Wednesday, January 18, 2023

Surge Tanks

Disturbances in water distribution systems can be caused by various situations, including changes in pump operations, valve movements, boundary pressures, demand conditions, and transmission conditions. These disturbances can result in variations in flow, pressure, and water quality, which can impact the overall performance and reliability of the system. The following table summarizes the different types of disturbances and their potential effects on the system:

Disturbance TypeDescriptionPotential Effects
Pump Startup/ShutdownChanges in the operation of pumps in the systemVariations in flow and pressure
Valve Opening/ClosingChanges in the flow area caused by the movement of valvesVariations in flow and pressure
Boundary Pressure ChangesChanges in the level or pressure of reservoirs, tanks, etc.Variations in pressure and water quality
Rapid Demand ChangesSudden changes in water usage, such as hydrant flushingVariations in flow and pressure
Transmission ConditionsChanges in the condition of pipes, such as breaks or leaksVariations in flow and pressure, water quality

It's important to note that water distribution systems are complex systems and disturbances in one area can have knock-on effects in other parts of the system, so it is important to monitor and control the system to ensure stability and reliability.


 Open surge tanks

Closed surge vessels Bladder tanks Hybrid tanks (vented to admit air) Bypass lines Check valves Feed tanks (provide inflow to prevent cavitation) Air release/vacuum valves (2 and 3 stage valves) Pressure relief valves Surge anticipation valves
Type of TankDescriptionAdvantagesDisadvantages
Open Surge TanksThese tanks are open to the atmosphere and allow the excess pressure to be released.- They are relatively simple and inexpensive to construct. <br> - They can be used to prevent the water hammer effect.- They are subject to evaporation and contamination. <br> - They are not suitable for use with hazardous materials.
Closed Surge VesselsThese tanks are sealed and use a compressible gas (such as air) to absorb the excess pressure.- They can be used with hazardous materials. <br> - They are less susceptible to evaporation and contamination.- They are more expensive to construct than open surge tanks. <br> - They require regular maintenance to ensure the compressible gas is at the correct pressure.
Bladder TanksThese tanks use a flexible bladder to separate the water from the compressible gas.- They are less expensive to construct than closed surge vessels. <br> - They require less maintenance than closed surge vessels.- They are not suitable for use with hazardous materials. <br> - They have a limited life-span and need to be replaced periodically.
Hybrid Tanks (vented to admit air)These tanks are similar to closed surge vessels but have a vent to admit air.- They are less expensive to construct than closed surge vessels. <br> - They require less maintenance than closed surge vessels. <br> - They can be used to prevent the water hammer effect.- They are not suitable for use with hazardous materials. <br> - They are subject to evaporation and contamination.
Bypass LinesThese lines allow water to bypass the tank and the pump, reducing the pressure surge.- They reduce the pressure surge. <br> - They are relatively simple and inexpensive to construct.- They can increase the system head loss. <br> - They can increase the pump energy consumption.
Check ValvesThese valves prevent the water from flowing back through the system, reducing the pressure surge.- They reduce the pressure surge. <br> - They are relatively simple and inexpensive to construct.- They can increase the system head loss. <br> - They can increase the pump energy consumption.
Feed TanksThese tanks provide inflow to prevent cavitation.- They prevent cavitation. <br> - They are relatively simple and inexpensive to construct.- They can increase the system head loss. <br> - They can increase the pump energy consumption.
Air Release/Vacuum ValvesThese valves release or admit air to the system to prevent or correct negative pressures. They can have 2 or 3 stages.- They prevent or correct negative pressures. <br> - They are relatively simple and inexpensive to construct.- They can increase the system head loss. <br> - They can increase the pump energy consumption.
Pressure Relief ValvesThese valves release the excess pressure to prevent damage to the system.- They prevent damage to the system. <br> - They are relatively simple and inexpensive to construct.- They can increase the system head loss. <br> - They can increase the pump energy consumption.
Surge Anticipation ValvesThese valves are designed to anticipate and absorb pressure surges in a pipeline.- They anticipate and absorb pressure surges. <br> - They are relatively simple and inexpensive to construct.- They can increase the system head loss. <br> - They can increase the pump energy consumption.

ICM SWMM SQL Code for Links

ICM SWMM SQL Code for Links

This creates a table called "links" with the specified columns to store the link variables. The data types of each column are defined as well. Keep in mind that this is just an example, you may have to tweak it to fit your specific use case. Also, you may want to add more columns and constraints depending on your specific needs.

CREATE TABLE links (
  id INT PRIMARY KEY,
  horiz_ellipse_size_code INT,
  vert_ellipse_size_code INT,
  arch_material VARCHAR(255),
  arch_concrete_size_code INT,
  arch_steel_half_size_code INT,
  arch_steel_inch_size_code INT,
  arch_plate_18_size_code INT,
  arch_plate_31_size_code INT,
  conduit_height FLOAT,
  conduit_width FLOAT,
  number_of_barrels INT,
  roughness_HW FLOAT,
  roughness_DW FLOAT,
  top_radius FLOAT,
  left_slope FLOAT,
  right_slope FLOAT,
  triangle_height FLOAT,
  bottom_radius FLOAT,
  shape_exponent FLOAT,
  us_invert FLOAT,
  ds_invert FLOAT,
  us_headloss_coeff FLOAT,
  ds_headloss_coeff FLOAT,
  Mannings_N FLOAT,
  bottom_mannings_N FLOAT,
  roughness_depth_threshold FLOAT,
  initial_flow FLOAT,
  max_flow FLOAT,
  sediment_depth FLOAT,
  av_headloss_coeff FLOAT,
  seepage_rate FLOAT,
  flap_gate INT,
  culvert_code INT
);

);

The file "opwrowobjectlayoutswmm.xml" is a data file used by the Integrated Urban Water Management Model (ICM) software. The ICM software is used to simulate and analyze the performance of stormwater management systems, including the design and operation of stormwater collection and conveyance systems.

The file "opwrowobjectlayoutswmm.xml" contains variable names specific to the SWMM (Storm Water Management Model) conduit feature in the ICM software. These variable names are used in SQL and Ruby scripts, which are programming languages used to manipulate and analyze the data generated by the ICM software.

The variable names in this file include the definition of the conduit, such as the id, us_node_id, ds_node_id and branch_id; as well as the conduit properties, such as the length, shape, shape_curve, transect, horiz_ellipse_size_code, vert_ellipse_size_code, arch_material, arch_concrete_size_code, arch_steel_half_size_code, arch_steel_inch_size_code, arch_plate_18_size_code, arch_plate_31_size_code, conduit_height, conduit_width, number_of_barrels, roughness_HW, roughness_DW, top_radius, left_slope, right_slope, triangle_height, bottom_radius, shape_exponent, us_invert, ds_invert, us_headloss_coeff, ds_headloss_coeff, Mannings_N, bottom_mannings_N, roughness_depth_threshold, initial_flow, max_flow, sediment_depth, av_headloss_coeff, seepage_rate, flap_gate, culvert_code.

These variable names are used to represent the different attributes of a conduit within the ICM software, and the SQL and Ruby scripts allow users to access and manipulate that data in a variety of ways.

Tuesday, January 17, 2023

SWMM 5.2.2 Code for LID Process in LID.h

 This code defines a struct named "TLidProc" which represents the LID (Low Impact Development) process, which is a generic LID design per unit of area.

The struct contains the following fields:

FieldTypeDescription
IDchar*identifying name of the LID process
lidTypeinttype of LID (corresponds to an enumerator from the "LidTypes" enumeration)
surfaceTSurfaceLayersurface layer parameters
pavementTPavementLayerpavement layer parameters
soilTSoilLayersoil layer parameters
storageTStorageLayerstorage layer parameters
drainTDrainLayerunderdrain system parameters
drainMatTDrainMatLayerdrainage mat layer
drainRmvldouble*underdrain pollutant removals

The "ID" field is a string that can be used to identify the specific LID process. The "lidType" field is an integer that corresponds to one of the enumerators from the "LidTypes" enumeration. This allows the code to determine the specific type of LID process represented by this struct.

The "surface", "pavement", "soil", "storage", "drain" and "drainMat" fields are structs themselves and they contain specific parameters for the surface layer, pavement layer, soil layer, storage layer, underdrain system and drainage mat layer respectively. The "drainRmvl" field is a pointer to an array of doubles, which represent the underdrain pollutant removals.

This struct is used to store all the information about a specific LID process and can be used to design and simulate the performance of the LID unit. The struct also contains information about different layers of LID unit, like surface layer, soil layer and storage layer which helps to simulate the performance of LID unit.


// LID Process - generic LID design per unit of area typedef struct { char* ID; // identifying name int lidType; // type of LID TSurfaceLayer surface; // surface layer parameters TPavementLayer pavement; // pavement layer parameters TSoilLayer soil; // soil layer parameters TStorageLayer storage; // storage layer parameters TDrainLayer drain; // underdrain system parameters TDrainMatLayer drainMat; // drainage mat layer double* drainRmvl; // underdrain pollutant removals } TLidProc;

InfoSWMM: A 2030 AI-Assisted Study Guide

  InfoSWMM: A 2030 AI-Assisted Study Guide delete   InfoSWMM: A 2030 AI-Assisted Study Guide A comprehensive study guide for someone in 2030...