous medium. Rectangular, twisted, and zig-zag fins are inserted into the plain rectangular duct to enhance the heat transfer rate. The zig-zag fin and 3% Al 2 O 3 nanofluid provide the best thermal performance, with a 6.44 K lower average heated wall contact temperature, 60% higher Nusselt number, and 15% higher second law efficiency than without fins and plain water cooling. Twist in the microchannel fin unexpectedly reduced the microchannel pressure drop by 2% to 15% compared to a straight fin, possibly due to the more evenly distributed axial mass flux across the microchannel.

Experimental quantification of air-side row-by-row heat transfer coefficients on fin-and-tube heat exchangers

• Mass transfer experimental method to visualize and quantify local air-side HTCs. • Local and averaged HTCs on real-scale HX aluminum fin surfaces. • HTC comparison between fin-and-tube HXs with inline and staggered tube arrangement. • Row-by-row HTC degradation of plain fin-and-tube HXs at various Re. • Correlations of averaged HTC and pressure drop on measured HX fin geometry. An absorption-based mass transfer method has been employed in the current study to obtain two-dimensional HTC distributions on two different 8-row fin-and-tube heat exchangers. The method utilizes a color change coating material and a tracer gas to quantify local mass transfer on the fin surfaces and then employs the heat and mass transfer analogy to calculate local air-side HTCs. The accuracy and robustness of the method were validated in previous studies. The current study focuses on investigating the row-by-row HTC degradation by increasing the number of tube rows. The local HTC measurements of the current study ranged from 0.5-4.8 ms −1 face airflow velocity using dry fin surfaces. The two 8-row fin-and-tube heat exchangers have the same tube diameter, tube pitch, fin pitch, and fin shape. The only difference is the staggered vs. inline arrangement of the tube bundle. Averaged HTCs of each row are quantified and compared. The results show HTC degradation is related to the tube arrangement, airflow velocity, and row number. The heat exchanger with inline tube arrangement shows a more substantial HTC degradation than the heat exchanger with the staggered tube arrangement. The maximum HTC decline is observed on the second row with 40% compared to the first row while flow velocity is below 1 ms −1 . The row-by-row HTC degradation becomes less significant for higher flow velocities. HTC degradation appears to be negligible past the 5 th row. The current study provides a method that can be used to predict air-side HTCs of fin-and-tube heat exchangers with multiple rows.

Numerical Simulation of Heat Transfer Tube Characteristics of Refrigeration and Air Conditioning Based on Mixed Fractional Model

The main parameters affecting the heat transfer performance of heat transfer tube heat exchanges include fin shape, fin spacing, fin thickness, tube row arrangement, tube diameter, dry and wet bulb temperature and flow rate. The air side heat transfer performance of heat transfer tube heat exchange and the influence of velocity field and temperature field distribution on heat transfer effect have been the focus of domestic and foreign scholars. In this paper, based on the mixed fraction model, CFD software is used to simulate the absorption process of gravity falling film outside the heat transfer tubes of refrigeration and air conditioning, and to study the flow and heat transfer characteristics of the process. The results show that, for the heat transfer tubes with the selected structure, the heat transfer capacity increases with the increase of water flow velocity, and the heat transfer enhancement effect of turbulence is enhanced. The heat transfer tubes have better comprehensive heat transfer performance than smooth tubes with the same diameter.

Influence of microheater patterns: MoSi2-SnO2 as energy-saving chemiresistors for gas sensing applications

In this article, we study the effect of various geometrical patterns (meander, spiral, and fin shape) of composite MoSi2-SnO2 microheater films towards an energy-saving approach for hydrogen gas sensing. The MoSi2-SnO2 microheater was prepared by using the screen-printing technique on a Si wafer. The structural and microstructural evolution characterization was done by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and field emission scanning electron microscopy (FESEM). The electrical characteristics were assessed by I-V measurements up to 8 V. The Joule heating effect was studied for printed patterns and correlated with the maximum temperature obtained in each case. We have compared the gas sensing properties of the composite MoSi2-SnO2 thin films according to the various geometrical patterns for hydrogen gas. The results show that the fin-shaped microheater provides more heating temperature (120 °C) followed by spiral and meander patterns due to a higher resistance change. The fin-shaped microheater pattern showed maximum temperature when operated at the same power levels from 0 to 20 mW. The fin-shaped structure microheater sensor was highly selective and had the optimum response and recovery times of 12 s and 27 s with a detection limit of 0.25 ppm. Based on these observations, the hydrogen sensing mechanism of MoSi2-SnO2 microheaters is discussed and reported here.

Performance enhancement of latent heat storage systems by using extended surfaces and porous materials: A state-of-the-art review

Latent heat thermal energy storage (LHTES) is a widely accepted technology because of its high energy density at nearly constant operating temperature. The main disadvantage of LHTES is the low thermal conductivity of the storage material, which affects the charging and discharging rates. Therefore, various methods have been used for enhancement of thermal performance of phase change materials in LHTES including utilizing fins and porous materials with high thermal conductivity. These two main methods are intensively addressed in the literature. In this paper, these techniques are reviewed and discussed by classifying them regarding their prominent specifications. First, the enhancement by extended surfaces is reviewed focusing on the fin geometries. Secondly, metal foams are investigated with respect to the materials they are made of and their structure such as gradient or partial porosity since these techniques are promising methods for significant performance augmentations. Thereafter, in the following section, the combination of these two techniques, which can be called a hybrid technique, is examined and recent research works are reviewed. The literature review showed that innovative fin shapes are increasingly investigated by numerical simulations. However, there is a significant need for experimental validations. On the other hand, metal foams exhibit remarkable thermal performance, nevertheless, their utilization is not as prominent as fins since utilization of fins is a simpler and cost-effective method. Combining these two methods is recently getting increasing attention as it can further improve thermal performance of PCMs. After reviewing the relevant recent studies, conclusions drawn from the present literature study are outlined. Additionally, some directions and recommendations for future research are highlighted at the end of the paper.

Numerical optimization of the fin shape experiments of a heat conjugate problem surface air/oil heat exchanger (SACOC)

Efficient aircraft engine designs imply the presence of a surface air/oil heat exchanger placed at the bypass flow separation of the engine. The heat exchanger consists of several parallel longitudinal fins that increase the contact area to obtain a higher heat dissipation rate. The design of these fins is an important task as the pressure drop generated by the presence of the heat exchanger is the largest drawback to be minimized in the final setup. Consequently, an efficient design of the fins that optimizes the global performance of the heat exchanger is highly demanded. The result of this optimization process should minimize the pressure drop caused by the exchanger without decreasing the heat transfer. The optimization methodology proposed in this work is split in two independent parts: in the first one, the fin shape is optimized using the adjoint method and the derived sensitivity function that controls the position of the fin shape design. In parallel, the range of fin thickness and distance between fins was investigated to have an optimized fin distribution for a given SACOC width. Once the geometry was optimized, the coupled conjugate heat problem is numerically solved using realistic conditions showing good accuracy in the two presented validations. The result for the optimized geometry presents a substantial pressure drop reduction with little heat transfer variation, addressing the objectives that motivated the present study.

Introgressive hybridization erodes morphological divergence between lentic and lotic habitats in an endangered minnow.

Introgressive hybridization may erode phenotypic divergence along environmental gradients, collapsing locally adapted populations into a hybrid swarm. Alternatively, introgression may promote phenotypic divergence by providing variation on which natural selection can act. In freshwater fishes, water flow often selects for divergent morphological traits in lake versus stream habitats. We tested the effects of introgression on lake–stream morphological divergence in the minnow Owens Tui Chub (Siphateles bicolor snyderi), which has been rendered endangered by introgession from the introduced Lahontan Tui Chub (Siphateles bicolor obesa). Using geometric morphometric analysis of 457 individual Tui Chub from thirteen populations, we found that both native and introgressing parent taxa exhibited divergent body and caudal fin shapes in lake versus stream habitats, but their trajectories of divergence were distinct. In contrast, introgressed populations exhibited intermediate body and caudal fin shapes that were not differentiated by habitat type, indicating that introgression has eroded phenotypic divergence along the lentic–lotic gradient throughout the historic range of the Owens Tui Chub. Individuals within hybrid populations were less morphologically variable than those within parent populations, suggesting hybrid adaptation to selective agents other than water flow or loss of variance by drift.

Chip-Scale Droop-Free Fin Light-Emitting Diodes Using Facet-Selective Contacts.

Sub-micron-size light sources are currently extremely dim, achieving nanowatt output powers due to the current density and temperature droop. Recently, we reported a droop-free fin light-emitting diode (LED) pixel that at high current densities becomes a laser with record output power in the microwatt range. Here, we show a scalable method for selectively metallizing fins via their nonpolar side facet that allows electrical injection to sub-200 nm wide n-ZnO fins on p-GaN with at least 0.8 μm2 active area. Electrically addressable fin LEDs are fabricated in a linear array format using standard 2 μm resolution photolithography. Electroluminescence analysis across different pixels shows that the fin acts as the active region of the LED and generates a narrow-band ultraviolet emission between ≈368 and ≈390 nm. Investigating fins at high current densities, ranging from 100 to 2000 kA/cm2, shows that their emission increases without any decline even as the junction temperature reaches a range of 200-340 °C. The absence of electron leakage to p-GaN at high injection levels and an undetectable electron-hole escape from the fin at high temperatures indicate that the fin shape is highly efficient in controlling the nonradiative recombination pathways such as Auger recombination. The fin LED geometry is expected to enable the realization of high-brightness arrays of light sources at sub-micron-size regimes suitable for operation at high temperatures and high current densities.

Performance Evaluation of H2/Air Premixed Combustion in a Suddenly Expanded Microcombustor with Wall Fin

Herein, a 2D, axisymmetric microcombustor with a backward‐facing step and triangular wall fin is considered for enhancement of combustor performance. The outer wall temperature, combustor efficiency, and pressure characteristics of the microcombustor are numerically investigated with a detailed chemical kinetic mechanism and conjugate heat transfer. The proposed microcombustors with variable blockage ratios, wall fin shapes, and locations are analyzed with respect to flow and combustion interaction, along with heat flux exchange between the flame and combustor wall. Combustion performance is also evaluated by means of the amount of heat transferred through the combustor wall, conversion ratio of input chemical energy to exploitable heat, and OH mass fraction distributions. Standard k–ε turbulence along with 9 species and the 19‐step combustion reaction scheme is implemented using the eddy dissipation concept (EDC) model in the numerical study. The results indicate that the wall fin blockage ratio alters the reaction zone and improves combustor performance significantly at lower inlet velocities (4–20 m s−1). The fin location and shape are observed to influence the temperature distribution. However, the higher blockage ratio adversely impacts the combustion characteristics at the higher inlet velocity, that is, 48 m s−1.

병어, Pampus punctatissimus와 덕대, Pampus argenteus의 외부 계측형질 특성

The external morphometric characteristics of silver pomfret, Pampus punctatissimus and Korean pomfret, P. argenteus of Stomateidae in Korea were investigated through direct distance. The 16 measurements were expressed as a ratio to the total length, resulting in 8 measurements of P. punctatissimus were found to be larger than those of the P. argenteus (p<0.05). The factors by components in the morphometric characteristics were extracted into three sub-factors, among which factor 1 was length component of species division, factor 2 was length component of body shape, and factor 3 was length component of pectoral section. As for the correlation between the length factor between P. punctatissimus and P. argenteus, DFL-DH showed the highest positive correlation by 0.923. The most remarkably distinguishable factor for the morphometric trait of Stomateidae was the length in dorsal and anal fin shapes, DH and AH, which were longer in the P. punctatissimus than in P. argenteus.

Form, function, and divergence of a generic fin shape in small cetaceans.

Tail flukes as well as the dorsal fin are the apomorphic traits of cetaceans which appeared during the evolutionary process of adaptation to the aquatic life. Both appendages present a wing-like shape associated with lift generation and low drag. We hypothesized that the evolution of fins as lifting structures led to a generic wing design, where the dimensionless parameters of the fin cross-sections are invariant with respect to the body length and taxonomy of small cetaceans (Hypothesis I). We also hypothesized that constraints on variability of a generic fin shape are associated with the primary function of the fin as a fixed or flapping hydrofoil (Hypothesis II). To verify these hypotheses, we examined how the variation in the fin's morphological traits is linked to the primary function, species and body length. Hydrodynamic characteristics of the fin cross-sections were examined with the CFD software and compared with similar engineered airfoils. Generic wing design of both fins was found in a wing-like planform and a streamlined cross-sectional geometry optimized for lift generation. Divergence in a generic fin shape both on the planform and cross-sectional level was found to be related with the fin specialization in fixed or flapping hydrofoil function. Cross-sections of the dorsal fin were found to be optimized for the narrow range of small angles of attack. Cross-sections of tail flukes were found to be more stable for higher angles of attack and had gradual stall characteristics. The obtained results provide an insight into the divergent evolutionary pathways of a generic wing-like shape of the fins of cetaceans under specific demands of thrust production, swimming stability and turning control.

Numerical study of entropy generation and forced convection heat transfer of a nanofluid in a channel with different fin cross-sections

PurposeThis study aims to numerically investigate the thermal-hydrodynamic performance of silicon oxide/water nanofluid laminar flow in the heat sink miniature channel with different fin cross-sections. The effect of the fin cross-section including semi-circular, rectangular and quadrant in two directions of flat and curved, and channel substrate materials of steel, aluminum, copper and titanium were examined. Finally, the analysis of thermal and frictional entropy generation in different channels is performed.Design/methodology/approachAccording to the numerical results, the highest heat transfer coefficients belong to the rectangular, quadrant 2, quadrant 1 and semi-circular fins compared to the channel without fin is 38.65%, 29.94%, 27.45% and 17.1%, respectively. Also, the highest performance evaluation criteria belong to the rectangular and quadrant 2 fins, which have 1.35 and 1.29, respectively. Based on the thermal conductivity of the substrate material, the best material is copper. According to the results of entropy analysis, the reduction of thermal irreversibility of the channel with rectangular, quadrant 1, quadrant 2 and semi-circular compared to non-finned channel is equal to 72%, 57%, 63% and 48%, respectively.FindingsThe rectangular and quadrant 2 fins are the best fins and the copper substrate material is the best material to reduce the entropy generation.Originality/valueThe silicon oxide/water nanofluid flow in the heat sink miniature channel with various fin shapes and the curvature angle against the fluid flow was simulated to increase the heat transfer performance. The whole test section is simulated in three-dimensional. Different channel materials have been investigated to find the best channel substrate material.

A comprehensive study on parametric optimization of the pin-fin heat sink to improve its thermal and hydraulic characteristics

In an effort to reduce the highest temperature of electronic pieces, using high performance cooling systems is required, and for this reason, optimization is one of the most essential and attractive issues that has an undeniable role in industry and technology. In this study, a finite volume method is employed to numerically simulate conjugate heat transfer in pin-fin heat sinks, which are of the most common cooling systems, and all the geometric parameters affecting their performance are optimized based on thermal and hydraulic performances (FOM). These geometric parameters are: the number of fins, the fin height, the fin diameter, and the transverse pitch. It will be shown that the total performance of the pin-fin heat sink improves step by step by optimizing these parameters. Also, it will be suggested that the shape of pin-fins changes to a tapered one. It is proved that changing the fin shape has a significant influence on the convective heat transfer coefficient and pressure drop and enhances the total performance of the system. Furthermore, it is observed that the total performance of the pin-fin heat sink increases more than 17% during the stages of the optimization.

Novel inverted fin configurations for enhancing the thermal performance of PCM based thermal control unit: A numerical study

• Novel fin configuration inside PCM is investigated to reduce the peak temperature. • Heat load: 11 W; Operating Time: 10, 12 min out of 100 min cycle. • Heating time, % mass, number, shape & cross-section of fins are studied numerically. • Temperature drop of 29 K is achieved through novel star inverted frustum fin. In the present study, the phase change material (PCM) based thermal control unit (TCU) has been analyzed to control the peak temperature (T pk ) of an electronic device. The pulsed heat load conditions are considered as an input to TCU. The PCM's low thermal conductivity is overcome by introducing the novel metallic fins, which are less complicated and easy to manufacture. Various parameters associated with the fin geometry are analyzed to identify fins' efficacy, namely, number of fins, % mass of fins, shape of fins, and cross-section of fins. Eight distinct fin configurations are studied viz. Prism – triangle and star; Frustum – triangle and star; Novel inverted frustum – circular, square, triangular, and star. The novel inverted fins have attained the highest area augmentation ratio with the lowest T pk of 331.41 K at 25% mass of fins than other configurations. An overall reduction in T pk is achieved around 9%, with novel inverted fins showing their significance inside PCM. The heating and cooling cycle ratio is 0.141, highest for the star inverted frustum at 25% mass of fin, suggesting that it can attain an initial temperature of 313 K way faster than other configurations.

Field synergy analysis for heat and mass transfer characteristics in adsorption-based desalination and cooling systems

Adsorption-based desalination and cooling system has gained particular interests for low-grade heat harvesting. In this study, field synergy analysis is conducted to illustrate the complicated heat and mass transfer characteristics in an adsorption-based desalination and cooling system with finned-flat beds via a dynamical three-dimensional computational fluid dynamics model. Two field synergy angles α and β reflecting the synergy effect of heat transfer and flow resistance with the adsorption driving force are examined. Results illustrate that smaller α and β result in better adsorption performance. Furthermore, guided by the field synergy analysis, adsorbent bed configurations (fin diameter, fin pitch, fin shape, and fin arrangement) are optimized. The fork-row arrangement results in a higher SCP and SDWP than that of the in-line arrangement. With the fin pitch of 20 mm and fin diameter of 12 mm, the system with fork-row arrangement demonstrates a SCP of 0.363 kW/kg and SDWP of 12.5 m3 per ton silica gel per day, which is 6.6% higher than that of the in-line arrangement as the field synergy parameter between heat transfer and the driving force factor (α) is more predominant at a relatively smaller fin pitch.

Simulation and analysis of heat dissipation performance of power battery based on phase change material enhanced heat transfer variable fin structure

The further development of battery thermal management phase change material (PCM) cooling technology is limited by the low thermal conductivity of a single PCM. In order to enhance the performance of thermal conductivity of phase change materials and improve the heat dissipation capacity of power battery, the fin with high thermal conductivity is used as a style of enhance heat transfer to phase change materials. The computational fluid dynamics (CFD) method is used to study the effect of parameters, such as shape, number and material of high thermal conductivity fins added in PCM as well as the air convection coefficient of shell on the heat dissipation performance of lithium ion power battery. The results show that the maximum temperature of the battery decreases the most, which is 5.57 K, when the oblique-oblique fins are added, compared with the fin without enhanced heat transfer in PCM. In the limited available space, the decrease rate of the maximum temperature of the battery does not increase with the increase of the number of oblique-oblique fins. When four oblique-oblique fins are added, the rate of decrease in the maximum temperature of the battery is the maximum, which is 0.47%. According to the thermal physical properties of each fin material and the simulation results, aluminum is the best choice for fin material. As for the convection coefficient of the air, the greater the value, the better the heat dissipation effect of the battery is.

Effects of fin parameters on performance of latent heat thermal energy storage systems: A comprehensive review

Due to the low thermal conductivity of the available phase change materials (PCM), fins are usually incorporated into latent heat thermal energy storage (LHTES) systems. Although many different fin configurations have been proposed and investigated, each assessment is performed with its unique assumptions and limitations. Therefore, the objective of the present paper is to provide a comprehensive review of various fin designs proposed for LHTES systems and critically discuss the effects of different geometrical parameters such as fin length, number, thickness, spacing, angle, and shape. The interaction between other design parameters (such as enclosure geometry and fluid flow rate and temperature) and fin configurations are also discussed. It is shown that an optimum number of fins, spacing, and length can be found in each case, while some parameters such as fin thickness are less important. However, the relationship between various design parameters is complicated, and finding an optimum fin arrangement for a wide range of operating conditions is a difficult task. Moreover, the superiority of different fin configurations cannot be addressed unless the operating and initial conditions are identical.

Effect of pin fin configuration on thermal performance of plate pin fin heat sinks

Flow behavior and heat transfer characteristics of air flow inside the plate pin fin heat sinks (PPFHS) are presented. The effects of pin fin shape, pin fin orientation, and ratio of distance between pin and plate fin center to pin fin size (S/Dp or S/Wp) on the flow pattern, heat transfer coefficient (HTC), pressure drop (ΔP) and thermal performance are investigated. Three types of pin fin shape, including a circular pin, square pin, and 45° square pin with pin fin sizes of 2.5, 3.0, and 3.5 mm, are used. The flow visualization used smoke to study the air flow behavior inside the PPFHS. The test runs were done at a heat flux of 14.81 kW/m2 and Reynolds number (Re) ranging between 1700 and 5200. Under the same pin fin frontal area, the HTC and ΔP of air inside the plate square pin fin heat sink (PSPFHS) was higher than that from the plate circular pin fin heat sink (PCPFHS) by an average of 12.52 and 15.05%, respectively. The decrease of the S/Dp or S/Wp from 2.25 to 1.61 caused the augmentation of the HTC and ΔP of air flow inside the PPFHS by about 11.77%–17.17% and 46.61%–50.52%, respectively. The average thermal performance factors (TPF) were 1.32, 1.44, and 1.42 for PCPFHS, PSPFHS, and the plate 45° square pin fin heat sink (P45oSPFHS), respectively. The correlations for Nusselt number (Nu) and friction factor (f) were also proposed.

Multi-objective NSGA-II based shape optimisation of the cross-sectional shape of passively cooled heat sinks

PurposeThe purpose of the study is to optimise the cross-sectional shape of passively cooled horizontally mounted pin-fin heat sink for higher cooling performance and lower material usage.Design/methodology/approachMulti-objective shape optimisation technique is used to design the heat sink fins. Non-dominated sorting genetic algorithm (NSGA-II) is combined with a geometric module to develop the shape optimiser. High-fidelity computational fluid dynamics (CFD) is used to evaluate the design objectives. Separate optimisations are carried out to design the shape of bottom row fins and middle row fins of a pin-fin heat sink. Finally, a computational validation was conducted by generating a three-dimensional pin-fin heat sink using optimised fin cross sections and comparing its performance against the circular pin-fin heat sink with the same inter-fin spacing value.FindingsHeat sink with optimised fin cross sections has 1.6% higher cooling effectiveness than circular pin-fin heat sink of same material volume, and has 10.3% higher cooling effectiveness than the pin-fin heat sink of same characteristics fin dimension. The special geometric features of optimised fins that resulted in superior performance are highlighted. Further, Pareto-optimal fronts for this multi-objective optimisation problem are obtained for different fin design scenarios.Originality/valueFor the first time, passively cooled heat sink’s cross-sectional shapes are optimised for different spatial arrangements, using NSGA-II-based shape optimiser, which makes use of CFD solver to evaluate the design objectives. The optimised, high-performance shapes will find direct application to cool power electronic equipment.