Increase In Superficial Velocity Research Articles

Experimental study on flow patterns and pressure gradient of decaying swirling gas-liquid flow in a horizontal pipe

The utilization of swirling flow in multiphase flow devices is prevalent for purposes such as mixing, separation, stabilization, and heat transfer enhancement, primarily owing to its characteristic of inducing low-pressure drop. In the nuclear industry, for example, two-phase swirling flow is applied in the nuclear gas generator to improve gas quality. In this study, an experimental investigation was conducted on the decaying swirling flow of gas-liquid in a horizontal pipe equipped with a vane-type swirler. The flow patterns were visually examined, and the pressure gradients along the test pipe and across the swirler were measured. The findings suggest the presence of four distinct swirling flow patterns at the swirler outlet (z/D = 0), namely chain flow, swirling gas column flow, swirling intermittent flow, and swirling annular flow. Because of swirl decay, these swirling flows recover their original pattern approximately 70D downstream from the swirler, with the exception of the swirling gas column flow. The flow regime maps at z/D = 10, 40, 70 and 100 are proposed and the pattern-based pressure gradient characteristics are analyzed. It is shown that the pressure gradient rises as both gas superficial velocity (jg) and liquid superficial velocity (jl) increase. The largest pressure gradient occurs within the swirler section, while the lowest is found upstream of the swirler. Near the swirler outlet (z/D = 0–33), the pressure gradient is approximately 1.5–2.3 times higher than at z/D = 33–67. Further downstream, at z/D = 67–100, it is 2.2–3.5 times greater, depending on the flow patterns.

CFD–PBM coupled modeling of liquid–liquid interphase mass transfer behaviors inside the Kenics static mixer

Kenics static mixers (KSM) are commonly used in various industries for its excellent mass transfer performance. It is essential to systematically analyze the relationship between fluid parameters and mass transfer parameters to better understand the mass transfer behaviors between liquid–liquid phases and optimize the mass transfer efficiency of the KSM. In this work, a computational fluid dynamic–population balance model coupled method is utilized and three mass transfer models are compared and analyzed. Further simulations investigate the mass transfer behaviors inside the KSM under different superficial velocities, dispersed phase volume fractions, and aspect ratios. The results show that the increase of superficial velocity leads to the 2.23–14.15–fold increase of volumetric mass transfer coefficient and the 1.71–4.56–fold increase of mass transfer rate. What's more, increasing the dispersed phase volume fraction leads to the significant increase of 15.51 times in volumetric mass transfer coefficient and 34.92 times in mass transfer rate. Moreover, the increase of aspect ratio could result in the reduction of 4.19–1.72 times in volumetric mass transfer coefficient and 1.81–1.17 times in mass transfer rate. This work provides valuable theoretical insights for the optimal design of the KSM and the enhancement of mass transfer performance.

Flow behavior and characteristic parameters of droplets in counter-current mini-channel extractor

Achieving the counter-current flow in mini-channel extractor is a challenge. The formation and characteristic parameters of droplets in mini-channel counter-current extractor were systematically investigated to provide a guide for the realization and operation of counter-current extraction. A mixture of P507 diluted with sulfonated kerosene was served as dispersed phase, while 0.2 mol/L LaCl3 solution was used as continuous phase. Droplets rapidly deformed from the nearly-spherical shape to ellipsoidal shape after detaching from nozzles, eventually floated upwards as monodisperse droplets with same spacing. Sauter mean diameter of droplets decreased with the increase of superficial velocity of organic phase, yet increased with the increase of superficial velocity of aqueous phase. The specific interfacial area of droplets increased with the increasing superficial velocity of organic phase, and slightly decreased with the increasing superficial velocity of aqueous phase. The correlations of droplet characteristic parameters were established using dimensional analysis for further prediction and analysis.

Gas-liquid mass transfer in microbubble column reactors

Microbubble column reactors (MBCRs) present great potential in gas-liquid reactions due to their superior mass transfer efficiency. In this work, an automated platform was built to investigate the effect of gas/liquid superficial velocity, and liquid viscosity on mass transfer performance. Compared to conventional bubble column reactors, MBCRs exhibit significantly enhanced mass transfer efficiency. The findings show that kLa initially increases, followed by a subsequent decrease with the increase of gas superficial velocity. This behavior is attributed to transitioning from a homogeneous to a heterogeneous regime as gas superficial velocity increases. The liquid viscosity has a dual effect on kLa within a homogeneous regime. However, the kL in MBCRs is smaller than that in conventional bubble column reactors due to the movement of large bubbles enhancing liquid turbulence. Moreover, a dimensionless correlation was developed integrating the Weber number to predict the mass transfer coefficient.

Inhomogeneous temperature in high temperature fluidized beds

In this work, we observe an inhomogeneous temperature distribution within a fluidized bed affects the mixing dynamics and therefore heat transfer performance. High temperature fluidized bed experiments with an initial temperature gradient are performed. As the superficial velocity increases, the bed becomes lightly fluidized. Despite fluidization, the bed temperatures do not converge, and the thermal gradients remain. Eventually the superficial velocity is sufficiently high to completely mix the bed and collapse the bed temperatures together. CFD-DEM coupled simulations are performed to investigate the mixing dynamics. Initial bed temperature differences of 100, 300, and 500 K are simulated with varying superficial velocities to create a regime map. At relatively low superficial velocities, the high temperature regions of the bed begin to bubble before the lower temperature regions due to gas density changes. To fully mix the particle temperatures in the vertical direction, the relative velocity (U/Umf) must be a minimum of 1.30.

A proposed method of bubble absorption-based deep dehumidification using the ionic liquid for low-humidity industrial environments with experimental performance

Liquid desiccant deep dehumidification (LDDD) is an excellent way to achieve low-carbon transformation of low-humidity industrial buildings. Currently, it is essential to improve its ability to produce lower humidity air (i.e., with a dew point below −10 °C). Functional ionic liquids (ILs) with extremely low vapor pressure, non-crystallization, and non-corrosion are ideal substitutes for high mass fraction aqueous inorganic solutions (e.g., LiCl, LiBr) in traditional liquid desiccant deep dehumidification. Meanwhile, the bubble absorption mode allows water vapor to condense on the huge contact surface between the bubbles and desiccant. Accordingly, it is expected to solve the low wettability and transfer unit number (NTUm) in falling-film absorption mode caused by the high viscosity of ILs. Thus, a new method of bubble absorption-based deep dehumidification using the IL is proposed. To validate it, the bubble absorption-based deep dehumidifier using a novel ionic liquid (BADD-IL) is developed and tested under different operating conditions. Besides, its moisture effectiveness is compared with those of falling film absorption-based dehumidifiers. The results show that increasing the liquid height, superficial velocity, as well as lowering the solution temperature, can strengthen the deep dehumidification performance, effectiveness and cooling ability to varying degrees. The increase of liquid height and superficial velocity promotes the gas-liquid interfacial area from different aspects, thus enhancing the transfer efficiency. Notably, the insufficient interfacial areas caused by low solution temperature cannot prevent better transfer efficiency dominated by high potential difference. Moreover, the NTUm of BADD-IL has a wide adjustment range (0.1–1.7), and the minimum supply air humidity ratio and maximum moisture effectiveness can reach 1.1 g/kgda and 81%, respectively. In overall, this study aims to further explore the deep dehumidification potential of ILs, and inform ideas for the LDDD development.

Investigation of flow regimes, pressure drop, void fraction, film thickness, friction factor and production of two-phase flow in a perforated horizontal wellbore

This study focuses on investigating the impact of flow patterns on production in perforated horizontal wellbores. According to experimental and numerical results, this paper discussion the behaviour of total pressure drop, mixture superficial velocity, void fraction, liquid film thickness, and production that occur with various flow patterns in a perforated horizontal pipe. The flow patterns were predicted experimentally and numerically using a pipe with a length of 3 m and an internal diameter of 0.0381 m, with two perforations of inside diameter 0.004 m with a phasing angle of °180, to simulate the complex flow in horizontal wellbores. Total pressure drop and liquid film thickness were reduced by increasing the radial air flow of the perforations. At the same time, void fraction and mixture superficial velocity were observed to increase. Additionally, the film thickness increased with the holdup fraction but decreased with the void fraction. The local friction factor reflected the behaviour of the mixture's superficial velocity during the region of the perforations. The friction factor with the perforated horizontal pipe was greater than that in the unperforated horizontal pipe. The liquid product increased with an increase in the mixture's superficial velocity, and the percentage amounts of production shown were 10%, 40%, and 75%, depending on the water's superficial velocity. The convergence between experimental and numerical results was good during the flow patterns (slug flow and stratified flow). In contrast, some differences in the static pressure drop behaviour occur during flow patterns (bubble flow, dispersed bubble flow, and stratified wave flow).

Experimental and modeling study of bubble absorption-based deep dehumidification using the ionic liquid: Parametric analysis on heat and mass transfer

Conventional liquid desiccant dehumidification is good at humidity control with energy conservation and stable operation, but is limited by corrosion and crystallization in deep dehumidification. Thus, it is necessary to broaden the humidity adjustment range of liquid desiccant deep dehumidification as well as avoid corrosion. Ionic liquids (ILs) with deep dehumidification potential (e.g., extremely low vapor pressure and non-corrosion) are a promising alternative to traditional salt solutions. Meanwhile, the bubble absorption-based mode can obtain a huge gas–liquid specific interfacial area, which is expected to solve the low wettability and insufficient gas–liquid transfer efficiency in traditional falling-film/packed dehumidifiers using IL. In this work, the bubble absorption-based deep dehumidification using IL (BADD-IL) is investigated. Meanwhile, the heat and mass transfer mathematical model of BADD-IL is established, and a bubble column dehumidifier using the novel IL is experimentally examined under different conditions. The results indicated that the deep dehumidification performance is strongly dependent on operating parameters, and the minimum outlet air humidity ratio is around 1.2 g/kgda. In particular, it is most sensitive to inlet air humidity ratio, followed by liquid height and superficial velocity, and the effect of solution temperature is the least. Notably, the influential mechanism of superficial velocity and solution temperature on volumetric transfer coefficient is different. The increase of superficial velocity promotes both gas–liquid specific interfacial area and heat and mass transfer coefficient. For the IL with lower temperature, its higher heat and mass transfer coefficient makes up for the poor specific interfacial area caused by high viscosity. Additionally, the Lewis factor of bubble column dehumidifier using the novel IL is basically less than 0.6, which is important for the device design and scale-up. This study clarifies the heat and mass transfer mechanism of BADD-IL, and provides guidance for the development of ILs deep dehumidification technology.

Investigating the Relationship between the Time Constant Ratio and Plug-Flow Behaviour in the Pneumatic Conveyance of Biomass Material

This study introduces a novel methodology to evaluate the behaviour of biomass material by examining the ratio of aeration and deaeration time constants. To this end, a series of tests were conducted on four different materials, namely, cottonseed, wood chips, wood pellets, and wheat straw, in order to investigate their aeration and deaeration behaviours. The study derives the aeration and deaeration pressure drop equations, and discusses the corresponding time constant expression. Subsequently, the four materials were conveyed in 12 m long batch-fed and continuous pneumatic conveying pipelines to examine their behaviour in longer pipelines. The results indicate that the aeration and deaeration time constants increased with an increase in air superficial velocity. However, the ratio of the aeration and deaeration time constants was identified as a unique number, where a value close to 1 indicates a higher likelihood of plug flow. On the basis of the results, cottonseed, with the lowest ratio of time constant, was more likely to form a stable plug flow in both batch-fed and continuous pneumatic conveying. Given the unique properties of biomass and the limited research on the pneumatic conveyance of biomass, this methodology represents a novel approach for predicting modes of flow in materials with complex properties.

Bubbles in biomass fluidized bed gasifiers: A phenomenological probabilistic predictive model

Bubble properties in fluidized beds including size, velocity, and path, vary randomly. This article proposes a new PPPM (Phenomenological Probabilistic Predictive Model) l, that allows one to establish a vrb-BAC prediction band, to describe bubble data, obtained in a lab scale biomass-sand fluidized bed, by using CREC Optiprobes. The PPPM, represents a significant improvement from an earlier Probabilistic Predictive Model (PPM) reported by Torres and de Lasa in 2021, with the new PPPM being based on a balance of forces including gravity, drag, buoyancy, and minimum fluidization excess velocity. The resulting PPPM bubble rise velocity (vrb) is obtained as a function of the bubble axial chord (BAC) and is specifically evaluated by studying bubbles in a high-density sand (above 2500 kg/m3) fluidized bed. The PPPM leads to a behavioral band showing a normal bubble frequency distribution that becomes increasingly skewed as the gas superficial velocity increases. The proposed PPPM is shown to be applicable to single bubbles in a sand bed at incipient fluidization and to multiple bubbles in a biomass-sand bubbling bed. The PPPM is validated in the present study, by comparing it against 46,000 bubbles, under different gas superficial velocities and biomass loadings. By using the PPPM, it is shown 91% of all bubbles studied fall within the PPPM prediction band. Given the demonstrated ability of the PPPM, it is anticipated that this model will significantly contribute to the development of large-scale multiphase biomass gasifier models.

Characteristics of flow fields in the gas–liquid mini‐bubble columns with particle image velocimetry measurements

AbstractAs a new type of gas–liquid microreactors, the gas–liquid mini‐bubble column has potential applications. However, few studies on the flow fields in the mini‐bubble column can be found at present. In this work, particle image velocimetry (PIV) was used to visually study the velocity fields, vorticity fields and bubble dynamics in the gas–liquid mini‐bubble columns with column inner diameters of 1–3 mm and mini‐bubble diameters ranged from 0.7 to 1.3 mm. It is found that with the increase of superficial liquid velocity, bubbles rose from almost straight line to Z‐shaped or S‐shaped trajectory, and the bubble trajectory changed from one‐dimension to three‐dimension; when the bubble velocity changed, the bubble size and gas holdup decreased; bubble terminal velocity was controlled by bubble buoyancy and flow resistance, and increased slightly with bubble coalescence. These findings may provide basic reference for the design and scale‐up of such a mini‐bubble column reactor.

Determination of Pressure Drop Correlation for Air Flow through Packed Bed of Sinter Particles in Terms of Euler Number

In order to clearly understand the air flow resistance characteristics in vertical tanks for sinter waste heat recovery in the steel industry, experimental research on the air flow pressure drop (FPD) performance in a sinter bed layer (BL) was conducted. Based on a self-made experimental device, the measurement values of air FPD for different experimental conditions were determined firstly, and then the concept of Euler number (Eu) in heat exchangers was introduced into the study of air FPD in BL; the change rules of Eu under different particle diameters were analyzed. Finally, the air FPD correlation in sinter BL was obtained and described in the form of Eu, and the error analysis of obtained air FPD correlation was performed. The results show that, the air FPD increases as a second power relationship with the increase in air superficial velocity when the particle diameter is constant. The decrease amplitude of Eu gradually dwindles when increasing the Reynolds number (Re), and the decrease in the Eu shows a reciprocal relationship with the Re. As the bed geometry factor increases, the FPD coefficient, A, decreases as an exponential relationship, while the FPD coefficient, B, increases as a first power relationship. The obtained air FPD correlation in the form of Eu in the experiment is well compatible with the measurement values, and the mean deviation of obtained correlation is 4.67%, showing good originality.

An Experimental Study of Pressure Drop Characteristics and Flow Resistance Coefficient in a Fluidized Bed for Coal Particle Fluidization

Liquid–solid fluidized beds have a wide range of applications in metallurgical processing, mineral processing, extraction, and wastewater treatment. Great interest on their flow stability and heterogeneous fluidization behaviors has been aroused in research. In this study, various fluidization experiments were performed by adjusting the operating conditions of particle size, particle density, and liquid superficial velocity. For each case, the steady state of liquid–solid fluidization was obtained, and the bed expansion height and pressure drop characteristics were analyzed. The time evolution of pressure drop at different bed heights can truly reflect the liquid–solid heterogeneous fluidization behaviors that are determined by operating conditions. With the increase in superficial liquid velocity, three typical fluidization stages were observed. Accordingly, the flow resistance coefficient was obtained based on the experimental data of bed expansion height and pressure drop. The flow resistance coefficient experiences a decrease with the increase in the modified particle Reynolds number and densimetric Froude number.

Coalescence dynamics of two droplets in T-junction microchannel with a lantern-shaped expansion chamber

BackgroundTo improve the coalescence efficiency of droplets in microchannel, a lantern-shaped expansion chamber is proposed to facilitate droplets coalescence. MethodsA high-speed digital camera was used to study the coalescence process and the mechanism of droplet coalescence was analyzed based on the liquid film draining model. FindingsThe existence of shrinkage mouth could prolong the contact time of droplets and accordingly promote droplet coalescence. The drainage time of continuous phase liquid film decreases with the increase of superficial flow velocity and droplet size, but increases with increasing dispersed phase viscosity. The film drainage time for contact coalescence, squeeze coalescence and tail coalescence increases successively. There exists a minimum critical capillary number Camin and a maximum critical capillary number Camax, and coalescence can occur only when Camin < Ca < Camax. The correlations for predicting the minimum critical capillary number and the maximum critical capillary number are proposed.

Simulation of upward gas—hydrate slurry multiphase flow in a vertical concentric annulus for natural gas hydrate solid fluidization exploitation

The accurate simulation of upward multiphase flow of hydrate slurry in the annulus is one of the key scientific unsolved issues in natural gas hydrate solid fluidization exploitation. In this work, the upward multiphase flow of hydrate slurry in a vertical concentric annulus is simulated. The hydrate slurry hydrodynamic models suitable for pseudo-single-phase flow, bubbly flow, slug flow, and annular flow are proposed, respectively. Finally, the hydrate decomposition kinetic model is combined with the established annulus hydrate slurry multiphase flow model to simulate the multiphase flow of hydrate slurry in the annulus. The factors affecting flow behaviors are analyzed. During the upward flow in the annulus, the hydrate slurry temperature first decreases and then increases. As the inlet temperature increases, the fluid temperature, hydrate decomposition rate, and gas superficial velocity increase. During the upward flow in the annulus, hydrate may be formed again, which indicates that the error may be magnified due to ignoring hydrate formation. The larger the flow rate, the smaller the length of the slug flow. The larger the hydrate volume fraction, the higher the starting point of hydrate decomposition. These findings are of practical value to give a further understanding of hydrate slurry multiphase flow, which can promote further engineering application of natural gas hydrate solid fluidization exploitation.

Wax Deposition Law under a Gas-Liquid Bubbly Flow Pattern.

Under the high-pressure and low-temperature environment of the deep sea, wax deposition will occur in the wellbore. This study discusses the effect of gas–liquid two-phase bubbly flow on wax deposition. In this study, wax deposition experiments of a gas–liquid two-phase flow in vertical pipelines were carried out using waxy white oil and air as the experimental medium. The results show that under the bubble flow pattern, within a short period of time from the start of wax deposition, it rapidly accumulates to the peak, then rapidly cuts off part of it, and then presents a simple harmonic dynamic trend until the final stability. The average wax-deposit thickness decreases first and then increases with the increase of superficial gas velocity, and it increases first and then decreases with the increase of superficial liquid velocity. The average wax-deposit thickness decreases with the increase of oil temperature. The average wax-deposit thickness was substantially constant and then decreases with the increase of ambient temperature. The wax-deposit thickness increases with the increase of wax content in oil flow. This research is useful for people to further understand the changes in the wax deposition process.

Experimental Investigation of Oil-Water Two-Phase Flow in Horizontal, Inclined, and Vertical Large-Diameter Pipes: Determination of Flow Patterns, Holdup, and Pressure Drop

Summary Liquid-liquid phase flow in pipes merits further investigation as a challenging issue that has very rich physics and is faced in everyday applications. It is the main problem challenging the fluid flow mechanism in the oil and gas industry. The pressure gradient of liquid flow and flow pattern are still the topics of numerous research projects. In this paper, the emphasis is on further investigation to research the flow pattern, water holdup (HW), and pressure decrease for vertical, horizontal, and inclined flow directions of oil and water flows. Test section lines of 4.19-in. (106.426 mm) inner diameter (ID) and 5-m horizontal, 5-m inclined, and 5-m vertical test sections were serially connected. The experiments were conducted at 40°C using 2-cp viscosity oil and tap water, and oil density of 850 kg/m3, at the standard conditions. Fifty experiments were executed at 250 kPa at the multiphase flow test facility, with horizontal, upward (0.6° and 4°), downward (−0.6° and −4°) hilly terrain and vertical pipes. The oil and water superficial velocities were changed between 0.03 and 2 m/s. This evidence was obtained using video recordings; the flow patterns were observed, and the selection of each flow pattern was depicted for each condition. For horizontal and inclined flow, new flow patterns were documented (e.g., oil transfer in a line forms at the top of the pipeline, typically at high water rate, and water transfer at the lower part of the pipe at a high oil rate). The data were taken at each flow condition, resulting in new holdup and pressure drop. The results show that the flow rate and the pipe inclination angle have major impacts on the holdup and pressure drop performances. In the vertical flow, a clear peak was demonstrated by experiments after the superficial oil velocity reached a certain value. This peak is known as phase inversion point, where after this peak, the pressure starts declining as the superficial oil velocity increases. Also, slippage has been observed after varying inlet oil flow rates between the two phases. The experiments showed that with minor alteration in the inclination angle, the slippage was significantly changed. This study presented new experimental results (measured mainly at horizontal, inclined, and vertical flow conditions) of HW, flow pattern, and pressure drop. These findings are key evidence of the evolving oil-water and flowline estimate models.

Effect of Wall Heat Transfer on the Fluidization Process

The fluidized bed and the fluidization process and characteristics were studied in this paper numerically using Computational Fluid Dynamics (CFD) Ansys Fluent 15.0. Constant temperature was applied to both sides of the two-dimensional fluidized bed geometry. The superficial velocity of the working fluid ranged amid (0.08 – 0.5 m/s) and the initial height of the solid particles changed amid (0.05, 0.1, 0.2 m). Aluminum particles and water was used as working materials within the fluidized bed. The model used for the investigations was validated using Ngoh and Lim research results. The results showed that the fluidization head increases as the water inlet superficial velocity increases. As well as when the water inlet superficial velocity increases, the average solid phase temperature increases.

A novel method to investigate detachment of particulate structures from an elastic single fiber at low gas flow velocities

The detachment of particle structures from a stiff single fiber exposed to an airflow has been investigated by (Jankowska et al., 2000; Larsen, 1958; Löffler, 1972; Przekop et al., 2004; Qian et al., 1997; Zoller et al., 2020). In order to detach particle piles from a stiff single fiber, airflow velocities above 1.2 m/s are required. While these values are well above typical operational parameter for depth filters, a shift toward lower velocities for detachment would offer both up-and downside for filter operation. One possible application for controlled structure detachment from a filter fiber at lower velocities would be a shift of separated particulate structures from the upper layers of depth filter into lower regions. The result would be additional void space from particle deposition. Currently there is no knowledge available, if fiber stretching could enable such detachment of particle structure fragments at an operation airflow velocity below 1 m/s. It is assumed that fiber stretching might introduce shear and tensile stress to the particulate structures. That may lead to first cracks and promote final detachment. This study examines the behavior of particle structure fragments on an elastic single fiber for the first time. The fiber is loaded with a compact particle structure in a loading chamber. Glass spheres served as inert particulate material. A new customized fiber-mounting device was designed for the stretching procedure of 22 mm (55%) length. In first experiments, the fiber was stretched without an airflow. Stretching at an elongation rate of 0.4 mm/s caused re-arrangement, crack formation and rotation of the fiber. No detachment of particle structure fragments is observed. If the fiber is stretched and exposed to an airflow at 0.8 m/s, particles structure fragments re-arranged and subsequently detached. In further experiments at an elongation rate of 1.2 mm/s, intensive detachment is observed at an increase of superficial airflow velocity from 0.4 m/s to 0.8 m/s. In total, this reveals that fiber stretching enables detachment of particle structure fragments from a single fiber exposed to an airflow at superficial velocities below 1 m/s. The potential application of elastic fibers in a filter system will have the aim to delay increasing filter backpressure. This effect could be caused by the transport of particulate matter towards areas of lower loading further downstream while maintaining a high level of separation efficiency at operational filtration velocities.

Experimental Analysis of Water/Oil Displacement Tests in Horizontal Pipe

Summary Production shutdowns occur often throughout the life cycle of an oil field. In offshore fields, shutdown situations are accompanied by an intense heat exchange between pipeline and cold water, which exponentially increases oil viscosity. Such an event may lead to serious difficulty to restart the production, or even render it unfeasible, especially for heavy oil fields. Therefore, a preventive procedure is required to remove the ultraviscous oil from pipelines and risers; for example, by pumping diesel or methanol in a flush procedure. Designing an efficient cleanup procedure is therefore essential in terms of time, amount of fluid injected, and pumping system requirements. However, the amount of research published in this area is limited. In this paper, we propose a comprehensive analysis on how the displacement of a viscous liquid by a less-viscous liquid occurs in a pipeline through footages in different segments, varying the injection velocity. Two mineral oils with different viscosities and tap water were used as working fluids for this study. The experimental setup was built with a horizontal 10-m-long acrylic pipe with 19-mm internal diameter. Two high-speed cameras were placed both in the inlet and outlet segments. Our results demonstrate how water displaces viscous oil in a pipeline, showing different flow configurations as superficial water velocity increases, depending on the oil viscosity and distance from the inlet. A dimensionless analysis was performed by a combination of the forces that govern the flow and dimensionless groups found in literature. The results show an expected area of optimum values regarding cleaning time according to flow configuration. A unidimensional model using a logistic function was proposed and showed a good agreement with the experimental data. The model itself proven to be an easy tool for industry and academic purposes, supporting even more robust and elaborated models in the future.