In response to concerns about the contribution of fluorocarbon refrigerants to global climate change, a new, more environmentally sustainable, refrigerant molecule has been developed and is being evaluated. This new molecule is the hydrofluoroolefin 2,3,3,3,-tetrafluoroprop-1-ene, or HFO-1234yf. The molecule has been shown to be stable inside refrigeration equipment, but to quickly decompose if...

In California, commercial refrigeration accounts for 14% of electric energy usage, corresponding to 9,014 GWh per year and affecting more than 110,000 commercial establishments. A single walk-in freezer uses more energy than 5 single-family houses. Despite more stringent standards and utility programs promoting hardware improvements, controls systems used for commercial refrigerators are still ...

This paper deals with a lumped-parameter dynamic simulation of a single-effect LiBr-H2O absorption chiller. In many studies the thermodynamic properties of LiBr-H2O solution were taken from some approximate relations causing the results to be somewhat inaccurate. These relations were used to solve simultaneous differential equations involving the continuity of species constituting the LiBr-H2O ...

Title of dissertation: EXPERIMENTAL AND THEORETICAL INVESTIGATION OF OIL RETENTION IN A CARBON DIOXIDE AIR-CONDITIONING SYSTEM Jun-Pyo Lee, Doctor of Philosophy, 2003 Dissertation directed by: Professor Reinhard Radermacher Department of Mechanical Engineering In a closed loop vapor compression cycle, a small portion of the oil circulates with the refrigerant flow through the cycle components w...

This paper continues and concludes the study of the proposed high-efficiency combined desalination and refrigeration system based on the LiBr–H2O absorption cycle introduced in the paper that is Part 1 [Proposal and analysis of a high-efficiency combined desalination and refrigeration system based on the LiBr– H2O absorption cycle––Part 1: System configuration and mathematical model. Energy Con...

This paper describes an approach for control of an economiser cycle based on the use of economiser pressure as the primary control parameter. In the study, the economiser cycle was used to optimise a multi-temperature indirect (IDX) transport refrigeration system, where hydronic secondary loops were utilised. In transport refrigeration applications, IDX systems can offer the potential to addres...