ApacheHVAC

• Detailed building-integrated, dynamic thermal modelling of HVAC systems
• Optimise HVAC operation and minimise energy consumption and carbon emissions – get the system right for the building, budget and environment
• Simulate typical & innovative HVAC systems with minimal effort
• Exceptionally well suited to modelling mixed-mode and building-integrated systems, including double skin facades and earth-tube thermal pre-conditioning
• HVAC system design, component sizing and control design

ApacheHVAC uses a flexible schematic component-based approach that enables you to quickly assemble HVAC plant and control systems.  You can build from scratch or from pre-defined autosizable systems.

The module is dynamically integrated with our thermal analysis tool ApacheSim.  This is vital in providing a building-integrated approach where the HVAC system and building are assessed as a whole; allowing all gains/losses, heat transfer and thermal mass in the building to be accounted for alongside system performance. 

Time steps down to 1 minute can be defined to capture detailed dynamics.  You also have the option of combining detailed and idealised HVAC plant models for different rooms in the same model.

System Prototypes & Sizing Navigator

This workflow Navigator guides users through loading prototype system profiles and data, selecting systems, inputting system parameters and schedules of operation, and autosizing system equipment and controls.  Systems can then be analyzed for minute-by-minute, hourly, daily and annual performance.  This tool makes it easy to compare system alternatives from the earliest stages of design. 

The Navigator accelerates system setup for comparison of system alternatives from the earliest stages of design.  It also incorporates Quality Assurance (QA); saving users valuable time, and promoting easy team collaboration and training.

Multiplexing Feature

This unique functionality adds an extra dimension to the capabilities and productivity available in ApacheHVAC.  It enables engineers to easily deal with assigning HVAC data to very large, complex system models.  Multiplexing layers and tabular editing functionality facilitates fast and accurate data population with editing at global or individual levels.

HVAC systems

Some examples of typical & innovative systems that can be modelled in ApacheHVAC include:

• VAV systems with state-of-the-art controls, air and water supply temperature resets, airside and waterside economizer/free cooling (WSE), demand-controlled ventilation (DCV), etc.
• Highly tailored system controls and configurations
• Dedicated outside air systems (DOAS) with fan-coils, active/passive chilled beams, etc.
• Air-source heat pumps, DX cooling, and unitary cooling (split systems)
• Indirect-direct evaporative cooling systems (IDDE), desiccant-based air conditioning, etc.
• Hybrid hydronic/air systems, radiant chilled/heated floors, ceilings, and panels
• Underfloor air distribution (UFAD), displacement ventilation (DV)
• Vented stack-effect double-skin facades, thermal labyrinths, and earth tubes
• Mixed-mode systems with integrated control of mechanical and natural ventilation
• Hollow-core slab systems

Some examples of particularly advanced systems which can be modelled in ApacheHVAC include:

• Cutting-edge low-energy HVAC equipment, such as Dedicated Outside Air System (DOAS) with indirect-evaporative cooling and desiccant wheel regenerated by DX condenser coil
• Nat vent plus CO₂-based demand-controlled mechanical ventilation, active chilled beams, and radiant heating and cooling panels

Prototype Systems Library

Pre-defined prototype systems require minimal user input and provide increased productivity.  With fully editable pre-defined configurations, controls and equipment they are a valuable starting place for building custom systems.

• Packaged terminal units
  • air-conditioning with DX cooling and hot-water boiler (PTAC)
  • heat pump with DX cooling and air-source heat pump (PTHP)
• Single-zone air-conditioning units (CV or VAV)
  • DX cooling; direct-fired gas furnace heating
  • DX cooling; air-source heat pump, electric-resist. backup
• Multi-zone VAV-reheat systems (can also run as CV)
  • DX cooling and hot-water coils/boiler(s)
  • DX cooling and parallel fan-powered (PFP) boxes with 2-stage electric re-heat
  • Water-cooled chiller(s), chilled-water coils, and hot-water coils/boiler(s)
  • Water-cooled chiller(s), chilled-water coils, PFP boxes with 2-stage electric re-heat
• Dedicated outside air system (DOAS) with a range of possible zone-level units
  • Hot- and chilled-water (4-pipe) fan-coil units
  • Active chilled beams and fin-tube convectors or radiators
  • Four-pipe active beam induction units for both heating and cooling
• Indirect-direct evaporative cooling VAV system, with HW reheat and CO₂-based DCV
  • Coupling of 2-stage IDDE cooling SAT midbands to space cooling set points
• Mixed-mode system: integrated control of mechanical and natural ventilation/cooling
  • Integration of setpoints in control profiles for fenestration openings and HVAC airflow in mixed-mode mechanical plus natural ventilation/cooling system
• Chilled and heated ceiling panels with DOAS
• Passive chilled beams with DOAS
• Dual-fan, dual-duct VAV with zone-level mixing
• Underfloor air distribution system
  • UFAD supply air plenum thermal zone
  • Separate occupied and stratified zones
  • Heat-pipe to deliver dry, moderately cool air
  • Underfloor series/parallel fan-powered boxes
  • De-stratification of space with heating airflow
  • Fixed or variable-volume diffusers
  • Leakage path to return

Input Data

• Air-handling component parameters: coil duties, fan characteristics etc
• Operation profiles
• Radiator characteristics
• Central plant part-load efficiencies
• Controller parameters:
  • Sensed and controlled variables
  • On-off or proportional
  • Fixed or variable set-points
  • Set-points linked to other simulation variables via ‘formula profiles’
• Boolean inputs from other controllers

Output Options

• Results displayed in Vista and VistaPro, along with the weather data used to drive the simulation
• A wide range of tables and graphs are produced for results analysis including monthly summaries, ranges or user-specified synopses
• System outputs at the component level, suitable for input to duct sizing and component selection and duct sizing software, include:
  • Air flow rates, temperatures and humidities
  • Air handling component loads
  • Component psychrometric processes
  • Room unit loads
  • Central plant loads
• System performance indicators
  • System energy broken down by component or fuel
  • Carbon emissions
  • Performance at each node in the airside HVAC network in terms of air dry-bulb and wet-bulb temperatures, mass flow, volume flow, moisture content, relative humidity, and CO2 concentration
• Room performance indicators include:
  • Room temperatures: air, mean radiant, dry resultant
  • Comfort indices: predicted mean Vote (PMV) and percentage of people Dissatisfied (PPD)
  • Room loads: heating, cooling, humidification, dehumidification
  • Load breakdowns: casual & solar gains, conduction and ventilation losses, plant inputs
  • Surface temperatures
  • Energy Consumption: Annual, Monthly, Hourly
• Multiple results can be displayed simultaneously or aggregated
• Results can be displayed in both metric or Imperial (US) units
• Results can be exported to other windows applications for use in reports, presentations and further analysis