Developing Control Logic for a High-Pressure Fog Cooling System Operation for a Naturally Ventilated Greenhouse

• HANDARTO

  <I>Department of Bioproduction Science, Faculty of Horticulture, Chiba University</I>

• HAYASHI Makio

  <I>Department of Biological Science and Technology, School of High-technology for Human Welfare, Tokai University</I>

• OHYAMA Katsumi

  <I>Arid Land Research Center, Tottori University</I>

• TOIDA Hiromi

  <I>Department of Bioproduction Science, Faculty of Horticulture, Chiba University</I>

• GOTO Eiji

  <I>Department of Bioproduction Science, Faculty of Horticulture, Chiba University</I>

• KOZAI Toyoki

  <I>Department of Bioproduction Science, Faculty of Horticulture, Chiba University</I>

Abstract

An effective control logic for a high-pressure fog cooling system for a naturally ventilated greenhouse has been developed. A suitable duration of the fog cooling system operating time is estimated using weather data and the target relative humidity inside the greenhouse with a computational model based on mass and thermal balances of the greenhouse air. The program has three main tasks: (1) to read the dry bulb temperature set point inside the greenhouse for fogging system operation and the target relative humidity defined by the user; (2) to compute a suitable duration of the fog cooling system operation; and (3) to display relevant output information to the user. The duration of fog cooling system operation decreased as the water vapor pressure deficit inside the greenhouse decreased. The control logic of the fog cooling system would be used to lower dry bulb temperature by increasing the relative humidity to the target value. Our results prove that implementing this control logic for greenhouse fog cooling system is technically feasible.

Journal

• Environment Control in Biology

  Environment Control in Biology 44 (1), 1-9, 2006

  Japanese Society of Agricultural, Biological and Environmental Engineers and Scientists

Keywords

• air temperature
• environmental control
• fogging rate
• relative humidity

Details

• CRID: 1390001205260756352
• NII Article ID: 130003856962
• NII Article ID: 10026885778
• NII Book ID: AA12029220
• DOI: 10.2525/ecb.44.1
• ISSN: 18830986
• ISSN: 1880554X
• NDL BIB ID: 7855066
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I7855066
• Text Lang: en
• Data Source:
  • JaLC
  • NDL
  • Crossref
  • CiNii Articles
• Abstract License Flag: Disallowed