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6 Hierarchical Component Models
source. Three controllers are provided for controlling the source, pump, and heater
(cntrl).
In the problem under consideration, a liquid is a mixture consisting of 25%
kerosene and 75% gasoline in a percentage ratio. The density of kerosene and gasoline
is 760 kg/m
3 and 849 kg/m
3 , respectively. The heat capacities of kerosene and gasoline in the temperature range of interest to us can be approximated by the following
linear functions: for kerosene C p = 446+5.36T and for gasoline C p = 325+4.60T ,
J/(kg K).
The rate of outflow or outflow of fluid from the source, supported by the first
regulator is Q mass1 = 40 kg/s. The pump pumps liquid between the tanks at a speed
supported by the second regulator, equal to Q mass2 = 10 kg/s. The temperature of the
liquid at the initial time T = 300 K. The reservoir 2 is heated using a heating element.
The heat flow rate of the heater supported by the third regulator Q heat = 2.5 × 10
5
J/s.
Since the reservoir is closed, the volume of fluid stored in the reservoir cannot be
greater than its volume.
When controlling the source and pump, two extreme situations must be considered:
(1) the inability to extract fluid from an empty tank;
(2) the inability to add fluid to a completely filled tank.
The tank is supposed to be empty if the mass of liquid in it does not exceed 1 kg.
Tasks
Build a hierarchical component model of the next dynamic system. Two tanks are
initially empty. The operation of the system is defined by the following sequence:
1. From the initial moment of time t = 0 to t 1 = 180 s, the source with the liquid
supplies 1 solution to the tank;
2. At time t 2 = 240 s, the pump turns on and starts pumping liquid from Tank 1 to
Tank 2, and works for 2 min. All that is needed for this is a completely liquid;
3. At time t 3 = 360 s, the heater is turned on, the heated fluid located in the second
tank. The heater runs for 6 min t 4 = 720 s;
4. At t 4 = 720 s, the pump switches on again and starts pumping liquid from the
second tank to the first. The regulator must maintain a constant flow rate for
3 min from t 4 = 720 s to t 5 = 900 s. However, in the second part of the tank, it
is completely empty; further pumping of liquid is impossible;
5. When starting from t 6 = 840 s, the liquid flowing from the first tank back to the
source, work programs end at t 9 = 1200 s.
Independently conduct modeling, simulation, and analysis of this task in the WSM
environment, observing the hierarchical architecture, as shown in Fig. 6.43.
6 Hierarchical Component Models
source. Three controllers are provided for controlling the source, pump, and heater
(cntrl).
In the problem under consideration, a liquid is a mixture consisting of 25%
kerosene and 75% gasoline in a percentage ratio. The density of kerosene and gasoline
is 760 kg/m
3 and 849 kg/m
3 , respectively. The heat capacities of kerosene and gasoline in the temperature range of interest to us can be approximated by the following
linear functions: for kerosene C p = 446+5.36T and for gasoline C p = 325+4.60T ,
J/(kg K).
The rate of outflow or outflow of fluid from the source, supported by the first
regulator is Q mass1 = 40 kg/s. The pump pumps liquid between the tanks at a speed
supported by the second regulator, equal to Q mass2 = 10 kg/s. The temperature of the
liquid at the initial time T = 300 K. The reservoir 2 is heated using a heating element.
The heat flow rate of the heater supported by the third regulator Q heat = 2.5 × 10
5
J/s.
Since the reservoir is closed, the volume of fluid stored in the reservoir cannot be
greater than its volume.
When controlling the source and pump, two extreme situations must be considered:
(1) the inability to extract fluid from an empty tank;
(2) the inability to add fluid to a completely filled tank.
The tank is supposed to be empty if the mass of liquid in it does not exceed 1 kg.
Tasks
Build a hierarchical component model of the next dynamic system. Two tanks are
initially empty. The operation of the system is defined by the following sequence:
1. From the initial moment of time t = 0 to t 1 = 180 s, the source with the liquid
supplies 1 solution to the tank;
2. At time t 2 = 240 s, the pump turns on and starts pumping liquid from Tank 1 to
Tank 2, and works for 2 min. All that is needed for this is a completely liquid;
3. At time t 3 = 360 s, the heater is turned on, the heated fluid located in the second
tank. The heater runs for 6 min t 4 = 720 s;
4. At t 4 = 720 s, the pump switches on again and starts pumping liquid from the
second tank to the first. The regulator must maintain a constant flow rate for
3 min from t 4 = 720 s to t 5 = 900 s. However, in the second part of the tank, it
is completely empty; further pumping of liquid is impossible;
5. When starting from t 6 = 840 s, the liquid flowing from the first tank back to the
source, work programs end at t 9 = 1200 s.
Independently conduct modeling, simulation, and analysis of this task in the WSM
environment, observing the hierarchical architecture, as shown in Fig. 6.43.