It is a lecture note for the course AA210A Fundamentals of. 8. In simple terms, streamlines and streaklines are like a snapshot of the flowfield whereas pathlines are time-history of the flow. (10. Streaklines show the path followed by a specific fluid particle as it moves through the fluid over a period of time. When density = 1, the domain is divided into a 30x30 grid. , 2020; De Laurentiis et al. Understand the definitions for streamlines, streaklines, and pathlines. The plume lasts for four hours. Streaklines. Their fluids laboratory has a nice water tunnel into which they can inject multicolored dye streaklines, so they decide to test a spinning baseball in the water tunnel as shown in the figure. 8. density linearly scales this grid. 0:00 Streamlines0:47 Eulerian Approach1:32 Pathlines and Lagra. Describe a flow field for which this is true. linewidthfloat or 2D array. Select images, with strain-field (background color) and streaklines superimposed, show development of flow with [bottom row, SA(17)] and without (top row, bare Al) long-chain SAMs. Particles at any point in space and time that originate from an inflow boundary are mapped back to a point in this texture. \%-50vector lines Question As a very light feather is carried about by air, time-lapse video captures the changing. Examples of streamlines around an airfoil (left) and a car (right) 2) A pathline is the actual path traveled by a given fluid particle. Streaklines highlight increasing asymmetry of the flow and formation of vortices at increasing angles of attack. }, { x, x min, x max }, { y, y min, y max }] generates plots of several vector fields. The sheet is realised with a negative lens. The following animation illustrates the differences between a streakline and a pathline. 98 MBFigure: Equation of motion of a fluid element on a streamline with taking into account the gravitation. Flow across the streak line is possible. r¢~v and @~v RESULTS AND DISCUSSION. + -. Similarity requires that they match both the Reynolds number and the Strouhal number between their model. 2). The streaklines near the heated wire indicate that the fluid near the heated wire flows towards the heated section of the wire with circulation. A similar pattern can be seen at much larger scale in the air flow in the wake of an island. They differ only when the flow changes with time, that is, when the flow is not steady. 1. What follows is a lightly edited transcription of the video. These lines can also be obtained mathematically for given velocity field of a fluid flow. When density = 1, the domain is divided into a 30x30 grid. 1 Flow Patterns: Streamlines, Pathlines, Streaklines 1) A streamline ð k T, o is a line that is everywhere tangent to the velocity vector at a given instant. The wind tunnel is an open circuit suction style wind tunnel capable of wind speeds up to 9 m/s. Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!) 8th Edition. This is a video that introcues basic concepts of fluid motion, using different visualizaton techniques extracted from a CFD simulation of particles flowing a. the flow is incompressible b. 6+2. 3. 4-32C Solution For each case we are to decide whether a. The solution we’re going to load is an unsteady solution of vortex shedding. Initially, near X = 0, the streaklines are what we expect, i. 1 Streamlines and Streaklines 18 3. The dye will move around and define a curve given by {x(t 0,t)}, the position of fluid elements that passed through x 0 at some time t 0, prior to the current time t. Civil Engineering questions and answers. However, the spatial extension of the. A visualization of three-dimensional steady flow around a sphere is created by taking an extended exposure photograph of the sphere submersed in flowing water with air bubbles. In symbols, this is written as. 物質導數可作為 連續介質力學 對 形變 的 歐拉. 2) p Δ A − ( p + ∂ p ∂ s Δ s) Δ A = − ∂ p ∂ s Δ s Δ A. In a separated flow the streamlines are separated from the surface. Dye steadily injected into the fluid at a fixed point extends along a streak line. t. A plume of steam leaves a smokestack at x=0 and y=0. What is the line connecting all particles at t=4 s (see figure below)? There are 3 steps to solve this one. The example we are going to use is an unsteady solution of vortex shedding. They are all equivalent for steady flows, but differ conceptually for unsteady flows. The static pressure is the operating pressure in the pipe, duct, or the environment, upstream to the pitot tube. The units of time correspond to the units of the vector field. Author: Kreith, Frank; Manglik, Raj M. Determine the motion of two-dimensional point vortices. Are we seeing streamlines, streaklines, pathlines, or. The differences between streamlines, streaklines, and pathlines are as follows: Streamlines represent the instantaneous direction of the flow at each point in a fluid at a given time. 2, which is to be released in the next few weeks. 3. Uniform flow, Sources, Sinks, Doublets Reading: Anderson 3. San Francisco Bar Waves. These can be thought of as “recording” the path. Similarity requires that they match both the Reynolds number and the Strouhal number between their. Are we seeing streamlines, streaklines, pathlines, or timelines? Explain. Each of these lines provides di↵erent information on the movement of fluid. The curves represent the streaklines for every tenth row and column. In the Lagrangian approach the velocity of a fluid particleExpert-verified. 5, and 4. A scalar function. Flow visualization is an approach focuses on methods to get information from the flow field datasets either in 2 or 3 dimensional. Martinez-AMORCO Pier Currents. Streaklines: Streaklines are the paths traced by particles that have passed through a specific point in the flow field at different times. Observations of wind streaklines over the Red Sea from the ERTS-1 imagery. Engineering; Mechanical Engineering; Mechanical Engineering questions and answers; Some students want to visualize flow over a spinning baseball. 6. Mechanical Engineering. Coordinates, reference frames, equations, functions,. Where the angular velocity, w is equal to pi, 0 < x < 5 m, - 1 m < y < 5 m and 0 < t < 2 s. Flow lines explained! Streamlines, Pathlines, Streaklines. The wind field is modeled to be the following for the next 4 days and the steam is assumed to advect with the wind field. True. Convert a volume flow rate of 3. 11 Three types of fluid element trajectories are defined: Streamlines, Pathlines, and Streaklines. Concepts for describing fluid flows: streamlines, particle paths, and streaklines. Civil Engineering questions and answers. Controls the closeness of streamlines. Each cell in the grid can have, at most, one traversing streamline. Streaktubes, with slice planes. t. 0 gal/min to mathrm {m}^3 / mathrm {s} m3/s. These streamlines form a tube that is impermeable since the walls of the tube are made up of streamlines, and there can be no flow normal to a streamline (by definition). Analyze the graph of each function. The room is heated by a heat pump so that the temperature. In other words the defining property of a fluid is the ease with which the fluid can be. One should always be reminded that streaklines do not correspond to streamlines in an unsteady flow. 3) Consider the visualization of flow over a 12∘ cone in Fig. Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!) 8th Edition. To understand streaklines, consider a fluid flow with an ink dye injected at a particular point. For different densities in each direction, use a tuple (density_x, density_y). This circulation near. It is a little confusing, but think of a river which gets dammed. Before it is dammed, the streamlines are straight downstream, after it is. Mechanical Engineering. 3. The drag force from the water on a bubble is given by. specifies a set of points at which streaklines originate. If minor losses are neglected, determine the flow rates in each pipe. 3 mph Angle = Assuming the plant is located at (x,y)=(0,0), plot to scale: a) the streaklines at the end of each day. 這些最初應用在潛艇和飛艇. For unsteady flows the streamlines may change shape with time. 6: Pathline. 3. 流線型的起源可以追溯到19世紀對自然生命的研究，以及對於魚、鳥等有機形態的效能的欣賞。. A streakline is a Lagrangian description. Streaklines are used in a laboratory setting to observe fluid particle as they pass through a common point. Examples of streamlines around an airfoil (left) and a car (right) 2) A pathline is the actual path traveled by a given fluid particle. The visualization is produced by colored fluid injected into water. 5 at y/δ* ≈ 0. What does pathline looks like?What does streaklines look like?What does streamlines look like?We would like to show you a description here but the site won’t allow us. Oakland Outer Harbor LB 3. Streamlines, streaklines and pathlines coincide when i. The rotation direction of the cone shapes the streaklines ingested into the boundary layers. P4–29C. This can be accomplished by injecting neutrally buoyant smoke in air, or dye in water. It is shown that, if a dye is injected from near the critical layer, the streaklines have an appearance of amplification and rolling as if to indicate that the flow develops into discrete vortices. The wind velocity (km/h) is v=10i-5j for the first 5 hours and v=5i for the next 5 hours. The rolling‐up of a streakline. 1 Flow Patterns: Streamlines, Pathlines, Streaklines 1) A streamline ð k T, o is a line that is everywhere tangent to the velocity vector at a given instant. The pathline is the actual path in space followed by a particle which is moved by the flow of the vector field. We are assuming that the smoke is neutrally buoyant in the air! Result. Their fluids laboratory has a nice water tunnel into which they can inject multicolored dye streaklines, so they decide to test a spinning baseball in the water tunnel (Fig. In this video I will show you how to add streamtraces to your plot. A streakline involves the motion of all the fluid. 25. A wind speed of approximately 2 m/s was used in this study. Another technique would be to instantly inject a line of dye across streamlines and observe how this line moves as time increases. Streakline. Want to see more mechanical engineering instructional videos? Visit the Cal Poly Pomona Mechanical Engineering Department's video library, ME Online: in time at which the observation is made. Dye steadily injected into the fluid at a fixed point extends along a streak line. A technique to display streaklines was developed by Rumpf and Becker [13]. where V is the volume and t is the elapsed time. related to the pressure field by theFinal answer. As the equations that govern the flow remain. Figure 2: Visualization of flow over a sphere. In other words, an image of the flow characterized by streamlines is like a snapshot of the flow at one moment in time. Streaklines are easy to generate experimentally. 6+0. t. 1. This 10-minute video tutorial will show you how to calculate streaklines, streamlines and particle paths using Tecplot 360. Flow lines explained! Streamlines, Pathlines, Streaklines. Pathlines are the trajectories that individual fluid particles follow. Streaklines are new to computer vision research. Communicate. Pathlines 3. Question: 2) Are we seeing streamlines, streaklines, pathlines, or timelines in the visualization of flow over a sphere in Fig. Understand the definitions for streamlines, streaklines, and pathlines. 56 m/s. 4: Definition sketch for derivation of the Bernoulli equation for incompressible inviscid flow. 4. Where streamlines crowd together, the fluid speed is relatively high; where they open out, the fluid is relatively still. But my results do not agree with the text. 4, 4. Expert-verified. In both cases, we move with the object and the flow proceeds. BUY. 2. 2. Intuitively, if we place multiple small balls into the water flow at the same position but at different time steps, the streakline is the path by connecting all the balls in the placement order. Is this a langrangian or eulerian measurement?, A flow field is defined as _ in the _ frame of reference when. Dye steadily injected into the fluid at a fixed point extends along a streakline. We also go over how to obtain them experimentally. Another application is to visualize the velocity profile of a boundary layer or a channel flow. As illustrated in Figure 1b , according to mass balance, the change in SSC of a depth-averaged fluid parcel as it travels downstream reflects exchange. pathlines d. Question. Are we seeing streamlines, streaklines, pathlines, or timelines? Explain. Euler's equation for inviscid motion: a relationship between fluid acceleration (convective and temporal) and pressure distribution. The PIV-measured effective strain field (ε) and streaklines (white lines), superimposed on the raw images, are shown. Fluid flows are classified in terms of streamlines, streaklines, and pathlines. We assume that condition ν (t) < 1 / t of Proposition 1 below is satisfied [we have λ = 1 for solutions and ] that. (20) Sketch for Question 6. P7-41E). Mechanical Engineering. 4: Definition sketch for derivation of the Bernoulli equation for incompressible inviscid flow. Name an application where timelines are more useful than streaklines. Streakline definition: A locus of points of all the fluid particles that have passed continuously through a particular spatial point in the past. Streaklines Timelines Refractive flow visualization techniques Surface flow visualization techniques Profile plots Vector plots Contour plots 4. The particle tracking literature is primarily concerned with problems where thestreak翻譯：痕跡, 條紋;條痕, 特點, （常指不好的）特點，個性特徵, 短期, 一陣好運；一陣黴運, 一陣子，一連串，一系列, 快速移動, （通常指沿直線）飛奔，疾馳, 裸奔, （在公共場所）裸奔, 痕跡。了解更多。The images taken for Re = 131 and Re = 1004 contain vertical streaklines, consistent with laminar flow and the associated parabolic velocity profile. Here is how to do it. streak: [noun] a line or mark of a different color or texture from the ground : stripe. 1 16 Medan kecepatan : , dimana kecepatan dalam (m/s); x dan y dalam meter; A = 0,3 s- 1 Tentukan: a) Persamaan stream line dalam bidang xy b) Streamline yang melewati titik (x 0, y 0, 0 ) = ( 2,8,0 ) c) Kecepatan partikel pada titik (x 0, y 0Streaklines - Continuously injecting a new particle at each time step, advecting all the existing particles and connect them together into a streakline b. First, we extract streaklines from a map of remotely sensed SSC (Figure 1a, see Section 2. a. Question Under all flow conditions, these lines only grow in length, but never wiggle. Courtesy ONERA. e. 4. The visualization is produced by colored fluid injected into water from ports on the underside of the wing. Consider the plane flow field, 𝑉 ⃗ = (1 𝑥+ 𝑡) 𝑖̂− {𝑦 (1 + 𝑡)}𝑗̂ Develop expressions for streamlines, pathlines, and streaklines throgh a point (a,b) = (1,1). Not yet a. Discussion Timelines differ from streamlines, streaklines, and pathlines even if the flow is steady. We extracted streaklines from remotely sensed SSC estimates, and quantified water fluxes and velocities based on the distance between them. Leaflet | Esri. With regard to flow visualization, streaklines are defined as the traces of a colored material. Streaklines are lines deposited in the flow during a time interval by continuous emission of a tracer from a fixed point. Pathlines are the trajectories that individual fluid particles follow. Normal smoke wire flow visualization uses a smoke wire to demonstrate the flow streaklines. pathlines d. 5)The streaklines are aligned vertically close to the fuselage. 5, and 1; a pathline at t=1 for a. A pathline is a path which a fluid particle traces. Expert Answer. Global techniques - Display the entire flow field in a single pictureDetailed examples of Streamline Plots including changing color, size, log axes, and more in MATLAB. Fluid Mechanics. For a flow which does not change with time, the streamline, streakline, and pathline are the same line. There are some topics in the video that go beyond what has been discussed in class, but even. The. 8. Streaklines A streakline is the locus of points of all the fluid particles that have passed continuously through a particular spatial point in the past. Streaklines and Their Applications 54 Streamline Coordinates 54 Questions 56 4 Basic Equations of Fluid Dynamics 57 4. The type of particles depends on the source of the smoke, but usually, you can smell or taste either the soot or some of the gasses. \%-50gridlines b. \%-50timelines b. Euler's equation for inviscid motion: a relationship between fluid acceleration (convective and temporal) and pressure distribution. Describe how streaklines and pathlines might be different from streamlines for each case. Streaklines are the loci of points of all the fluid particles that have passed continuously through a particular spatial point in the past. 3. The high-speed. Q = dV dt = d dt(Ax) = Adx dt = Av. Use this argument with any of the input argument combinations from the. D. Since the vector field is time dependent, the pathline, streamline and streaklines are different concepts, see Wikipedia. StreamPlot [ { { v x, v y }, { w x, w y },. • Streaklines: Streaklines are defined as the locus of the path from where all the particles havepassed through in the past. AA200b - Applied Aerodynamics II Lecture 9 be tubulent and they are nearly impossible to compute analytically, except for some very simple cases. t. Streaklines are traced out by neutrally buoyant marker fluid injected into a flow field from a fixed point in space. Eulerian and Lagrangian Approaches. They show the history of the flow at a particular point. ##### FIGURE P4–29C. Trajectories, also called path lines, trace the route traveled by an air parcel during a time interval. In fluid mechanics, fluid is defined on the basis of its behaviour under the application of external forces. It is an instantaneous position of fluids that have passed through a fixed point of the flow field. 1. Question: Question 4 (1 mark) To describe the path that a fluid will take, we can use different techniques: pathlines, streaklines, and streamlines. Original and local streamlines for the Jet dataset. 2. A particle of the marker fluid that is at point (x, y) at time t must have passed through the injection point ( x_ {0}, y_ {0} x0,y0) at some earlier instant t= au t = τ. Photo of the damaged Chernobyl reactor. FIGURE P4–28CVisualization of flow over a 15° delta wing at a 20° angle of attack at a Reynolds number of 20,000. One example of a pathline is the path defined by a balloon floating in the air. ), in General Aviation Aircraft Design, 2014. Mechanical Engineering questions and answers. Evolution of timelines initiated at 𝑦 = 1. Only the top half is shown since the flow is symmetric about the horizontal axis. density linearly scales this grid. Fluid can be divided into two parts: Newtonian and non-Newtonian fluid. In fluid mechanics, ‘flow’ is what we call a fluid’s tendency to deform. Problem 1: (25 points total, 5 points each) Answer the following questions. 4, no. 6+0. Tutorials are split in Self-directed Tutorials and Classroom Tutorials: Self-directed Tutorial ’s Section 1 to Section 5 provide an introduction to the ParaView software and its history, and exercises on how to use ParaView that cover basic usage, batch python scripting and visualizing large models. 1. You'll get a detailed solution from a subject matter expert that helps you learn core concepts. 79-94, 1975. The speed of the flow is constant over a 10 s period, but the flow direction is not constant. the flow is steady iv. 流線型的起源可以追溯到19世紀對自然生命的研究，以及對於魚、鳥等有機形態的效能的欣賞。. Consider the visualization of flow over a 12° cone in Fig. 1 / 4. Slightly away from the fuselage and near the rotor blades, pockets of low-velocity flow circulation are observed. Streakline concentrates on fluid particles that have gone through a fixed station or point. \%-50vector lines e. \%-50timelines c. Somers t March 1989 Abstract A 21-percent-thick, laminar-flow airfoil, the S809, for horizontal-axis wind-turbine applications, has beenFor years, the Office of the Registrar and other University of Montana administrators have been on the steady path to make it easier for students whose chosen name differs from their legal name, like trans students, to change their name on as many UM records as possible. A region bounded by streamlines is called a streamtube. For the toxic cloud release, one would be most interested in determining the streakline passing through the location of the damaged reactor. Their fluids laboratory has a nice water tunnel into winch they can inject multicolored dye streaklines, so they decide to test a spinning baseball in the water tunnel (Fig. Streaklines: particles are continuously introduced at a certain point, the streakline shows the line formed due to the release of these particles from the specific point. For mostunsteady flows this is not true. The visualization is produced by colored fluid injected into water from ports on the body. =1 . Streaklines and timelines align with the flow patterns in the background. streaklines b. 8xi+1. The laser is tuned sufficiently far from the center of the line, so that there is no excessive light absorption. Streamlines are useful for visualizing and understanding the overall flow pattern in a flow field. Location of The Tracer. Try 360, Fieldview, or RS with your own data and your own hardware. Fluid: The fluid is defined as the state of matter, which undergoes continuous deformation by the application of even the smallest shear force. pathlines d. Streamlines are easily generated mathematically while pathline and streaklines are obtained through experiments. \%-50vector lines What is the material derivative of mass? a. The color expression in the streamline plot indicates fluid velocity (in m/s). Here, it is achieved by translating the seed with the translational velocity and rotating it around the axis of rotation. Dampen the cotton swab with the water or alcohol (should be damp only – squeeze or blot out any excess). Streamlines, Streaklines, Pathlines, and Timelines. Explain. (Top) With bare Al workpiece, the shearing results in sinuous flow with thick-chip, wavy streaklines, and heterogeneous straining. Streaklines: Streaklines are the loci of points of all the fluid particles that have passed continuously through a particular spatial point in the past. Series of seed point was placed on a (a) line integral convolution (LIC) imageThat's actually not the definition of a streamline, and it is only true in a steady flow. 1 - Streamlines, Streaklines, and Pathlines 1) At time t 0, a dye streak was started at point A in a flow field of liquid. Pathlines are unique to each particle and do not cross, providing a clear trajectory for each. Eulerian and Lagrangian Approaches. Streaklines, Streamlines, and Particle Paths Duration 10:11. In this segment, we cover streamline (including deriving streamline equation), streakline, and pathline. Draw the direction of flow on the streamlines, streaklines, and pathlines. 1 Physical properties of materials; what distinguishes fluids from solids. \%-50gridlines e. , { x, y } ∈ reg] takes the variables {. 0) crashes and gives the segmentation fault. Just below this table further describes the difference between streaklines. Final answer. 2. Such flow may actually flow upstream, against the direction of the free stream airflow. 7. Additionally, a methodology for quantifying the unsteady advective transport between the two fluids using streaklines is presented and verified numerically for the same two examples. . Draw examples of a pathline, a streamline, and a streakline around the skier. 2. 3. Red and yellow colors represent the different directions of motion. Photo from. Interestingly, these nourishment patterns appear (at least qualitatively) identical to prior observations of biogenic streaklines visible in optical and SAR imagery (Ayoub et al. related to rate of strain by the dynamic viscosity ii. t. 11 B. \%-50vector lines e. time: specifies a set of times at which streaklines begin to be traced. 1–4. The study area subscene. 、脉线和流线 迹线（Pathlines）：某一流体质点的运动轨迹。 脉线（Streaklines）：关注空间某一位置，在经历较短的时间后，可以标识出流动过程中经过该空间点的许多流体质点，所有这些流体质点都在一定的时间内，先后流经这个固定的空间位置，连接这些流体质点的线。Civil Engineering. Some students want to visualize flow over a spinning baseball. Pathlines and streaklines provide ways to visualize flows. 3. 0) crashes and gives the segmentation fault. "the trajectories that individual fluid particles follow. 5, where δ*is the displacement thickness, show the subharmonic sinuous nature (Schoppa and Hussain, 2002 and Das Gupta and Roy, 2017) for all the cases. Southampton Shoal Channel LB 6. Tutorial - Illustration of Streamlines, Streaklines and Pathlines of a Velocity Field. Streaklines. Day 1 2 mph = 45 deg. Streaklines A streakline is the locus of points of all the fluid particles that have passed continuously through a particular spatial point in the past. The shear stress in a Newtonian fluid is i. If the flow is steady, nothing at a fixed point (including the velocity. generates a stream plot of the vector field { v x, v y } as a function of x and y. Streaklines can be seen as a special case of material lines. Assuming the plant is located at (x,y)= (0,0), plot to scale: a) the streaklines at the end of each day. Consequently, for every moment in time, we could visualize constructing any number of lines that would fill the whole field of. Simulations of streaklines in a cross-channel mixer and a perturbed Kirchhoff elliptic vortex are quantitatively compared to the theoretical results. ) a. It discusses the conservation of mass, momentum and energy, the types of fluid flow, the properties of compressible and incompressible fluids, and some examples of fluid flow applications. svg 1,050 × 900; 109 KB Pathlines streaklines. Flow separates when the gradient dV/dz equals zero on the. CIRCULATION 31 velocity associated with second term is 1 2ω. 2 Flow visualization - Flow lines † Streamline: A line everywhere tangent to the °uid velocity ~v at a given instant (°ow snapshot). P4-31C. Streaklines are the most common flow pattern generated in a physical experiment. Streamlines represent the instantaneous direction of the wind and are drawn as unending lines that may converge or diverge from one another (following. Pathlines and Streaklines •For an unsteady fluid flow, if we release a particle in the fluid, we can track its position as a function of time. 4. Learn more about streamlines, streaklines, pathlines, vortex core tracking MATLAB Can someone help me correct my code for tracking centre of vortex and for plotting streamlines, streaklines and pathlines by creating the code and not using Matlab 'streamline' function. This resource contains information related to overview of lagrangian and eulerian descriptions. A streakline is a curved line formed by a string of fluid particles when passed through a cer. . Streaklines are the loci of points of all the fluid particles that have passed continuously through a particular spatial point in the past. A high-speed round air jet Streaklines are the loci of points of all the fluid particles that have passed continuously through a particular spatial point in the past. And they represent the velocity. \%-50gridlines c. flowvis_02 Page 3 of 3 A pathline is a line traced out by a particular fluid particle as it moves through space. The streaklines are made up of two parts, involving the primary stream (indicated by the black solid lines) from the conventional nozzle inlet and the secondary stream (denoted by the red solid lines) from the slot injector. Pathline and streaklines provide ways to visualize flows. These can be thought of as "recording" the path of a. At a Re = 1211, transitional flow was. vectorlines b. Coordinates are measured in meters. Streaklines Another form of visualization is a streakline. Figure 3. Examples of streamlines around an airfoil (left) and a car (right) 2) A pathline. Streaklines can also intersect themselves and other streaklines. • Timelines: timelines are formed when a line is drawn through the adjacent particles at anyinstantaneous point of time. However, often sequences of timelines (and streaklines) at different instants—being presented either in a single image. precalculus. Streaklines: instantaneous loci of all fluid particles that pass through a given point xo. At present, your best bet is to solve the streakline ODE in the Wikipedia. Solution. Their fluids laboratory has a nice water tunnel into which they can inject multicolored dye streaklines, so they decide to test a spinning baseball in the water tunnel as shown in the figure.