ASHRAE Journal - October 2013 - 71

research report

Expansion and Updating of the ADPI for Overhead Mixing Systems in
Both Cooling and Heating

The research could also have far reaching implications in terms of getting changes made
to the ASHRAE Handbook, to manufacturers’ literature and to the way engineers calculate
minimum flow rates. It will also support proposed changes in Standards 90.1, 62.1 and 55.

1546-RP

1517-RP Validation of a Low-Order Acoustic Model of Boilers and Its Application
for Diagnosing Combustion Driven Oscillations

The current ADPI table presented in the ASHRAE Handbook Fundaments Chapter 20
(table 3) and in the ASHRAE Applications Chapter 56 (table 4) is outdated and requires to
be revised. Also, obtaining ADPI values for overhead mixed air distribution systems may,
in some cases, justify reduction of the number of diffusers required to be supplied into
a space under peak cooling or heating load conditions without compromising thermal
comfort. This, in turn, will reduce required capacity, energy consumption of cooling and
heating systems and further reduce greenhouse gas emissions. The database of the ADPI
Selection Guide will be expanded for use in design practice. Submittals to USGBC LEED
for gaining the Thermal Comfort point (claiming compliance to ASHRAE Standard 55)
currently have difficulty using the existing ADPI table due to the unrealistic loads listed,
the unclear description of diffuser types, and the lack of heating parameters necessary to
claim a design will comply with the vertical stratification requirements of that standard.
Updating the table to make it more applicable to low cooling loads and overhead heating
situations will allow better input to those seeking to show compliance to Standard 55 and
the associated LEED point.

September 2010 – September 2013; Secat, Inc.; Principal Investigator, David Herrin; TC 6.10, Fuels and Combustion

During the development of higher efficiency, lower emission boilers, tonal noise can
be an unacceptable problem. This is caused by oscillations of the flame which result in
pressure oscillations in the combustion chamber that are radiated as noise. This occurs
whenever the pressure oscillations feedback on the flame, via the mixture supply system, in such a manner that the flame oscillations increase. The interaction of the boiler,
burner, and flame is so complex that breaking the circle is best accomplished with the
help of a computer model.
The objective of this research is to develop a procedure for quickly and efficiently
modeling the acoustic behavior of gas fired heating boilers as a tool for diagnosing the
cause of combustion oscillations.
ASHRAE members who would benefit immediately from the proposed research are
engineers engaged in the development of high efficiency, low NOx gas fired boilers for
residential and small commercial applications. It is expected that the results will also
benefit engineers involved in the development of gas fired furnaces and liquid fueled
boilers as the demand for lower NOx emissions from those products spreads in the near
future. Together, gas and oil burning boilers and furnaces are used to heat the vast majority of homes and small commercial buildings. The ultimate beneficiaries are the owners
of buildings in which better heating appliances are to be installed and sustainable low
emission solutions are to be provided.
Numerical
1529-RP Full- FrequencyLined DuctsModeling of Sound Transmission in and
Radiation from
September 2012 – March 2014; Secat, Inc..; Principal Investigator, David W. Herrin; TC 2.6, Sound and Vibration Control

The objective of this project is to develop procedures to enable first-principles analytical
acoustic models that will ultimately unify all of the empirical data in the handbook—as
well as data from the various research projects upon which they were based—and extend
the results to a wider variety of duct element configurations and frequency ranges. The
models will combine the in-duct acoustic attenuation and breakout noise components
that are treated separately in the Handbook.
A Heat Transfer
1535-RP Reynolds Numberand Friction Factor Correlation for Low Air-Side
Applications of Compact Heat Exchangers
April 2012 – March 2014; Florida International University; Principal Investigator, Cheng-Xian Lin; TC 8.4, Air-to-Refrigerant Heat
Transfer Equipment; AHRTI $41,000 co-funder

The objective of this research is to develop airside heat transfer and pressure drop
correlations for high performance compact heat exchangers under low air velocity conditions. ASHRAE members who design large refrigerant-to-air condensers, especially
residential A/C and commercial rooftop applications, will benefit from this work. Other
ASHRAE members who design medium temp (refrigeration) and low temp (freezer) vapor
compression systems will be affected, and will benefit even from the development of dry
(frost-free) correlations. Automotive heat exchanger manufacturers could also benefit
from this work by applying it to automotive condenser at idling conditions. Depending
on the region where the automobile is sold, it could spend most of its operating life in the
idle condition (i.e. at stop lights and in traffic jams). Heat exchanger manufacturers who
supply OEM customers or system manufacturers will also be affected, since larger coils
are needed to meet the higher efficiency ratings required in industry. It is estimated
over 50% of the society members could be aided by having such a correlation available
for use in their heat exchanger design tools. If lower airflow off peak conditions begins
to be regulated more closely, even more members could benefit from this work. After
successful completion of the work, such correlations could be implemented by members
immediately. Guidance from new convective data at these low airflows will help facilitate
more efficient design of optimal louver-fin-pitch for AC system, freezer and refrigeration
applications. Having these tools available will enable designers to produce more energy
efficient systems and heat exchangers.

1544-RP Establishing Benchmark Levels and Patterns of Commercial Building
Hot Water Use
April 2010 – August 2014; Applied Energy Technology Company; Principal Investigator, Carl Hiller; TC 6.6, Service Water Heating
Systems

The information available with which designers size and lay-out hot water systems in
the commercial sector is antiquated and sadly in need of updating. We also need a better understanding of how people use water in commercial and institutional buildings.
The objective of this project is to obtain measured hot water use in a sampling of
significant building types that will enable Table 7 of the Service Water Heating chapter
of the ASHRAE Handbook to be revised and updated. High time resolution monitoring
of hot water use will enhance the understanding of the diversity (how many uses occur
at the same time) of hot water uses by providing data on number, timing and duration of
draws, rather than just aggregate water use over long (e.g., day, week, month) periods.

September 2012 – August 2014; University of Texas - Austin; Principal Investigator, Atila Novoselac; TC 5.3, Room Air
Distribution

CO2-based
1547-RP Systems Demand Controlled Ventilation for Multiple Zone HVAC
September 2010 – January 2014 (P); University of Nebraska – Lincoln; Principal Investigator, Josephine Lau; TC 4.3, Ventilation Requirements and Infiltration

ASHRAE Standard 90.1 defines demand controlled ventilation (DCV) as a system that
provides “automatic reduction of outdoor air intake below design rates when the actual
occupancy of spaces served by the system is less than design occupancy.” Standard 90.1 has
required DCV, with some exceptions, for densely occupied spaces since the 1999 version,
which also required that the DCV system be in compliance with ASHRAE Standard 62.1.
The Standard 62.1 User’s Manual includes an appendix showing the underlying theory
and a control scheme for using carbon dioxide (CO2) concentration for DCV in accordance
with the Ventilation Rate Procedure (VRP) of ASHRAE Standard 62.1. The 2007 version
of the Manual only addresses CO2 DCV for single zone systems. The 2004 version of the
Manual also included an approach for multiple zone recirculation HVAC systems (MZS)
but errors were found in the approach so it was removed. The authors of the Manual and
the SSPC 62.1 subcommittee monitoring the Manual’s development felt that before any
MZS DCV control logic could be included in the manual, research had to be done to ensure
that the many complexities of the subject were properly addressed. Until questions are
answered concerning MZS DCV, CO2 DCV cannot be properly implemented in MZS with
any assurance that it will be Standard 62.1 compliant and provide significantly improved
energy performance. This research will ensure that it is possible to fully comply with both
Standard 90.1 and Standard 62.1 with respect to multiple zone DCV systems.
Thermal
1550-RP Ductwork Performance of Insulating Coatings on Piping and
September 2011 – November 2013 (P); R&D Services; Principal Investigator, David Yarbrough; TC 1.8, Mechanical Systems
Insulation

Thermal Insulating Coatings are sometimes used to provide thermal insulation for
pipes, ducts, and tanks. These materials have been on the market for a number of years
and have been defined (Hart 2006) as “a liquid or semi-liquid suitable for application to
a surface in a thickness of 30 mils or less per coat, that dries or cures to form a protective
finish and provide resistance to heat flow”. The ASHRAE Handbook of Fundamentals
(Chapter 26) currently contains no information on these coating materials. Manufacturers of these materials, who would normally provide this information, have not done so
to date. The objective of this project will be to develop thermal conductivity and surface
emittance data for commercially available thermal insulating coatings. The objective of
this project will be to develop thermal conductivity and surface emittance data for three
representative thermal insulating coating products. Testing of three representative
products will give some measure of the variability between products.

1556-RP

Characterization of Liquid Refrigerant Flow Emerging from a Flooded
Evaporator Tube Bundle

September 2012 – March 2014; Kansas State University; Principal Investigator, Steven Eckels; TC 1.3, Heat Transfer and
Fluid Flow

The primary objective of the research will be to experimentally determine the size
distribution, velocity, and outflow and drop back of liquid refrigerant droplets emerging
from the top of the tube bundle in a flooded evaporator. A parametric study is to be carried
out to quantify the effects of surface geometry, fluid properties, and operating conditions
on the droplet size distribution, velocity, and egress and regress.

1557-RP

Lab Comparison of Relative Performance of Gas Phase Filtration Media
at High and Low Challenge Concentrations

August 2011 – January 2014 (P); Syracuse University; Principal Investigator, Jianshun Zhang; TC 2.3, Gaseous Air Contaminants and Gas Contaminant Removal Equipment

Gas phase air filtration equipment (GPAFE) is traditionally and principally applied 1)
in museums, libraries, archives, and other buildings where ambient pollution can present problems for occupants or holdings; 2) in buildings or industrial office areas having

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ASHRAE Journal - October 2013

Table of Contents for the Digital Edition of ASHRAE Journal - October 2013
