Share

A comprehensive model for an oil-free carbon dioxide compressor using Sanderson Rocker Arm Motion (S-RAM) driving mechanism.

Number: pap. F08

Author(s) : YANG B., KURTULUS O., GROLL E. A.

Summary

The multi-piston axial reciprocating compressor using the Sanderson-Rocker Arm Motion (S-RAM) mechanism is expected to have high volumetric efficiencies compared to conventional reciprocating compressors due to the application of a new type of seal to prevent the in-cylinder refrigeration gas leaking through the clearance between piston and cylinder wall. In addition, the compressor is expected to have high energy efficiencies compared to swash-plate/wobble-plate compressors due to reduced friction using the S-RAM mechanism and a near perfect linear motion of the piston inside the cylinder. Furthermore, the compressor capacity can be controlled by adjusting the piston stroke instead of compressor speed to meet the requirements of the delivered mass flow rate in the field. A comprehensive simulation model for a prototype reciprocating compressor using the S-RAM mechanism has been developed. The natural refrigerant carbon dioxide (CO2) is used as the working fluid. The comprehensive model is comprised of a kinematics model, compression process model, dynamics model and an overall energy balance model. In the kinematics model, the movement of the piston is given including its displacement, velocity and acceleration. In the compression process model, the system of governing equations is solved to obtain the instantaneous refrigerant temperature and pressure inside the cylinder. A new leakage model for the rubber-like seal is incorporated into the compression process model. The variations of suction and discharge valve movements with respect to driving shaft rotational angle are also revealed. The values of the cylinder wall temperature, the actual suction and discharge temperatures in the connecting pipes,which are required to initiate the solving of the compression process model,are given by the overall energy balance. A lumped temperature assumption is employed in the overall energy balance model to assume there is no temperature gradient in each compressor component at steady-state. The dynamics model uses the in-cylinder refrigerant pressure determined from the solution of the compression process model to calculate the forces/moments of the driving mechanism. The whole simulation model is numerically solved using RKF45 and Broyden’s method within a specified convergence range.

Available documents

Format PDF

Pages: 12

Available

  • Public price

    20 €

  • Member price*

    15 €

* Best rate depending on membership category (see the detailed benefits of individual and corporate memberships).

Details

  • Original title: A comprehensive model for an oil-free carbon dioxide compressor using Sanderson Rocker Arm Motion (S-RAM) driving mechanism.
  • Record ID : 30022101
  • Languages: English
  • Source: 8th international conference on compressors and refrigeration, 2017.
  • Publication date: 2017/07/20

Links


See other articles from the proceedings (97)
See the conference proceedings

Indexing