Condensation of NH3 within a plate heat exchanger of small diameter channel

Research output: Chapter in Book/Conference proceedings/Edited volumeConference contributionScientificpeer-review

Abstract

Most plate heat exchangers (PHEs) have hydraulic diameters in the range of 2∼5 mm and show characteristics of both macro-channels and micro-channels. Both gravity and surface tension have non-negligible influences and determine the heat transfer and frictional pressure drop.

This paper investigates NH3 condensation in a PHE with a hydraulic diameter of 2.99 mm. The large surface tension of NH3 enhances the micro-channel characteristics. The heat transfer coefficients (HTCs) are compared with homogeneous and separated models, respectively. Both models have been previously compared with the experimental data of HFCs, hydrocarbons and HFOs. The prediction for NH3 is generally good since the deviations are small, while the sensitivity to mass fluxes and vapor qualities cannot be estimated properly. The data of frictional pressure drop are predicted by a correlation of two-phase Fanning friction factor, which is based on homogeneous flow and includes the influences of mass fluxes, vapor qualities, hydraulic diameters, chevron angles, etc. The fluid properties of NH3 are significantly different between liquid and vapor phases, and the averaged density derived from homogeneous flow is under-estimated. The prediction is improved by calculating the averaged density from the void fraction models of separated flow.
Original languageEnglish
Title of host publicationProceedings of the 6th ASME International Conference on Micro/Nanoscale Heat and Mass Transfer
Place of PublicationNew York, NY, USA
PublisherASME
Number of pages8
ISBN (Print)978-0-7918-5890-5
DOIs
Publication statusPublished - 2019
EventMNHMT2019: 6th ASME International Conference on Micro/Nanoscale Heat and Mass Transfer - Dalian, China
Duration: 9 Jul 201910 Jul 2019

Conference

ConferenceMNHMT2019: 6th ASME International Conference on Micro/Nanoscale Heat and Mass Transfer
CountryChina
CityDalian
Period9/07/1910/07/19

Keywords

  • small diameter channel
  • condensation
  • heat transfer
  • homogeneous flow and separated flow
  • plate heat exchanger
  • NH3

Fingerprint Dive into the research topics of 'Condensation of NH3 within a plate heat exchanger of small diameter channel'. Together they form a unique fingerprint.

  • Cite this

    Tao, X., Kirkenier, J., & Infante Ferreira, C. (2019). Condensation of NH3 within a plate heat exchanger of small diameter channel. In Proceedings of the 6th ASME International Conference on Micro/Nanoscale Heat and Mass Transfer [MNHMT2019-3920] ASME. https://doi.org/10.1115/MNHMT2019-3920