Numerical investigation of natural convection in a mono-span greenhouse

Sunita Kruger, Leon Pretorius

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review

5 Citations (Scopus)

Abstract

In this paper, the use of computational fluid dynamics is evaluated as a design tool to investigate the indoor climate of a confined greenhouse. The finite volume method using polyhedral cells is used to solve the governing mass, momentum and energy equations. Natural convection in a cavity corresponding to a mono-span venlo-type greenhouse is numerically investigated using Computational Fluid Dynamics. The CFD model is designed so as to simulate the climate above a plant canopy in an actual multi-span greenhouse heated by solar radiation. The aim of this paper is to investigate the influence of various design parameters such as pitch angle and roof asymmetry and on the velocity and temperature patterns inside a confined single span greenhouse heated from below. In the study reported in this paper a two-dimensional CFD model was generated for the mono-span venlo-type greenhouse, and a mesh sensitivity analysis was conducted to determine the mesh independence of the solution. Similar two-dimensional flow patterns were observed in the obtained CFD results as the experimental results reported by Lamrani et al [2]. The CFD model was then modified and used to explore the effect of roof pitch angle and roof asymmetry at floor level on the development of the flow and temperature patterns inside the cavity for various Rayleigh numbers. Results are presented in the form of vector and contour plots. It was found that considerable temperature and velocity gradients were observed in the centre of the greenhouse for each case in the first 40mm above the ground, as well as in the last 24mm close to the roof. Results also indicated that the Rayleigh number did not have a significant impact on the flow and temperature patterns inside the greenhouse, although roof angle and asymmetry did. The current results demonstrate the importance of CFD as a design tool in the case of greenhouse design.

Original languageEnglish
Title of host publicationASME 2012 11th Biennial Conference on Engineering Systems Design and Analysis, ESDA 2012
Pages91-100
Number of pages10
DOIs
Publication statusPublished - 2012
EventASME 2012 11th Biennial Conference on Engineering Systems Design and Analysis, ESDA 2012 - Nantes, France
Duration: 2 Jul 20124 Jul 2012

Publication series

NameASME 2012 11th Biennial Conference on Engineering Systems Design and Analysis, ESDA 2012
Volume2

Conference

ConferenceASME 2012 11th Biennial Conference on Engineering Systems Design and Analysis, ESDA 2012
Country/TerritoryFrance
CityNantes
Period2/07/124/07/12

ASJC Scopus subject areas

  • Control and Systems Engineering
  • Mechanical Engineering

Fingerprint

Dive into the research topics of 'Numerical investigation of natural convection in a mono-span greenhouse'. Together they form a unique fingerprint.

Cite this