Key
1248
Conference Year
2014
Keywords
VCC reciprocating compressors, helical oil pump, oil supply system, low speed
Abstract
Compressors with variable capacity are employed in domestic applications where better performance, fine temperature control, low power consumption and low noise levels are required. This is achievable not only by the use of an electronic inverter drive capable of operating at different frequencies, but also by technology applied in mechanical, electrical, acoustic and thermodynamic subsystems, making possible to control its cooling capacity, fully meeting the product requirements. One fundamental condition of operation is to ensure proper lubrication of mechanical components, for 100% of compressors, operating throughout its speed range, ensuring full operation throughout its lifetime. To do that, several methods are used to pump the oil towards the bearings. This task is easily performed when the compressor’s crankshaft has high kinetic rotating energy. On the other hand, it becomes a challenge when compressor operates at lower speeds. In this case, computational techniques, using numerical methods in commercial simulators, have aided on designing oil pumping devices that maximizes the oil flow rate. Through numerical and experimental techniques, this study aims to propose a simplified, uncoupled simulation model for the compressor oil supply system. The primary response variable is the volumetric oil flow rate of a helical pump, regarding the following analysis factors: a) the immersion depth and b) shaft rotation. Numerical results from uncoupled proposed model have shown good agreement with experimental data.