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Engineering
Materials Science

Vapor Compression System Modelica Library for Aircraft ECS

Profile image of Santiago Torras OrtizSantiago Torras Ortiz

2018

Abstract

This work presents a Modelica library aimed to simulate vapor compression systems at both steady and transient conditions. The simulation of these specific systems is particularly challenging from both the phenomena and the numerical resolution point of views. The main goal of the library is to provide, not only accuracy and robustness, but also very low computational time. It is worth mentioning that, although the baseline version of the library is currently operative, its development continues in order to improve or add new features.Most of the components developed for the library are simulated by means of look-up tables or efficiency curves for the sake of quickness. The main efforts were focused on two critical aspects of the system. On the one hand, heat exchanger models were developed based on a switching moving boundary approach in order to have a relatively high ratio between accuracy and resolution time. This method takes into account the distribution of phases along heat e...

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References (10)

  1. Bendapudi, S., Braun, J. E., & Groll E.A. (2008). A comparison of moving-boundary and finite-volume formulations for transients in centrifugal chillers. Int. J. Ref., 31, 1437-1452.
  2. Bonilla, J., Dormido, S., & Cellier, F.E. (2015). Switching moving boundary models for two-phase flow evaporators and condensers. Comm. Nonlinear Science and Numerical Simulation, 20, 743-768.
  3. Casella, F. (2012). On the formulation of steady-state initialization problems in object-oriented models of closed thermo-hydraulic system. Proceedings of the 9th International Modelica Conference, Munich, Germany (215-222).
  4. Desideri, A., Dechesne, B., Wronski, J., V D Broek, M., Gusev, S., Lemort, V., & Quoilin, S. (2016). comparison of moving boundary and finite-volume heat exchanger models in the Modelica language. Energies, 9(5), 339.
  5. Dermont, P., Limperich, D., Windahl, J., Prölss, K., & Kübler, C. (2016). Advances of zero flow simulation of air conditioning systems using Modelica. Proc. of the 1st Japanese Modelica Conference, Tokyo, Japan (139-144).
  6. Laughman, C.R., & Qiao, H. (2015). Mass conserving models of vapor compression cycles. Proc. of the 11th International Modelica Conference, Versailles, France.
  7. Jensen, J.M., & Tummescheit, H. (2002). Moving boundary models for dynamic simulations of two-phase flows. In Modelica 2002 Proceedings (235-244). Modelica Association.
  8. Pangborn, H., Alleyne, A., & Wu, N. (2015). A comparison between finite volume and switched moving boundary approaches for dynamic vapor compression system modeling. Int. J. Ref., 53, 101-114.
  9. Qiao, H., Laughman, C.R., Aute, V., & Radermacher, R. (2016). An advanced switching moving boundary heat exchanger model with pressure drop. Int. Journal Refrigeration, 65, 154-171.
  10. Zhang, W. J., & Zhang, C. L., (2006). A generalized moving-boundary model for transient simulation of dry- expansion evaporators under large disturbances. Int. J. Ref., 29, 1119-1127.

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