Dissolved Oxygen variation in

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Dissolved Oxygen variation in AIT Pond Channel
System
By

• Bala

AIT

• Amit

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AIT pond
-Recreational Uses -Well developed aquatic
ecosystem -Diurnal oxygen variation
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Aquatic Ecosystem
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Why Oxygen???

• Important life sustaining parameter
• High diurnal variation
• Driving force for all reactions

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Oxygen System

• State variables
• DO
• BOD
• Primary producers
• Processes
• Photosynthesis
• Respiration
• Re-aeration
• Forcing functions
• Sunlight
• Temperatures

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What..?
Outlet
AIT Bldg.
Pond
Main Adm. Bldg.
RCC Bldg.
Academic Bldg.
CLET Bldg.
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Modeling Framework

• Forming basic equations
• Simulations using existing data
• Generating fresh data
• Validations of results
• Consistency checking

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How..?
Basics Mass Balance
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Assumptions

• Complete mixing in each horizontal segment
• Negligible vertical variation of DO BOD
• Constant Respiration in each horizontal segment
• Negligible Nitrogen demand

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General Mass Balance Equations

• Water Balance

• BOD Balance

• DO Balance

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Ev
Ev
Ev
Calibration
c
r p
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Verification

• With raw data to obtain
• Photosynthesis
• Respiration values
• Checking Mass balance of the system

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Model validity

• The validity is questionable for
• Assuming constant volume in segment at all times
• Assuming constant Sunlight intensity throughout
• the day
• Assuming constant reaeration constant

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Simulation
Let computer do the calculations and Engineer
the thinking