Technical Information

VorteXtract™ improves the Heat Transfer Coefficient of a heating system by removing Nitrogen gas, and prevents corrosion by removing dissolved Oxygen to an inert level, meaning that no corrosion can take place because one of the reactive elements has been removed.

By removing these two gases, Energy efficiency is improved dramatically (we’ve seen as high as 37% improvement but most people see around 18%), carbon emissions are cut by typically 23%. Maintenance costs are reduced because any air related issues no longer occur, and the overall lifespan of the system is increased by around six to seven years.

So what is the actual effect of Nitrogen gas within a wet heating system, and why is the positive effect of VorteXtract™ so dramatic?

Let’s look at the science:

Entrained air is produced naturally when the heating system is in operation. This is shown by Henry’s Law which enables us to accurately calculate the amount of dissolved gas within a working fluid (in this case water) at a given temperature and pressure.

In commercial systems, this volume of gas can be highly significant, especially when we consider that a microbubble will be between 10µ and 250µ in diameter and that these bubbles line the interior surface of radiators and pipes. The insulating effect of these bubbles must be overcome before heat energy can be conducted into an environment.

If we consider the average size of a microbubble to be 100µ, then for every 10 Litres of water in the system, we see the following effect:

The microbubbles (0.1 mm thick) lining the internal radiator surface act as an insulating barrier, slowing the rate of transfer of heat from the water to the radiator surface, which is what you feel or radiates into the room.

This affects the rate and efficiency of heat transfer to the radiator surface.

We can estimate additional thermal resistance from the air layer:

Thermal Resistance of Air Layer:

Air’s thermal conductivity ≈ 0.026 W/m·K
Diameter = 0.1 mm = 0.0001 m

This resistance will reduce the heat flux to the radiator surface, so more time and energy loss occurs due to inefficiency. But this energy doesn’t go into raising the radiator surface temperature – it just slows down the transfer, unless you maintain extra energy input to compensate for loss.

Let’s apply this to a real world model and determine the effects of this insulating layer. This is what is really happening inside your heating system, and how much energy is being wasted as a result.

Let’s say we have a radiator containing 10 L of water, and the inner surface is lined with microbubbles of air (~0.1 mm thick). These microbubbles act as a thermal barrier between the hot water and the metal surface of the radiator, reducing heat transfer.

We’ll model heat transfer from the hot water → through the air layer → to the radiator surface using Fourier’s Law and the thermal resistance network approach.

Thermal Resistance Components

In a simplified 1D steady-state conduction model, the total heat transfer is governed by:

Where:

• ΔT = temperature difference (e.g. 35°C)
• R_total = sum of all thermal resistances between water and surface
• Q = heat flow in watts (W)

Let’s focus on the added resistance from the air microbubble layer.

The Resistance of the Air Layer:

Where:

• d = thickness of air layer = 0.0001 m (0.1 mm)
• k = thermal conductivity of air ≈ 0.026 W/m·K
• A = internal surface area of radiator (m²)

Let’s assume a typical radiator has around 1.5 m² of internal surface area (varies by size and design).

Then:

Compared without an air layer present we would see water in direct contact with the radiator wall, and the thermal resistance of this would then dominate as air resistance would be negligible.  So let’s calculate how much heat is transferred both with and without the air layer present using a 35C temperature difference:

With the air layer:

Without the air layer:

This shows that the air microbubble layer reduces heat transfer rate by a factor of around 25x, dramatically insulating the radiator surface.

This is only one of the calculations we carry out to determine the potential energy reduction that we can achieve by installing VorteXtract™. In reality there is sufficient air in a given heating system to reduce thermal transfer by between 15% and 20% .. this of course doesn’t account for the benefits of removing dissolved Oxygen as well.

VorteXtract™ is able to remove these unwanted gases by creating a pressure differential within the chamber that encourages the remaining dissolved gases to gather and escape through the low pressure zone at the centre of the device. VorteXtract™ has been proven to reduce dissolved gas levels (Nitrogen, Oxygen and Carbon Dioxide) to below 0.00001% rendering them inert, and optimising the efficiency and thermal transfer capability of any wet heating system.