This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Block-oriented Models for Transient HVAC Simulations
Technical Paper
2005-01-2002
ISSN: 0148-7191, e-ISSN: 2688-3627
Annotation ability available
Sector:
Language:
English
Abstract
An improved block-oriented simulation methodology of vehicle air conditioning systems has been developed, based on dynamic and thermodynamic formulations of automotive components.
The method applied considers any system as dynamic and the steady-state as a particular condition reached during transient states. Therefore it is necessary for every component of the system to define the dynamic laws, the dynamic constants and to impose the initial conditions.
A few examples of modeled components are described in order to show the consistency of the thermodynamic differential approach and input/output relations between subsystems. An alternative approach of experimental look-up tables with respect to the thermodynamic differential method has also been applied, whenever it was convenient in terms of calculation improvements.
The model, although mono-dimensional, is able to describe different non-stationary behaviors in typical HVAC (Heating, Ventilating, and Air-Conditioning) applications: warm-up, cool-down, transient thermodynamic effects in air ducts and more. The model is currently being used during pre-development and development phases to dimension HVAC systems.
This article is focused on describing warm-up models: a comparison between simulations and experimental data is shown for different cases, in order to underline the effects of different components and boundary conditions. The model abilities in predicting the system behavior and the methodology approach are discussed: model sensitivity with respect to different heating sources, air-blowers, heat-exchangers and additional heaters (PTC) are taken into account, while changing wind tunnel boundary conditions.
Recommended Content
Authors
Topic
Citation
Parrino, M., Mannoni, A., Bonisoli, E., and Sorli, M., "Block-oriented Models for Transient HVAC Simulations," SAE Technical Paper 2005-01-2002, 2005, https://doi.org/10.4271/2005-01-2002.Also In
SAE 2005 Transactions Journal of Passenger Cars: Mechanical Systems
Number: V114-6 ; Published: 2006-02-01
Number: V114-6 ; Published: 2006-02-01
References
- Parrino M., “The pseudodynamic and structural methods in the development of computer code for vehicle thermal system applications”, ATA Vehicle Comfort, 2nd International Conference, 1992, Bologna, Italy, Vol. 2, pp. 865-874.
- Kikutani K., Heffernan D., “Development of auto air-conditioner software using structured methods”, SAE, 24-28 February 1992, Detroit, MI, USA, paper 920213.
- The MathWorks, “Matlab® - The Language of Technical Computing, User's Guide Version 7”, 2004.
- The MathWorks, “Simulink® - Simulation and Model-Based Design, Using Simulink® Version 6”, 2004.
- Sorli M., Gastaldi L., Quaglia G., “Caepneum: A simulation tool on pneumatic elements and systems developed in Matlab”, Proc. 5th Scandinavian Conf. on Fluid Power SICFP'97, Linkoping, Sweden, 28-30 May 1997, Vol. 2, pp. 319-334.
- Sorli M., Figliolini G., Pastorelli S., “Dynamic Model and Experimental Investigation of a Pneumatic Proportional Valve”, IEEE/ASME Transactions on Mechatronics, Vol. 9, No. 1, March 2004.
- ASHRAE Fundamentals Handbook, 1997.
- http://www.dupont.com/suva/emea/products/technical/thermoprop.html
- Sorli M., Franco W., “Gas line pulse analysis”, 6th Triennal Int. Symp. on Fluid Control, Measurement and Visualization (ISBN 2-7622-0126-8), FLUCOME 2000, 13-17 August 2000, Sherbrooke (Qc), Canada.
- Monforte R., “Identification of the numerical model for an automotive application thermostatic expansion valve”, 5th SAE Vehicle Thermal Management Systems, 14-17 May 2001, Nashville, TN, USA, 2001-01-1700.
- Monforte R., “An improved numerical model for thermostatic expansion valves used in automotive air-conditioning systems”, 6th SAE Vehicle Thermal Management Systems, 18-21 May 2003, Brighton, UK, 2003-01-0739.
- Hendricks T. J., “Optimization of vehicle air conditioning systems using transient air conditioning performance analysis”, SAE Vehicle Thermal Management Systems, 14-17 May 2001, Nashville, TN, USA, p-363, 2001-01-1734.