New concepts for the ventilation of shopping centers: Reducing air change rate,applying active chilled beams and elevating cold water supply temperature

Abstract

New concepts of removing the cooling loads in shopping centres are presented in a multi-disciplinary study. In air-quality experiments, we found that the air change rate (ACR) in shops can be reduced significantly, while still maintaining acceptable air quality. Dilution curves of typical odour-intensive retail goods were measured, which show that ACRs can be reduced down to 1.75 h⁻¹ without impacting odour perception significantly. Then, the standard ventilation systems were replaced by air–water systems, namely active chilled beams, which allow for a combined supply of fresh air and heat removal via the water circuit. To realize low ACRs in the shops, experimental studies for developing high-induction active chilled beam systems are presented. Finally, CFD simulations were conducted in a generic shop. Aspects like room air flow, odour propagation and thermal comfort were investigated. The cold water supply was assumed to be generated in a renewable way, leading to high cold water supply temperatures. Feasible ventilation configurations with ACRs as low as 1.1 h⁻¹ have been identified without deteriorating either air quality or thermal comfort. Primary energy consumption was assessed according to German standards and was reduced by up to 67% with the presented approach.