This paper presents generic equipment models that capture the performance of families of similar heat pumps equipment and that can be used in building simulation programs. Mapping has been carried out for families of single and dual compressor speed ducted split systems and the correlations are being implemented as components for building simulation. The units mapped ranged in nominal capacity ...

The presence of liquid refrigerant in the compressor cylinder during operation, or liquid slugging, is one of the most common causes of failure in reciprocating compressors. We propose to detect this fault by analyzing the electrical current flowing into the compressor and identifying the change in the load on the motor caused by the presence of liquid in the compressor cylinder. Two different ...

The paper focuses on the operation of simple refrigeration cycles. With equipment given, there are, from a control and operational point of iew, five steady-state degrees of freedom; the compressor power, the heat transfer in the condenser, the heat transfer in the evaporator, the choke alve opening and the active charge in the cycle. Different designs for affecting the active charge, including...

Inverse models are generally derived from empirical behavior and expressed in terms of one or more driving forces and a set of empirical parameters that are “identified” using measurements. Once identified, a model can be used for a variety purposes, including performance monitoring, diagnostics, retrofit analysis, measurement and verification of efficiency improvements, and on-line control opt...

Investigating alternative system configurations is a means to improving vapor compression system COP by increasing system capacity and reducing compressor power consumption. The characterization and optimization of alternative system configurations can be conducted through the use of simulation. This paper presents a vapor compression system simulation tool capable of modeling a two-stage flash...

Air pre-cooling equipment is normally being employed in air-conditioning systems for pre-cooling the ambient outdoor air to enhance the air-conditioning systems performance. In this study, the potential of a passive water-to-air heat pipe based heat exchanger (HPHEX) for air pre-cooling purpose in air-conditioning systems for the high cooling load demanding regions of Iran was investigated. To ...

In this paper, the experimental vibration analysis of a single cylinder air compressor based on a hypocycloid straight line mechanism (HSM) is investigated. The HSM mechanism uses planetary gears to convert rotational motion to purely linear motion. In the conventional air compressor, the slider- crank mechanism is replaced by the HSM mechanism with appropriate counterweights. The constructed s...

The design and dynamic characterization of a free piston compressor is presented in this paper. The free piston compressor is a proposed device that utilizes combustion to compress air into a high-pressure supply tank. The device is configured such that the transduction from thermal energy to stored energy, in the form of compressed gas, is efficient relative to other small-scale portable power...

The chilled-water systems, mainly consisting of electric chillers and cooling towers, are crucial for the ventilating and air conditioning systems in commercial buildings. Energy efficient operation of such systems is thus important for the energy saving of commercial buildings. This paper presents an extremum seeking control (ESC) scheme for energy efficient operation of the chilled-water syst...

The system design of window air conditioner does not evolve in one day. Due to the continous efforts are taken by the refrigeration and air conditionging professionals, successful and economic models of window air conditioners are currently used. This paper states about the development of window air conditioner with phase change material and water as refrigerants. Developed air conditioner was ...