Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Ecotechnologies – Humidification applied to refrigeration equipment

06.11.2008
Humidifiers using fine droplets of water have invaded hypermarket fruit and vegetable display units and Parisian café terraces during heat waves. Today, the humidification technique has been extended to refrigeration installation air condensers to improve their energy efficiency. The key results: energy savings and fewer greenhouse gas emissions.

Did you know that more than 15% of the electrical energy produced in industrialized countries was consumed by cold production (12%) and air conditioning (3%)? Yet consuming kilowatts is increasingly expensive, reduces fossil fuel resources, and increases greenhouse gas emissions.

In the majority of refrigeration installations, the operating condition of the air condenser, located at the back of the unit, in contact with ambient air, is a decisive element in the amount of power consumed by the refrigeration unit.

Cemagref research is being conducted to improve the energy efficiency of the condensers of cooling devices using humidification techniques. The objective is to develop an efficient and economical process that can be adapted to mid- and high-power refrigerating devices, as low as 10 kWh.

The humidification principle

We have all experienced a sensation of heat when passing behind a functioning refrigerator or air conditioner. The cause of this phenomenon is the air condenser, a heat exchanger made up of tubes with air fins attached to the back of the device. This is where the cooling fluid condenses by releasing its heat into the ambient air. To limit the system’s energy consumption, humidification processes were born. The principle consists of saturating the ambient air in contact with the exchanger by projecting fine water droplets. Humidification of the air intensifies the heat exchange on the air side and reduces the cooling fluid’s condensation temperature. This lowers the compression rate in the cooling cycle and improves the compressor’s consumption of electrical power.

- Making gains at every level

The process empirically applied needed to be optimized in view of its application to air conditioning and industrial refrigeration. Research was initiated in this context in 2006 by the ENERFRI team at Antony. A preliminary mathematical model made it possible to estimate the energy savings that could be made with an optimized humidification process, reaching up to 20% of the total electrical energy consumed. In addition, by integrating the humidification system at the design stage, it was possible to reduce the loads of cooling fluid by 10%. Knowing that most of these fluids are suspected of contributing directly to the greenhouse gas effect, the direct gain for the environment is substantial.

- Improving scientific knowledge

A pilot project is being constructed to understand the interaction between the humidity and a surface made up of tubes and air fins spaced 2–3 mm apart. The theoretical models will then be validated by varying the size and number of droplets measured by an optical granulometer. What is the optimal water flow to prevent the condensers from producing drops that flow on the air fins and obtain a maximum effect for a minimal water consumption? What is the optimal droplet size? How far from the unit should the humidifier be installed? These are the questions that Cemagref researchers are attempting to answer so as to define the optimal conditions for efficient and economical humidification of air condensers.

Marie Signoret | alfa
Further information:
http://www.cemagref.fr
http://www.cemagref.fr/Informations/Presse/InfMediaEV/infomedia86EV/im86_rech1_EV.htm

More articles from Power and Electrical Engineering:

nachricht Factory networks energy, buildings and production
12.07.2018 | FIZ Karlsruhe – Leibniz-Institut für Informationsinfrastruktur GmbH

nachricht Manipulating single atoms with an electron beam
10.07.2018 | University of Vienna

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Research finds new molecular structures in boron-based nanoclusters

13.07.2018 | Materials Sciences

Algae Have Land Genes

13.07.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>