Abstract

Heat ventilation and Air Conditioning (HVAC) systems are used in 87% of homes in the US, and represent on average 12% of household expenditures. This breadth of usage means that even small changes in technology can have a huge impact on the footprint of HVAC systems on our environment. Such an impact has led to the progressive ban of Ozone depleting refrigerants in chiller circuits following the Montreal Protocol and Kigali Amendment agreements. This change is affecting the performance of the chiller circuit, and therefore motivating a re-dimensioning or re-design of the full HVAC system. Aside from the chiller circuit, fans themselves are typically responsible for 34% of the average energy consumption of HVAC systems, and are therefore a good subject of work when targeting improved overall system efficiency. Hence, effective design of efficient fans would require iterating towards a better design, typically leveraging a three-dimensional simulation of a rotating geometry. Furthermore, the performance of these fans is highly dependent on the integration to the full HVAC system. In the US, the Spawn-of-EnergyPlus engine is even encouraging HVAC manufacturers to go beyond the design of the HVAC itself, and verify the building integrated HVAC performance directly to minimize energy consumption. Tackling these types of issues often requires representing the HVAC system performance as a set of 1D reduced-order-model nodes. Meeting these types of energy efficiency objectives requires a new approach to system integrated component design. In this paper, we will present aspects of such a design loop, focusing on the aerodynamic and aero-acoustic CAD driven optimization of an axial fan In a second part of the paper, we will include the impact of the fan design in the overall HVAC system performance, represented as a reduced order 1D model. We will show that such development can be organized effectively using a centralized platform, ensuring all key requirements are met.