ACSIM

ACSIM is a simulation tool for single-stage air conditioning systems comprising a compressor, finned-tube evaporator and condenser, thermostatic and electronic expansion valves, and interconnecting tubing. The program incorporates evaporator and condenser models from EVAP-COND, a stand-alone simulation tool developed by NIST for air-to-refrigerant heat exchangers ( https://www.nist.gov/services-resources/software/evap-cond-version-50). Since ACSIM is fully compatible with EVAP-COND, users can evaluate how heat exchangers designed and optimized in EVAP-COND affect overall system performance. ACSIM uses refrigerant thermophysical properties based on the NIST Standard Reference Data 23; NIST Reference Fluid Thermodynamic and Transport Properties Database (REFPROP): Version 10.0 (https://www.nist.gov/srd/refprop). ACSIM can carry out simulations using refrigerant blends with up to six components.

ACSIM Installation Instructions

1. Download the file ACSIM_1.0_Setup.zip.
2. Extract all files to a folder of your choice
3. Double-click setup.exe to launch the installation wizard. Follow the prompts.

The installation module will:

• Install the ACSIM graphical interface, Help Menu, and Instruction Pages. (It is recommended that you accept the default location.)
• Install the simulator AC.exe and related read/write files in C:> …> Documents >NIST>ACSIM
• Create an ACSIM startup group accessible from the Start button.
• Create an ACSIM shortcut and place an icon on the desktop.
• Create a shortcut for the Instruction Pages from the Start button.

Following ACSIM installation, the user needs to manually load REFPROP fluid files to a designated ACSIM ‘fluids’ folder (refer to the Instruction Pages, page 6).

Similar to EVAP-COND, ACSIM uses refrigerant property look-up tables to facilitate fast simulations. The ACSIM installation package includes look-up tables for the following refrigerants and refrigerant blends: ammonia, isobutane, propane, R22, R32, R134a, R152a, R161, R404A, R407C, R410A, R444A, R446A, R447A, R450A, R452B, R454B, R460A, R507A, R513A, R515B, and R1234yf. Additional refrigerant tables can be generated using TableGen2, a utility based on REFPROP v10.0. Note that ACSIM ‘fluids’ folder must include fluid files for all blend’s components.

TableGen2 Installation Instructions

Download the file TableGen2.zip and extract all files to a user-accessible folder.
Read and follow the instructions provided in TableGen2_Info.pdf.

ACSIM may require manual changing of the display resolution from the PC default setting if a displayed schematic of refrigerant circuitry is different than the schematic shown on the screen capture below. In such a case, changing the resolution to 1360x768 typically corrects the problem. Starting with the Start button, select Setting>Display>Display resolution>New value.

Upon installation, follow the tutorial in the Instruction Pages or Help Menu to familiarize yourself with ACSIM features.