Vertical Rows Research Articles

Laonicespecies (Polychaeta, Spionidae) from the Whittard Canyon (NE Atlantic) with descriptions of two new species

Four species ofLaonice(Annelida: Spionidae) were collected from the lower bathyal depths (3300–3700 m) in the Whittard Canyon, NE Atlantic. Two are herewith described as new species:Laonice whittardensissp. nov. andLaonice nataesp. nov. The other two areLaonice blakeiSikorski & Jirkov, 1988 andLaonice magnacristataMaciolek, 2000.Laonice whittardensishas genital pouches appearing from chaetiger 3, prostomium free of peristomium and bidentate hooks.Laonice nataebelongs to the subgenusAppelloefianov. with prostomium distinct from the peristomium, more than two vertical rows of capillaries in several anterior chaetigers, genital pouches present on a limited number of segments or totally absent. However, the absence of pronounced anterior widening of the body together with anterior branchiae, which are remarkably (nearly twice) longer than the notopodial postchaetal lobes, the narrow lanceolate notopodial postchaetal lobes, the pronounced pointedness of all postchaetal lobes (both notopodial and neuropodial) in the anterior half of body at least, and absence of genital pouches and the size of the body all distinguishL. nataefrom other species belonging to this subgenus. An identification key to all nine known deep-water (>400 m depth)Laonicespecies in North Atlantic is given and four previously recognized sub-generic groups are formally named:Laonice, Sarsianasubgen. nov.,Appelloefiasubgen. nov.,Norgensiasubgen. nov.

Modeling of Batter Pile Behavior under Lateral Soil Movement

Pile foundation is frequently used when structures are located on weak sublayers or are at risk from lateral loadings such as earthquakes. The design of pile foundations has recently become crucial to stop slope movement. To understand the behavior of pile foundations subjected to lateral soil movement, the three-dimensional Fast Lagrangian Analysis of Continua (FLAC3D) program was used to perform numerical simulations, which can reduce the cost of field testing. Vertical piles and batter piles were combined into 3 × 3 pile groups, and the response of batter piles to soil movement was analyzed. The outer batter piles led to an increased bending moment in the middle, vertical pile row. Increasing the pile spacing and the presence of battered piles reduced the pile group’s displacement. The batter pile group’s maximum bending moment was smaller than the vertical pile group’s in sand soil, but 5–8 times higher in clay soil.

Two new species of Trimma (Pisces; Gobiidae) from Fiji, south-western Pacific Ocean.

Two new species of Trimma are described from Fiji. Trimma bathum n. sp. lacks scales on the cheeks, opercle and predorsal midline, has 18-19 unbranched pectoral fin rays, an unbranched 5th pelvic fin ray that is 40-56% the length of the 4th ray, 17-18 gill rakers on the outer surface of the first gill arch, a U-shaped interorbital and a narrow slit-like postorbital trench, a low, median fleshy ridge extending half-way towards the orbit from the origin of the first dorsal fin, and, when freshly collected, a pink head and body with most body scales having an orange-brown spot or short bar at their centres. The species is currently known only from off Suva Harbour, Viti Levu, Fiji. Trimma finistrinum n. sp. has a bony interorbital equal to the pupil diameter, a fully scaled nape of 12-14 scales, a second dorsal spine that may reach posteriorly to the middle of the second dorsal fin, the papillae in the longitudinal row immediately below the eye either single or with two papillae in a vertical row, unbranched pectoral fin rays, usually a branched fifth pelvic-fin ray that is about half length of the fourth ray, and a large diffuse dark blotch on the posterior part of the caudal peduncle. A colour pattern of a brownish body with most body scales having golden- to greenish-yellow (pale in preservative) centres is unique among species of the genus. The species is currently recorded only from off the north and east coasts of Viti Levu, Fiji.

傾斜平面上に等間隔配置された水平加熱円柱列まわりに生じる自然対流の流動と伝熱

The natural convective flow and heat transfer of air induced around an inclined row of heated horizontal cylinders have been investigated experimentally. The experiments were carried out with the ten-cylinders row placed in the plane of inclination angles θ=0°, 30°, 45°, 60°, 75° and 90° from horizontal. The cylinders in the row were heated with constant heat flux and their diameter d and gap G were varied as d=8.4, 14.4mm and G=3.6 to 20.6mm. The Nusselt numbers Nud from the cylinders in the row were measured. They showed maxima and minima for the horizontal and vertical rows, while intermediate Nusselt numbers were obtained for the inclined rows. Those Nusselt numbers were next converted to the gap-based Nusselt numbers NuG, and, then, rearranged with the non-dimensional parameter RaG*(G/d). The result showed that the Nusselt numbers NuG are predicted well with the parameter RaG*(G/d) for the whole rows of inclination angle from horizontal to vertical.

Anatomically preserved "strobili" and leaves from the Permian of China (Dorsalistachyaceae, fam. nov.) broaden knowledge of Noeggerathiales and constrain their possible taxonomic affinities.

Noeggerathiales are an extinct group of heterosporous shrubs and trees that were widespread and diverse during the Pennsylvanian-Permian Epochs (323-252 Ma) but are of controversial taxonomic affinity. Groups proposed as close relatives include leptosporangiate ferns, sphenopsids, progymnosperms, or the extant eusporangiate fern Tmesipteris. Previously identified noeggerathialeans lacked anatomical preservation, limiting taxonomic comparisons to their external morphology and spore structure. We here document from the upper Permian of China the first anatomically preserved noeggerathialeans, which enhance the perceived distinctiveness of the group and better indicate its systematic affinity. We describe in detail the newly discovered, anatomically preserved heterosporous strobilus Dorsalistachya quadrisegmentorum, gen. et sp. nov., and redescribe its suspected foliar correlate, the pinnate leaf Plagiozamites oblongifolius. Plagiozamites possesses an omega (Ω)-shaped vascular trace and prominent cortical secretory cavities-a distinctive anatomical organization that is echoed in the newly discovered strobili. Dorsalistachya strobili bear highly dissected sporophylls alternately in two vertical rows, suggesting that they are homologs of leaf pinnae. If so, the "strobilus" is strictly a pseudostrobilus and consists of sporangium-bearing units that are one hierarchical level below true sporophylls. The "sporophylls" bear four microsporangia on the lower (abaxial) surface, occasionally interspersed with short longitudinal rows of megasporangia. A single functional megaspore develops within each winged megasporangium, suggesting adaptation for dispersal as a single unit. Dorsalistachya presents a unique combination of reproductive features that amply justifies establishment of a new family, Dorsalistachyaceae. Noeggerathiales represent a distinct taxonomic Order of free-sporing plants that most resembles early-divergent eusporangiate ferns and the more derived among the extinct progymnosperms. By the early Permian, noeggerathialeans had attained levels of reproductive sophistication similar to the most derived among the Paleozoic sphenophytes and lycophytes, but their heterosporous life history may have contributed to their extinction during the Triassic climatic aridification.

Effect Double Vertical Batteries Storage on Hydrogen Concentration in Air Conditioned Storage Room

Indoor air quality inside NiCad battery storage rooms is investigated in the current research. A proper ventilation system will guarantee safe environment inside the battery room by keeping vented gasses within their safe threshold allowed by standards and achieve sustainable energy efficient design by selecting the proper value of Air change per hour (ACH). This should be done by selecting the optimum configuration of inlets and outlets grilles location as well as choosing the most suitable way of battery storage whether on single rack, double rack or double rack with multi steps. Indoor air quality inside the battery storage room subjected to hydrogen gas emissions from the stored vented batteries is investigated numerically throughout the current research using Computational Fluid Dynamics (CFD). ANSYS 16.0 software was used. Parametric study is done to investigate the effect of splitting the long single row into two halves vertical rows (double rack with single step and double rack with double step) on ventilation efficiency for safety considerations. Storing the batteries in double vertical racks with double steps offered the best ventilation performance, using wall type inlet grille at the lower wall section (at the side) and outlet grilles at the roof, while the batteries’ racks are surrounded by curtains to act as local exhaust ventilation technique.

First Report of the Morphology and rDNA Sequences of Two Pseudopolydora Species (Annelida: Spionidae) from Japan.

The morphology of two Pseudopolydora species, P. cf. reticulata Radashevsky and Hsieh, 2000 and P. achaeta Radashevsky and Hsieh, 2000 are reported from Japan for the first time. Pseudopolydora cf. reticulata was collected from Japanese tidal flats, and individuals possess the characteristic netlike pigmentation on the dorsum of anterior chaetigers and the longitudinal black band along midline of caruncle. Pseudopolydora achaeta was collected from subtidal bottom mud of Onagawa Bay, and individuals have distinctive characteristics, such as intensive black pigmentation on dorsal and ventral sides of the anterior body and nearly straight vertical rows of major spines on the fifth chaetiger. The morphology of P. cf. reticulata is very similar to that of P. cf. kempi, with which it had been confused in Japan. We analyzed the 18S and 28S rRNA gene sequences of all five Pseudopolydora species recorded from Japan and found strong evidence that they are genetically distinct. Our analysis also suggests that boring polydorids have evolved among non-boring ones; the genus Pseudopolydora, which mostly shows the non-boring form, appears to have remained in a more ancestral condition.

Numerical simulation of directional propagation of hydraulic fracture guided by vertical multi-radial boreholes

The conventional hydraulic fracturing is not effective in the target oil development zone (remaining oil or gas, trap reservoir, etc.) with available wellbores located in the azimuth of non-maximum horizontal in-situ stress. The technology of directional propagation of hydraulic fracture guided by vertical multi-radial boreholes was innovatively developed. In order to verify the technology, a 3D extended finite element numerical model of hydraulic fracturing promoted by vertical multi-radial boreholes was established using Abaqus Software, and the influence of horizontal in-situ stress differences, azimuth, diameters, spacing, and lengths of radial boreholes, rates and viscosities of fracturing fluids, Young modulus and Poisson's ratio of rock, and reservoir permeability on propagation of hydraulic fracture guided by radial borehole row were comprehensively analyzed. Moreover, the term ‘Guidance factor (G)’ was introduced for the first time to effectively quantify guidance of radial borehole row. Finally, the guidance of the above ten factors is comprehensively evaluated through gray correlation analysis. The results showed that the directional propagation of hydraulic fracture is realized through scientifically arranged vertical radial borehole row, and ‘G’ reflects the real guidance strength of radial borehole row to hydraulic fracture. The azimuth of radial borehole row increases by 75°, G increases by 18 times. Horizontal in-situ stress difference increases by 9 MPa, G increases by 95%. The borehole diameter increases by 4 cm, G decreases by 54%. The borehole spacing increases by 0.5 m, G increases by 18%. The borehole length increases by 10 m, G decreases by 40%. Young's modulus of reservoir rock increases by 20 GPa, G decreases by 23%. Poisson's ratio increases by 0.1, G increases by 57%. Permeability of reservoir increases by 100 times, G increases by 3.3 times. Injection rate increases by 9 m3/min, G decreases by 63%. Both excessively high and low viscosities are adverse to guidance of radial borehole to hydraulic fracture, and 50 mPa s fracturing fluid creates best guidance to propagation of hydraulic fracture. The gray correlation analysis showed that the influences (from strong to weak) of the above factors on guidance of radial borehole were listed as follows: azimuth of radial borehole > injection rate of fracturing fluid > horizontal in-situ stress differences > Young's modulus of rock > viscosity of fracturing fluid > borehole diameter of radial borehole > radial borehole spacing > reservoir permeability > length of radial borehole > Poisson's ratio. This study provided theoretical evidence for directional propagation of hydraulic fracture promoted by radial borehole, and it predicted the guidance of radial borehole to hydraulic fracture in a certain extent, which is helpful for planning well-completion and fracturing operation in technology of hydraulic fracturing promoted by radial borehole.

Experimental study of falling film evaporation heat transfer on superhydrophilic horizontal-tubes at low spray density

This paper presents a series of experiments concerning heat transfer in a vertical row of horizontal-tube falling film evaporator. By visualization and heat transfer experiments, the effects of hydrophilic modification on the inter-tube flow patterns and evaporation heat transfer performance on different tubes, the superhydrophilic, hydrophilic and plain tubes, were investigated. The visualization results indicated that four flow patterns, droplet, droplet/jet, jet and jet/sheet mode was achieved in this study and the hydrophilic modification has little effect on flow mode transition. Experiments have been indicated that the superhydrophilic and hydrophilic tubes were completely wetted while the plain tubes were partially wetted at low spray density. The heat transfer results demonstrated that superhydrophilic tubes could maintain a high heat transfer coefficient at a wide range of flow rates (Res from 60 to 700). While, high enhancement was achieved at low spray density, at which the plain tube was not be wetted. When Res reached 350, three surfaces had the similar heat transfer performance. Simultaneously, the heating water inlet temperature had little effect on heat transfer coefficient for superhydrophilic tubes and had a negative influence on plain tubes and hydrophilic tubes at low spray density.

Palaeomacrosemius thiollieri, gen. et sp. nov., a new Macrosemiidae (Neopterygii) from the Upper Jurassic of the Solnhofen Archipelago (Germany) and Cerin (France), with a revision of the genus Macrosemius

ABSTRACTWe describe Palaeomacrosemius thiollieri, gen. et sp. nov., a new genus of Macrosemiidae (Neopterygii: Ginglymodi), from the Upper Jurassic (late Kimmeridgian to early Tithonian) of the Solnhofen Archipelago (Germany) and Cerin (France). Palaeomacrosemius, gen. nov., is characterized primarily by the following features: presence of vertical scale rows that do not dichotomize dorsal to the lateral line (unlike members of the genus Macrosemius Agassiz); a long dorsal fin with 32–33 dorsal fin rays; and a smaller scale-free area immediately ventrolateral to the dorsal fin compared with Macrosemius. Small, hook-like spines located on the posterolateral border of the principal dorsal fin rays may have functioned in reproductive behavior. We also review the currently known species of Macrosemius (M. rostratus Agassiz and M. fourneti Thiollière) from the Upper Jurassic plattenkalk of southern Germany and Cerin, France. Macrosemius rostratus, which we here restrict to the German plattenkalk basins of Eichstätt and Solnhofen (Tithonian above the eigeltingense horizon), is mainly characterized by the presence of 37–39 dorsal fin rays, which are very long in adult specimens. Macrosemius fourneti is mainly characterized by the presence of 34–35 dorsal fin rays, which are broader in the posterior part of the fin. Although M. fourneti was previously known only from Cerin, France, we here describe it for the first time from the older plattenkalk of Brunn (southern Germany, late Kimmeridgian).Citation for this article: Ebert, M., J. A. Lane, and M. Kölbl-Ebert. 2016. Palaeomacrosemius thiollieri, gen. et sp. nov., a new Macrosemiidae (Neopterygii) from the Upper Jurassic of the Solnhofen Archipelago (Germany) and Cerin (France), with a revision of the genus Macrosemius. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2016.1196081.http://zoobank.org/urn:lsid:zoobank.org:pub:414EFC70-C0FC-4CE7-919C-20ACB28A709D

Diffusible hydrogen content in submerged arc welds of a S960 type steel

Abstract Hydrogen induced damage is a dangerous phenomenon affecting the weld quality with regard to construction service life even without visible indication. The determination of diffusible hydrogen in weld metal has been standardized at an international level in ISO 3690:2012. This international standard specifies the sampling and analytical procedure for the determination of diffusible hydrogen in martensitic, bainitic and ferritic steel weld metal which arises from the welding of such steels using arc welding processes with filler metal. In this study, S960QL steel is extensively used in the heavy transport, lifting and mining industry, where mobile or fixed structures have to carry high loads – often in safety critical situations. In order to sustain extreme characteristics of these high strength low alloy steels, it is a must to reduce the manufacturing defects. In the investigations presented in this paper, the influence of arc length on the weld metal hydrogen concentration was studied according to the ISO DIS 3690 in S960QL type steel with submerged arc welding. Measurement of the diffusible hydrogen was carried out by means of carrier gas hot extraction method. The weld seams with different arc length have similar chemical compositions. Maximum hardness values in the range of 410–425 HV1 were measured in the HAZ on both vertical and horizontal rows in welded structure with two mm wire diameter due to recrystallization condition. For four mm wire diameter, the hardness decreasing which is depending on the grain coarsening in the welded samples with two mm was not occurred in the weld seam-HAZ interface. The larger weld pool and the long arc length increased possibility of hydrogen pick-up and absorbing. Because of this reason, the diffusible hydrogen contents in the welded structure increased in accordance with the arc length.

Wintering of honey bee colonies in cylindrical nest cavities versus oblong box-hives in a North European climate

We compared the efficacy of wintering honey bee colonies in wooden cylinders and wooden oblong box hives. Five colonies in “cylinders” and three colonies in “box-hives” were compared over two winters. The cylinders were 450 mm high with an internal diameter of 280 mm. The oblong box hives were Estonian standard one-box long hives with a frame size of 414 × 277 mm. Eight vertical rows of thermistors were fixed along the inner walls of both cylinders and hives and temperatures were measured at about weekly intervals. Food consumption and bee mortality of colonies were also assessed. In the cylinders, the winter clusters remained close to their front walls and away from the back wall, especially in cold weather. It was considerably warmer by the inner walls of the cylinders than in the hives, especially in the lower part. The surface of warm area decreased with cold weather and increased at around 0 °C indicating contraction and expansion of the cluster, respectively. In the second half of winter, there was a larger warm area in the cylinders than in the hives indicating that the clusters touched the walls of the cylinder more, thereby reducing heat losses further. Considerably, less food (13.5%) was consumed in the cylinders than in the hives. The numbers of dead bees on the floor was significantly lower in the cylinders than in the hives, but total bee mortality (dead bees on the floor + bees flown out in winter) differed little between cylinders and hives.

Effects Of Drinking Seawater During A Resistance Training Program On Kidney, Performance And Cardiovascular Health

The oceans contain a vast amount of potential resources for pharmaceuticals and nutritional supplements. Recently, the most widely available component of the oceans, seawater (SW), has been incorporated into supplements designed to improve physical performance and overall health but the efficacy of this is currently unknown. PURPOSE: To analyze the effects of consuming a SW-based electrolyte drink during a resistance-training (RT) program on kidney health, physical performance, and cardiovascular risk in older adults. METHODS: 56 sedentary older adults (71.3±6.2 yr) were divided into three groups: control group (CG) (n=18) that continued normal activities without additional physical training or nutritional supplementation; placebo group (PG) (n=19) that drank a 20 ml sample of mineral water before and after each training session; and a SW group (SWG) (n=19) that consumed a 20 ml sample of electrolyte drink (Totum Sport) before and after each training session. A 12 wk RT program using elastic bands was performed on 2 d/wk with 6 exercises and 4 sets of 6 repetitions. Isometric strength for the upper (vertical row (VR)) and lower (horizontal leg press (HLP)) extremities, levels of creatinine and urea (kidney health indicators), and atherogenic index (AI) (cardiovascular health indicator) were assessed pre and post training. RESULTS: SWG significantly (p<0.05) improved VR (+44.6%) and HLP (+52.8%), significantly reduced urea levels (-6.6%) and AI (-4.9%), and showed a trend towards reducing creatinine levels (-5.4%). PG significantly improved VR (+29.3%) and HLP (+52.5%), and significantly reduced AI (-4.50%) with no changes in urea and creatinine values. There were no significant differences between the exercise groups. VR (+9.5%), urea (+5.4%), and creatinine (+1.3%) did not change in CG but there were significant changes in AI (+14.1%) and HLP (-24.7%). There was not an interaction between groups for VR, HLP, and AI, but there was for urea and creatinine levels with CG showing significant differences compared to the exercise groups. CONCLUSIONS: Drinking SW while involved with a RT program may improve kidney health, cardiovascular health, and IS in older adults.

Three new species of Laonice (Polychaete: Spionidae) from West and Southwest Africa.

Three new species of Laonice (Polychaete: Spionidae): L. galatheae, L. cricketae, L. olgae-are described from South and West Africa (along the coast from 31°14.1'S to 04°44'N) based on Danish and South African zoological collections. Arguments relative to the morphological heterogeneity of the genus Laonice are advanced. The arguments are based on the following characters: degree of fusion of prostomium with peristomium at the anterior margin, degree of variability of all numerical characters, arrangement of anterior capillaries in two or more vertical rows, presence or absence of transversal dorsal membranous crests in the "post nuchal organ" and presence of genital pouches only on very limited number of segments or other pattern. Authors think it is obvious today an existence of at least four morphologically separate groups of species inside the Laonice-genus: "L. cirrata", "L. sarsi", "L. appelloefi" and "L. norgensis" groups. Eight species names from 34 valid names in the genus are still with unclear affiliation. L. quadridentata is treated now as a junior synonym of L. brevicornis. An opinion is expressed about L. insolita not belonging to the genus Laonice because of discrepancy the generic diagnosis.

The Five-Vertex Model and Enumerations of Plane Partitions

We consider the five-vertex model on an M ×2N lattice with fixed boundary conditions of special type. We discuss a determinantal formula for the partition function in application to description of various enumerations of N × N × (M − N) boxed plane partitions. It is shown that at the free-fermion point of the model, this formula reproduces the MacMahon formula for the number of boxed plane partitions, while for generic weights (outside the free-fermion point), it describes enumerations with the weight depending on the cumulative number of jumps along vertical (or horizontal) rows. Various representations for the partition function which describes such enumerations are obtained.

Особливості лісової типології в країнах Альпійсько-Карпатського макрорегіону

У загальноєвропейському масштабі тип лісу розуміють як категорію, визначену за складом деревної рослинності та умовами місця росту. Основою лісотипо­ло­гічної класифікації лісової рослинності у гірських країнах Європейського Союзу є природничо-лісова регіоналізація та рангування типів лісу за висотними ступенями рослинності у горах. Подальша диференціація лісового континууму пов'язується з особливостями геологічного підґрунтя, рівнями родючості ґрунтів, ступенями зволоженості та діапазонами її мінливості. Кожен тип лісу у межах конкретного регіону позначається формулою, що містить послідовний ряд абревіатур наведених категорій, який завершується шифром клімаксового лісового рослинного угруповання. Досягнення лісівничих шкіл сусідніх гірських країн у побудові схем системно-структурної диференціації лісового покриву та класифікацій типів лісу можуть слугувати прототипами, за якими варто було б здійснити комплексне удосконалення лісової типології Українських Карпат.&#x0D;

Fluid flow and heat transfer of natural convection induced around a vertical row of heated horizontal cylinders

Natural convective flow and heat transfer induced around a vertical row of heated horizontal cylinders were investigated experimentally. The experiments were carried out with the 10-cylinder rows of diameters d=8.4, 14.4, 20.4mm. The cylinder rows were placed in air with vertical gaps ranging from G=3.6mm to 150.6mm. These enabled the experiments in the wide ranges of the modified Rayleigh numbers 5×102<Rad∗<105, and the non-dimensional gaps (G/d)=0.176–17.9. The flow fields around the row were first visualized using a smoke. The results depicted that the plumes arising from the upstream cylinders remain laminar throughout the rows when the gaps between cylinders are smaller than 20.6mm. While when the gaps are larger than 30.6mm, the plumes begin to sway and undergo the turbulent transition on the halfway of the rows. The average heat transfer coefficients from the individual cylinders in the row were subsequently measured. They showed a monotonous decrease toward downstream when the flow remains laminar. While when the turbulent transition occurs, they turn to increase. The coefficients were next arranged with various parameters to obtain non-dimensional heat transfer correlations. Among those parameters, the parameter RaG∗ (G/d) was found to best correlate the present Nusselt numbers NuG, where, RaG∗ and NuG are the gap-based modified Rayleigh and the average Nusselt numbers. Moreover, the non-dimensional heat transfer correlations were proposed both for the laminar and turbulent flows based on the data plots in NuG–RaG∗ (G/d) plane. The proposed correlations are very simple but can predict the Nusselt numbers quite satisfactory.

Kongo: Power and Majesty

Kongo: Power and Majesty

SPINNING LED DISPLAYUSING RADIO FREQUENCY

The project consists of Spinning LED display using RF which displays the messages send by the user at the handheld device. if there are no inputs from the user for the system, the message that is programmed in the microcontroller will be displayed continuously. The circuit needs to be mounted on a mechanical structure that rotates at high speed. The display consists of 7 LEDs only in a vertical row. By moving them fast enough, message can be displayed which appears to be generated by a 7*n matrix of LEDs and not a single column of LEDs, where n is the no. of columns of the display matrix. This illusion is based on inertia of human eye or in other terms PERSISTANCE OF VISION. It consists of motor and seven LEDs that are arranged in a vertical line. The motor spins at a constant rate such that the LEDs rotate around a centre pivot point. As the LEDs spin around they light up sequentially such that they will display the message. The motor spinning fast enough that the human eye will perceive all of the display is on at once, and the viewer will be able to read the message completely. If LED formed message will periodically and frequently enough flash, they will appear solid and steady. A microcontroller is used to keep the message and blink the LEDs in an appropriate pattern. It has to be programmed so that it will both keep message and also send the appropriate signals to the LEDs to light them in the correct sequence.

Performance evaluation of tubular aluminum foam heat exchangers in single row arrays

Two sets of three tubular heat exchangers, constructed by wrapping aluminum foam of different thickness around cylindrical tubes, are being tested for heat transfer performance and pressure drop characteristics. Each set of heat exchangers is mounted such that it forms an array of a single, vertical row inside a low airflow wind tunnel. The tests are carried out under cross-flowing air velocity between 0.5 and 5.0 m/s at 0.5 m/s interval. The effects of foam thickness and transversal pitch distance are discussed and thermo-hydraulic results are benchmarking against those of a conventional finned tube array. It is found that within the designated range of airflow and the same level of compactness, the heat exchanger array with thicker foam layer enhances heat transfer 1.5 to 1.8 times compared with the one having thinner foam. In an array with fixed foam thickness, heat transfer improves at narrower pitches. At a discussion of the results, two empirical correlations to predict friction factor and thermal resistance are presented.