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 Engineering Laboratory /Building Energy & Environment Division
      HVAC&R Equipment Performance Group
                      The HVAC&R Equipment Performance Group expands the scientific knowledge of air-conditioning, heat pumping, and refrigeration technology. The Group's focus is to improve the energy efficiency of HVAC&R equipment, which is the predominant end-user of energy in buildings. The research activities include innovative and fundamental heat transfer measurements of refrigerants; experimental and analytical studies of systems and components; development of

      
  The research activities encompass analytical and experimental studies of new-generation refrigerants; experimental and simulation investigations of space-conditioning systems in current and net-zero energy buildings; and research of novel cooling/refrigeration technologies.  The current projects include:

Characterization of the performance potential of novel refrigerants
	Development of test and predictive methods for characterization of flammability of mildly flammable single-component refrigerants and refrigerant blends
	Fundamental two-phase heat transfer measurements for new generation single-component refrigerants and refrigerant blends
	Development of automated fault detection and diagnostic methods for field-assembled air conditioners and heat pumps
	Development of computational intelligence-based tools for optimization of component and system designs
	System studies through laboratory measurements and computer simulationsThe best-known contributions of the Group are those related to the research of environmentally-acceptable refrigerants, the development of advanced simulation tools, and the formulation of the SEER and HSPF performance descriptors for the test procedures of residential air conditioners and heat pumps.

Staff Directory

    
  News and Updates
      
                          Spotlight: Overhauling the Refrigeration Industry to Fight Global Warming
                        June 26, 2022NIST researchers are tackling the question of alternative refrigerant fluids.

    

  
  

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  Projects and Programs
      
                          Fault Detection and Diagnostics for Air-Conditioners and Heat Pumps
                  OngoingFault detection and diagnostic (FDD) methods are receiving increasing consideration for application in space-conditioning equipment as a method to reduce energy
  Flammability Metrics for New Low-GWP Refrigerants
                  OngoingIn response to worldwide initiatives to phase down working fluids that have a high global warming potential if accidentally released, the refrigeration and air
  Low-GWP Refrigerants for High-Efficiency HVAC&R Equipment
                  OngoingThe refrigeration and air-conditioning industry is moving to limit or phase out several refrigerants currently used in commercial and residential cooling and
  Space-Conditioning Options for Energy-Efficient Buildings
                  OngoingSpace-conditioning equipment accounts for 32 % of electricity use in homes and 17 % in commercial buildings , annually costing $49 Billion and $21 Billion USD

    

  
  

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  Publications
      
                          Air Humidity Influence on Combustion of R1234yf (CF3CFCH2), R1234ze(E) (trans-CF3CHCHF) and R134a (CH2FCF3) Refrigerants
                        February 23, 2024
                  Author(s)
                                Gregory T.  Linteris,   Valeri I.  BabushokThe influence of air humidity on flame propagation in mixtures of hydrofluorocarbons (HFCs) with air was studied through numerical simulations and comparison
  Evaluation of Experimental Methods for Burning Velocity of Flammable Refrigerants
                        September 25, 2023
                  Author(s)
                                Gregory T.  Linteris
  Elucidating the challenges in extracting ultra-slow flame speeds in a closed vessel - A CH2F2 microgravity case study using optical and pressure-rise data
                        September 25, 2023
                  Author(s)
                                Raik  Hesse,   Chaimae  Bariki,   Michael  Hegetschweiler,   Gregory T.  Linteris,   Heinz  Pitsch,   Joachim  BeeckmannRefrigerants with a low global warming potential (GWP) possess mild flammability. Hence, a fundamental understanding of their combustion characteristics is
  Simultaneous Particle Image Velocimetry and Schlieren Measurements of Slow-burning Flames
                        September 25, 2023
                  Author(s)
                                Christian  Schwenzer,   Raik  Hesse,   Roman  Glaznev,   Valeri I.  Babushok,   Gregory T.  Linteris,   Heinz  Pitsch,   Joachim  BeeckmannThe measurement of laminar flame speed is an essential factor in determining the reactivity, exothermicity, and diffusivity of a combustible mixture. In this

    

  
  

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  Software
      
                          CYCLE_D-HX:  NIST Vapor Compression Cycle Model Accounting for Refrigerant Thermodynamic and Transport Properties  Version 2.0
                        January 10, 2021CYCLE_D-HX simulates the performance of single-compound refrigerants and refrigerant blends in subcritical vapor-compression refrigeration cycles. The basic
  CYCLE_D-HX: NIST Vapor Compression Cycle Model Accounting for Refrigerant Thermodynamic and Transport Properties
                        October 24, 2017CYCLE_D-HX simulates the performance of single-compound refrigerants and refrigerant blends in subcritical vapor-compression refrigeration cycles. The basic

    

  
  

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  Awards
      
                          2017 - Gold Medal Award---Andrei F. Kazakov, Mark O. McLinden, Piotr A. DomanskiFor identifying the best alternatives to hydrofluorocarbon chemicals essential to the future of the air-conditioning and refrigerating industries.
  Andrei Kazakov and Mark McLinden of MML Awarded 2017 DoC Gold MedalMark O. McLinden and Andrei F. Kazakov of MML, along with Piotr A. Domanski of EL, were awarded a 2017 Department of Commerce Gold Medal
  2016 - Jacob Rabinow Applied Research Award---Brian Dougherty, A. Hunter Fanney, William Healy, Lisa Ng, Joshua Kneifel, Farhad Omar, Dustin Poppendieck, Harrison Skye, Tania Ullah, W. Vance PayneFor development of a unique experimental testbed to support the building industry's delivery of energy-efficient, comfortable, and healthy homes.
  2016 - Bronze Medal Award---Piotr A. Domanski, W. Vance PayneFor conducting the first study of the impact of installation faults on heat pump performance, providing an authoritative basis for improved practice.

    

  
  

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EVAP-COND

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                Publications
  Contaminant Accumulation and Removal in Building Plumbing Systems
  
    Contacts
      
        

Gregory T. Linteris
    
      
  linteris@nist.gov
  (301) 975-2283
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