Refrigeration and Air Conditioning

Research is shaped around Urban Engineering specialists who collaborate to pursue a range of applied research themes. Current themes of interest are looking at:

Ground coupled cooling

The team has carried out extensive work looking at the potential of using the ground as a latent cooling resource in the UK. They've pioneered using this sustainable resource in a number of high profile prototype applications and have investigated the feasibility and economics of specific solutions that have led to experimental testing. Key to using the technology is the adopting of low capital cost solutions, a number of which have been proposed by the centre.
The team is working closely with geotechnical colleagues to investigate the potential for large-scale energy storage schemes and adopting the system in conjunction with other polygeneration systems with diurnal variations. The team's work in this area has been widely reported in both the international and national media.

Heat powered cycles

Their fundamental work in the area of absorption refrigeration thermodynamics has been internationally reported and was incorporated into the latest ASHRAE Handbook. This has enabled studies in combined cooling, heat and power (CCHP) to be reflected in modern thinking so that cogeneneration schemes are now seen as a major component in the UK Government's strategy to reduce greenhouse gas emissions.
The team has pioneered new studies in sustainable cooling involving the theoretical and experimental investigation of modern cooling tower technology as a sustainable cooling resource. They've also investigated large scale use of cooling, heat and power and pioneered integration polygeneration techniques including use of waste heat to desalinate waste water.

Refrigeration systems and technology

The team is a world leader in the use of air as a refrigerant and have used air as a benign and natural refrigerant in a number of applications including food processing in the areas of cooking, cooling, fast freezing, retail display and in building air conditioning.
They've researched refrigeration systems and technology to reduce CO2 emissions and developed systems that incorporate night storage of energy using Phase Change Materials (PCMs) – improving the efficiency of control systems through PCM integration. They are currently developing a high efficiency, pumpless absorption chiller; technology that offers significantly improved efficiency compared with traditional heat powered cooling methods.
With an estimate of 85million incidences of food poisoning a year in the UK and US there has been a lot of interest in the team's two patents in the area of food display. The team has successfully addressed the problem of refrigerant leakage and CFC replacement leading to an international acceptance of hydrocarbons in place of ozone depleting chemicals. This brought about the revision BS EN378 and created a new business area for Calor UK. This resulted in the team now advising McDonalds Corporation on worldwide application.

Modelling, Thermoeconomics and Optimisation

The team has had major impact in the case of mathematical modelling, pioneering dynamic modelling of refrigeration systems which has gone on to become a widely used tool. Their modelling work has continued with applying Thermoeconomics to building energy problems. Optimisation studies have reduced energy usage in complex energy systems by 35% without incurring any additional expense. Modelling has also led to the seminal international study of compressor control by frequency modulation software that has resulted in greatly improved air conditioning performance.
The team's examination and new understanding of retail food display refrigeration for food retailer Sainsbury's has resulted in a number of new methods being adopted by the industry, improved food hygiene and a tenfold reduction in operating costs. They've identified the need for better modelling systems for underground railways, particularly in simulation of low energy technologies and are currently developing an industry-led software tool.
Mathematical models have been developed to understand complex interaction within the food cold chain. These include dynamic models of food storage and food freezing and chilling operations. The team has extensive experience of using Computational Fluid Dynamics (CFD) modelling to optimise and develop retail, commercial and domestic refrigeration systems.

Food refrigeration

The team has wide ranging expertise in food refrigeration, with a detailed knowledge of both food quality and safety and refrigeration systems operation. They're uniquely placed to understand and optimise both food quality and refrigeration equipment operation. Plus, they have extensive experience in developing, optimising and testing food refrigeration systems and equipment in all areas of the food cold chain.
Typical projects include: optimising food refrigeration equipment and facilities (food processing, cold storage, retail display, commercial and domestic refrigeration), use of Vacuum Insulated Panels (VIPs), reducing infiltration in cold store entrances, reducing waste in the home, humidification to improve food quality, optimisation of food cutting technologies and design and development of novel food refrigeration systems.

Energy

Reducing energy is a vital part of the team's activities. They've worked throughout the food cold chain to identify options to reduce energy consumption in areas such as domestic refrigeration, improving staff training for commercial clients and developing energy efficient environmental refrigeration systems. They're currently investigating benchmarking refrigeration system performance in collaboration with the Institute of Refrigeration – this is particularly important as refrigeration and air conditioning is used extensively worldwide and is responsible for over 10% of worldwide CO2.

Project links

The team has been awarded EU funding to help develop innovative, environmentally friendly technology to contribute towards the fight against climate change. The project, Improving Cold Storage Equipment in Europe (ICE-E) involves nine partners and examines ways to reduce energy use in food cold storage, reducing the impact of refrigeration on global warming.

Contact

Prof Graeme Maidment
Tel: 020 7815 7626
Email: maidmegg@lsbu.ac.uk