Patented hybrid technology
A counter-current swim machine creates a current in the water that you swim against, so you stay in one place. This lets you swim continuously and freely, even in a smaller pool.
EVAstream combines an in-house developed propeller, with three overlapping blades, with a streamlined turbine tunnel. The propeller moves a large volume of water and builds pressure at low speed. The streamlined turbine tunnel concentrates the flow and gradually accelerates the water towards the outlet. The result is a wide, powerful current that reaches far into the pool, giving you a spacious swim zone where you can swim freely.
The combination of the in-house developed propeller and the streamlined turbine tunnel is patented internationally.
How it works
The EVAstream is the result of more than three years of engineering. The patent lies in how two components work together: the in-house developed propeller and the streamlined turbine tunnel around it. Together, they turn a large volume of water into a fast, wide current.
Step 1
The in-house developed propeller, with three overlapping blades, moves a large volume of water and builds pressure at low speed. This keeps the EVAstream very quiet and low in vibration.
Step 2
The streamlined turbine tunnel converts that pressure into speed. The water accelerates gradually towards the outlet and stays wide.
Step 3
A wide current with strong thrust comes out of the outlet. That force carries the current far into the pool, beyond your swim zone.
This is how the EVAstream gets up to over 2.5 times as much thrust from the same volume of water as another swim machine with the same water displacement. You’ll feel the difference in the swim zone: a powerful current that reaches far into the pool.
The principle
The volume of water alone doesn’t determine how a counter-current feels. The flow speed, width and reach of the current matter too.
Water displacement (m³/h) tells you how much water a swim machine moves; flow speed (m/s) tells you how fast. What gives the current its power is the combination of the two: thrust. The EVAstream 275 sets the water in motion with a thrust of approx. 52 kg. At the same water displacement, that’s more than 2 times as much as another swim machine with the same water displacement. That force carries the water far into the pool and gives you a powerful, even counter-current.
How much water
275 m³/h
×
How fast
6.7 m/s
=
Thrust
approx. 52 kg*
*Simplified representation. The full calculation converts m³/h to m³/s and takes water density and gravity into account.
See for yourself
Choose a model and use the button to switch between the EVAstream and another swim machine with the same water displacement. See how far the current reaches in an 8 × 4 m pool.
|
EVAstreamWater displacement |
Thrust |
Other swim machine |
|---|---|---|
|
175 m³/h |
approx. 21 kg |
approx. 230 m³/h (1.3×) |
|
225 m³/h |
approx. 35 kg |
approx. 380 m³/h (1.7×) |
|
275 m³/h |
approx. 52 kg |
approx. 565 m³/h (2.1×) |
|
450 m³/h |
approx. 70 kg |
approx. 760 m³/h (1.7×) |
|
350 m³/h |
approx. 85 kg |
approx. 925 m³/h (2.6×) |
|
550 m³/h |
approx. 104 kg |
approx. 1,130 m³/h (2.1×) |
|
700 m³/h |
approx. 170 kg |
approx. 1,850 m³/h (2.6×) |
Sorted by thrust. The EVAstream 450 has two turbine units, each with the same outflow speed as the 225, so it has less thrust than the 350.
Compared with a typical swim machine
Other swim machines have an outflow speed of around 2.5 to 4 m/s. In the comparison, we use the midpoint: approx. 3.25 m/s. With the EVAstream 275, the same water flows out more than 2 times as fast: 6.7 m/s. That gives more than 2 times as much thrust; with the EVAstream 350 and 700, it’s more than 2.5 times. The current reaches further into the pool, carries more water with it and gives a noticeably higher swimming speed in the swim zone.
To achieve the same thrust, the other swim machine needs up to over 2.5 times as much water. The EVAstream 275 sets the water in motion with a thrust of approx. 52 kg, from 275 m³/h. The other swim machine needs approx. 565 m³/h to do the same. So water displacement alone says little: compare counter-current swim machines on thrust.
Wide and powerful
Where you swim, in the middle of the swim zone, the EVAstream’s current is approx. 1.5 metres wide. That’s well wider than your shoulders. From the outlet, the water gradually fans out. The streamlined turbine tunnel gives the water the thrust it needs to stay powerful to the end of the swim zone. And because the current starts out compact, the water has room to flow back along the side walls. This keeps the water in your pool circulating well.
The EVAstream is designed for the most commonly built private pools. It works best in a pool that’s about twice as long as it is wide, like the 8 × 4 m pool in the tool. At that ratio, the current has room to reach far and flow back along the walls. The EVAstream FlowLab shows you how the current will perform in your own pool.
Steplessly adjustable
The EVAstream’s high outflow speed isn’t the goal but the means. Together with the water displacement, it produces the thrust that keeps the current wide and carries it far into the pool.
What you feel isn’t the speed at the outlet. The current gradually fans out and slows down. In the middle of the swim zone, where you swim, it’s approx. 1.5 metres wide and the water flows at swimming speed. The current surrounds your body with even resistance.
The EVAstream is infinitely adjustable. When you turn it down, the shape of the current stays the same: just as wide, just as stable, only calmer. The streamlined turbine tunnel determines the shape; the setting determines only the speed. So at every setting you swim in a wide, stable current, from relaxed lap swimming to intensive training.
For the swimmer
The streamlined turbine tunnel concentrates and accelerates the current, so it reaches further into the pool. This gives you a natural swimming position, an extra-spacious swim zone and a focused current that fully surrounds your body.
You’re automatically brought into a stable, natural swimming position. The current is aimed at your upper body rather than your head, giving you plenty of room to breathe and no annoying splashing.
Because the current reaches further into the pool, you don’t have to swim close to the machine. Even further from the outlet, you’re still fully in the current, and that’s where it’s wider: approx. 1.5 metres in the middle of the swim zone, well wider than your shoulders. This gives you more room to speed up and slow down without touching the pool edge. On the EVAstream 450 and 550, two outlet units create an even wider swim zone.
De snelle kern van de stroming blijft lang gebundeld en is breed genoeg om uw lichaam volledig te omsluiten. Zo ontstaat een gelijkmatige tegendruk over het lichaam en maakt u optimaal gebruik van de tegenstroming.
The current lifts you up and gives you more room to swim.
The sound
A powerful swim current doesn’t have to make much noise. EVAstream is designed for low speed and minimal vibration, so the technology stays in the background as much as possible while you swim.
“Low-noise” means little without a number. That’s why we had the sound measured. EVAstream’s sound level was measured independently by a Swiss acoustics firm. At a water displacement of 215 m³/h, it measured 29 dB, comparable to leaves rustling in a gentle breeze. Another counter-current swim machine, measured under the same conditions, came in at 52 dB, comparable to a running washing machine.
The in-house developed propeller, with three overlapping blades, moves a large volume of water and builds pressure at low speed. Fewer revolutions mean less mechanical noise and less vibration. Precise balancing of the moving parts further reduces vibration.
So what you hear is mostly the water, not the technology behind it.
FOR EXISTING POOLS
We developed the EVAstream Move especially for existing pools. It’s a wireless, battery-powered swim machine that you place in the pool yourself. It uses the same patented hybrid technology as the built-in EVAstream, but it’s portable and needs no demolition work.
View the EVAstream Move
EVAstream FlowLab
Enter your pool’s dimensions and see, for each EVAstream model, how the swim zone works out. That way, you know what’s possible before you sit down with your pool builder. For the water displacement and flow speed of each model, see EVAstream models and specifications.
See the EVAStream in your pool All EVAstream models and specifications
TRIAL SWIM
Discover for yourself what the EVA System does for a pool. Feel the current, see the light in the water, and swim a workout in which the light guides you through the session.
Book a trial swimTHREE EXPERIENCES
In the EVA System, the EVAstream swim machine, underwater lighting and controls work together as one system in your pool. How do you want to use your pool?
Swim freely in your own pool, whenever you like. Even in the evening, thanks to the optional EVAsubaqua underwater lighting.
Frequently asked questions