Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Additives may save energy for cooling big buildings

18.11.2005


NIST laboratory experiments have demonstrated that adding small amount of additives to refrigerants may significantly improve the efficiency of commercial air conditioning.


A National Institute of Standards and Technology (NIST) researcher has come up with a method designed to improve the energy efficiency of water chillers that cool the nation’s large commercial buildings. The NIST method, if confirmed through experiments with full-scale chiller systems, could save as much as 1 percent of the 320 billion kWh of electricity used annually by chillers or an equivalent 920,000 barrels of oil a day, according to Mark Kedzierski, the NIST mechanical engineer who developed the technique.

The advance builds on past NIST research designed to optimize mixtures of chiller refrigerants with lubricants. The researchers discovered that some lubricants, when injected in small amounts, can significantly enhance evaporator heat transfer, increasing the efficiency of chillers. When they studied the process more closely they found the most efficient heat transfer occurred when the added oil’s surface tension, viscosity, composition and chemical characteristics complemented those of the chiller’s base lubricant.

In a recent paper* describing the method, Kedzierski describes how the right additive forms a very thin covering on an evaporator surface, which produces enhanced bubbling during boiling. The improved conversion of the refrigerant molecules into vapor molecules increases the chiller’s cooling capacity similar to a heat pump.



Kedzierski developed rules for the selection of the different types of oil additives according to the type of chiller lubricant, making successful energy enhancement less of a hit-or-miss proposition. Laboratory work is under way testing the energy enhancing potential of several oil and lubricant combinations that have been identified by the rules.

"The leap from a successful laboratory experiment to an everyday large-scale cooling application is a big one. NIST wants to see this theory translated into products germane to manufacturers as soon as possible," Kedzierski said. "We welcome private-sector interest in the theory and its application."

*M. Kedzierski. Method and transport properties for enhancing the nucleative heat transfer of refrigerant chiller evaporators. PriorArt Database, ip.com. Online publication date, Sept. 28, 2005. The NIST theory and research is also described at http://www.bfrl.nist.gov/pdf/NISTIR7132.pdf.

John Blair | EurekAlert!
Further information:
http://www.bfrl.nist.gov/pdf/NISTIR7132.pdf

More articles from Power and Electrical Engineering:

nachricht Scientists create biodegradable, paper-based biobatteries
08.08.2018 | Binghamton University

nachricht Ricocheting radio waves monitor the tiniest movements in a room
07.08.2018 | Duke University

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: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

Im Focus: Lining up surprising behaviors of superconductor with one of the world's strongest magnets

Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur

What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...

Im Focus: World record: Fastest 3-D tomographic images at BESSY II

The quality of materials often depends on the manufacturing process. In casting and welding, for example, the rate at which melts solidify and the resulting microstructure of the alloy is important. With metallic foams as well, it depends on exactly how the foaming process takes place. To understand these processes fully requires fast sensing capability. The fastest 3D tomographic images to date have now been achieved at the BESSY II X-ray source operated by the Helmholtz-Zentrum Berlin.

Dr. Francisco Garcia-Moreno and his team have designed a turntable that rotates ultra-stably about its axis at a constant rotational speed. This really depends...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

2018 Work Research Conference

25.07.2018 | Event News

 
Latest News

'Building up' stretchable electronics to be as multipurpose as your smartphone

14.08.2018 | Information Technology

During HIV infection, antibody can block B cells from fighting pathogens

14.08.2018 | Life Sciences

First study on physical properties of giant cancer cells may inform new treatments

14.08.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>