tsnet.simulation package

Submodules

tsnet.simulation.initialize module

The tsnet.simulation.initialize contains functions to 1. Initialize the list containing numpy arrays for velocity and head. 2. Calculate initial conditions using Epanet engine. 3. Calculate D-W coefficients based on initial conditions. 4. Calculate demand coefficients based on initial conditions.

tsnet.simulation.initialize.Initializer(tm, t0, engine='DD')

Initial Condition Calculation.

Initialize the list containing numpy arrays for velocity and head. Calculate initial conditions using Epanet engine. Calculate D-W coefficients based on initial conditions. Calculate demand coefficients based on initial conditions.

Parameters:

• tm (tsnet.network.geometry.TransientModel) – Simulated network
• t0 (float) – time to calculate initial condition
• engine (string) – steady state calculation engine: DD: demand driven; PDD: pressure dependent demand, by default DD

Returns:

tm – Network with updated parameters

Return type:

tsnet.network.geometry.TransientModel

tsnet.simulation.initialize.cal_demand_coef(demand, pipe, Hs, He, t0=0.0)

Calculate the demand coefficient for the start and end node of the pipe.

Parameters:

• demand (list) – Demand at the start (demand[0]) and end demand[1] node
• pipe (object) – Pipe object
• Hs (float) – Head at the start node
• He (float) – Head at the end node
• t0 (float, optional) – Time to start initial condition calculation, by default 0

Returns:

pipe – Pipe object with calculated demand coefficient

Return type:

object

tsnet.simulation.initialize.cal_roughness_coef(pipe, V, hl)

Calculate the D-W roughness coefficient based on initial conditions.

Parameters:

• pipe (object) – Pipe object
• V (float) – Initial flow velocity in the pipe
• hl (float) – Initial head loss in the pipe

Returns:

pipe – Pipe object with calculated D-W roughness coefficient.

Return type:

object

tsnet.simulation.main module

The tsnet.simulation.main module contains function to perform the workflow of read, discretize, initial, and transient simulation for the given .inp file.

tsnet.simulation.single module

The tsnet.simulation.single contains methods to perform MOC transient simulation on a single pipe, including 1. inner pipe 2. left boundary pipe (without C- charateristic grid) 3. right boundary pipe (without C+ characteristic grid)

tsnet.simulation.single.inner_pipe(linkp, pn, dt, links1, links2, utype, dtype, p, H0, V0, H, V, H10, V10, H20, V20, pump, valve)

MOC solution for an individual inner pipe.

Parameters:

• linkp (object) – Current pipe object
• pn (int) – Current pipe ID
• dt (float) – Time step
• H (numpy.ndarray) – Head of current pipe at current time step [m]
• V (numpy.ndarray) – Velocity of current pipe at current time step [m/s]
• links1 (list) – Upstream adjacent pipes
• links2 (list) – Downstream adjacent pipes
• utype (list) – Upstream adjacent link type, and if not pipe, their name
• dtype (list) – Downstream adjacent link type, and if not pipe, their name
• p (list) – pipe list
• n (int) – Number of discretization of current pipe
• H10 (list) – Head of left adjacent nodes at previous time step [m]
• V10 (list) – Velocity of left adjacent nodes at previous time step [m/s]
• H20 (list) – Head of right adjacent nodes at previous time step [m]
• V20 (list) – Velocity of right adjacent nodes at previous time step [m/s]
• pump (list) – Characteristics of the pump
• valve (list) – Characteristics of the valve

Returns:

• H (numpy.ndarray) – Head results of the current pipe at current time step. [m]
• V (numpy.ndarray) – Velocity results of the current pipe at current time step. [m/s]

tsnet.simulation.single.left_boundary(linkp, pn, H, V, H0, V0, links2, p, pump, valve, dt, H20, V20, utype, dtype)

MOC solution for an individual left boundary pipe.

Parameters:

• linkp (object) – Current pipe object
• pn (int) – Current pipe ID
• H (numpy.ndarray) – Head of current pipe at current time step [m]
• V (numpy.ndarray) – Velocity of current pipe at current time step [m/s]
• links2 (list) – Downstream adjacent pipes
• p (list) – pipe list
• pump (list) – Characteristics of the pump
• valve (list) – Characteristics of the valve
• n (int) – Number of discretization of current pipe
• dt (float) – Time step
• H0 (numpy.ndarray) – Head of current pipe at previous time step [m]
• V0 (numpy.ndarray) – Velocity of current pipe at previous time step [m/s]
• H20 (list) – Head of right adjacent nodes at previous time step [m]
• V20 (list) – Velocity of right adjacent nodes at previous time step [m/s]
• utype (list) – Upstream adjacent link type, and if not pipe, their name
• dtype (list) – Downstream adjacent link type, and if not pipe, their name

Returns:

• H (numpy.ndarray) – Head results of the current pipe at current time step. [m]
• V (numpy.ndarray) – Velocity results of the current pipe at current time step. [m/s]

tsnet.simulation.single.right_boundary(linkp, pn, H0, V0, H, V, links1, p, pump, valve, dt, H10, V10, utype, dtype)

MOC solution for an individual right boundary pipe.

Parameters:

• linkp (object) – Current pipe object
• pn (int) – Current pipe ID
• H (numpy.ndarray) – Head of current pipe at current time step [m]
• V (numpy.ndarray) – Velocity of current pipe at current time step [m/s]
• links1 (list) – Upstream adjacent pipes
• p (list) – pipe list
• pump (list) – Characteristics of the pump
• valve (list) – Characteristics of the valve
• n (int) – Number of discretization of current pipe
• dt (float) – Time step
• H0 (numpy.ndarray) – Head of current pipe at previous time step [m]
• V0 (numpy.ndarray) – Velocity of current pipe at previous time step [m/s]
• H10 (list) – Head of left adjacent nodes at previous time step [m]
• V10 (list) – Velocity of left adjacent nodes at previous time step [m/s]
• utype (list) – Upstream adjacent link type, and if not pipe, their name
• dtype (list) – Downstream adjacent link type, and if not pipe, their name

Returns:

• H (numpy.ndarray) – Head results of the current pipe at current time step. [m]
• V (numpy.ndarray) – Velocity results of the current pipe at current time step. [m/s]

tsnet.simulation.solver module

The tsnet.simulation.solver module contains methods to solver MOC for different grid configurations, including: 1. inner_node 2. valve_node 3. pump_node 4. source_pump 5. valve_end 6. dead_end 7. rev_end 8. add_leakage

tsnet.simulation.solver.inner_node(link1, link2, demand, H1, V1, H2, V2, dt, g, nn, s1, s2)

Inner boundary MOC using C+ and C- characteristic curve

Parameters:

• link1 (object) – Pipe object of C+ charateristics curve
• link2 (object) – Pipe object of C- charateristics curve
• demand (float) – demand at the junction
• H1 (list) – List of the head of C+ charateristics curve
• V1 (list) – List of the velocity of C+ charateristics curve
• H2 (list) – List of the head of C- charateristics curve
• V2 (list) – List of the velocity of C- charateristics curve
• dt (float) – Time step
• g (float) – Gravity acceleration
• nn (int) – The index of the calculation node
• s1 (list) – List of signs that represent the direction of the flow in C+ charateristics curve
• s2 (list) – List of signs that represent the direction of the flow in C- charateristics curve

Returns:

• HP (float) – Head at current node at current time
• VP (float) – Velocity at current node at current time

tsnet.simulation.solver.valve_node(KL_inv, link1, link2, H1, V1, H2, V2, dt, g, nn, s1, s2)

Inline valve node MOC calculation

Parameters:

• KL_inv (int) – Inverse of the valve loss coefficient at current time
• link1 (object) – Pipe object of C+ charateristics curve
• link2 (object) – Pipe object of C- charateristics curve
• H1 (list) – List of the head of C+ charateristics curve
• V1 (list) – List of the velocity of C+ charateristics curve
• H2 (list) – List of the head of C- charateristics curve
• V2 (list) – List of the velocity of C- charateristics curve
• dt (float) – Time step
• g (float) – Gravity acceleration
• nn (int) – The index of the calculation node
• s1 (list) – List of signs that represent the direction of the flow in C+ charateristics curve
• s2 (list) – List of signs that represent the direction of the flow in C- charateristics curve

tsnet.simulation.solver.pump_node(pumpc, link1, link2, H1, V1, H2, V2, dt, g, nn, s1, s2)

Inline pump node MOC calculation

Parameters:

• pumpc (list) – Parameters (a, b,c) to define pump characteristic cure, so that .. math:: h_p = a*Q**2 + b*Q + c
• link1 (object) – Pipe object of C+ charateristics curve
• link2 (object) – Pipe object of C- charateristics curve
• H1 (list) – List of the head of C+ charateristics curve
• V1 (list) – List of the velocity of C+ charateristics curve
• H2 (list) – List of the head of C- charateristics curve
• V2 (list) – List of the velocity of C- charateristics curve
• dt (float) – Time step
• g (float) – Gravity acceleration
• nn (int) – The index of the calculation node
• s1 (list) – List of signs that represent the direction of the flow in C+ charateristics curve
• s2 (list) – List of signs that represent the direction of the flow in C- charateristics curve

tsnet.simulation.solver.source_pump(pump, link2, H2, V2, dt, g, s2)

Source Pump boundary MOC calculation

Parameters:

• pump (list) – pump[0]: elevation of the reservoir/tank pump[1]: Parameters (a, b,c) to define pump characteristic cure, so that .. math:: h_p = a*Q**2 + b*Q + c
• link2 (object) – Pipe object of C- charateristics curve
• H2 (list) – List of the head of C- charateristics curve
• V2 (list) – List of the velocity of C- charateristics curve
• dt (float) – Time step
• g (float) – Gravity acceleration
• s2 (list) – List of signs that represent the direction of the flow in C- charateristics curve

tsnet.simulation.solver.valve_end(H1, V1, V, nn, a, g, f, D, dt)

End Valve boundary MOC calculation

Parameters:

• H1 (float) – Head of the C+ charateristics curve
• V1 (float) – Velocity of the C+ charateristics curve
• V (float) – Velocity at the valve end at current time
• nn (int) – The index of the calculation node
• a (float) – Wave speed at the valve end
• g (float) – Gravity acceleration
• f (float) – friction factor of the current pipe
• D (float) – diameter of the current pipe
• dt (float) – Time step

tsnet.simulation.solver.dead_end(linkp, H1, V1, nn, a, g, f, D, dt)

Dead end boundary MOC calculation with pressure dependant demand

Parameters:

• link1 (object) – Current pipe
• H1 (float) – Head of the C+ charateristics curve
• V1 (float) – Velocity of the C+ charateristics curve
• nn (int) – The index of the calculation node
• a (float) – Wave speed at the valve end
• g (float) – Gravity acceleration
• f (float) – friction factor of the current pipe
• D (float) – diameter of the current pipe
• dt (float) – Time step

tsnet.simulation.solver.rev_end(H2, V2, H, nn, a, g, f, D, dt)

Reservoir/ Tank boundary MOC calculation

Parameters:

• H2 (list) – List of the head of C- charateristics curve
• V2 (list) – List of the velocity of C- charateristics curve
• H (float) – Head of the reservoir/tank
• nn (int) – The index of the calculation node
• a (float) – Wave speed at the valve end
• g (float) – Gravity acceleration
• f (float) – friction factor of the current pipe
• D (float) – diameter of the current pipe
• dt (float) – Time step

tsnet.simulation.solver.add_leakage(emitter_coef, link1, link2, elev, H1, V1, H2, V2, dt, g, nn, s1, s2)

Leakage Node MOC calculation

Parameters:

• emitter_coef (float) – float, optional Required if leak_loc is defined The leakage coefficient of the leakage .. math:: Q_leak = leak_A [ m^3/s/(m H20)^(1/2)] * sqrt(H)
• link1 (object) – Pipe object of C+ charateristics curve
• link2 (object) – Pipe object of C- charateristics curve
• H1 (list) – List of the head of C+ charateristics curve
• V1 (list) – List of the velocity of C+ charateristics curve
• H2 (list) – List of the head of C- charateristics curve
• V2 (list) – List of the velocity of C- charateristics curve
• dt (float) – Time step
• g (float) – Gravity acceleration
• nn (int) – The index of the calculation node
• s1 (list) – List of signs that represent the direction of the flow in C+ charateristics curve
• s2 (list) – List of signs that represent the direction of the flow in C- charateristics curve

Module contents

The tsnet.simulation package contains methods to run transient simulation using MOC method