Geometrical model of a screw vacuum pump

Vacuum Gauge to Vacuum Pump Valve

investigating the feasibility of a proposed model for geometric design of deployable arch structures

deployable scissor type structures are composed of the so-called scissor-like elements (sles), which are connected to each other at an intermediate point through a pivotal connection and allow them to be folded into a compact bundle for storage or transport. several sles are connected to each other in order to form units with regular polygonal plan views. the sides and radii of the polygons are...

Screw Compressors for Heat Pump Application

Development of Mathematical Model for Controlling the Drilling Parameters with a Screw Downhole Motor

Article presents results of study on possibility of increasing the efficiency of drilling directional straight sections of wells using screw downhole motors (SDM) with a combined method of drilling with rotation of drilling string (DS). Goal is to ensure steady-state operation of SDM with simultaneous rotation of DS by reducing the amplitude of oscillations with adjusting the parameters of dril...

Optimum Rotor Geometrical Parameters in Refrigeration Helical Twin Screw Compressors

This paper presents a parameter study for optimum rotor geometrical parameter combinations of a refrigeration helical twin screw compressor with four commonly used lobe combinations and five different length/diameter ratios and wrap angles. The volumetric and indicated efficiencies of the compressor are important. So also are other factors such as rotor deflection, bearing load, bearing life an...