The Climatic Wind Tunnel (CWT) is a facility used by the motor industry to test
vehicles under climatic extremes without the need for expensive overseas test
This work focuses on the application of computer simulation to the Heating
Ventilation and Air Conditioning (HVAC) plant that makes up a CWT facility. The
objective being to reduce its operational costs through the identification of energy
saving operational strategies.
When in operation the CWT has a peak power consumption of 3MW. The
implementation of any measures that would reduce this peak load would give rise to
considerable savings in the operating costs of the facility.
Computer simulation is an accepted technique for the study of systems operating
under varying load conditions. Simulation allows rapid analysis of different strategies
for operating plant and the effectiveness of achieving the desired effect without
compromising the buildings performance.
Models for the components of the CWT have been developed and coded in Neutral
Model Format. These models have then been linked together in a modular simulation
environment to give a model of the complete plant. The CWT plant naturally
decomposesin to four major subsystems these being the test chamber, the soakroom,
air make-up and refrigeration system. Models of all the primary and secondary HVAC plant are described as is how they
constitute the systems that make up the CWT. Validation tests for individual
components as well as for the systems have been carried out.
To illustrate the potential of the application of computer simulation into finding
improved modes of operation that would reduce the energy consumption of the
facility, four studies have been carried out. The studies involve the possibility of
scheduling the operation of condenser fans as a function of refrigeration load and
outside ambient temperature, methods for the pre-test conditioning of a vehicle, a
reduction in the secondary refrigerant flow temperature and an increase in the
thickness of the insulated panels from which the facility is constructed. The studies
carried out showed that there was potential for moderate energy savings to be made
in the operation of the facility and that extended simulation runs would allow for the
in-depth assessment of a large range of possible modes of plant operation in order to
identify the areas where the greatest savings are possible.
A Doctoral Thesis. Submitted in partial fulfillment of the requirements for the award of Doctor of Philosophy of Loughborough University.