Principle of the Venturi Nozzle

A Venturi injector is based on the Venturi nozzle invented by Giovanni Battista Venturi over 200 years ago: This is a smooth-walled tube with a sharp constriction in the center, from which an opening leads downwards. At the constricted point in the tube, due to the laws of physics, the velocity of the water flowing through it increases (= increasing flow pressure), while at the same time the static pressure on the tube wall decreases; total pressure = flow pressure + static pressure. The constriction in a Venturi nozzle is designed so large that the static pressure at the constriction not only decreases, but even creates a negative pressure (vacuum). This means that no water escapes from the opening leading away from the constriction; on the contrary, a suction is created.

How a Venturi Injector Works

The suction created by the flow through the Venturi nozzle is used to draw in a gas or liquid via a hose mounted at the constriction. In the application described here, liquid fertilizer is drawn in. For this purpose, the hose is simply led away from the Venturi nozzle into a container containing fertilizer. As soon as irrigation is running, the created suction ensures that the fertilizer is gradually mixed into the irrigation water.

At the opening from which the fertilizer intake hose leads, a mechanism is installed in the Venturi nozzle that prevents water from flowing into the fertilizer container. In practice, this would occur when irrigation is stopped, thus creating pressure at the intake opening instead of a negative pressure. The water remaining in the irrigation system would then be forced outward and flow into the fertilizer container.

In most Venturi injectors, the backflow prevention mechanism works with a small spring that pushes a plastic ball in front of the outlet, thus closing it. Only when sufficient suction is applied does the ball retract, opening the outlet so that the fertilizer can be drawn in.

Intake outlet ready for use and below with removed seal, ball and spring

The ratio of fertilizer addition is primarily determined by the following three parameters:

• Diameter of the Venturi nozzle and the nozzle constriction
• Inlet pressure at the inlet of the Venturi nozzle
• Outlet pressure at the outlet of the Venturi nozzle

The following applies: The greater the pressure difference between the inlet pressure (at the inlet of the nozzle) and the outlet pressure (at the outlet of the nozzle, after passing the constriction), the greater the suction effect and, consequently, the more fertilizer is added. This difference is achieved, on the one hand, by the constriction in the Venturi nozzle, as the water loses pressure due to the strong friction when passing through the constriction. The narrower the constriction, the greater the pressure loss. When installing the Venturi nozzle via a pipe bypass, the pressure difference can be further increased by deliberately slowing the water flow upstream of the outlet side of the Venturi nozzle with a valve, allowing the fertilizer dosage to be controlled according to your preferences.

Depending on the model, Venturi injectors require at least a 20 to 30% pressure difference between the inlet and outlet of the nozzle to function. A difference of around 50% typically achieves the maximum possible fertilizer dosage. The minimum pressure difference required to draw in fertilizer cannot be achieved with all Venturi injectors and at all inlet pressures using only the Venturi nozzle; in some cases, creating an additional pressure difference using a bypass is absolutely necessary.

The maximum technically achievable mixing rate for a Venturi injector is a maximum of 10% (i.e., 1 gallon of fertilizer to 10 gallons of water). For the sake of completeness: In addition to the size and design of the Venturi nozzle, the inlet and outlet pressures, other factors can have a minor impact on the dosage ratio: the liquid fertilizer used (viscous or watery), how deep the fertilizer container is placed below the nozzle, the outside temperature, and the elevation of the application site.

The diameter of the Venturi nozzle, the inlet pressure, and the outlet pressure also determine how many gallons of water per hour can flow through the nozzle in this configuration. Quality manufacturers list these parameters for each nozzle size and different inlet and outlet pressures in performance tables. Below is the example performance table for Irritec’s Venturi injectors:

Performance table of Irritec Venturi injectors

The first column shows the inlet pressure, followed by a range of possible outlet pressures. For each combination of inlet and outlet pressure, the corresponding water flow and fertilizer output are listed. This is for four different Venturi injector models ranging in size from 3/4 inch to 2 inches.

An example explains how to read such a table:

Using a 3/4-inch injector, an inlet pressure of 4.10 bar (60 psi), and an outlet pressure of 3.0 bar (43 psi), a flow of 36 liters per minute (10 gallons per minute) or 2,160 liters per hour (570 gallons per hour) is possible, and the fertilizer addition would be 66 liters (17 gallons) per hour. With a 1-inch injector, the water flow at the same pressure would be 4,560 liters per hour (1.200 gallons), and the fertilizer addition would be 230 liters (60 gallons).

What determines the outlet pressure?

The outlet pressure is determined by the requirements you want to meet with the fertilizer water. If the water were simply allowed to flow freely out of the pipe immediately after leaving the Venturi nozzle, a pressure close to zero on the outlet side would be sufficient. In this case, a valve installed in the bypass could reduce this pressure to near zero, thus exploiting the maximum possible pressure difference and achieving the highest possible fertilizer dosage.

However, if the fertilizer water still has to exert considerable pressure after leaving the Venturi nozzle – as is usually necessary in an irrigation system – to travel the distance through the irrigation pipeline and then ensure the sprinklers extend and function correctly, a significantly higher pressure is required on the outlet side.

This is essentially the same consideration as when calculating the water flow rate in an irrigation system. For example, if the sprinklers require 40 psi and there is a further pressure loss of 10 psi in the pipeline due to friction, then 50 psi of pressure would be needed on the outlet side just to exert the necessary static pressure in the irrigation system. At such a pressure, however, the entire output pressure would be used for static pressure, leaving no dynamic pressure to drive the water through the pipes. For irrigation to function with a reasonable amount of water, a slightly higher output pressure than 50 psi would be required. According to a practical example used here in the blog, for example, with the water source used there, you would need 60 psi to achieve a water output of 280 gallons per hour with a pressure requirement of 50 psi in the irrigation system.

This shows that in practice, you have to weigh and balance between higher fertilizer dosage and still sufficient output pressure, and in many cases, you will have to focus on the lowest possible dosage. Unless you use the Venturi injector for micro-irrigation, which has significantly lower pressure requirements, or you have a very powerful pump available that still has considerable reserves for everyday irrigation needs.

Advantages and Disadvantages of Fertilization with a Venturi Injector

The main advantage of fertilization with a Venturi injector is that it is very easy and cost-effective to implement. Furthermore, Venturi injectors are simple and have no moving parts, so almost nothing can break during operation and they are therefore very low-maintenance.

A significant disadvantage is that the Venturi nozzle relies on the existing water pressure to function. Bernoulli’s law “Total pressure = flow pressure + static pressure” only applies one-to-one to frictionless fluids, which water is not. Therefore, when water flows through the constriction of the Venturi nozzle, friction losses occur and, consequently, pressure losses. The function of the Venturi nozzle is based precisely on this pressure loss, which leads to the pressure difference.

Depending on the nozzle model, a pressure drop of at least 20 to 25% is required for proper functioning. If the natural pressure loss through the nozzle is insufficient, the water must be additionally slowed down in a bypass system with a valve.

Consequently, the use of a Venturi injector leads to a certain pressure loss, so that the pressure ratios previously present in an irrigation system are no longer 1:1, and irrigation may then no longer function as perfectly as before (reduced uniformity). It is comparatively easy to use in micro-irrigation systems, which operate at low pressure. Therefore, reducing the pressure hardly plays a role in such systems.

For use in conventional irrigation, e.g., for watering the lawn, a powerful pump is advantageous, so that sufficient pressure remains for irrigation after the water has passed through the Venturi nozzle, and irrigation continues to function properly.

Compared to fertilizer systems with a dosing pump, a Venturi injector also has the disadvantage that the amount of fertilizer delivered depends on the pressure conditions. This makes it difficult to precisely adjust and maintain the fertilizer dosage, especially if the irrigation system is subject to fluctuating pressure conditions.

Finally, correctly adjusting the Venturi injector for the first time requires some effort, especially if you want to set the dosage to a predetermined level. After setup, the installation is ideally left untouched so that the desired adjustment can be used permanently.

How to Install the Venturi Injector

The Venturi Injector is typically installed in the main pipeline, i.e., in the section of the pipe at the beginning of the system that is passed through during each irrigation run, before the main line then splits into several branches for the individual irrigation sectors.

To prevent the risk of backflow of water mixed with fertilizer toward the water source, a backflow valve should be installed between the water source and the fertilization system, or the Venturi nozzle should be isolated from the main system with manual valves after fertilization. If drinking water is used directly from the drinking water system, the stricter regulations regarding drinking water protection must be observed.

The Venturi Injector can either be installed in-line with the main pipeline or in a branch (bypass) that diverts from the main pipeline to the Venturi Injector and returns to the main pipeline after the fertilizer has been absorbed.

Such a bypass installation has the following advantages:

• With a valve installed in the main line at the level of the bypass between the bypass inlet and bypass outlet, you can control the pressure difference between the inlet pressure and the outlet pressure of the Venturi nozzle, thus adjusting the fertilizer dosage. Some manufacturers even specify this type of installation to ensure their injector functions properly, or even strongly recommend it, because the Venturi nozzle alone cannot create the necessary pressure difference, or not in every pressure configuration.
• Furthermore, a bypass solution has a positive effect on water flow, as some of the water can bypass the Venturi nozzle and take the direct route through the pipeline. This enables higher flow rates than the Venturi nozzle itself would allow.
• The bypass can be deactivated relatively easily with valves installed in between, so that during normal non-fertilizer irrigation runs, the water does not have to flow through the Venturi nozzle. If the injector were installed directly into the main line, it would have to be removed every time after use to achieve the same result. The bypass, on the other hand, only needs to be installed once and can then remain as it is permanently.

Below are four possible installation methods for a Venturi injector from the Irritec user manual. In addition to the connection directly into the pipeline and the standard bypass connection, two alternative connections with an additional pump are also listed:

Four possible installation types

The Venturi injector should always be mounted horizontally or, alternatively, vertically upward (i.e., inlet at the bottom and outlet at the top). A vertically downward position can cause suction problems. The water must flow through the nozzle in the specified direction; this direction is indicated on the nozzle.

By installing a pressure gauge on the inlet and outlet sides of the bypass, the inlet and outlet pressure can always be precisely monitored, or a specific pressure difference can be set using a valve.

Since airtight connections are important for proper operation, it is recommended to use PE tape or other sealing material on the threads during installation. Ideally, the complete injector, i.e., both the nozzle and the suction hose, should be purchased from the same manufacturer to ensure optimal compatibility.

The suction hose is suspended completely down to the bottom of the fertilizer tank so that the fertilizer can be drawn all the way to the bottom. At the end of the suction hose there is usually a small filter basket that prevents the suction of larger protective particles.

How to Choose a Suitable Venturi Injector

The most important selection criterion is the size of the injector! This is not determined by the size of the pipeline used in the irrigation system, but by the available pressure and water flow rate. Specifically, the water flow rate achieved during operation, not the maximum available! This is further exacerbated by the fact that the Venturi nozzle requires a significant pressure reduction of 20% or more to function, and the water flow rate when using a Venturi nozzle will therefore be somewhat lower than in previous irrigation runs without a Venturi nozzle. Unless you haven’t yet fully utilized the potential pump capacity or the power from the domestic water supply, so you still have some reserves.

If in doubt, or if you’re unsure about the water flow rate, it’s better to buy a smaller Venturi injector!

If the injector is too large and the specified flow rate is not reached, the injector will not draw in any fertilizer. If the injector is too small, however, fertilization will work perfectly, but the injector will limit the flow. This problem can be solved relatively easily by incorporating it into a bypass so that excess water can bypass the nozzle.

Note: Micro-irrigation sectors are particularly problematic for Venturi injectors if they have very low water flow rates. Here, you must carefully find a suitable injector or, if that is not possible, use a different fertilization system altogether.

Regarding water flow, it is important to note that even with the same diameter, Venturi injectors can have very different performance characteristics. There are 3/4-inch injectors designed for high water flow and others for low water flow. The manufacturer Mazzei, for example, offers both the IM34L model with a minimum flow rate of 240 gallons/hour at 50 psi inlet pressure and the IM34H model with a minimum flow rate of 420 gallons/hour at 50 psi inlet pressure in 3/4-inch sizes. They also offer a 1/2-inch injector with a low flow rate of 60 gallons/hour or a high flow rate of 150 gallons/hour (IM12L and IM12H). The 3/4-inch Irritec model I tested requires approximately 500 gallons/hour at an inlet pressure of 50 psi.

The possible fertilizer dosage is only a secondary selection criterion. Liquid fertilizer manufacturers specify a specific dosage ratio for their products, which the injector should be able to achieve. However, it is particularly important not to apply the fertilizer too concentrated, as this could damage the plants. However, this problem will rarely occur with Venturi injectors, as higher dosages require more pressure. When fertilizing with an irrigation system, it is generally recommended to apply the fertilizer slowly, as this allows for greater uniformity.

Products Available on the Market

Complete Venturi injectors, consisting of a nozzle and intake hose, as well as nozzles and intake hoses separately, are available on the market. Venturi injectors are available either as a standalone product, i.e., just the nozzle and a matching intake hose, or as part of a pre-assembled bypass. This saves you the trouble of assembling such a bypass yourself.

Numerous no-name products are available, as well as products from brand manufacturers such as Netafim, Irritec, or Mazzei. No-name Venturi injectors start at $20 to $30, while brand-name products cost approximately $60 to $100. A Venturi injector in a pre-assembled bypass solution will cost approximately $30 to $200 more, depending on the quality of the bypass and whether it includes a built-in pressure gauge. Some injectors also offer a way to adjust the dosage by using a valve on the intake hose to slow the suction.

Venturi injectors on Amazon:

Unlorspy 2Pcs Black Venturi Injector Tube 1/2 Inch Agriculture Garden Fertilizer Injector Plastic Irrigation Venturi Injector for Irrigation Systems (1/2 Inch)

$9.69 (as of 17. March 2026 16:04 GMT +01:00 - More infoProduct prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on [relevant Amazon Site(s), as applicable] at the time of purchase will apply to the purchase of this product.)

AYLIFU 3/4Inch Black Irrigation Venturi Fertilizer Injector Tube Venturi Fertilizer Mixer Injector for Outdoor Garden Agricultural Irrigation Equipment Tools

$8.99 (as of 17. March 2026 16:04 GMT +01:00 - More infoProduct prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on [relevant Amazon Site(s), as applicable] at the time of purchase will apply to the purchase of this product.)

Ozone Venturi Injector for Cold Plunge, Ice Bath, Spa & Pool Pumps, 3/4" Barbed Inlet/Outlet, 1/4" Ozone Port, PVC Water Treatment & Fertilizer Injection for Irrigation

$27.99 (as of 17. March 2026 16:04 GMT +01:00 - More infoProduct prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on [relevant Amazon Site(s), as applicable] at the time of purchase will apply to the purchase of this product.)

UPLYKKE Irrigation Venturi Fertilizer Injector Kit - 1 inch NPT Threaded Interface Venturi Mixer Injector for Automatic Drip Irrigation System Agriculture Garden Water

$19.99 (as of 17. March 2026 16:04 GMT +01:00 - More infoProduct prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on [relevant Amazon Site(s), as applicable] at the time of purchase will apply to the purchase of this product.)

ApplianPar 3/4 Inch Garden Irrigation Device Venturi Fertilizer Kit Mixer Injector Switch Dispenser Water Tube Set

$15.05 $13.20 (as of 17. March 2026 16:04 GMT +01:00 - More infoProduct prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on [relevant Amazon Site(s), as applicable] at the time of purchase will apply to the purchase of this product.)

LQ Industrial 3/4Inch Black Irrigation Venturi Fertilizer Injector Agriculture Irrigation Device Tool

$8.99 (as of 17. March 2026 16:04 GMT +01:00 - More infoProduct prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on [relevant Amazon Site(s), as applicable] at the time of purchase will apply to the purchase of this product.)

Practical Test of the Irritec 3/4-Inch Injector

To give you a concrete example of an application and a starting point for your own further considerations, I tested the Irritec 3/4-inch injector in practice. I tested it with a fairly powerful Grundfos Scala 1 5-55 pump, which still has reserves for its current irrigation task. A pressure of approximately 60 psi is required in the area to be irrigated (40 psi sprinkler, 10 psi pipeline, 10 psi elevation difference when drawing water from the well). The hourly water flow in the tested zone for irrigation without fertilization has so far been approximately 700 gallons.

I screwed the nozzle and intake hose together to form the injector as they came, without any additional sealing material, and installed the injector directly into the pipeline, without a bypass. The intake hose simply hung from there into a standard bucket filled with fertilizer. A very simple design, but perfectly adequate for the test purpose. For permanent use, it could and should certainly be made even more stable and visually appealing.

My simple installation, limited to the essential function, for test purposes

And then an irrigation run was started immediately. Result: The fertilizer intake in the Venturi injector worked perfectly and powerfully, but the sprinklers no longer had the necessary pressure to extend properly and only irrigated at half-mast with significantly reduced throw distances.

Interim conclusion: As expected from the manufacturer’s performance tables (see earlier in the article), the Venturi nozzle limited the maximum possible water flow due to the constriction in the nozzle. This would not be practical in this configuration, as the fertilizer would be distributed very unevenly due to the completely inadequate throw distances.

I then tested the same setup in a second zone, which has a significantly lower water flow of 450 gallons per hour. With this zone, irrigation worked perfectly as usual, with the usual spray distances. And the fertilizer intake also continued to work flawlessly.

Test with installed bypass

I conducted my next test again on the large 700-gallon zone. I quickly built a bypass branch using connectors, pipe sections, and a valve. The bypass branches off downward from the main line, then runs through the Venturi nozzle, and returns to the main line. Parallel to this, the main line continues directly, with an additional valve installed after the branch to the Venturi nozzle to regulate the pressure.

Venturi nozzle integrated into a bypass

In my first test run with the bypass solution, I left the valve fully open so that the water could flow through unhindered. As expected, the irrigation system received sufficient water and functioned as normal. However, the Venturi nozzle did not suck in any fertilizer in this way, as the nozzle constriction was not sufficient in this configuration to generate the required pressure difference.

I then gradually closed the valve until the intake hose began to draw in fertilizer. This was easy to control, and at the lowest possible dosage, where the fertilizer was only sucked out of the bucket very slowly, the irrigation felt almost normal, with only a very slightly reduced throw distance. But even at a higher dosage, it continued to function quite well, with throw distances that were still usable in practice.

Interim conclusion: With a bypass branch, you can easily get closer to the desired result and find a suitable balance between fertilizer dosage and pressure loss.

Test conclusion

The Venturi injector met my expectations: Setup is straightforward and inexpensive, and you can quickly achieve a usable result. Since it allows for significantly more flexible and precise adjustment, I would definitely prefer the bypass installation to the in-line installation for long-term use. The additional installation time only takes a few minutes, or if that’s too tedious for you, you can also purchase ready-made bypass solutions.

Note: After fertilization is complete, you should continue to water with clean water for about half an hour to ensure that all fertilizer residues are washed out of the system and that no algae or microorganisms can form.

Der Beitrag How to fertilize with a Venturi injector erschien zuerst auf Irrigation Blog for Do-it-yourselfer.

First of all: The Netspex Sprinkler System Designer does not plan a complete irrigation system like the other three tools, i.e. it does not make a complete proposal from sprinklers to pipelines to irrigation computers, but rather focuses entirely on the topic of sprinklers. This includes selecting the right sprinkler and the optimal, water-saving placement of the sprinkler on the agricultural area.

The tool is free; to use it, you need to register once, which, according to the information on the website, is processed within a maximum of 48 hours. In my test, it only took about 10 minutes and I received the access data by email. This gives you full access to the planning tool; beforehand you can optionally try out the functionality in a (functionally limited) demo version.

When you start the planning tool, you can select the desired language and the desired unit of measurement system.

You can start planning in two different ways:

• By selecting the sprinkler
• By selecting the desired application

Selection of the starting point

If you select “Select a sprinkler”, you skip the selection of the desired application. This is recommended if you already have a specific idea of ​​the sprinkler you need. If you don’t have one, then it seems better to start with the menu item “Select an application”. Here the planner first asks you what application you are planning and this then limits the selection of sprinklers available in the next step to those that are suitable for that purpose.

However, in my test of the tool, it turned out that the further systematic planning when selecting this menu item is probably not suitable for most users, see my comment below. Therefore, it makes the most sense to use the menu item “Select a sprinkler” or perhaps a mix of both methods: So first – if you are still unsure – use the menu item “Select an application” to find out which sprinklers are suitable for the intended application, but then start again from the beginning with the menu item “Select a sprinkler”, as this enables better further planning. I will then present both methods so that it becomes clear what the differences are:

Planning with starting point selection of a sprinkler

Here you can first select the desired sprinkler family and within this the desired sprinkler model from the entire range of Netafin impulse sprinklers and micro irrigation sprayers. The range of water flow and working pressure for each sprinkler family is given. Unfortunately, this data is not given in detail for the models available for selection within the family, but it is usually clear from the model name.

Selecting a Sprinkler Family

And then select the specific sprinkler model

If you are still unsure about which sprinkler model to choose, it is better to first take a detour to the “Compare” menu item, where you can select several sprinklers and compare their performance data.

Placement of the sprinklers

Based on the selected sprinkler model, the specific positioning of the sprinklers on the area to be irrigated is now planned. To do this, you first need to determine the pattern in which the sprinklers should be placed. The two most commonly used systems are the rectangular pattern, in which 4 sprinklers are placed so that they enclose a square area, and the triangular pattern, in which three sprinklers form a triangle. There are also four other systems to choose from.

The next step is to make the basic decision as to whether the sprinklers should be placed on the ground or hanging from above. Then you have to specify how high above the ground the sprinkler should be and what flow rate and working pressure it should work with. Since I have already selected a specific sprinkler model that can only be used standing on the ground, in my case only this selection is possible from the start and only one selection is possible for the height, flow rate and working pressure. In this sense, it is a bit misleading that you still have to make a selection here (limited to one option), the system could actually predefine this.

Now you still have to define how far apart the sprinklers should be from each other. The distance between the sprinklers in a pipeline string is specified under “distance between heads”, and the distance from one pipeline string to the next is specified under “distance between laterals”. So basically the horizontal and vertical distances between the sprinklers. In the classic square formation, these distances would be the same and when planning lawn irrigation with circular sprinklers, you would plan with double overlap.

When using impulse sprinklers, which also irrigate much better in the immediate vicinity of the sprinkler, such a strong overlap is not mandatory. With the planner, you can easily find the optimal pattern for the intended purpose, which provides sufficient uniformity of irrigation while using sprinklers and water as economically as possible. The distances can be adjusted using sliders and the resulting pattern is immediately displayed in a preview image.

Planning the sprinkler spacing

And after clicking on the “Show Performances” button, you can then see what performance data this planning would lead to.

Performance indicators

Sprinkler Performance Data

On the one hand, the precipitation rate that would result from the planning is given here. And on the other hand, three performance indicators for the uniformity of irrigation are given:

• Christiansen Coefficient of Uniformity (CU): The least strict of the three methods.
• Distribution Uniformity (DU): Stricter than the previous method
• Scheduling Coefficient (SC): The strictest of the three methods

For all three indicators, the higher the value, the more uniform the irrigation. The values ​​of the first two indicators can be between 0 and 100%, with 100% meaning completely uniform irrigation, i.e. that every spot on the area to be irrigated receives exactly the same amount of water. For the Scheduling Coefficient (SC), a value as close to 1 as possible is ideal. This indicator is a runtime multiplier that indicates the factor by which the irrigation runtime would have to be increased to ensure that even dry areas are sufficiently irrigated.

In addition, the uniformity of the irrigation is shown in a precipitation diagram, with the different shades of blue showing how evenly or unevenly the irrigation is. By changing the sprinkler distances, you can test how the individual key figures change and thus get even closer to the optimal placement of the sprinklers.

At the very bottom, another diagram shows how evenly the selected sprinkler distributes the water over its throw distance, i.e. how much water is distributed in the immediate vicinity of the sprinkler, how much is distributed after one foot, two feets, etc. etc. This information is very interesting, but would ideally have been displayed one step earlier in the sprinkler selection point, so that the original sprinkler selection could have already been based on it.

The key figures determined, including key data, can be output as a printable PDF by clicking on “Create PDF”.

Planning with starting point selection of the desired application

I will now describe the second option for using the online planner. Here you do not start with the sprinkler selection, but first determine the intended use.

Determining the intended use

You can choose between:

• Field crops and vegetables
• Orchards
• Protected crops
• Frost mitigation

Specification of the intended use

In the menu items “Orchards” and “Protected crops” a further sub-selection can be made: In orchards you can choose between irrigation, frost protection, cooling and cleaning and in protected crops you can choose between full irrigation, bay irrigation, germination, rooting, humidification and cooling.

Placement of the sprinklers

Once you have selected the desired application, you must specify how you want to position the sprinklers. This information is identical to that of the previously presented method: selection of placement on the ground or from above, determination of the distance between the sprinklers, precipitation rate, desired working pressure and height of the sprinklers. The only irrigation patterns available here are rectangular pattern and triangular pattern.

Sprinkler placement menu

My impression: This system seems a bit poorly thought out or strangely solved to me. Usually you determine these things based on the sprinkler you want to use, because it has to be able to meet the requirements. Doing it in the reverse order, i.e. first theoretically considering the sprinkler spacing, rainfall rate and water pressure and then looking for the sprinkler based on that, is on the one hand a rather difficult task and could also limit you completely unnecessarily because certain sprinklers that would have been considered might then not meet the requirements at all.

In my opinion, this approach would only really make sense if you already had a finished irrigation system with pipelines, specified sprinkler spacing, etc. in operation and wanted to replace the sprinklers with a new model. I would therefore recommend using the method presented in the previous step with the starting point “placement of the sprinklers”, which does not have this significant disadvantage. This method is only suitable, if at all, to get a basic idea of ​​what type of sprinklers Netafim offers based on the intended application.

Sprinkler selection

Based on the information you provided previously, you will now be shown the Netafin sprinklers that meet these requirements and you can select the sprinkler you want.

Selecting the sprinkler from a selection based on the previously made entries

Performance metrics

This display is identical to the one described above at the starting point “Select a sprinkler” and shows the uniformity of the irrigation using three metrics and a precipitation graph, as well as the precipitation rate and the water distribution over the throw of the sprinkler. By changing the distance between the sprinklers, you can test the effect of different distances.

Display of performance indicators

Conclusion and recommendation

The strength of the Netspex sprinkler system designer lies primarily in the assistance it provides with the optimal placement of the sprinklers. You can easily try out different distances between the sprinklers with different sprinklers and observe how the uniformity of the irrigation develops as a result, or make conscious changes in order to approach a desired target of uniformity and precipitation rate. This is a good help with sprinkler positioning and is useful for checking previous considerations.

The disadvantage is that the sprinkler selection is limited to the Netafim product range. Using the planning tool makes sense especially if you want to use Netafim sprinklers or at least sprinklers that have very similar performance data. If you use other sprinklers, these can differ significantly in terms of throw distance and water distribution, so that the values ​​in terms of uniformity of irrigation and precipitation rate would be completely different.

Another small drawback is that the order in which steps are carried out in the sprinkler system designer does not seem to be 100% well thought out in some situations, so that you sometimes have to make decisions that are difficult to make at this point. However, the problem can be circumvented with workarounds, so I don’t rate this deficit too highly. A little fine-tuning would do the program some good, though.

All in all, a very interesting online service that focuses primarily on testing sprinklers and their optimal positioning for the most economical use of water and therefore seems well suited to agricultural purposes.

Further link

Below is the link to the Netspex online planning tool:

Netafim Netspex Sprinkler Designer

As an alternative to the browser version, the Netspex Designer is also available as an app for Apple and Google.

Der Beitrag Introducing Netafim Netspex: Free sprinkler planning tool for agriculture erschien zuerst auf Irrigation Blog for Do-it-yourselfer.