This paper presents the experimental research into the evaluation of lubricity for polyolester (POE) lubricant with HFC-134a refrigerant in rotary and reciprocating compressors for household refrigerators. In order to evaluate the lubricity for POE lubricant with HFC-134a refrigerant, we conducted 4-balls wear tests in the mixing environment of POE lubricant and HFC-134a refrigerant. In the pre...

Title of Document: INVESTIGATION OF HOUSEHOLD REFRIGERATOR WITH ALTERNATIVE LOW GLOBAL WARMING POTENTIAL REFRIGERANTS Daniel Thomas Leighton, Master of Science, 2011 Directed By: Professor Reinhard Radermacher, Mechanical Engineering Steady-state and transient thermodynamic models of the refrigeration system were created in order to predict the performance of household refrigerators using diffe...

In this work, new thermodynamic models for refrigerant mixtures are provided the binary pairs R-1234yf/134a, R-1234yf/1234ze(E), and R-134a/1234ze(E) based on reference measurements of speed sound, density, bubble-point pressures. Fitting very accurate liquid-phase sound density data reproduces pressures to within close their uncertainty, yielding deviations in less than 0.1% 1% (and R-1234yf/1...

MAXIFLO-125 Inhaler Each actuation delivers: Formoterol Fumarate Dihydrate IP..................6 mcg Fluticasone Propionate IP............................125 mcg Suspended in propellant HFA 134a ...............q.s. MAXIFLO-250 Inhaler Each actuation delivers: Formoterol Fumarate Dihydrate IP .................6 mcg Fluticasone Propionate IP...........................250 mcg Suspended in propella...

In this study, condensation heat transfer experiments were conducted with two types of plate and shell heat exchangers (P&SHE) using R-134A. An experimental refrigerant loop has been established to measure the condensation heat transfer coefficient of R-134A in a vertical P&SHE. Two vertical counter flow channels were formed in the P&SHE by stacking three plates of geometry with a corrugated tr...

The design of small satellite propulsion systems is often a constant struggle to balance two opposing requirements: system performance and system safety. Cold gas thruster systems utilizing the refrigerant R-134a as a two-phase propellant have the potential to meet both the performance goals and safety requirements. This paper delineates a safety analysis for a general R-134a-based propulsion s...

Oil return from the evaporator to the compressor suction port is an important requirement. It is affected by the refrigerant/lubricant properties, gas velocities and piping geometry. The refrigerant R -134a has successfully replaced R-12 in household refrigerators and freezers. This paper describes a test method to estimate the mean oil film thickness and to observe the flow pattern in vertical...

HCFC-22 (CHClF2) and HFC-134a (CH2FCF3) are two major gases currently used worldwide in domestic and commercial refrigeration and air conditioning. HCFC-22 contributes to stratospheric ozone depletion, and both species are potent greenhouse gases. In this work, we study in situ observations of HCFC-22 and HFC-134a taken from research aircraft over the Pacific Ocean in a 3-y span [HIaper-Pole-to...

BACKGROUND Current pressurised metered dose asthma inhaler (pMDI) propellants are not inert pharmacologically as were previous chlorofluorocarbons, have smooth muscle relaxant' partial pressure effects in the lungs and inhaled hydrofluoroalkane 134a (norflurane) has anaesthetic effects. Volumes of propellant gas per actuation have never been measured. METHODS In-vitro studies measured gas vol...