Boiling of mixtures in channels is involved many chemical processes, and refrigerant are finding a rapidly increasing use the refrigeration industries. Hence, reliable prediction CHF (critical heat flux) needed. There no published method that has been verified over wide range parameters. In this study, available data for tubes annuli were compared to general correlations annuli, which well-veri...

Vapour-liquid equilibria (VLE) data are within the most important experimental data to correctly represent the mixtures' behaviour at the saturation boundaries. In the last years, the VLE of several new binary mixtures have been studied by our group in order to find possible alternatives for the traditional refrigerants. The data have been correlated with the Lemmon-Jacobsen model, which is the...

Kim, Woohyun. Ph.D., Purdue University, December 2013. Fault Detection and Diagnosis for Air Conditioners and Heat Pumps based on Virtual Sensors. Major Professor: James E. Braun, School of Mechanical Engineering. The primary goal of this research is to develop and demonstrate an integrated, on-line performance monitoring and diagnostic system with low cost sensors for air conditioning and heat...

Selection of spiral capillary tube for refrigeration appliances and the effect of changes in the parameters such as capillary tube dimensions i.e. capillary tube diameter, coil pitch, capillary tube length and inlet conditions of refrigerant to the capillary tube i.e. degree of subcooling, inlet pressure on the mass flow rate of the refrigerant, also investigation about the coiling effect of sp...

This work presents an experimental approach to study the refrigerant flow through capillary tube-suction line heat exchangers. Lateral heat exchanger performance with refrigerant HFC-134a was experimentally evaluated for a range of heat exchanger assemblies and operating conditions typically found in household refrigerators and freezers. Based on the resulting performance data base, the influen...

Models for unitary air conditioners and heat pumps typically have difficulties in providing accurate predictions for the following situations: 1) charge modeling over a large range of charge levels, 2) two-phase refrigerant entering fixed-orifice expansion devices, 3) two-phase refrigerant entering compressors, and 4) non-uniform refrigerant mass flow allocation among evaporator circuits at low...

Refrigeration oil and other materials used with refrigerant for refrigerators or air conditioners should have thermal and chemical stability to maintain the system reliability. Some kinds of synthetic oil are used for alternative refrigerant, HFC’s and hydrolysis, material compatibility, and low-temperature extraction of contaminant or sludge are important subjects. Much more numbers and times ...

More than one year has passed since refrigerant for refrigerator was changed from CFC12 to HFC134a. Long term reliability of refrigerator in HFC134a refrigerant system is mainly dependent on lubrication of moving parts of compressor and clogging of capillary tube. To maintain better practical reliability in components in compressor such as refrigeration lubricant,metallic materials and motor in...

Fin-tube heat exchangers are widely used in air-conditioners and heat pumps, which are constructed with a lot of tubes. Refrigerant circuit of heat exchanger with numerous pipe can be constructed by many methods. Refrigerant circuit design is usually determined designer’s experience and case by case test without guides. The number of path affects largely on heat exchanger performance. In this p...