Abstract
This paper describes design and optimization of a Waste
Heat Recovery Unit (WHRU) for a power cycle which uses
CO2 as a working fluid. This system is designed for offshore
installation to increase gas turbine efficiency by recovering
waste heat from the exhaust for production of additional power.
Due to severe constraints on weight and space in an offshore
setting, it is essential to reduce size and weight of the
equipment to a minimum. Process simulations are performed to
optimize the geometry of the WHRU using different objective
functions and thermal-hydraulic models. The underlying heat
exchanger model used in the simulations is an in-house model
that includes the calculation of weight and volume for frame
and structure for the casing in addition to the thermal-hydraulic
performance of the heat exchanger core. The results show that
the for a set of given process constraints, optimization with
respect to minimum total weight or minimum core weight
shown similar results for the total installed weight, although the design of heat exchanger differs. The applied method also shows how the WHRU geometry can be optimized for different material combinations
Heat Recovery Unit (WHRU) for a power cycle which uses
CO2 as a working fluid. This system is designed for offshore
installation to increase gas turbine efficiency by recovering
waste heat from the exhaust for production of additional power.
Due to severe constraints on weight and space in an offshore
setting, it is essential to reduce size and weight of the
equipment to a minimum. Process simulations are performed to
optimize the geometry of the WHRU using different objective
functions and thermal-hydraulic models. The underlying heat
exchanger model used in the simulations is an in-house model
that includes the calculation of weight and volume for frame
and structure for the casing in addition to the thermal-hydraulic
performance of the heat exchanger core. The results show that
the for a set of given process constraints, optimization with
respect to minimum total weight or minimum core weight
shown similar results for the total installed weight, although the design of heat exchanger differs. The applied method also shows how the WHRU geometry can be optimized for different material combinations
