Publications

Displaying 1 - 25 of 102

November 2022 NIST Premise Plumbing Research Workshop: Summary and Findings

July 28, 2023

Author(s)

Andrew K. Persily, Marylia Duarte Batista, William M. Healy, Mark A. Kedzierski, Lingnan Lin, Natascha S. Milesi-Ferretti, Tania Ullah, David A. Yashar, Stephen Zimmerman

Premise plumbing systems need to meet a range of performance goals including occupant health and comfort, energy and water efficiency, and reduced environmental impacts. Pressures to improve water efficiency and building water quality, combined with the

Measurement Science Research Needs for Premise Plumbing Systems

May 11, 2020

Author(s)

Andrew K. Persily, David A. Yashar, Natascha S. Milesi-Ferretti, Tania Ullah, William M. Healy

Premise plumbing systems provide key building services and exist in the context of a range of performance goals related to building energy efficiency, water conservation, reduced environmental impacts, and occupant health and comfort. Pressures to improve

EVAP-COND, Version 4.0; Simulation Models for Finned-Tube Heat Exchangers with Circuitry Optimization

June 28, 2016

Author(s)

Piotr A. Domanski, David A. Yashar, Janusz Wojtusiak

EVAP-COND is a software package that contains NIST's simulation models for a finned-tube evaporator and condenser. The tube-by-tube modeling scheme allows for specifying complex refrigerant circuits, modeling refrigerant distribution between these

Rooftop Air-Conditioning Unit Performance Improvement using Refrigerant Circuitry Optimization

March 20, 2015

Author(s)

David A. Yashar, Sunil Lee, Piotr A. Domanski

This study demonstrates the performance improvement of an air-to-air 7.5 Ton (26.4 kW) rooftop unit (RTU) achieved by optimizing an evaporators refrigerant circuitry using evolutionary algorithms. We measured its cooling capacity and Coefficient of

An Experimental and Computational Study of Approach Air Distribution for Slanted and A-Shaped Finned-Tube Heat Exchangers

January 25, 2015

Author(s)

David A. Yashar, Piotr A. Domanski, Hong Hyun Cho

An Experimental and Computational Study of Approach Air Distribution for Slanted and A-Shaped Finned-Tube Heat Exchangers

July 1, 2014

Author(s)

David A. Yashar, Piotr A. Domanski, Hong Hyun Cho

One of the most influential factors of the performance of a finned tube heat exchanger is the distribution of the air passing through it; therefore it must be known in order to produce a highly efficient design. We examined two different common style air

Beyond Standard Efficiency Ratings

May 6, 2014

Author(s)

David A. Yashar

Evaluation of Energy Consumption Rating Methods for Thermoelectric Wine Chillers and Compact Refrigerators

October 21, 2013

Author(s)

David A. Yashar, Young-Jin Baik

Most types of refrigerating appliances are rated according to an established test procedure and their energy use is regulated by the US Department of energy. These products are generally built around a vapor compression system that is used to maintain a

Improving the Performance of a Roof Top Air-Conditioning Unit by Refrigerant Circuitry Optimization

August 2, 2013

Author(s)

David A. Yashar, Sunil Lee

This study demonstrates the performance improvement of an air-to-air roof top unit (RTU) achieved by optimizing an evaporators refrigerant circuitry using evolutionary algorithms. The subject of this study is a unit with a cooling capacity of 7.5 Tons (26

Performance Improvement of a Roof Top Air-Conditioning Unit by Refrigerant Circuitry Optimization

January 26, 2013

Author(s)

Sunil Lee, David A. Yashar, Piotr A. Domanski

In this experiment-aided simulation study, we achieved the performance improvement of a Roof Top Unit (RTU) by optimizing an evaporator's refrigerant circuitry using evolutionary algorithms. The system used in this study was a 2-stage 7.5 Ton RTU with an

A Dual Mode Evolutionary Algorithm Approach for Designing Optimized Finned-Tube Heat Exchangers

September 27, 2012

Author(s)

David A. Yashar, Piotr A. Domanski, Janusz Wojusiak, Kenneth Kaufman

The efficiency of a vapor compression system is strongly influenced by the performance of the finned-tube heat exchangers it employs. Heat exchanger performance is strongly influenced by the refrigerant circuitry, i.e., the connection sequence of the tubes

Development of a Method to Measure the Energy Consumption of Automatic Icemakers in Domestic Refrigerators with Single Speed Compressors

September 18, 2012

Author(s)

David A. Yashar

This study examines the energy consumption of automatic ice makers installed in domestic refrigerators. This study builds upon the findings of a previous study and examines two refrigerator-freezers of different configurations, one French-door units with

Energy Consumption of Automatic Ice Makers Installed in Domestic Refrigerators, Revision 1

December 7, 2011

Author(s)

David A. Yashar, Ki-Jung Park

This study examines the energy consumption of automatic ice makers installed in domestic refrigerators. The purpose of this research is to determine a method of measuring the energy consumption of automatic ice makers that will generate a repeatable and

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