RE SE ARCH
Recently Completed Projects and Deliverables
Recent ARF-funded research has produced important new information that has already made its way into various IIAR standards and publications. Following are some examples of how the IIAR Research Committee has put ARF funding to good use.
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A record number of attendees participated in the CFD research panel held at the IIAR conference last March. Many indicated that this is the best research program ever initiated by the Foundation! They were impressed with the complexity of the analysis and the productive results provided in the statistical analysis methods.”
CFD Simulation of an Ammonia Dispersion Event Within Refrigerated Spaces Deliverables: Scientific justification for current ammonia detection requirements plus the addition of a new informative Appendix A to IIAR-2. Summary: Historically, ammonia detection has been required by IIAR-2 as well as the model codes, however, specific guidance on the appropriate number and placement of ammonia detectors for a given type and size of space was not given. Applying Computational Fluid Dynamics (CFD) analysis to answer a number of questions related to the appropriate number and placement of detectors in various types of refrigerated spaces was the object of the study. Principal Researcher, William Greulich, of Kensington Consulting conducted the research and delivered the results of the work in 2020 with a wellreceived technical paper and presentation at the IIAR annual conference.
Wayne Wehber, IIAR Research Chair
than one detector in each room would not be justified. For example, an additional detector on average would reduce detection time by only a few minutes in a large room. Adding more detectors would only reduce response time by a few seconds. It was concluded that the actual leak response (action taken by either plant personnel or in some cases automatic system reaction) would not be significantly improved by the addition of detectors. In summary, the Safety Committee used the study to reinforce the requirements that are already included in IIAR-2 and made no new requirements for additional detectors. The study also showed that detector placement is not extremely critical, but that placement can influence response time. The study is referenced in the latest IIAR-2 informative Appendix A to aid people with complying with the requirement that detectors be “mounted in a position where ammonia from a leak is expected to accumulate”.
Development of a Mechanical Insulation Installation Guideline for Refrigeration Applications Deliverables: A new currently available IIAR Guideline. The information from the project will also be included in future revisions to the Piping Handbook. Summary: Mechanical (pipe, tank, and equipment) insulation The results of the study were used by the Standards Committee to determine if there was merit in requiring additional detectors beyond the minimum requirement of one in every room with ammonia equipment. The study showed that having additional detectors would indeed reduce detection time, however, the reduction was small enough that it was determined that the addition of more
is a critical contributor to energy efficiency and process control in cold applications. Water and water vapor intrusion into these insulation systems is their main failure mechanism. The resistance of the insulation system to water is controlled by the materials used and the quality of the installation. Water resistance of the insulation and vapor retarder materials is well understood but the impact of joints and terminations in these materials and the role installation plays in the water resistance of the insulation system has not been
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well studied.
