Steady-state modeling platform is becoming a more and more important tool to aid engineers to design and optimize vapor compression system, perform HVAC equipment design (select compressor, heat exchanger, EXV, etc. based on system requirements) and can also help marketing people to do a selection of components and system for customers.
The modeling platform for dynamic/transient vapor compression system is also attractive to engineers for developing control algorithms by integrating dynamic model into control system (MIL) and software system (SIL).
However, utilizing two separate simulation modeling platforms to perform steady state and transient simulations presents a large challenge of big burdens of increased software development and maintenance effort, and possible inconsistency in the predicted results.
Therefore, in order to provide more efficient and accurate results, a combination of these two methods would need to be used. In response to this need, DSIMAC was developed.
DSIMAC is a modeling platform that seamlessly combines steady-state and dynamic modeling together by using modern objective programming language C++. It serves the industrial needs of an integrated steady state and transient vapor compressor simulation tool. In the aspect of static simulation, it aid engineers to select HVAC equipment components according to system requirements and optimization analysis. In other aspect of dynamic simulation, one can develop control algorithms by integrating dynamic model from DSIMAC into control system (MIL) and software system (SIL).
Introduction of Simulation Platform for HVACR
DSIMAC modeling platform consist of a high efficient modeling architecture which has three separate independent sections: modeling GUI, key calculation engine and table-based analysis framework. Since all those three sections are programmed by using objective C++, the key calculation engine which is like dll (dynamic link library) can be easily integrated into marketing selection software (steady state), bulding energy analsysis tool (steady state),and embedded software HVAC C++ (SIL,HIL) or simulink control HVACR (MIL).
Architecture 1 of Simulation Platform for Vapor Compression System
Architecture 2 of Simulation Platform for Vapor Compression System
With increasing emphasis being placed on energy efficiency, the enhancement of vapor compression system performance is receiving much attention due to their high level of energy intensity.
DSIMAC simulation platform serves the needs. One can utilize the tool to build any kind of system model of air conditioning quipments and integrate it with conditioned space. Analysis with variable ambient temperature, part load, and etc. can be easily performed with the tool.
Example: steay state simulation of air conditioning unit with variable speed compressor and EXV
Simulation of transient or dynamic system of air conditioning/refrigeration equipment is becoming more and more attractive because it can be used to design and evaluate a system, to understand the dynamic behaviour of a system, and more importantly to help design control algorithm of such a system.
Our simulation platform DSIMAC integrates steady state modeling capability of thermodynamic physical systems together with transient modeling capability of such systems, can at most serve the needs of MBD (model-based-design), such as MIL (model-in-loop), SIL (software-in-loop) and HIL (hardware-in-loop) for the development of control algorithms in the field of HVAC systems.
Example: dynamic simulation of air conditioning unit with PI control of superheat
Dynamic simulation result of air conditioning unit with PI control of superheat
In the simulation platform, there are 7 different compressor blocks and each block has three models (cycle, ARI fitting and physical fitting). The 7 compressor blocks are: single speed, variable speed, variable speed & volume ratio, single speed with economized port, variable speed with economized port, variable speed centrifugal with IGV, variable speed centrifugal with IGV and economized port.
Blocks for heat exchanges in the platform, include RTPF,MCHX, BPHX, tranditional shell tube, flooded shell tube, and falling film evaporator. Capillary, TEV, EEV, ball valve, flash tank, receiver, accumulator, etc. are modeled in the platform.
Compressor blocks in simulation platform
Heat exchanger blocks in simulation platform
Valves & Regulating devices in simulation platform