Lab Effect of the Flow Rate of Saltwater vs. Freshwater

Lab Effect of the Flow Rate of Saltwater vs. Freshwater

Aim of the Experiment

In this experiment, I will examine the correlation between the flow rate of saltwater and Freshwater, the pressure drop of the fluids, and temperature variation. Effects of salinity and pressure drop of the fluids will be evaluated using appropriate apparatus under different temperature. The flow rate was to be assessed using a venturi tube, that is connected to a sensor that will record and send the retrieved data to the required section for the analysis of the general performance. To complete this experiment five trials were to be completed and the readings for each trial were noted and compared hence maintaining the validity of the final result. Each trial was to be identical to the first with the expectation of a change in the applied temperature and pressure using appropriate apparatus. Within this experiment it was found that there is a high correspondence between pressure drop of a fluid and flow rate. The key results that were obtained from the analysis were that the passage efficiency, the coefficient of the discharge, and the pressure drop were all similar, with the end results being slightly skewed by 0.5. I predicted that there would be a correlation between drop of a fluids and flow rate which in fact was shown throughout the experiment. However, the analysis aims at analyzing the resulting levels of saltation, flow rate, temperature, and pressure from varying salinity compositions in saltwater and Freshwater.

Introduction

The experiment was finished in a lab-scale, permeable media tank to examine the saltwater wedge in a freshwater spring. Three kinds of trials were performed to grow: consistent state salt-wedge information saw under various water-powered slope conditions, transient salt-wedge information saw under meddling wedge conditions, and transient salt-wedge information saw under retreating wedge conditions. Moreover, motion estimations were made to measure the stream qualities of three particular consistent state tests. The saltwater interruption model SEAWAT was utilized to recreate these informational collections. The model outcomes alongside the exploratory information are introduced as benchmark issues for testing thickness coupled groundwater stream models. A value investigation was finished to test the affectability of these exploratory issues to thickness coupling impacts. The consequences of this research show that the proposed benchmark is an increasingly compelling option in contrast to the customary Henry issue. These new test informational collections can be utilized to evaluate the exhibition of saltwater interruption models under both consistent state and transient conditions.

Background

The administration of saltwater interruption into beachfront springs is one of the most testing ecological administration issues looked by water asset organizers around the world. The disruption of saltwater into groundwater springs is typically forestalled by the surrounding groundwater transition releasing toward the sea. Be that as it may, overexploitation of beachfront springs has brought down groundwater levels and decreased freshwater motion. This has prompted extreme saltwater interruption issues in a few metropolitan territories. Moreover, disastrous occasions, for example, torrents and tropical storms, can infuse salt water into neighborhood springs and debase enormous volumes of new water saves (Barlow et al., 2003). In this way, understanding the blending elements of saltwater inside freshwater spring frameworks is a significant research problem. Displaying saltwater streams in freshwater structures requires numerical codes that can settle thickness coupled stream and transport conditions. The presentation of these codes is regularly approved by tackling a lot of benchmark issues. The most frequently utilized benchmark issue for testing saltwater interruption codes is the Henry issue. This issue depends on a diagnostic arrangement created by Harold Henry in his Ph.D. exposition (Henry, 1960). Henry considered salt-wedge transport issues in a rectangular, soaked, two-dimensional, kept permeable media space. He embraced a scientific arrangement created by Poots (1958), which was initially utilized for displaying heat move forms, for understanding his consistent state saltwater interruption issue.

Overview

Examinations were directed in a rectangular stream tank. The tank was developed utilizing 6-mm thick Plexiglass TM. The inside components of the permeable media district are 53 cm (length) 2.7 cm (width) 30.5 cm(height). The stream tank was separated into three unmistakable chambers: a focal stream chamber containing the permeable medium and two steady head chambers containing saltwater and Freshwater before the test, the tank was pressed with wet permeable medium under completely immersed conditions; this methodology helped us keep away from air entanglement. The pressing was done in layers of around 5 cm. In the wake of conveying the permeable media in each layer, the tank and the permeable medium were packed to accomplish homogeneous pressing conditions. The pressure-driven conductivity of the permeable medium was evaluated by setting up a uniform stream field through the framework and estimating the water-powered slope and the relating volumetric release (Barlow, et al., 2003). The course through the framework under different inclination conditions was estimated, and the normal in situ water-powered conductivity esteem was along these lines determined to utilize Darcy’s law. The general conductivity of research facility scale spring models would rely upon pressing conditions; henceforth an in-situ technique is the most fitting strategy for evaluating the normal water powered conductivity esteem (Oostrom et al., 1992). Utilizing the in situ approach, the normal water powered conductivity estimation of the stream tank was assessed to be 1050 (±25) m/day. A tracer test was led by instantaneously injecting a slug of tracer into the Freshwater and saltwater chamber; this permitted a long beat of tracer to create alongside the whole tallness of the case. The beat was permitted to move over the stream area. The homogeneity of the pressing was guaranteed by outwardly confirming the consistency of the beat as it moved through the framework. Lab perceptions demonstrated next to no spreading, and the tracer front was moderately sharp. A vehicle model reenactment with a longitudinal dispersity estimation of 1 mm, which is of the request for the normal grain distance across, could foresee the normal spreading saw in the tracer test. Such small dispersity estimations (of about a millimeter) have been recently revealed for comparative uniform permeable media frameworks (Dey, 2020).

OBJECTIVES OF THE EXPERIMENT

Overall objective: The overall aim is to confirm the correlation between the of the saltwater and Freshwater as well as the drop of a fluid system and flow rate.

Specific objectives: The specific aim is to assess the efficiency of the saltwater and Freshwater and the coefficient of discharge of the venturi meter.

Hypothesis:

If the flow rate is decreased or increased when the level of salinity increases.

If the pressure of a drop fluid system will increase; therefore, if the flow rate is increased or decreased, the pressure of a drop fluid will decrease.

Purpose of this experiment:

Fluid flow rate is related to real world’s applications due to the movement of fluid

through pipelines. The flow rate in a pipe is the Volume of fluid each second that is passing through a cross-sectional segment of the pipe. Knowing the flow rate through pipelines allows an individual to understand better that the higher velocities of fluid can decrease the life of the pipes due to the possibility of erosion and serge pressures. Given this flow rate information, an expert can optimize the pressure and head throughout a network of pipelines. Therefore, I am interested in this experiment to apply learned equations to a live application. This experiment includes finding venturi flow, paddle wheel flow, and actual flow rate.

Variables

Dependent

In request to examine the vertical progression of variable thickness liquid in various ways and talk about the attainability and effectiveness of the reclamation of saltwater, a one-dimensional vertical model is built up to mimic the underground saltwater body in the upright bearing. The model comprises of a fundamental body and a gadget of water gracefully. The fundamental body of the model is an empty chamber made in natural glass (the external distance across is 7 cm, the inward measurement is 5 cm, and the tallness is 120 cm). So as to guarantee the air snugness of the test, the two parts of the bargains are fixed by the elastic fitting. The upper elastic attachment and the lower one is punctured by a needle, as the delta and outlet.

Independent

Independent (cause – x) and dependent (effect – y) variables

Flow Rate (x) Pressure (y)

Controlled

The apparatus for measuring were kept constant throughout the experiment. This action was controlled to ensure that the result was to be compared uniformly. However, other conditions such as temperature, pressure and outlet pipes for venturi were also kept constant with an aim of making the results valid.

Apparatus

• Materials List: In order to conduct this, experiment the following materials will be needed:

1. 1. 1. Protractor: To measure and set the angle of the trough leading into the container.
      2. Venturi tube
      3. Fine sieve: A sieve to filter out the water from the sand.
      4. Scale: A scale to measure the amount of sand deposited into the container.
      5. Trough: A trough to pour the water down and hold the listed sediment/
      6. .20 lbs of sediment: Sediment to laid within the trough.
      7. Large container: Container to catch the deposited water and sediment.
      8. Funnel: A funnel to control the velocity of the water being poured down the trough.
      9. Duct Tape: To hold the trough, funnel and container together and in place.
      10. 3 cups
          1. Saltwater (20 grams of salt added to 4 ounces of water)
          2. Freshwater
          3. 50/50 mix (10 grams of salt added to 4 ounces of water)

Method

1. First prepare three cups of water with about 4 ounces of water in each; the first with Freshwater (tap water), the second with freshwater mixed thoroughly with 20 grams of salt, and the third with freshwater mixed with 10 grams of salt.
2. Setup the container and connect the trough to the container at a 15-degree angle so that the trough is angled into the container. Once the trough is angled correctly duct tape the two together.

• Next, duct tape the funnel to the end of the trough farthest away from the funnel so that the spout of the funnel is perpendicular to the ground

1. Record the weight of the amount of sediment used to be laid in the trough
2. Next, evenly layer the trough with sediment

Observation

            Our experiment was designed so that saltwater would pass through a physically and chemically mechanized filter and then fall as “clean water” into a glass beaker. The materials we used were two plastic water bottles, two coffee filters, and grinded charcoal. To build our filter we cut a water bottle in half, placed the upper half of the water bottle inside the bottom half (facing down), stuffed the upper half of the water bottle with two coffee filters, poured about ⅛ of a cup of grinded charcoal into the coffee filters, placed another upper half of a water bottle on top of the coffee filters, and taped the core of the filter together. To test for the presence of salt in the collected water we used a conductivity probe because of the huge gap between the conductivity of salt and water. Our experimental procedure was quick and simple. First, we measured the conductivity of 250mL of saltwater using the conductivity probe. Then, one of our group members held our filter slightly above an empty 300 mL beaker. Next, we poured the 250 mL of saltwater into the filter. Lastly, we measured the conductivity of the saltwater that made it to the previously empty beaker.

Data Collection and Analysis

Graphical presentation of Rate against temperature for Salt water

From the above graph, the graph can be extrapolated to arrive to the notion that, saltwater has a lower freezing point because of its salinity. The higher the salinity is, the lower the freezing point is. Therefore, salt is the element of lowering the freezing point. As a result, people often spread salt on icy roads during inclement conditions so that the ice on the road gets melt faster.

Graphical presentation of Rate against temperature for both Saltwater and Freshwater

Data Analysis

While completing the experiment there were statistical uncertainties that arose for several different reasons. One uncertainty that arose within the experiment was human error in several different forms. One uncertainty that arose was manually calculating the initial rate of flow within the pipelines (Dey, 2020). I was required to use a stopwatch as well as using the hand to calculate the amount of water that was disposed out of the pipelines, every five seconds. During the experiment due to human time reactivity the flow of water was not always stopped exactly at five seconds. After timing the flow of water for approximately five seconds I had to calculate the Volume of water, hence the experiment required maximum keenness to obtain valid results. This allowed for an approximation due to placing the water inside a graduated cylinder, which does not give an exact volume of fluids. This caused an issue within the experiment due to the calculations since the amount of water being used was not exact.

Validity of Experiment: Yes, the experiment is valid as flow rate differ amid saltwater water and fresh water as well as the decrease in pressure under diverse range of temperatures (Park, et al., 2008). The data gathering recorded a higher possibility of result deviation throughout the experiment hence its validity.

Table1: Rate for temperature range of 85℃

Table1: Rate for temperature range of 65℃

Table1: Rate for temperature range of 35℃

Table1: Rate for temperature range of 20℃

Table1: Rate for temperature range of 8℃

From the data collected above, it was observed that during the flow through the attached venturi (between the Freshwater and saltwater), temperature range was a great determinant of the flow rate. I measured the change in salinity and recorded about 11.38ppt. as final measurement. The resulting salinity drop within the saltwater was 6.64 ppt. In conclusion, the flow of Freshwater resulted in a drop in salinity levels within the experiment because of the dilution of saltwater by Freshwater (Barlow, et al., 2003).

Results

Venturi meter measures the flow rate by taking account pressure differential across it. During the experiment the venturi flow rate measured has little to no difference from the actual flow rate. The findings were skewed by 0.01 in three out of five trials. The freshwater flow rates in all five trials also have a high correspondence with saltwater flow rates. In all five trails the measurements were skewed by 0.01 increments. Also, within the experiment I also noticed that as the valve closed the pressure differential across the flow increases (Park, et al., 2008). In these 6 experiments, the efficiency of flow rate might have not been precise due to human error which includes not having exact increments of five seconds in between each trial. The data obtained was tabulated as shown below.

Table4: The Venturi readings for time and Volume

Discussion

In this experiment, the results from the experiment revealed that by increasing salinity levels, more sediment was eroded.  Furthermore, by increasing levels of salinity the slower amount of time it took for sediment to be eroded or carried downstream (Park, et al., 2008).  Salinity levels affect the amount of time and sediment eroded. The following graph presents the collected data and definitively supports our hypothesis that the higher the salinity of water, the more buoyancy that will be created, causing sediment to be carried further. The saltwater in the experiment took more time to flow through the trough because it has a higher inherent viscosity and is more buoyant, which allowed it to carry more sediment. The results from this model can be accurately applied to a real-world context as coastal waterways are deeper and have slower moving water while freshwater systems are shallow and have faster moving water. Moreover, higher saltation deposition will cause highly salinized waterways to be deeper and wider while freshwater rivers and streams will be shallower and narrower with faster moving water. The discussion can be well illustrated by the data below.

Table 5: Effect of temperature on both saltwater and Freshwater

Quantitative conclusions

From the 250mL of saltwater we poured into the filter, I collected 230mL with a flow

rate of 3.48 mL/s. As flow rate increases pressure drop, discharge coefficient, and passage efficiencies decreased in saltwater as it was more in Freshwater (Park, et al., 2008). However, when the flow rate decreased pressure dropped, discharge coefficient, and passage efficiencies increased as well. Therefore, the assumption can be made that if pressure drop increases discharge coefficient and passage efficiency will also increase and vice versa.

Qualitative conclusions

The range of the flow rate measured from 2.083gpm to 2.32 gpm. The range of pressure drop measured from 0.6 psi to 2.55 psi. The reasoning for the maximum and minimum pressure is because venturi pressure is significantly lower than the pump pressure (Dey, 2020). The maximum flow rate in the system was 2.32 gpm. There was little to no difference in the flow rates as seen in the data the difference was only 0.01 gpm from each flow rate to the next. The coefficient of discharge above 1.0 means that there was more energy than when the experiment was started. The results being over 1.0 in two of the trails could be the result of human error. The result efficiency gradually increased with the flow rate until around the maximum of the flow rate when it dropped significantly (Sullivan, 2016). From the result obtained, it was evident that temperature increased with an increase in the rate, therefore the readings for the temperature range 8 to 85 was analyzed for each type of the fluid and the overall observation was that the temperature has effect to both saltwater and Freshwater.

Table:6 Temperature and Rate for saltwater

Limitation of the Experiment

A limitation that was placed upon this experiment was human error. Within the trials I was required to time the rate of flow with a stop watch. This causes a limitation for the experiment due to human reactivity. Human reactivity played a role as to why each trial was not exact five seconds long therefore causing data to be slightly unreliable. Another limitation that occurred was the need for a larger control container to dispense the fluid into. Largely, this was a limitation due to not having adequate amounts of space for all of the fluids to be placed into therefore having to transfer liquids which would skew the results as well (Sullivan, 2016). One last limitation that occurred during the experiment was the usage of a gradated cylinder. Graduated cylinders are used for approximations therefore the results in the amount of fluids dispensed was not an accurate reading. However, these limitations were not detrimental to the results that were found from the experiment.

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Barlow, P. M. (2003). Ground water in freshwater-saltwater environments of the Atlantic

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