Rhythmic and controlled fountains

Rhythmic and controlled fountains

Designing movement patterns, selecting equipment and managing daily performance

A rhythmic fountain creates a moving image by programmed change in the height, sequence, direction or shape of the water discharge. The movement can be slow and continuous, go in waves along the fountain or create geometric compositions by alternating activation of different groups.

This type of fountain can be performed without music and behave differently at different times of the day, according to the use of the environment. In an urban square, the regular movement of water may be part of the visual identity of the space; In the commercial area, a short program can attract the attention of passers-by; And in the sitting space, quiet changes can accompany people's daily activities.

A successful design is formed when the desired patterns, the actual power of the equipment and the operating conditions are in harmony with each other from the beginning.

8–1. The difference between rhythmic, controlled and musical fountains

Common industry terms are not always used with the same meaning. To avoid ambiguity, the following definitions are used in this book:

These features can exist simultaneously in a project. For example, a controlled fountain can perform a rhythmic program throughout the day and a musical show at a certain time.

Also, "automatic control" does not necessarily mean "animated display". A water feature that turns on only on the clock and has a fixed height is automatic in operation, but does not necessarily create a rhythmic display.

On the GSO website, rhythmic and musical projects are also introduced in separate groups, and control equipment is provided for different types of fountains. Source: Introduction of GSO urban fountains ^[42]

8–2. What features can be controlled?

Before selecting the controller, it should be determined which physical properties are to be changed.

The four main areas are:

Activity time: determining when each nozzle or group will be activated and how long it will remain in the desired state.

Output intensity: change in flow rate, pressure or speed of water output, which, according to the type of nozzle and circuit, can affect the height and shape of the effect.

Direction and geometry: changing the angle of the nozzle, the direction of the launch or the shape of the outlet with the help of a suitable mechanism.

Light: Change the intensity, color and sequence of lighting to accompany the movement of the water.

These features should be checked for each device separately. A nozzle that only has the ability to connect and disconnect, is not able to continuously adjust the height by itself. Also, the controllability of the pump does not mean that the direction of the nozzle is movable.

An example of output geometry control is OASE's VarioMaster nozzle, for which the manufacturer introduces motorized water shape change and DMX controllability. This feature depends on the structure of the same product. Source: Introduction of VarioMaster in OASE ^[43]

8–3. Number of nozzles and independence of control

One of the most important design decisions is determining the number of independent units.

Suppose two fountains have 24 nozzles each:

• In the first fountain, all nozzles are fed from a common circuit without independent adjustment.

• In the second fountain, the nozzles are in six independent groups.

• In the third fountain, each nozzle has an independent controllable outlet.

All three designs may look similar in a still photo, but their capacity to create movement is different.

To clarify this issue, two concepts should be distinguished:

Physical group: nozzles that share a common behavior due to their hydraulic structure or steering equipment.

Software Group: A collection of independent equipment that temporarily receives a common command in the program.

If each nozzle is independent, even and odd nozzles can be grouped today and symmetrical groups can be made in another program. But if two nozzles are in a physical group without independent control, the software alone cannot separate their behavior from each other.

Therefore, in the purchase documents, the phrase "24 control nozzles" should be completed by specifying the type of control, the number of independent outlets and the grouping limit.

Figure note from the source manuscript

Figure 1-8: Comparison diagram of a 12-nozzle arrangement in three modes: joint control, six two-nozzle groups, and independent control of each nozzle. Suggested caption: "The number of independent units determines the range of viable patterns." The image should be prepared as an educational schematic.

8–4. Basic movement patterns

A large part of the rhythmic programs is made by combining a few simple patterns.

More speed doesn't always mean more readability. If the changes are faster than the equipment can respond, the audience may see a jumble of pitch and splatter instead of a clear sequence.

The pattern should be checked from the actual location of the viewer. A movement that is clear in the top view may be hidden from the view of the passerby behind the front rows.

8–5. Educational example: wave design in six groups

Suppose a fountain has 12 independent nozzles. For a specific application, nozzles are divided into six two-nozzle software groups:

Each group performs a smooth, repeatable change in output. If the full period of this change is 6 seconds and we want the phase difference between the six groups to be equal:

Time difference of adjacent groups = full period ÷ number of groups

6 ÷ 6 = 1 second

As a result, the pattern of groups 2 to 6 is executed with a difference of one to five seconds compared to the first group, respectively. After six seconds, the cycle will repeat.

This example shows the desired pattern timing. To achieve the same result in real water, the response of pumps, valves, and circuits must be measured and factored into the program.

If the equipment is only disconnected and connected, the result is a step sequence. Creating a smooth wave in height requires continuous adjustability and proper response of the equipment.

Figure note from the source manuscript

Figure 2–8: Six similar curves with a one-second time shift, along with a few frames of the desired water shape during the cycle. Suggested subtitle: "A rhythmic wave is formed by the execution of a common pattern with a time difference between groups." The numbers are educational.

8–6. Choosing between variable speed pump, control valve and moving mechanism

The choice of equipment should start from the intended behavior.

To continuously change the height, a variable speed pump or a suitable flow adjustment method can be used. The quality of the result depends on the operating range of the pump, the characteristics of the nozzle and the behavior of the circuit. In GSO products, the group of control pumps and variable speed has been introduced. Source: GSO urban fountain control pumps ^[44]

To quickly disconnect and connect the effect, you should choose a device that is designed for the same type of function. For example, Crystal Fountains introduces ChoreoSwitch nozzles to run programmed sequences and explains the height change in combination with a variable displacement pump. This example shows that exit time control and altitude control can be separate tasks. Source: SWS ChoreoSwitch nozzle ^[45]

A suitable moving mechanism is required to change direction or shape. In this case, the range of movement, the allowed speed, the reference position and the path of water descent should also be specified.

Sometimes a combination of these equipments gives the best answer: a pump to adjust the output, a valve for rapid sequence and a moving mechanism to change the direction. This combination should be designed in terms of hydraulic, electrical and integrated control.

8–7. The relationship between the control command and the actual height of the water

The command value is a control number; Water height, the physical result of the operation of the set of equipment.

The 50% command does not necessarily create a height equal to half the maximum height. The relationship between the distance, flow rate, head and output height depends on the specifications of the pump, nozzle and network.

Similarity laws of pumps also express the relationship between the change in speed and the changes in flow rate, head and power under certain conditions; These relationships alone are not a substitute for examining the operating point and actual behavior of the circuit. Source: pump similarity rules in KSB technical reference ^[46]

For more accurate planning, the command-result relationship should be measured within the allowable range of work. The calibration table can include:

• command value;

• The height or stable shape of the outlet;

• time to reach the desired state;

• measurement conditions, including water level and status of other groups;

• Observed limitations.

In the common circuit, this check should be done for effective combinations; Because the opening or closing of other groups may change the output of a nozzle.

8–8. Checking the circuit in different execution modes

Designing a rhythmic water feature requires consideration of several work situations. "All outputs on" mode is not the only important mode.

For a shared circuit, at least the following related modes should be considered:

• Simultaneous activity of all authorized groups;

• Activity of the least number of groups;

• change from one composition to another;

• Reduction of output in calm state or wind restriction;

• Stop and start according to the designed sequence.

In any case, the total output flow is equal to the sum of the actual flow of the branches; But the flow rate of each branch may be changed by changing the pressure of the circuit. Therefore, collecting the nominal flow rates without checking the working conditions is not enough to select the pump.

Also, the closing of the outlets should not put the pump or the network into an illegal state. Necessity of bypass path, circuit change, valve operation sequence or other solution should be determined in mechanical design.

In programming, the allowed combinations should be clear so that changing a program does not violate the limits of the circuit.

8–9. Movement speed and frequency of performance

In the rhythmic fountain, in addition to the working hours, the number of times the performance of some parts is important.

Let's say a valve makes a full cycle of opening and closing every 4 seconds and this pattern continues for 8 hours a day:

Number of daily cycles = working time in seconds ÷ time of each cycle

8 × 3600 ÷ 4 = 7200 cycles per day

This value is not the data of a specific product; An example is to show the effect of the demonstration program on the performance of the equipment. In this example, the complete cycle consists of an opening and a closing. When comparing with the manufacturer's information, it should be clarified whether the declared life is based on "cycles" or "number of operations".

To select the equipment, the speed limit, continuous or intermittent operation, water conditions and service needs should be checked.

Also, changing the output through the control command is different from connecting and disconnecting the main power of the equipment. The device may be designed for frequent output changes, but have another limitation for frequent electrical start-ups.

8–10. Daily schedule and operating modes

An urban fountain may be active for many hours. For such an application, it is useful to design a few distinct modes:

The transition between modes is also part of the design. A sudden change from a quiet program to maximum output may not be compatible with the desired behavior of the circuit or the visual experience of the space.

It should be determined which state the system will go to in case of power or communication return and what conditions are necessary to start again. The operator's manual command must also operate within the defined protection limits.

8–11. Lighting with the rhythm of water

In a rhythmic fountain, light can make movement clearer. For example, the sequential activation of water groups can be accompanied by a gradual shift in brightness.

The three practical methods are:

Light in line with movement: The color or intensity of light changes with the sequence of water.

Steady light with changing water: Steady light keeps the focus on the shape and movement of the water.

Different layers: one group plays the role of light background and the other group creates the main movement.

The choice of method should be compatible with the architecture of the environment. Changing all colors in succession can reduce the readability of the water pattern; Especially when the buildings, signs and surrounding lighting are also diverse.

It is better to evaluate the day and night program separately. An effect that is legible at night with the help of light, may require a change of makeup or range of motion during the day.

Figure note from the source manuscript

Figure 3–8: Three consecutive frames from a real GSO project, with a fixed camera angle and showing changing water and light. Suggested Caption: "Sequences of images show the rhythmic behavior of a fountain better than a single photo." The frames are preferably extracted from a movie and with a certain time interval.

8–12. Energy and operating cost

Controllability can allow adjustment of operating hours and output intensity, but the amount of savings must be calculated based on actual performance.

To estimate the energy of several work modes, we can write:

Energy consumption = the sum of the average power of each mode x the duration of that mode

If power is entered in kilowatts and time in hours, the result will be in kilowatt hours.

The measurement boundary should be clear in the calculation: are only the pumps considered or are the lighting, control, treatment and ancillary equipment also considered?

For the variable display, the rated power of the motor is not necessarily equal to the average power consumption. Recording consumption in actual program execution provides a more appropriate basis for evaluating utilization.

The cost of maintenance should also be seen along with energy. An application with a large number of functions may have different service requirements than a quiet application. Choosing a routine should strike a balance between visual quality, consumption, and equipment life.

8–13. Delivery and acceptance criteria

For a rhythmic fountain, delivery should be based on specific and testable patterns.

Acceptance limits must be agreed upon prior to implementation. For example, "smooth movement" should be defined with a reference program and appropriate observation or measurement method so that the assessment is not dependent on individual taste alone.

8–14. Maintenance and modification of programs

The quality loss in the rhythmic fountain is sometimes seen before the complete stop of the equipment: one group rises later, two nozzles of the same group have different heights, or the symmetrical movement has become asymmetrical.

For review, the possibility of change should be considered in all three areas:

Mechanics and hydraulics: clogging, change of nozzle setting, valve condition, pump operation or water level.

Power and communication: Power status, connections, drive and steering transmission.

Program and settings: addressing, scheduling, output limit and program version.

Changing the software to hide a mechanical fault can make the problem more difficult to diagnose. First, the cause should be determined and then the necessary adjustments should be made.

Having a short and consistent test schedule, along with results recorded when delivered, helps to compare the status of different courses.

Figure note from the source manuscript

Figure 4–8: A technical photo of setting up nozzles or checking equipment on an actual project, along with an overview of the same fountain. Suggested subtitle: "Maintaining the order of the movement depends on the health of the equipment, correct adjustment and periodic performance control."

A rhythmic fountain can have a continuous presence and suit the daily life of the city. Its quality is obtained from the right selection of independent units, design of readable patterns and reliable execution over time.

In Chapter 9, dry floor fountains are examined; Fountains where coordination between hidden equipment, flooring, water collection and the way people are present in them play a decisive role.