streaklines. 193) in my dissertation follows: R =d0[ x b d0 cosθ0 − a bC∗d − 1 C∗d W−1(−exp(−a/b) b)], R = d 0 [ x b d 0 cos θ 0 − a b C d ∗ − 1 C d ∗ W − 1 ( − exp ( − a / b) b. streaklines

 
 193) in my dissertation follows: R =d0[ x b d0 cosθ0 − a bC∗d − 1 C∗d W−1(−exp(−a/b) b)], R = d 0 [ x b d 0 cos θ 0 − a b C d ∗ − 1 C d ∗ W − 1 ( − exp ( − a / b) bstreaklines  The solution we’re going to load is an unsteady solution of vortex shedding

Streaklines and timelines are effective visualization techniques for depicting vortex shedding, vortex breakdown, and shock waves in unsteady flows. Mechanical Engineering questions and answers. Streaklines can be used to show the path taken by a fluid particle as it separates from the surface and then reattaches downstream. They differ only when the flow changes with time, that is, when the flow is not steady. A pathline is the. t. \%-50gridlines c. a. Fluid: The fluid is defined as the state of matter, which undergoes continuous deformation by the application of even the smallest shear force. 5. Use index notation to derive vector and tensor relations. Streaklines are lines connecting all fluid particles that pass through the same point in space. Leaflet | Esri. Chief Noter. They. 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. Problem 2. , 2020; Shaw et al. 2. Streaklines: Streaklines are the paths traced by particles that have passed through a specific point in the flow field at different times. It has already been explained that in unsteady or turbulent flows, particles introduced one after the other in time (at the same place) follow different. 4 Concept and Consequences of Continuous Flow For a °uid °ow to be continuous, we require that the velocity ~v(~x;t) be a flnite and con- tinuous function of ~x and t. 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. Pathlines are unique to each particle and do not cross, providing a clear trajectory for each. 4, 4. Engineering. 1. 1 Integral and Differential Approach 57 4. Where streamlines crowd together, the fluid speed is relatively high; where they open out, the fluid is relatively still. SECTION 4. Contents 1 The challenge of fluid mechanics is mainly the kinematics of fluid flow. Examples can be seen in aerial photographs of smoke plumes emitted from smokestacks, or volcanic ash clouds. P4-31C. Dye steadily injected into the fluid at a fixed point (as in dye tracing) extends along a streakline. In the context of computer vision, streaklines may be used in a similar way to transport information about a scene, and they are obtained by repeatedly initializing a fixed grid of particles at. 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. This problem has been solved! You'll get a detailed solution from a subject matter expert that helps you learn core concepts. Streaklines are generated by introducing air bubbles at evenly spaced points upstream of the field of view. If minor losses are neglected, determine the flow rates in each pipe. Under all flow conditions, these lines only grow in length, but never wiggle. A streakline is a Lagrangian description. But my results do not agree with the text. 物質導數可作為 連續介質力學 對 形變 的 歐拉. Visualization of streamlines for the original vector field in the left image yields. Figure 2: Visualization of flow over a sphere. The net force on the stream tube in the flow direction is then. A streakline involves the motion of all the fluid. It is easiest to visualize a streamline if we move along with the body (as opposed to moving with the flow). Engineering Mechanical Engineering Fluid Mechanics: Fundamentals and Applications Some students want to visualize flow over a spinning baseball. Streaklines Another form of visualization is a streakline. Streamlines, Streaklines, Pathlines [edit | edit source] If in a flow field a curve is drawn in such a way that the tangent to the curve at any point represents the velocity to that point. Module 4: Fluid KinematicsThis module i. Table 1. Some students want to visualize flow over a spinning baseball. Timelines are more useful than streaklines when the uniformity of a flow is to be visualized. We would like to show you a description here but the site won’t allow us. timeline翻译:(事件发生的)先后顺序表, (显示做某事所需时间或某事何时发生的)时间表, (社交媒体上的)时间轴。了解. Streaklines are computed for a shear flow, which is perturbed by two waves in the form of a fundamental and a subharmonic, with various combinations of the two. In other words, any material line that passes through a fixed. Day 4 Day 3 Day 2 7 mph 5 mph Angle = 45 deg. streaklines d. At present, your best bet is to solve the streakline ODE in the Wikipedia. =1 . 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. The 2-hour long experiment begins at 6:00 AM at. The time history of a marker particle may be found by solving the pathline. \%-50gridlines b. III), including experimental and. Gently clean the surface of the print head, removing any dried ink, dirt or fibers. So the stream function is constant over streamlines, but they are not technically the same- one is a field, the other is a family of curves. Figure (b) gives and example of streaklines in a video. Images are then recorded for further analysis. This segment discusses the differences between Streamline, Streakline, and Pathline for both steady and unsteady flow. Interestingly, these nourishment patterns appear (at least qualitatively) identical to prior observations of biogenic streaklines visible in optical and SAR imagery (Ayoub et al. Give examples of an unsteady flow and a steady flow. 流线,用来表征三维空间的速度场。在当流场随着时间改变的时候,即非稳定流动时,Streamlines, streaklines, and pathlines三个名词含义不同。. 500-mb vorticity is also termed vertical vorticity (the spin is in relation to a vertical axis). Streaklines, Streamlines, and Particle Paths Duration 10:11. Civil Engineering questions and answers. Streaklines eminating from a “source”, colored by the scalar data. The visualization is produced by a time expo- sure of air bubbles in water. Particles at any point in space and time that originate from an inflow boundary are mapped back to a point in this texture. 4. – All fluids satisfying the continuum assumption must have zero relative velocity at a solid surface (no-slip condition) and so most flows are inherently two or three dimensional. Are we seeing streamlines, streaklines, pathlines, or timelines? Explain. 1. 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. Mechanical Engineering questions and answers. c) Pathlines of two particles in an one-dimensional flow can intersect. The topics which may be deduced about the nature of a flowing fluid without referring to the dynamics of continuum are explored in this chapter. A) What is the difference between streamlines and streaklines? (Note; we did not have time to cover this difference in class, so you likely need to reference your book- see chapter 4) (2 pts) B) From which of Newton's fundamental laws of physics is the Bernoulli equation derived? (2. 1. Determine how vorticity is produced by various mechanisms. Red and yellow colors represent the different directions of motion. Concepts for describing fluid flows: streamlines, particle paths, and streaklines. 4. This is because when a particle on a streamline reaches a point, a 0, further on that streamline the equations governing the flow will send it in a certain direction x →. The text defines the method for plotting the streaklines this way. Streaklines and timelines align with the flow patterns in the background. 6: Pathline. P4. Flow development is. Cross-sectional areas of the streaklines are calculated at various points along flow to investigate morphological evolution. 3. Streaklines involve release particles at a defined interval. 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. It is the locus of particles that have passed sequentially through a prescribed path in the flow. 8x) +(1. The time history of a marker particle may be. T his text is an abbreviated version of standard thermodynamics, fluid mechanics , and heat transfer texts, covering topics that engineering students are most likely to need in their. , The velocity field of the form V=u(x,y,t)i+v(x,y,t)j is a two. Expert Answer. Question: 6. † Pathline: The trajectory of a given particle P in time. 3. This is used to visualise the flow. The trajectory of the particle as a function of time, $(x_p(t),y_p. The example we are going to use is an unsteady solution of vortex shedding. Streamlines, streaklines and pathlines are field lines in a fluid flow. 3 Acceleration Field and Material Derivative The acceleration of a fluid particle is the rate of change of its velocity. You can also single-click to add individual. Use this argument with any of the input argument combinations from the. In this video we look at the difference between pathline, streakline and streamli. Other required parameters should be assumed. One of the first visualizations of streaks in a laminar boundary layer was done by Mochizuki downstream of a hemispherical roughness element. let me First define all these lines. For two-dimensional flow the velocity components can be calculated in Cartesian coordinates by. In the Lagrangian approach the velocity of a fluid particleExpert-verified. The net force on the stream tube in the flow direction is then. Are we seeing streamlines, streaklines, pathlines, or timelines? Explain. The overall length of the prototype submarine is 2. zero d. We developed a method for extracting streaklines from remote-sensed SSC, and used the change in SSC along streaklines to reveal patterns of deposition and erosion in Wax Lake Delta, Louisiana. Here is how to do it. Two streak lines may intersect each other. Streaklines are valuable for studying how. 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 Similarity requires that they match both the Reynolds number and the Strouhal number between their. During the experiment dye is released continuously and floats are released every 30 minutes (called tracking drogues) to monitor the surface currents. Observations of wind streaklines over the Red Sea from the ERTS-1 imagery. (15pts, 5pts each) a) Consider the visualization of flow over a 12° cone in the figure. (10. Tutorial - Illustration of Streamlines, Streaklines and Pathlines of a Velocity Field. These. These problems have already given me 3 days sleepless nights. Shown here is the visualization of flow over a 15 delta wing at a 20° angle of attack at a Reynolds number of 20,000. 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. A pathline is the actual path traversed by a given (marked) fluid particle. Displays all PORTS stations for the specified region and the product types for each station. In order to observe streaklines within a fluid you will first have to mark the fluid in some way. Mechanical Engineering. 2) p Δ A − ( p + ∂ p ∂ s Δ s) Δ A = − ∂ p ∂ s Δ s Δ A. Location of The Tracer. At time t', the expression for pathlines is: x 0 = x ′ − 1 + \cost ′. A scalar function. Those generalized streaklines have been previously introduced by Wiebel et al. For that we will need to solve the full Navier-Stokes equations within the me geometry of the wind tunnel and model, to obtain the flow. Streaklines are traced out by neutrally buoyant marker fluid injected into a flow field from a fixed point in space. 4. Each of these lines provides di↵erent information on the movement of fluid. 3. The relation between pathlines and streamlines is simple, as the latter are projections of the corresponding pathlines on physical space, as shown in Fig. 4-32C Solution For each case we are to decide whether a. Streamlines, Streaklines, Pathlines, and Timelines. Streamlines cannot intersect with each other, they are always parallel. In this segment, we cover streamline (including deriving streamline equation), streakline, and pathline. 2 Streamtubes, Stream Surfaces, and the Stream Function 19 3. From mass conservation, we see that for a steady, one-dimensional flow, the mass-flow rate is constant. These animated gif images illustrate the differences between streamlines, streaklines, pathlines, and timelines. Pathlines are the trajectories that individual fluid particles follow. . Dye or smoke is used to mark the fluid particles to visualize the movement of fluid particles in the fluid flow. We would like to show you a description here but the site won’t allow us. 1. Colored fluid is injected through same (fixed) points, and the flow of these injected particles is thus transparent in water. FIGURE P4–28CVisualization of flow over a 15° delta wing at a 20° angle of attack at a Reynolds number of 20,000. A pathline is a path which a fluid particle traces. Streakline denotes the locus of all points that passed through a given point within a time interval. A stress on a fluid particle's. generates a stream plot of the vector field { v x, v y } as a function of x and y. 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. Pathlines are the trajectories that individual fluid particles follow. Currently, there is no functionality in matplotlib to plot streaklines. Note that t 0 will be different for each fluid particle on a given streakline. These flow lines are not only useful for flow visualization, but also supply means by which solutions to. b) Consider the visualization of ground vortex flow in the figure. Streaklines. 3. Civil Engineering questions and answers. At any particular instant, the velocity in the entire field of flow is the same. Continuity Equation When a fluid is in motion, it must move in such a way that mass is conserved. Describe a flow field for which this is true. Show the streaklines of the plume at t=5h and t=10h. (a) A streakline is a time exposed lfow path of an individual particle over some period of time (b) A streamline represents an instantaneous flow pattern at a given time (c) Fluid within a streamtube must remain there and cannot cross the boundary of a streamtube (d) Just like streaklines, streamtubes are a time integrated quantityFor a steady flow situation, the curve representing the pathlines, streamlines, and streaklines are all the same. It is a little confusing, but think of a river which gets dammed. b) Pathlines of two particles in an one-dimensional flow can never intersect if the two particles move along the same direction. The velocity field of a flow is described by V › = (4x)i › + (5y + 3) j › + (3t 2 )k › . The visualization is produced by colored fluid injected into water from ports on the body. See moreStreaklines. 5 Vorticity and Circulation 24 3. Are we seeing streamlines, streaklines, pathlines, or timelines? Explain. One should always be reminded that streaklines do not correspond to streamlines in an unsteady flow. A plume of steam leaves a smokestack at x=0 and y-0. linewidthfloat or 2D array. The pressure on the lateral. 11 B. Engineering. Dye steadily injected into the. Description. Plot: streamlines for x & y <2 for t=0, 0. gridlines C. (b) A visualization of the strealines for an example video. Streaklines can be defined as the locus of particles that have earlier passed through a prescribed point. It's a subtle but important difference. ISBN: 9781305387102. ISBN: 9781305387102. \%-50timelines b. The streamlines in this plot group show the instantaneous fluid velocity as water flows toward, through, and away from the bend. This technique illustrates the large-scale. A streamline ( ) is a line that is everywhere tangent to the velocity vector at a given instant. for more FREE video tutorials covering Fluid Mechanics. One can also record streaklines for an array or points by injecting 3. ME 363 - Fluid Mechanics Homework #11 Due Wednesday, April 16, 2008 Fall Semester 2008 1] A student team is to design a human-powered submarine for a design competition. Streaklines Timelines Refractive flow visualization techniques Surface flow visualization techniques Profile plots Vector plots Contour plots 4. The path a fluid particle takes through a flow is actually called a pathline. Problem 1: (25 points total, 5 points each) Answer the following questions. 001 in. Streamtraces use the UVW vector variables in your plot and can be added easily with just a click and drag using the Streamtrace tool. (A pathline is an integrated pattern. In steady flow, the fluid is in motion but the streamlines are fixed. In simple terms, streamlines and streaklines are like a snapshot of the flowfield whereas pathlines are time-history of the flow. For a flow which does not change. Codes to plot fluid pathlines and streaklines given an example. Streaklines. CIRCULATION 31 velocity associated with second term is 1 2ω. Dampen the cotton swab with the water or alcohol (should be damp only – squeeze or blot out any excess). Mechanical Engineering. pathlines Marked out of c. streamline(___,options) plots streamlines using the specified options, defined as a one- or two-element vector with the form step or [step maxvert], where step is the step size in data units for interpolating the vector data and maxvert is the maximum number of vertices in a streamline. The units of time correspond to the units of the vector field. Streaklines Another form of visualization is a streakline. 6+1. . The SI unit for flow rate is m 3 /s, but several other units for Q are in common use, such as liters per minute (L/min). 1 Flow Patterns: Streamlines, Pathlines, Streaklines. Related terms: Vortex; Velocity Vector; Flow Visualization; Tunnels; Flow Pattern; Pathlines; Vector Field; Velocity Field; Vorticity; Fluid Particle Experimentally, streaklines are relatively easy to record. 25. The streaklines were captured by a high-speed camera (Photron FASTCAM Mini AX100 type 200K-M-32 GB), with a frame rate of 1000 frames per second. Basically a differential pressure (d/p) flow meter, a pitot tube measures two pressures: the static and the total impact pressure. Find step-by-step Engineering solutions and your answer to the following textbook question: What is the definition of a timeline? How can time ones be produced in a water. Since the flow is steady, the streaklines are coincident with streamlines. 2 t j – 1. The lines created in this type of demonstration are streaklines. In this example, streaklines are simply horizontal lines. 10. Find step-by-step Engineering solutions and your answer to the following textbook question: Consider the visualization of flow over a sphere in the figure. Normal smoke wire flow visualization uses a smoke wire to demonstrate the flow streaklines. You'll get a detailed solution from a subject matter expert that helps you learn core concepts. The following animation illustrates the differences between a streakline and a pathline. 4 The Divergence of the Velocity and Green’s Theorem 23 3. Draw the direction of flow on the streamlines, streaklines, and pathlines. Pathlines show the path traced out by individual fluid particles over time. Practically, such sediment plumes can be understood as diffusing streaklines, i. Berikut ini pembahasan tentang aliran – aliran pada mekanika fluida. The velocity field of a flow is described by V › = (4x)i › + (5y + 3) j › + (3t 2 )k › . Dye is injected into the flowing water to visualize the flow pattern in the converging channel. 1. First, the flow lines embracing streamlines, pathlines, and streaklines are discussed. The streamed flow was illuminated by a laser sheet provided by a 532-nm 10 W CW laser. Question: Under all flow conditions, as time proceeds, these lines wiggle/flop around while one end is anchored to a fixed point in the flow field. P7-41E). The substance that has a tendency to flow is called as fluid. Streaklines are numerically obtained for a shear flow perturbed by an unamplifying traveling sinusoidal wave. Correct option with explanat. Discuss how you can tell from the streamline pattern whether the flow speed in a. Photo of the damaged Chernobyl reactor. 01106655, 0. , 2016), which appears to validate the hypothesis that θ ≈ 0 particles behave similarly to. streamline翻译:形状, 把…设计成流线型,使成流线型, 改善, (常通过简化办事程序)使(机构)效率更高;简化。了解更多。Are we seeing streamlines, streaklines, path lines, or timelines? Explain. Vorticity Basics. Similarity requires that they match both the Reynolds number and the Strouhal number between their model test and the actual baseball that moves through the air. Streamlines. 1–4. Design and Experimental Results for the S809 Airfoil Dan M. The figure above shows the computed streamlines around an airfoil and around a cylinder. BUY. Explain. The sheet is realised with a negative lens. In other words, place a particle at point p, and move the particle one time step with the flow. The high-speed. 016 Hydrodynamics Reading #3 Particle Pathlines: Trajectory of fluid particles (“more” lagrangian) flow kinematics: streamlines, pathlines, and streaklines. 2) p Δ A − ( p + ∂ p ∂ s Δ s) Δ A = − ∂ p ∂ s Δ s Δ A. 4 3. This type of flow results from uniform shear in the deformation. Other required parameters should be. 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. Similarity requires that they match. Pathlines are useful for understanding the movement of water in rivers or the behavior of particles in chemical reactions or industrial processes. These can be thought of as "recording" the path of a. For reference, I got these. 3sin (ωt)−0. Streaklines can also intersect themselves and other streaklines. Streaklines are identical to streamlines for steady flow. Are we seeing streamlines, streaklines, pathlines, or timelines? Explain. 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. We will eventually allow streaklines and particle paths to. Open ParaView. P7–44). Pathlines are the trajectories that individual fluid particles follow. In a streakline, the entire line is moved through the flow. Similarly, the velocity vector is the projection of. This Session for Practice Problems on Flow lines (Streamlines, Streaklines, and Pathlines) is a Part of the Problem Solving Series for the Introductory Fluid. For mostunsteady flows this is not true. Students are required to evaluate the visualization effects of streamlines, streaklines and pathlines based on following two-dimensional velocity field equation V = (uˉ,vˉ) = (0. Similarity requires that they match both the Reynolds number and the Strouhal number between their. 5, and 1; a pathline at t=1 for a. Streaklines through the shock produced by a cylinder. 4. San Francisco Bar Waves. Draw the direction of flow on the streamlines, streaklines, and pathlines. 5sin(ωt)− 0. The smoke identifies the air that has flowed past the top of the chimney and the dye identifies the water particles that have flowed past the end of the dye injection tube. 3. 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. Calculating streamlines, particle paths and streaklines in Tecplot 360 EX 2014 R2. 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. For the following list of situations, classify each as a 1-dimensional, 2-dimensional or 3dimensional flow. These are streaklines extbf{streaklines} streaklines. These animated gif images illustrate the differences between streamlines, streaklines, pathlines, and timelines. Question: Question 4 (1 mark) To describe the path that a fluid will take, we can use different techniques: pathlines, streaklines, and streamlines. 3. Dye steadily injected into the fluid at a fixed point extends along a streak line. Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!) 8th Edition. 3 Streaklines Instead of releasing a single particle at x 0 = (x 0,y 0,z 0) at t = t 0, say (case of particle path tracing), release a continuous stream of dye at that point. Are we seeing streamlines, streaklines, pathlines, or timelines?3. Consider the visualization of flow over a 12° cone in Fig. It has already been explained that in unsteady or turbulent flows, particles introduced one after the other in time (at the same place) follow different pathlines. Dye steadily injected into the fluid at a fixed point (as in dye tracing) extends along a streakline. Streaklines are easy to generate experimentally. 物質導數. The wind tunnel is an open circuit suction style wind tunnel capable of wind speeds up to 9 m/s. Similarity requires that they match both the. The three water filled tanks shown in figure below are connected by pipes as indicated. In a steady flow the streamline, pathline and streakline all coincide. 4 Quantifying viscosityflow streamlines, streaklines, and pathlines coincide; in unsteady flow they can be different. 2. In fluid mechanics, fluid is defined on the basis of its behaviour under the application of external forces. 2? The visualization is produced by time exposure of air bubbles in water. Chapter 4 • Differential Relations for a Fluid Particle. \%-50vector lines e. The differences between each technique cause misunderstanding to new. Remote Sensing of Environment, vol. No Slip Streamtraces in Tecplot 360 Duration 2:40. Leaflet | Esri. In this context, streaklines may be obtained by repeatedly initializing a grid of particles and moving all particles according to the optical flow, in the spirit of a Lagrangian fluid flow. In each case, all the vortices are located at the bottom of the recessed cavity. 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. San Francisco Bar Waves. 2 Continuity Equation 59 4. With regard to flow visualization, streaklines are defined as the traces of a colored material. The particles feel all forces that the flow feels, as they ARE the flow. related to rate of strain by the dynamic viscosity ii. This can be accomplished by injecting neutrally buoyant smoke in air, or dye in water. ) a. \%-50vector lines Question As a very light feather is carried about by air, time-lapse video captures the changing. Two types of effectsStreaklines are well known in flow visualization [3, 4] and fluid mechanics [5] as a tool for measurement and analysis of the flow. 4 (m/s). 1 Continuity Equation: Integral Form 59 4. Streaklines show the path history of fluid particles that have passed through a particular location. Streaklines are the loci of points of all the fluid particles that have passed continuously through a particular spatial point in the past. 3. This link, however, has been the most helpful in understanding how to derive the necessary equations. Streaklines are cre-ated by tracking individual particles of ‘numerical dye,’ released at a constant rate from X= 0. 3. An example of a streakline is the continuous line of smoke emitted by a chimney, which will have some curved shape if the wind has a time-varying direction. In this context, streaklines may be obtained by repeatedly initializing a grid of particles and moving all particles according to the optical flow, in the spirit of a Lagrangian fluid flow. The curve that is traced out as we follow the particle is called the pathline. 1. II), and the structures of incompressible flow are described in detail (Sec. Streaklines are the most common flow pattern generated in a physical experiment. Flow lines explained! Streamlines, Pathlines, Streaklines. For a flow which does not change with time, the streamline, streakline, and pathline are the same line. Similarity requires that they match both the Reynolds number and the Strouhal number between their model test and the actual baseball that moves through the air. This tube is called a streamtube. Chemical Engineering questions and answers. In smoke wire flow visualization, smoke streaklines are generated from oil droplets on a heating wire or injected from the outer smoke generator/container during the experiments. 0:00 Streamlines0:47 Eulerian Approach1:32 Pathlines and Lagra. Streaklines are the path a fluid drop will follow in the flow. Final answer.