Modelling of a solar pond as a combined heat source and store to drive an absorption cooling system for a building in Iraq

  • Safwan Kanan

Student thesis: Phd

Abstract

AbstractThe University of ManchesterSafwan Mohammed Jameel Ahmed KananDoctor of Philosophy (PhD)Modelling of a solar pond as a combined heat source and store to drive an absorption cooling system for a building in Iraq23 October 2016This research studies the performance of a salinity gradient solar pond driving an absorption cooling system, as an alternative to a conventional electrically powered cooling system, to provide cool air for a modern single family house in the hot dry climate of Baghdad, Iraq.The system comprises a salinity gradient solar pond, a hot-water-fired absorption water chiller, a chilled-water cooling coil which cools the air in the house, and a cooling tower which rejects heat to the ambient air. Hot brine from the pond circulates through a heat exchanger, where it heats water that is then pumped to the chiller. This arrangement protects the chiller from the corrosive brine. The system is controlled on-off by a room thermostat in the house.The system performance is modelled by dynamic thermal simulation using TMY2 hourly typical weather data. TRNSYS software is used for the main simulation, coupled to a MATLAB model of heat and mass transfer in the pond and the ground beneath it. The model of the pond and the ground is one-dimensional (only vertical transfers are considered). Radiation, convection, conduction, evaporation and diffusion are considered; the ground water at some depth below the pond is treated as being at a fixed temperature. All input data and parameter values in the simulation are based on published, standard or manufacturer's data.Temperature profiles in the pond were calculated and found to be in good agreement with published experimental results.It was found that a pond area of approximately 400 m2 was required to provide satisfactory cooling for a non-insulated house of approximately 125 m2 floor area.It was found that varying the pond area, ground conditions and pond layer thicknesses affected the system performance. The optimum site is one that has soil with low thermal conductivity, low moisture content and a deep water table.It is concluded that Iraq's climate has a potential for solar-pond-powered thermal cooling systems. It is feasible to use a solar-pond-powered cooling system to meet the space cooling load for a single family house in the summer season. Improving the thermal performance of the house by insulation could reduce the required solar pond area.
Date of Award1 Aug 2017
Original languageEnglish
Awarding Institution
  • The University of Manchester
SupervisorJonathan Dewsbury (Supervisor) & Gregory Lane-Serff (Supervisor)

Keywords

  • Salt gradient solar pond; soil thermal properties; solar air-conditioning system; solar cooling;TRNSYS simulation.
  • Absorption chiller;coupled simulation,MATLAB code

Cite this

'