Pair Of Wings Research Articles

A new palaeodictyopteran Haseneura jarmilae gen. et sp. nov. from the Pennsylvanian of Piesberg reveals the structure of alinota

ABSTRACT A newly discovered palaeodictyopteran from the Pennsylvanian of Piesberg quarry (Lower Saxony, Germany) displays variability of wing venation on both wing pairs, well-preserved structure of thoracic nota and partially preserved wing base elements. Haseneura jarmilae gen. et sp. nov. is attributed to the family Archaemegaptilidae (Eugereonoidea) based on the wing venation characters, but several characters are also shared with representatives of Lycocercidae such as Apopappus Handlirsch, 1906. The preserved thoracic nota and wing bases demonstrate that wings were held in an outstretched position at rest, allowing to identify structural details. After the evaluation of venation characters across the superfamily Eugereonoidea and the re-examination of the holotype of Lithomantis meyeri Brauckmann et al., 2009 described from the same locality of Piesberg quarry, we propose transferring this species to Haseneura gen. nov. within the family Archaemegaptilidae as Haseneura meyeri comb. nov. zoobank: urn:lsid:zoobank.org:pub:D6839EFE-5AD0-4D89-9AD0-19BA0EF9580F

Combined manifestation of two geometric visual illusions.

The present study continued to investigate whether the effects of length misperception caused by cross-shaped (formed by two pairs of the oppositely oriented Müller-Lyer wings) contextual distractors can be explained by the combined manifestation of two different (i.e., the Müller-Lyer and filled-space) geometric illusions of extent. In psychophysical experiments, the luminance of one pair of wings was randomly changed, while the luminance of the other pair remained constant. Two different distractor orientations were used-when the wings with constant luminance formed the right side of the cross or the left side, otherwise. To separately evaluate the manifestation of the Müller-Lyer illusion under different luminance conditions, two distracting crosses of the same orientation were attached to the lateral stimulus terminators in the first series of experiments. In the following four series, a single distracting cross (with different orientation) was attached to one of the lateral stimulus terminators and various combinations of the constant and background luminance were used. To interpret the experimental data, we used the basic computational principles of previously developed quantitative models of hypothetical visual mechanisms underlying the emergence of the Müller-Lyer illusion and the filled-space illusion. It was shown that the results of theoretical calculations adequately approximate the experimental curves obtained for all modifications of stimuli, which strongly supports the suggestion that the joint manifestations of these two illusions can be considered among the main factors determining the features of the illusion investigated.

The working principles of canard wings and its aerodynamic advantages and effects on aircraft

Canard wings have gradually become more and more popular since the advent of the supersonic jet era, and research on the subject has become more detailed in order to be able to manoeuvre this pair of small wings more perfectly and effectively. This paper mainly studies the aerodynamic principle of the canard wings and the impact of its aerodynamic advantages on the efficacy and stealth performance of the aircraft under different aerodynamic stability and makes a comparative analysis with the horizontal tail. Through literature analysis and review as well as a small number of comparative analyses, this paper concludes that although canard wings can provide many aerodynamic advantages, they also have their limitations. Canards can only be effectively coupled when they are close to the main wing and longitudinally higher than or equal to the height of the main wings. The radar cross-section (RCS) characteristic of the canard wings will increase with the angle of its deflection.

An experimental study on attitude control of a tailless hummingbird-mimetic flapping-wing robot with defective wings

Hummingbirds demonstrate remarkable robustness to wing defects by maintaining stable hovering during the molting process. However, mimicking these capabilities in flapping-wing robots presents significant challenges. To investigate the effectiveness of various controllers in maintaining the attitude of a hummingbird-mimetic flapping-wing robot against external disturbances under different wing defects, this study implemented a PD controller, a PID controller, and a three-loop feedback controller with a disturbance observer (3L-DOB controller). The flapping-wing robot features a pair of wings and controls its body’s yaw, pitch, and roll rotations by modulating the tension of wing membranes and the neutral positions of wing torsion. The performance of these controllers was evaluated through semi-tethered experiments on a gimbal, employing three Wing Sets: intact wings, one wing was defective, and both wings were defective. The defective wing emulated hummingbird wing during molting, in which the wing area was cropped by 14.1%. As a result, the 3L-DOB controller showed the best performance in terms of responsiveness and accuracy across all Wing Sets, while the PID controller also achieved comparable performance.

A dragonfly-wings like self-powered magnetic field sensor with vibration noise restriction function

As the rapid development of the Internet of Things (IoT), the demand for the self-powered sensors and devices has become urgent. In this work, we present a self-powered magnetic field sensor based on a biomimetic dragonfly-wings like magnetoelectric (DWL-ME) laminated cantilever. The two pairs of wings in DWL-ME cantilever operating in anti-phase vibration modal has shown a strong magnetoelectric coupling for converting magnetic field energy into electric energy with an energy harvesting density of as high as 100 µWOe−2cm−3. It also shows a linear response to an alternating magnetic field (HAC) with a high detectability of 2.7 nT at 60 Hz. Compared to traditional cantilever beam ME sensors, its vibration noise is also effectively decreased by more than 30 dB due to the anti-phase vibration modal of two pairs of wings. The proposed biomimetic design strategy has inspirational significance for future sustainable, self-powered intelligent sensor networks.

Occurrence of Stenopoda spinulosa Giacchi, 1969 (Hemiptera, Reduviidae, Stenopodainae) in Brazil

The Reduviidae family is economically important, as many species are used in the biological control of agricultural pests. Many species in the Stenopodainae subfamily are endemic to tropical forests, and some smear their front paws with sticky plant-derived resin to help capture prey. The genus Stenopoda Laporte, 1833, has 14 species in Brazil. Stenopoda spinulosa Giacchi, 1969 (Reduviidae: Stenopodainae) has so far only been reported for the State of Rio Grande do Sul. They have wings that serve to protect the second pair of membranous wings and the body against crushing shocks. They are characterized by rigidity close to the notch of the wing and, at the same time, by the membranous region at the tip of the wing in the distal region. Their bite can cause edema, allergies, pain, and inflammation. To collect insects, a sweeping net or entomological net was used in shrubs and grasses. The objective of this study is to report the first occurrence of S. spinulosa in the State of Goiás, Brazil.

Aerodynamic performance of a flyable flapping wing rotor with dragonfly-like flexible wings

Drawing inspiration from insect flapping wings, a Flapping Wing Rotor (FWR) has been developed for Micro Aerial Vehicle (MAV) applications. The FWR features unique active flapping and passive rotary kinematics of motion to achieve a high lift coefficient and flight efficiency. This study thoroughly investigates the aerodynamic performance and design of a bio-inspired flexible wing for FWR-MAVs, emphasizing its novel backward-curved wingtip and variable spanwise stiffness resembling a dragonfly's wing. The research departs from previous aerodynamic studies of FWR, which focused predominantly on rectangular and rigid wings, and delves into wing flexibility. Employing Computational Fluid Dynamics (CFD), Computational Structural Dynamics (CSD), and experimental measurements, the study demonstrates the aerodynamic benefits of the dragonfly-inspired FWR wingtip shape and its reinforced structure. Fluid-Structure Interaction (FSI) analysis is used to examine the effects of elastic deformation encompassing twist and bending on aerodynamic forces. The results underscore the importance of bending deformation in enhancing lift and power efficiency and propose a method for analysing variable stiffness along the wingspan using a vortex delay mechanism that is induced by delayed flapping motion. By comparing modelled and measured stiffness, the study validates the flexibility of the FWR wing, revealing optimal aerodynamic efficiency is achieved through moderate flexibility and spanwise stiffness variation. The curving leading-edge beam forming the sweep-back wingtip offers a practical approach to obtaining variable stiffness and aerodynamic benefits for FWR-MAVs. Using the same pair of dragonfly-like flexible wings, FWR-MAVs have effectively exhibited VTOL and hovering flight capabilities, spanning from a 25-g single-motor drive model to a 51-g dual-motor drive model. This research provides valuable insights into flexible wing design for FWR-MAVs, leveraging biomimicry to improve flight efficiency.

USTButterfly: A Servo-Driven Biomimetic Robotic Butterfly

Different from birds, bats, flies, and other flying creatures that generate propulsions by flapping a pair of wings, butterflies with two pairs of wings have their peculiar flight aerodynamics. In this paper, a servo-driven biomimetic robotic butterfly, named USTButterfly, is designed to study the flight mechanism of biological butterflies. First, instead of using a single actuator to drive two pairs of wings, two servos are introduced to independently drive the left and right wings, thereby realizing tailless control of the robotic butterfly. Next, a bionic airfoil is designed inspired by the wing structure of the Glasswing butterfly. Wing geometry analysis indicates that USTButterfly well matches the morphological characteristics of biological butterflies. Finally, a multi-camera motion capture system is used to measure the flight characteristics of the robotic butterfly, and the results demonstrate that despite a larger Reynolds number, USTButterfly shares a similar coupled wing-bsody interaction with biological butterflies in the climbing flight. USTButterfly opens up a new way to study the flight specializations of biological butterflies, and offers a potential alternative paradigm for existing unmanned aerial vehicles.

Variasi Bentuk dan Warna Sisik Sayap Kupu-Kupu dan Ngengat

Butterflies and moths are members of Lepidoptera with the main characteristic of having two pairs of membranous wings covered with scales. The wings of butterflies and moths have colored patterns that can be used as protection from predators. The aim of this study was to compare the shape, size, and color variations of the scales on the wings of butterflies and moths. Samples of butterflies and moths were collected from the Dramaga Bogor Agricultural University campus. In this study, 11 species of butterflies were used belonging to three families, namely Pieridae, Nymphalidae, and Papilionidae, and 9 species of moths in four families, namely Erebidae, Geometridae, Hesperiidae, and Uraniidae. Observation of scales was carried out with a compound microscope connected to a camera, and measured using imageJ. The shape of the wing scales of butterflies and moths was elongated and widened with the base of the scales and the number of teeth on the distal part varied. The shape of the serrations on the butterfly scales tends to be rounded, while on the moth it is tapered. Larger scale sizes are found on light-colored butterfly scales and dark-colored moth scales.

Effect of α-cypermethrin and pirimiphos-methyl on wing morphology of Tribolium castaneum (Herbst) and T. confusum Jacquelin du Val: a comparative study

Tribolium castaneum (Herbst) and Tribolium confusum Jacquelin du Val (Coleoptera: Tenebrionidae) are widespread and serious pests of stored products. Various insecticides are applied aiming to effectively manage both species. Here, two insecticides are tested, the pyrethroid α-cypermethrin and the organophosphate pirimiphos-methyl, hypothesizing that they can lead to morphological changes in the certain body parts of the adult offspring of treated T. castaneum and T. confusum parental female adults. For this purpose, the geometric morphometric method to the elytra and hindwings was applied. Both males and females were included in the analysis. The results showed that adult individuals of T. confusum showed higher tolerance to both insecticides compared to T. castaneum adults. This finding is reflected in analyses of both pairs of wings in T. confusum where changes in shape were negligible. The hindwings of T. castaneum experienced deformations to both insecticides. More significant changes in wing shape were observed in the α-cypermethrin treatment compared to pirimiphos-methyl. In the case of T. castaneum, even the shortest exposure to insecticides (5 min) is enough to provoke shape changes in the hindwings. Deformities in offspring, caused after treatment of their parents with insecticides, could moderate the frequency of insecticidal applications in storages.

Numerical analysis and optimization of the heat transfer enhancement from the heat transfer fluid side in a shell-and-tube latent heat thermal energy storage unit: Application to buildings thermal comfort improvement

This study investigates the impact of enhancing the convective heat transfer on the Heat Transfer Fluid (HTF) side by passive flow manipulation on the melting and solidifying kinetics of a Phase Change Material (PCM) in a shell-and-tube Latent Heat Thermal Energy Storage (LHTES) unit. The PCM used is PureTemp 23 (PT23), a commercial bio-sourced product. The targeted application is the development of a LHTES unit for improving the thermal comfort in buildings through a combined heating and cooling approach. The study is carried out using the commercial code STARCCM+ and the enthalpy-porosity method, with appropriate implementation of the buoyancy source term. The numerical approach used for phase change modeling has been validated by comparisons with reference data from the open literature. Delta Wing pairs (DWg) and Delta Winglet pairs (DWt) vortex generators (VGs), were first inserted into the tube in which the HTF flows. Parametric analysis on the aspect ratio, position, and VGs number were performed, and optimization was done on the attack and rolling angles. The Performance Evaluation Criteria (PEC) index, which takes into account the heat transfer enhancement achieved and the related pressure losses, was used as an assessment criterion to evaluate the heat transfer augmentation of the studied enhanced tube with VGs. The results show that maxima can be reached for the different parametric studies carried out. While PEC increases with the attack angle until a maximum beyond which it decreases, it decreases consistently with the rolling angle. Once the enhanced optimal tube equipped with a shell containing the PCM, the results of the detailed study made on the kinetics for charging and discharging period of the enhanced LHTES unit reveal important gain for the storage unit. The heat transfer enhancement achieved result into more than 110 % increase in the PCM's melting/solidifying kinetics in the shell, thanks to an increase in the heat duty exchanged between the HTF and the PCM, leading to a considerable reduction of complete melting/solidification time. It was observed that the enhanced and optimized LHTES unit developed in the present study has a huge potential for improving buildings seasonal thermal comfort.

Computational evaluation of flight performance of flapping-wing nano air vehicles using hierarchical coupling of nonlinear dynamic and fluid-structure interaction analyses

This study endeavours to introduce an inventive hierarchical coupling methodology for evaluating the flight capabilities of polymer micromachined flapping-wing nano air vehicles (FWNAVs) using advanced computational tools. Furthermore, our objective is to provide a practical demonstration of FWNAVs in both tethered and airborne scenarios. These dual objectives represent the distinctive and pioneering aspects of this research. Such FWNAVs, which are insect-inspired robots, have a 2.5-dimensional structure. An FWNAV comprises a micro piezoelectric drive system and a pair of micro thin flexible wings. The drive system includes a micro transmission and a piezoelectric bimorph actuator. The flight performance of the designed FWNAV is evaluated using a hierarchical coupling approach, where the whole system is decomposed into a micro wing and a micro piezoelectric drive system. The coupling between these parts is modelled as one-way coupling and that between the micro wings and the surrounding air is modelled as strong coupling. In the one-way coupling analysis, nonlinear structural dynamic analysis is conducted for the micro piezoelectric drive system, where the dynamic response is transmitted to the micro wings via the Dirichlet boundary condition. In the strong coupling analysis, strongly coupled fluid-structure interaction analysis is conducted for the micro wings and the surrounding air to consider their strong coupling. The optimisation of flight performance is conducted using fluid-structure interaction analysis to achieve sufficient lift force to support the weight of an FWNAV. The design of a tethered and flyable FWNAV with a size of 10 mm or smaller is demonstrated. This FWNAV can be easily fabricated using polymer micromachining.

Feasibility study on mimicking the tail-beating supported gliding flight of flying fish

Mimicking the unpowered gliding capabilities of flying fish is challenging, due to the various technical limitations that are involved in creating a dual-modal robot that can both swim underwater and fly in the air. In this work, we suggest a modified KUFish design equipped with a pair of foldable wings for gliding flight in the air. Although the current water-leaping speed of the KUFish is lower than that of flying fish, the robot may be able to lift off by taking advantage of a head wind and forces produced by tail-beating motion, compensating for its weight, and overcoming the drag. Our series of computational fluid dynamics simulations has shown that with the unfolded wings and fully submerged tail-beating motion, when the wing and body angles are maintained in specific ranges under the head wind speeds of (9.5 and 6.5) m/s, the robotic fish after water-leaping can perform efficient gliding flight without generating pitching moment. This work can also be used to explain how flying fish perform gliding flight under tail-beating motion, and to develop an actual model of the dual-modal robot that mimics flying fish in the future.

Aerodynamic Exploration for Tandem Wings with Smooth or Corrugated Surfaces at Low Reynolds Number

Skin corrugation and tandem configuration are two distinct features that characterize the flow around dragonfly wings. In contrast to the smooth airfoil and single pair of wings of conventional airplanes, corrugated surfaces and tandem wings influence aerodynamics both locally and globally. In this article, several kinds of doubly- tandem wing configurations were designed, then computational investigations based on wind tunnel experiments were conducted to investigate the aerodynamic characteristics of these models. Computational simulations using in-house codes were carried out with a freestream velocity of 20 m/s at an angle of attack from −4° to 16°. Based on these computational results, the effects of airfoil thickness, surface waviness and hindwing decalage on aerodynamic characteristics were compared and presented quantitatively. Final results demonstrate that a tandem wing configuration could eliminate separation close to the trailing edge at angles of attack 8°~10°, or delay the trailing edge separation at angles of attack greater than 10°. Thus, the aerodynamic efficiency of tandem configurations could provide significant improvement compared to configurations with a single wing. The greatest percentage of aerodynamic efficiency improvement for a tandem thick configuration compared to a single thick configuration is 1376% at angle of attack 0°. Surface waviness will stall at a lower angle of attack, but will gain some aerodynamic benefit from the standing separated flow. Hindwing decalage has obvious lift enhancement for the tandem configuration. Therefore, it is concluded that the tandem configuration is attractive and promising for MAVs with flexible structures in the near future.

A First Exploration of the Archetypal Imagery of the Kylin

This paper explores the archetypal imagery of the Kylin in the Chinese psyche in the context of the cultural unconsciousness using the "multiple evidence method" of cultural anthropology and the "archetypal analysis" of analytical psychology. The Kylin archetypal imagery changes because the development of consciousness begins to have the ability to understand and confront the rich archetypal imagery of selfhood. The "deer" in a sense is a yin analog, That is, it becomes a symbol of power. Kylin has the body shape of a deer, and in Chinese characters, Kylin is written with a deer as a character component, so the element of deer occupies an indispensable place in the imagery of the Kylin prototype. Although the Horn of Kylin has the appearance of invasion and battle, it does not assume an attacking posture. Thus, the horn of Kylin is a symbol of the balanced unity of the two polarities of yin and yang. In addition, Kylin has the body of a deer, and its horn features both yin and yang qualities. From this perspective, the Kylin archetypal imagery is a combination of the two poles into one, which we can take as a symbol of integration, just like Tai Chi in Chinese culture. yang is summoned from the Self and yin is a link to the unconsciousness, a union of the ego and the Self in the unconsciousness, suggesting the sublimation of the oneness of Kylin's opposites. The Kylin has the body of a deer and a horn on its head, characteristics derived from mother earth's nourishment. The Kylin possesses a pair of wings that can link the transformation of the sky. Kylin is clad in scales, then it is the gift of water. It makes Kylin become the messenger who carries on the communication between consciousness and unconsciousness, plays the role of integration and linking, and becomes the bridge in the process of self-nature.

Morphological and molecular evidence of sandfly (Diptera: Psychodidae: Phlebotomine) and its relevance to recent cases of leishmaniasis from Jammu region of North India.

Present study was conducted to carry out morphological and molecular confirmation of sandflies collected at the Department of Parasitology, Faculty of Veterinary and Animal Sciences, R.S. Pura, Jammu, India. Larva was maggot like with large head, thorax and abdomen with typical black head, 12 abdominal segments and last abdominal segment carried two pairs of caudal bristles with matchstick hairs on each segment. The adult fly possessed head, abdomen and thorax. Head consisted of pair of long, hairy and beaded antenna, proboscis and one pair of prominent black eyes. Thorax possessed a pair of wings and three pairs of legs, wings were hairy and pointed with 2nd longitudinal vein branched twice. The abdominal segments were covered with small hairs and last abdominal segment was having a pair of anal recti. These identification characteristics confirmed the fly under study as Phlebotomus argentipes that confirms its occurance in this region. Molecular characterization of identified flies was carried out on positive morophological flies. Confirmation of Phlebotomus species was ascertained by amplifying the 18S ribosomal RNA gene sequence using PCR. Clear amplification was observed for Phlebotomus argentipes (538 bp). After sequencing/genotyping, Phlebotomus argentipes (OP646634) isolate of present study was clustering in same clade with Phlebotomus argentipes sequences obtained from GeneBank from other locations across globe, irrespective of their geographical location, thus providing the molecular evidence of this species present in Jammu region of North India.

Remythology and Ideology of Nyonya Muluk in Masmundari’s Damar Kurung Painting

This study aims to explore the visualization of damar kurung's painting with Nyonya Muluk theme and its meaning in the context of Javanese culture critically. It was stated that the figure of Nyonya Muluk was inspired by Masmundari's experience of meeting the Queen of the Netherlands who had visited Surabaya. Nyonya Muluk is described as a large woman who wears a dress and jewelery and has a pair of wings. Around her are other human figures painted in smaller sizes. To pursue the aim this study, the analysis was conducted using Gillian Rose's visual methodology which takes the position of the site of self. The analysis of this study found how Masmundari depicts objects by combining opposing cultural elements reflecting that the postcolonial subject is never completely the position of the colonized or the colonizing self. The ambivalence that arises in the practice of mutual views shows a form of negotiation or resistance from the colonized position. Masmundari's remitology also depicts the Indonesian nation as a colonized party trying to decolonize itself from colonial rule. By relocating the mythology of Nyonya Muluk in a contemporary context, this painting shows the efforts of the Indonesian people to regain 'independence' by using local traditions to fight against the culture imposed by the colonialists. In short, it can be concluded that the remitology of Nyonya Muluk in amar kurung's painting not only reflects Masmundari's resistance to Western colonial and post-colonial rule, but also represents Masmundari's resilience to the definition of her identity as Javanese.

The Barrette

The Barrette Carling McManus (bio) She couldn't have known—her fingers brushing my forehead,pulling loose strands from my faceto fasten a plastic clasp, a butterfly,pressed hard against my skulluntil the loud snap sounded insideher bedroom where she eyed our familybefore church. "That's better," she'd sayto the mirror, palming my shoulders.We'd stand as if for a family photo,a mother with her eldest daughter,the bright barrette biting my scalp.No way she would have knownthat these insects scavenge saltfrom rancid animal skin and with rolled,forked tongues, suck nectar from fatflower heads, lick the acidic surfacesof polluted pools, flit in the air untillanding on a lizard's eyelid to drinkits tears. Of course she didn't know—not even the British book binderwho hand-stitched the first volumeof Butterflies and Moths understoodexactly how much nature affixeselegance to deviance, like a pairof wings folded in an open hinge. [End Page 13] Carling McManus Carling McManus is a queer poet whose work appears or is forthcoming in Meridian, Best New Poets, The Beloit Poetry Journal, and was selected as the Poetry Prizewinner in Carve Magazine's 2021 Prose & Poetry Contest. She is a two-time Rona Jaffe Foundation Scholar for the Bread Loaf Writers' Conference and a Community of Writers alum. Carling lives on a mountainside with her wife and two border collies in Mink Shoals, West Virginia. Copyright © 2022-2023 Pleiades and Pleiades Press

Flight or protection: the genes Ultrabithorax and apterous in the determination of membranous and sclerotized wings in insects.

Present-day pterygote insects have two pairs of wings, one in the mesothorax (T2), the other in the metathorax (T3), and both have diverged in structure and function in different groups. Studies in endopterygote and paraneopteran species have shown that the gene Ultrabithorax (Ubx) specifies the identity and wing structure in T3, whereas the gene apterous (ap) significantly contributes to forming modified T2 wings. We wondered whether these Ubx and ap mechanisms operate in the lineage of polyneopterans. To explore this possibility, we used the cockroach Blattella germanica (Polyneoptera and Blattodea), in which the T2 wings are sclerotized (tegmina), whereas those of the T3 are membranous. We found that Ubx determines the structure of T3 and the membranous wing, while ap significantly contributes to form the sclerotized T2 tegmina. These results along with the studies carried out on the beetle Tribolium castaneum by Tomoyasu and collaborators suggest that ap plays an important role in the sclerotization and melanization of the T2 wings in neopteran groups that have sclerotized forewings. In turn, the sclerotizing properties of ap demonstrated in beetles and cockroaches suggest that the origin of this function goes back to the emergence of Neoptera, in the mid Devonian.

Evaluation of multi-fractures geometry based on water hammer signals: A new comprehensive model and field application

Hydraulic fracturing is an important means to develop unconventional resources. Fracture diagnosis techniques have been emerged in recent years, which can evaluate hydraulic stimulated fractures after stimulation treatment. Fracture geometry evaluation is an important part of hydraulic fracturing diagnosis. The fracture geometry evaluation techniques based on water hammer signal has the advantages of high economic efficiency, easy implementation and high timeliness. Previously, a model that couples the wellbore and the fracture (RCI model) had been proposed, which could calculate the fracture geometry. However, this model was mainly based on the assumption of a single fracture with a pair of double wings, and there was no research on the calculation of the geometry of multi-fractures. In this paper, a new model for calculating the geometry of multi-fractures was proposed. First, a new factor, the stress interference between the various fractures, was considered in the model. Second, based on the conservation of the total volume of fractures, the rationality of the volume equivalent relationship of multiple fractures was proved. Third, a new method was proposed to allow the new factor to be added to the model reasonably base on volume conservation. Additionally, our model was validated with the model in the previously published research. The effect of different parameters (number of fractures, fracture spacing, fracture volume) on the water hammer was analyzed. At last, the fracture geometry evaluation of micro-seismic and our model in field cases were compared. This paper provides a new model for evaluating the geometric characteristics of multiple fractures of water hammer signals.