FRESH SOFTFLO
Improves the indoor climate • 2:01
Softflo technology
Effectively cools, heats and ventilates
industrial premises, offices and schools.
Jets and a soft flow improve the indoor climate
New findings within hydromechanics - confluent jets ventilation - open up the path towards
a completely different and improved indoor climate. The Softflo technology has been
developed from these findings.
A Softflo diffuser forms the supply air into many silent jets. These are directly converted to
a draught-free, “soft flow”, which seeks out sources of heat in the room via walls and floor.
As the jets allow the supply air into take control of the room air, it is possible to design
diffusers so that the soft flow stratifies (layers) the room air.
• Stratification occurs irrespective of whether the supply air diffuser
is placed in the ceiling, corner of the wall-ceiling, in the wall or at floor level.
• Stratification increase the efficiency of the ventilation
(removes contamination from the room) to between
69 and 80 per cent. (The efficiency of the
generally used mixing ventilation is
normally between 30 and 40 per cent.)
• Even the heat exchange between the room air and the supply air
increases to the same extent. Consequently, less
energy is used to cool or heat the room;
• and the entire room volume does not need to be cooled or heated.
Ongoing research indicates operating costs for cooling
and ventilation drop by 20 to 40 per cent.
• The supply air can be chilled to + 5ºC without comfort problems!
In addition, it can also be warmed to the same degree.
• Installation can be considerably simplified.
FRESH SOFTFLO
Improves the indoor climate • 2:02
Twice as effective supply air
Twice as effective heat exchange
Twice as fresh indoor air
Presentation of a new indoor climate
technology
Today researchers know that infrasound from
fans - a low frequency sound that we humans
cannot perceive - is a significant cause of
tiredness in our schools and at workplaces.
We now also know how we can easily solve
this environment problem, which has been
unknown to the general public.
Researchers also know how we should go
about doubling the efficiency of the supply air
in rooms, at the same time as we lower the
particle content in the air that we breathe by
more than 50 percent. Furthermore, in the
same way we can reduce the energy requirement for cooling, heating and ventilation by at
least 28 percent.
The stearin candle is
the symbol for the
Softflo technology.
The exchange of heat and air
between heat sources and the
room air becomes optimal if tinkering technicians do not interfere with blown air.
The researcher’s results are indisputable:
With the knowledge we possess today we can,
with simple means, improve the climate in our
work rooms compared to today’s standard.
And at a significantly lower cost.
In order to attain an improved climate, the
findings show that we must use completely different methods to introduce ventilation air into
the rooms than those currently employed.
The findings of the researchers were the inspiration behind the project Softflo CJV project
(= to ventilate through confluent jets and the
optimal management of these). Within this
framework designs are now being developed
that introduce air into the rooms in this way,
so that in the future we can all have a better
climate in our work rooms.
In order to hold the development work on the
right course we have allowed this to be governed by seven principles, to reach the set
objective - twice as good climate in the rooms
where we work.
FRESH SOFTFLO
Improves the indoor climate • 2:03
Principle 1
Air supplied to a room should be directed so
that it can never disturb the upward, warm
convection air around the different heat
sources in the room.
Remember the stearin
candle!
The convection air should therefore be
replaced with air which is supplied from below.
The Softflo products are designed to provide
such functionality.
Principle 2
Allow the supply air - if possible - to interact
with the thermal currents that form in the
room with heat sources.
This increases the efficiency of the ventilation,
while the particle content in the occupied zone
decreases.
Work together with
the laws of nature!
Principle 3
Air from a supply air diffuser should never be
directed towards air from another supply air
diffuser. This reduces the risk of draught.
Consequently, Softflo products are designed to
only distribute the supply air in one direction.
Avoid - if this is practically possible - the method currently
used to feed supply air into a room - recessed, two-way
supply air beams.
FRESH SOFTFLO
Improves the indoor climate • 2:04
Principle 4
Supply air diffusers should disturb the used air
at ceiling level as little as possible. This then
reduces the particle content in the occupied
zone.
If Softflo products are installed in the ceiling
they should be positioned as close as possible
to walls and with the supply air directed
towards these.
The Softflo technology turns ingrained
concepts upside down. However, those who dare to
believe in the laws of nature are the winners - just like
the people in the room.
Principle 5
The Softflo products are designed so that the
infrasound from fans is dampened using a
reactive technique instead of through sound
absorption material.
The infrasound is then reduced by more than
30 dB, 10 to 20 dB more than what is normal
when using traditional supply air diffusers.
Openings for flowing air can be designed so
that sound generation is minimised and the dampening
of low-frequency sound is optimised.
Principle 6
The Softflo products are designed so that
the overall pressure drop across the diffuser
is, to more than 90 percent, made up of the
pressure drop that forms when the supply air
flow passes the correctly designed openings,
from a flow standpoint, in the product.
The development project confirms that is it
possible to reduce the sound level from the diffuser by more than 10 dBA.
The low sound level makes it possible to place
a higher pressure drop across the Softflo
products. These can now work as silent
governing devices in the system, which
simplifies installations.
You can win a great deal if you allow the Softflo
products to be the governing devices in the system:
Dampers and duct silencers can be omitted. The air
flow can be preset.
FRESH SOFTFLO
Improves the indoor climate • 2:05
Principle 7
Consider the Softflo technology when
positioning the Softflo products.
New findings within hydromechanics open up
the path towards a completely new supply air
principle, which
safeguards and enhances the advantages
found in mixing and displacement supply air,
but eliminates their disadvantages. The Softflo technology has been developed from these
new findings - impinging jet ventilation and
confluent jets ventilation.
In the Softflo technology the supply air is
formed into silent jets, which are directly converted to a draught free “soft flow”.
As jets, the supply air takes control over the
room air’s behaviour and the development of
the soft flow in the room via the walls and floor
up until the heat sources. This results in the
stratification of the room air.
• Stratification occurs irrespective of
whether the supply air diffuser is positioned
in the ceiling, corner of the wall-ceiling,
wall or at floor level.
• Stratification increase the efficiency of
the supply air to between 67 and 80
percent, that’s to say, doubled compared
to mixing ventilation.
• Stratification also increases the heat
exchange between the room air and the
supply air. Furthermore, the room’s
complete volume does not need to be
chilled or heated.
• The supply air can be chilled by 20 K
without comfort problems! In addition,
it can also be heated to the same degree.
• Installation can be considerably simplified.
We use three tools to
optimise the Softflo technology:
1 Studies of research in Displacement
Ventilation/ Supply air through low
impulse devices.
2 Trials in test rooms.
3 Visualisation of tests and outcome using
CFD (Computational Fluid Dynamic).
NOTE: CFD is not computer software. Nevertheless, you
need a powerful computer to be able to handle the millions of differential equations necessary for a study.
FRESH SOFTFLO
Improves the indoor climate • 2:06
Experiences from the development
of the Softflo products are many
and interesting:
Confluent, treated jets
The cleanest room air and the most effective
supply air are obtained if products with jets
are placed on or close to a wall. The confluent
jets should then be directed at a specific angle
towards the wall or towards a surface, which
is a part of the diffuser’s design.
The supply air will now spread along
the wall in a suitable direction at a low and
controlled velocity. This process always results
in a draught free, occupied zone.
The effect of the Softflo technology
on the room air
A Softflo product that is placed on or
close to a wall and which takes control of the
all the air in the room through the numerous
jets, can now, more or less, stratify the air in
the room.
The particle content in the air, which we
breathe in the occupied zone, drops
dramatically - frequently by half or more.
As the jets take control of all the room air,
stratification becomes more distinct than
that accomplished with low impulse, supply
air diffusers.
The effect of the Softflo technology on
the efficiency of the supply air
In this Softflo product the jets are processed inside the
diffuser to eliminate draughts. Air exchange efficiency
increases from 30 - 40% - which is standard for traditional
wall diffusers - to between 69 and 80 %.
If a Softflo product is placed at floor level,
air exchange efficiency can, in many cases,
be accelerated to over 80 %. If however,
it is positioned at ceiling level you can expect
air exchange efficiency of about 80 %.
Accordingly, a Softflo product ventilates a
room twice as efficiently as traditional mixing
supply air diffusers or supply air beams.
In the same way, the heat exchange between
the heat sources and the supply air increases
when the room is cooled based on the Softflo
technology. Furthermore, you do not need to
cool the entire volume of the room.
Softflo technology for chilled
or heated supply air
As a result of the extremely large mixture of
indoor air to jets it is always possible to chill
the supply air down to +5 ºC and heat it to
+35 ºC without comfort problems.
FRESH SOFTFLO
Improves the indoor climate • 2:07
Chilled and heated air to rooms with
displacement or mixing ventilation
Over 100 years ago we were using different
models with displacement or layering ventilation, primarily in the process industry. When
this supply air method was introduced a few
decades ago as the “perfect method of introducing air to all types of rooms”, it roused
great hope. Many were convinced that we
were on the right path towards significantly
improved ventilation.
However, in time all expectations become
dashed. Problems with comfort and draught
arose when the supply air was only chilled to
three or four degrees and the use of heated
supply air in the diffusers was not possible.
Perhaps this fact is one of the reasons why
this supply air method did not live up to expectations and today is not an interesting option
for cooling rooms with comfort demands that
have surplus heat.
Only the occupied zone needs to be cooled.
Instead we had to look again to the ever
present mixing ventilation which, not least
through it frequently being integrated in chilled
beams, now dominates the market.
However, mixing ventilation has many significant disadvantages, of which several have
been highlighted in the introduction to this
presentation of Softflo technology. Besides,
what is annoying is that these deficiencies are
impossible to resolve within the laws of physics. If we wish to cool our work rooms in the
best possible way, bearing in mind the wellbeing of those using the rooms, then we must
avoid mixing ventilation.
In rooms with high ceilings the benefits are even greater.
The mechanical cooling can take a longer holiday if
the room air is layered. Source: Rehva Displacement
Ventilation Guidebook.
FRESH SOFTFLO
Improves the indoor climate • 2003-10-01 • 2:08
Chilled and heated air
to the room with Softflo
Studies in laboratories and comparisons with CFD
show that the Softflo technology always reduces the
energy requirement when cooling different rooms
compared with a mixing function. This reduction in
some cases amounts to 50 percent.
The three pictures on the previous page are taken
from the Rehva Displacement Ventilation Guidebook.
These illustrate the economic benefits attained with
the displacement function - if it was now possible,
as in the example on the previous page, to cool the
supply air 6 degrees with a low impulse diffuser,
which it is not in a room with comfort demands. On the other hand, it is fully possible
to cool the supply air even more using the
Softflo technology.
Summary
The results obtained from
development project confirm
the findings of the researchers
that the room air we now accept
at our work places can be significantly improved.
In addition, we now know that we use far
too much energy when we heat and cool
our work rooms using traditional supply
air diffusers and chilled beams.
During the course of the project we have
also received, through the implemented systems,
confirmation that the Softflo technology truly
simplifies the installations. More often than not, this
can translate into savings of several million Swedish
kronor for just one system. Property owners that
dare to trust the laws of nature and new technology
have a great deal to win here, and that’s not to
mention the profits when the rooms are conditioned.
FRESH AB
Box 7
SE-360 32 GEMLA
SWEDEN
Tel
0470-70 77 00
Fax
0470-70 77 39
E-mail [email protected]
www.fresh.se
Softflo-technology and Softflo-products are patent pending.
Copyright: (c) FRESH AB 2003 - Subject to alteration - Edition 0310