Senior Design Project 13373 Mission Statement

Project # Project Name Project Track Project Family13373 Nanofluidic

CharacterizationSystems and Controls None

Start Term Team Guide Project Sponsor Doc. Revision2012-1 Mike Zona Professor Schrlau 1

Project Description

Project Background:The use of nanoporous membranes is ideal for medicinal uses, in which extremely low flow is a necessity. One such case is to use these example membranes to control the injection of cells and other microscopic test specimens. Currently however, there are no definitive ways to measure flow characteristics across nanoporous membranes accurately.

Problem Statement:The objective of this project is to characterize the flow rates through nanoporous membranes using different parameters for the flow. This will be achieved by using different gauges that output data onto a computer program showing the values for the flow rate, pressure and temperature rates of the fluid. This way, the characteristics of different variations of membranes can be analyzed for future use. Since flow going through the membrane is small, flow is expected to be non-Newtonian and not conform to common calculations.

Objectives/Scope:1. Quantify expected flow across membrane

through calculations and assumptions2. Reduce the cost of measurement devices

and system parts 3. Ability to physically observe the flow

outside the system as well as under a microscope

4. Collect and store all data from within the system itself

5. Ability to change the flow rate of the system as well as control the sampling rate of data collection

Deliverables: Bill of materials CAD drawings Electrical Layout

Updated Risk Assessment MSD2 Gantt Chart

Expected Project Benefits: Provide data that successfully

characterizes flow across membranes. Ability to change flow rate through the

system Keeping computerized records of all

calculated and measured values obtained from the system

Core Team Members: Justin Davis Dave West Dave Sharp

Strategy & Approach

Assumptions & Constraints:1. System must be able to withstand

high pressure flow rates2. Output data can be analyzed and

edited for further calculations3. Cost must be within a certain budget

limit while still meeting customer criteria and specifications

Risks and Other Info: Project Risks

No strong LabVIEW Background Parts ordered may be incorrect or

not able to function properly Lack of communication within group

could lead to potentially missing functionality.

Device Interface Risks Measurement devices may not sync

correctly to the system Size of overall system may be

unable to be observed under a microscope

Slight delays in data collection

Senior Design Project 13373 Mission Statement

Available Resources Order Parts/Hardware

Lead Time Previous testing system information

Today’s AgendaMeeting Purpose: To determine the most feasible system available in order to perform flow testing across

membranes.

Materials to be reviewed:

Customer Needs

Engineering Specifications

System Calculations

System Considerations

o CAD Drawings

o Parts Analysis

Computer Interface

Test Procedure

Risk Assessment

Scheduling

Final Thoughts and Considerations

Meeting Date: November 9, 2012

Meeting Location: 9-2030

Meeting time: 3:00 pm – 5:00pm

Customer Needs Pareto

 

A B C D E F G H I J K L M N O P Q R

Tota

l

Porta

ble

Use

r frie

ndly

Easy

to

Mai

ntai

n, A

ssem

ble,

an

d D

isas

sem

ble

H

ard

pipi

ng

Fram

e

Diff

eren

t siz

e m

embr

anes

Ble

ed s

yste

m a

nd e

xcha

nge

fluid

Mea

sure

pre

ssur

e

Mea

sure

tem

p

Mea

sure

flow

rate

Rea

l Tim

e V

isua

lizat

ion

Stor

ing

and

Editi

ng D

ata

Use

r Sel

ecta

ble

Flo

w R

ate

Inje

ct S

econ

dary

Flu

id

Fit i

n M

icro

scop

e

Sof

twar

e

Aqu

ire a

nd C

ompa

re S

elec

ted

Mea

sure

men

tsA

djus

t Sam

plin

g R

ate

A Portable                                     6B User friendly B                                   8

CEasy Maintain, Assemble, and Disassemble

C C                                 9

D Hard piping D B C                               7E Frame A B C D                             2

F Different size membranes A B C D F                           4

GBleed system and exchange fluid

G G G G G G                         11

H Measure pressure H H H H H H H                       16

I Measure temp I I I I I I I H                     15

J Measure flow rate J J J J J J J J J                   17

K Real Time Visualization A B C D K F G H I J                 3

L Storing and Editing Data L L L L L L L H I J L               12

M User Selectable Flow Rate M M M M M M M H I J M M             14

N Inject Secondary Fluid N N N N N N G H I J N L M           10

O Fit in Microscope A B C D E F G H I J K L M N         0

P Software P P P P P P P H I J P P M P P       13

Q

Aquire and Compare Selected Measurements

A B C D E F G H I J K L M N Q P     1

R Adjust Sampling Rate A B C D R R G H I J R L M N R P R   5

Total 6 8 9 7 2 4 11 16 15 17 3 12 14 10 0 13 1 5  Importance Rating 2 3 3 3 1 2 4 5 5 5 2 4 4 3 1 4 1 2  

After dicussing the needs with the customer, the ratings for some of the needs have been slightly altered to obtain a better direction for the purpose and use of the system. Since the flow and temperature only needs to be validated, only one of each sensor is required, however the differential pressure sensors is a nessesity.

Engineering Specifications

Spec # Specification (metric) Unit of

Measure Marginal Value Expected ValuesS 1 Test rig size limit (l x w x h) mm 200x120x100 375X120X108S 2 Membrane diameter mm 13 - 25 13S 3 Development cost $ < 2,500 < 2,500S 4 Measuring pressure range kPa < 500 <690S 5 Measuring pressure accuracy Pa 0.1 1725S 6 Measuring flow rate range mL/min 0 - 3 0-5S 7 Measuring flow rate accuracy micoliter/s 0.001 2.5S 8 Measuring temperature range ᵒC from -20 to 100 from -20 to 100S 9 Measuring temperature accuracy ᵒC 0.01 1

S 10 Fine sampling rate per second 100 100S 11 Coarse sampling rate per minute 1 1

After discussing the MATLAB calculations with the customer, the original specs were changed in order to better reflect the expected values observed. Since the pressure differences found seem to increase greatly with very small changes in flow and pore size diameter, the pressure accuracy was deemed to not need to be as small as originally expected. Also, since the temperature value does not change the characteristics of flow, the accuracy of the temperature sensor does not need to be small as well.

Since the main concern for testing will be the 13mm diameter membrane, the system will mostly reflect testing values for that size membrane. Also, the size of the rig itself can be slightly larger, so long as it is still portable and easy to use and assemble.

Engineering Specification Verification

1. Rig Size Equipment Needed: Aluminum FrameTest Details: The rig size will include each of the sensors, the membrane holder, and any connections used in the system. The size limitation will not include the size of the pump, or the drainage system. When the rig is fully assembled, it will be supported using a manufactured frame to keep the system held in place. The rig will be easy to transport as well as assemble and disassemble. This frame will be manufactured from aluminum and will have clamps that hold the tubing and sensors in place.

2. Data StorageEquipment Needed: LabVIEWTest Details: All data collected from the sensors will be outputted to LabVIEW, where the data can be visually seen via a graphical user interface (GUI) and saved onto other programs (excel, MATLAB) for further analysis. The sample rate at which the data is collected will also be implemented into LabVIEW. The data inputs should be obtained using a USB input.

3. Membrane Diameter Equipment Needed: Membrane HolderTest Details: The membrane will be held inside a clear plastic frame where the flow can be visually seen. The membrane holder itself will be capable of housing a 13mm diameter membrane, and will be placed between two pressure sensors within the system.

4. Development Cost Test Details: The development cost will keep the constructed system affordable while still able to take flow measurements across the system. This cost includes all sensors, connections, and the pump used to perform the experiment, but will not include the membranes themselves.

5. Pressure measurementsEquipment Needed: Pressure TransducerTest Details: The pressure drop across the membrane itself will be measured by taking readings at both sides of the membrane holder and taking the difference between the two sides. This information will then be input onto LabVIEW using a DAQ device. Based on the calculations done through MATLAB, the pressure change is much higher for minimum flow change, meaning the pressure transducer resolution does not need to be small, but should still be able to measure a resolution of approximately .5 PSI.

6. Flow MeasurementsEquipment Needed: Flow sensor Test Details: The flow rate going through the system will be validated using a flow sensor able to measure low flow rates of 0-5ml/min with an accuracy of 2.5 µL/s. This data will then be input into a computer using its own USB input device, which will be read by LabVIEW for further analysis. The sensor will be placed just before the first pressure sensor to ensure that the correct amount of flow is going through the system.

7. Temperature AccuracyEquipment Needed: ThermocoupleTest Details: To make sure the fluid is at a consistent temperature, a thermocouple is placed in the system. The data collected from the thermocouple will be input into a computer using a USB converter to be input into LabVIEW. Since the effects of temperature are negligible for this system, the thermocouple does not need to be highly accurate.

8. Adjustable Flow Rate Equipment Needed: Syringe PumpTest Details: A syringe pump will be used in order to properly inject and control the amount of fluid flowing into the system. The pump will be able to induce flow rates up to 60ml/min with a pressure of 60psi.

9. Secondary Fluid Injection Equipment Needed: T FittingTest Details: A secondary injection Luer T-fitting will be placed just before the membrane holder. In the case that a secondary fluid needs to be injected, a syringe will be connected to the fitting so that the fluid can be manually injected into the system when desired. If no secondary fluid is to be injected, the fitting is simply sealed and testing will resume.

10. Fluid DischargeEquipment Needed: BeakerTest Details: The fluid at the end of the system will be discharged into a beaker. It was determined that no complicated exit was necessary for the fluid to be dumped into.

System Calculations Given:

1. Test rig size limit (l x w x h) = 200x120x100 mm2. Membrane diameter =13 - 25 mm 3. Pressure range < 500 kPa4. Rate range = 0 - 10 mL/min5. Temperature range = -20 to 100 deg C

Find: Pressure Drop across membrane for varying flow rates

Assumptions: 1. Laminar Flow through the pipe2. Standard Temperature and Pressure3. Fully Developed Flow4. Steady Flow5. Incompressible Flow6. Constant Pore Density7. 13mm Diameter Membrane8. Max Pressure at 80psi (500 kPa)

Analysis:

Flow Velocity:

Reynolds Number:

Differential Pressure:

Computer Calculations Variables Used:

P1 = 500000 PaD1 = (1/8)*.0254 m Entrance PipeD2 = 4*10^-3 m Holder InletD3 = 9*10^-3 m Holder Fill ChamberD4 = 147*10^-9 m MembraneD5 = 15*10^-3 m Holder OutletD6 = (1/8)*.0254 m Entrance PipeL1 = 1*.0254 m Entrance PipeL2 = 10*10^-3 m Holder InletL3 = 4*10^-3 m Holder Fill ChamberL4 = 58*10^-6 m Membrane ThicknessL5 = 15*10^-3 m Holder OutletL6 = 1*.0254 m Exit PipeMu = 1.002*10^-3 Ns/m^2 viscosityN = 7.36*10^8 Pores per membranek = .5; loss coefficientp = 998.2; % kgm/s^2 density

Finding P (Including Head Loss)

P_Final =... -((Q*128*mu*L6)/(pi*D6^4))-(.5*k*p*(Q/(pi*D5^2)))... - ((Q*128*mu*L5)/ (pi*D5^4))... -((Q_NTube*128*mu*L4)/(pi*D4^4))-(.5*k*p*(Q/(pi*D3^2)))... -((Q*128*mu*L3)/(pi*D3^4))-(.5*k*p*(Q/(pi*D2^2)))... -((Q*128*mu*L2)/(pi*D2^4))-(.5*k*p*(Q/(pi*D1^2)))... - ((Q*128*mu*L1)/ (pi*D1^4))... +P1;

Pressure Drop vs. Temperature Change

P_Temp =... -((Q_Constant*128*mu*L6)/(pi*D6^4))-(.5*k*p_New*(Q_Constant/(pi*D5^2)))... - ((Q_Constant*128*mu*L5)/ (pi*D5^4))... -((Q_NTube_Constant*128*mu*L4)/(pi*D4^4))-(.5*k*p_New*(Q_Constant/(pi*D3^2)))... -((Q_Constant*128*mu*L3)/(pi*D3^4))-(.5*k*p_New*(Q_Constant/(pi*D2^2)))... -((Q_Constant*128*mu*L2)/(pi*D2^4))-(.5*k*p_New*(Q_Constant/(pi*D1^2)))... - ((Q_Constant*128*mu*L1)/ (pi*D1^4));

This graph was an initial test to try to characterize the flow. It modeled the current set up using the 147nm pore diameter and constant temperature.

This graph was made to model what temperature change will do to the pressure drop between the transducers with a constant flow rate of 5 mL/min. Over a range of temperatures (20 to 23 oC) there is almost no change. The pressure change is so small that the y axis cannot resolve it. From this we can determine that minor temperature changes and high temperature accuracy is not an important thing to consider in the final design.

This graph was used to investigate temperature changes at different flows in order to reinforce the assessment from the last graph. Here it is shown that there is a drastically larger effect on pressure drop due to minuscule changes in flow than the entire pressure range used. This serves to prove the observation made before.

This graph was used to test whether the inlet and outlet pipe size mattered greatly on the apparent pressure drop between the two transducers. All of the curves overlap and any differences are undeterminable, showing that the pipe size does not matter at all. Any head loss in the system is minimal. This provides insight that assists us in choosing piping and fittings. Some size can be more expensive than others, so it is valuable to know that using cheaper size tubing will not hurt the results of the experiment.

This graph was used to verify the assessment from the last chart. At different flow speeds, the pressure drop seemed to have a slop of zero as pipe diameter changed. This helps prove the assessment from the last chart as well as provide insight into whether or not the assessment holds true at a higher or lower flow rate (which it does).

This is a graph showing the effect of changing the pore diameter in the membrane has on the pressure drop. The 147nm is the current Nano-pore diameter used, with ranges from no carbon to enough to reduce the tube to 100nm. We used this graph to predict the maximum pressure the pumping mechanism should supply.

System 1: Syringe Pump

Main Components:

Part Name Material QtySyringes Plastic 1

Syringe Pump Hard Plastic 1Flow Sensor Hard Plastic 1

Pressure Transducer Stainless Steel 2Thermocouple Stainless Steel 1

In this system, flow is introduced into the system using a syringe pump. An initial pressure reading, and flow rate readings are taken before the flow goes through the membrane. Then, a final pressure and temperature reading is taken before the fluid exits the system into a beaker. This system is able to measure all three quantities desired within the correct accuracy and budget, however the pressure that it can attain is decreased to 60psi. Although the original pressure range may not be met, this system is still ideal for being able to quantify flow across the membranes within the accuracy derived from the first order calculations.

2: Pressurized Water Tank (Flow Regulator)

Main Components:

Part Name Material QtyWater Tank Painted Steel 1

Flow Regulator - 1Thermocouple Stainless Steel 1

Pressure Transducer Stainless Steel 3TOTAL COST: $2,751.43

For this system, flow is controlled by increasing the pressure within a tank filled with water, and then using a flow regulator to control the amount of flow going through the system. This ensured that a high amount of pressure can be achieved without going over the desired flow rate. Measurements are still taken at the same locations, and will also lead out into a beaker.

Water Tank Analysis:

P1 = 497 kPa

Although this system achieves the desired pressure and flow, the programmability of the pump is lost, leaving the control of the pressure input to be manual. Also, in order to control such low flow, a higher costing flow regulator must be used, causing the system to go over budget.

System 3: Pressurized Water Tank (Flow Valve)

Main Components:

Part Name Material QtyWater Tank Painted Steel 1

Ultra Precision Needle Valve Stainless Steel 1Flow Sensor Hard Plastic 1

Tire pressure gage - 1Pressure Transducer Stainless Steel 2

TOTAL COST: $2,104.40

This system also uses a pressurized tank to obtain the required pressure, but controls the water using a needle valve. The flow rate is then controlled using the flow sensor until the flow desired is achieved. Measurements are still taken at the same locations, and will also lead out into a beaker. These changes to the system also allow for a higher pressure rating at a lower cost, however due to the flow being manually controlled using a valve, the accuracy of the flow rate is lost.

Syringe Pump Schematic Drawings

This system was chosen as the ideal method in measuring and validating fluid flow through a membrane, since it falls within a decent range of measurement accuracy and achieved pressure without going over budget limit.

Measurement System Schematic Exploded View

Detailed Drawings

Membrane Holder Schematic Drawing:

There was a collar around the inlet that was removed to facilitate a threading operation in order to make a hard connection possible.

Thread Coupling Schematic Drawings:

There are two couplings we need to create in order to make all of the other components connect properly. The first is a reduction coupling that has one end fit into a compression fitting and the other facilitates a ¼-28 thread. The other is simply a female to female ¼-28 coupling. The Luer locking mechanisms lent

themselves to the secondary fluid and membrane holder sections well, but attaching them to other types of pipe fittings can be difficult or expensive, so it made more sense just to make these on the lathe in the shop

System Frame Schematic Drawings:

The base was designed to be minimalist and still strong. We did not want the base to be way too heavy, thus losing portability but not too weak where it can’t hold all the components well. The three posts support the apparatus above the table just enough to have clearance, but are as short as we could make them to help avoid tipping. The center post has a bit of a larger hole where it clamps to the pipe because it happens to line up were one of the custom couplings ends up on the line.

System Total Budget

Part Name Material Qty Unit Cost Total Cost Vendor Lead

Time

Flow Syringes Plastic 1 $1.25 $1.25 New Era In stockSyringe Pump Hard Plastic 1 $375.00 $375.00 New Era 2 week

SensorsFlow Sensor* Hard Plastic 1 $1,290.00 $1,290.00 Senserion In stock

Pressure Transducer Stainless Steel 2 $115.00 $230.00 Dwyer2

weeksThermocouple Stainless Steel 1 $38.00 $38.00 Omega In stock

Electrical

Transducer power supply - 1 $49.00 $49.00 Omega In stock

Thermocouple reader - 1 $99.00 $99.00

National Ins. 2days

DAQ Device - 1 $169.00 $169.00National

Ins. 2 days

Fittings

Membrane Holder Plastic 1 $65.83 $65.83 GE 1 weekCompression T-tube

to 1/4" NPT Stainless Steel 1 $38.72 $38.72 McMaster In stockCompression Straight

Fitting Stainless Steel 1 $12.33 $12.33 McMaster In stockSS Tubing 6'

1/4" .035" wall Stainless Steel 1 $18.43 $18.43 McMaster In stock

1/4" NPT cross Stainless Steel 1 $11.52 $11.52 McMaster In stock1/4" npt to 1/4" tubing adapter Stainless Steel 2 $7.92 $15.84 McMaster In StockLuer to 1/4"-28 thread Female Polycarbonate 2 $8.29 $16.58 McMaster In stock

1/4"-28 to 1/4" tube (for flow meter) Stainless Steel 2 $20.14 $40.28 Beswick 1 week

Silicone Tubing 6" 1/4" .035" wall Silicone 1 $3.50 $3.50 McMaster In stock

FrameThread Screws Pack

(100)Black Oxide

Steel 0 $10.86 $0.00 McMaster In stock

Aluminum Frame Aluminum 1 $22.44 $22.44Metals Depot 1 week

TOTAL COST: $2,496.72

*Comes with flow meter, 1/8" tube fitting, pc software, Data cable RS485 with adapter, and A/C Adapter

System Electrical Schematic

LabVIEW Layout

This initial VI file is the first attempt at writing a code to meet the software specifications. Without the instrumentation connected to the computer, one cannot use the data acquisition virtual instruments as they fail a DAQ detection test when entered into the diagram. To begin to write the rest of the diagram without the sensor input, fake data was used from four function generators. This VI displays the flow across the system, the temperature, and the pressure difference at a set time interval. It will also store the data to a text file.

Initial Test Procedure

1. Place membrane within membrane holder and connect to system rig 2. Set syringe pump with set amount of fluid and flow rate

a. If secondary injection is required, repeat process with secondary method 2. Set LabVIEW to measure sensor values at a set rate 3. Run syringe pump for initial time frame to prime system

a. If secondary injection is required, run secondary pump or injection method4. After set time, run LabVIEW program to begin testing values

a. Validate flow rate using omega flow sensorb. Measure Temperature using thermocouplec. Measure pressure before and after membrane using Dwyer sensors

5. Collect all fluid exiting from system using beaker6. After desired testing time elapsed, stop LabVIEW data collection.7. Shut off pump and allow system to bleed remaining fluid, then remove pump8. Output all LabVIEW data as desired 9. If additional tests are required, remove membrane holder from system once of fluid has bleed out the

system and replace membrane

All values obtained are expected to behave similarly to the calculations done in MATLAB; however it is possible to see some spikes in pressure as the fluid flows through the system as seen with the previous system. The system itself holds approximately 10mL.

Risk Assessment

Risk Item Cause Effect R ActionTolerances not met Equipment inaccuracy Data may be inaccurate 9 Accurate

equipment,

More testLong time to assemble

Parts not fitting Work more on assembly 9 Task at hand finished

Flow stops at membrane

Pressure not achieved Rig cannot be tested 9 Re-evaluate flow

Parts don’t fit well Sizing error Leaks in system 6 Find better couplings

Case not functional Calculation error Membrane cannot be tested 6 Re-design frame

Group Miscommunication

Poor Communication Wrong information used 6 Keep Teammates informed

Unprepared Teammates

Poor Management Tasks may be incomplete 4 Keep teammates informed

Lack of Cooperation

Miscommunication Team works poorly 4 Discuss present issues to solve

Customer needs not met

Needs impede function Lack of customer approval 4 Discuss with customer

Sensor Malfunction

Hardware error Readings cannot be obtained 3 Order sensors, repair

Pump Failure Hardware error Test cannot be performed 3 Order new pump/Repair

Components don’t interface

Software error Data cannot be recorded 3 Check connection

Membranes breaking

High flow pressure, stress in casing Membrane cannot be tested 3 Re-design frame

Parts are Late Shipping error Rig cannot be constructed 3 Find alternative parts to obtain

Unstable Frame Constructed poorly Risk of damage 2 Fix frame

Scheduling

Lessons Learned

1. Customer Specifications can change: As research progresses, it is important to stay in contact with the customer as certain wants and needs can become impossible to meet.

2. Communication between group members should be as clear as possible. Lack of proper communication can cause tension and problems as meetings are missed or emails never read.

3. The budget is the driving force. No matter what the customer wants or what the group wants to try, the budget will always have the final word.

4. Data and calculations are a great way to make a point.

5. It is important to know what question to ask in order to get a valuable response.

6. Prove everything.