Individual Components

Recently, we have found ourselves asked to write single, quite complex TRNSYS components for clients and to build them into somewhat conventional systems; technology assessment tools if you will. In some cases, the client has been willing for us to share the components with the larger public. Somewhat inappropriate for inclusion in one of the TESS Libraries, we have chosen to offer these components for sale individually instead.

Premiere Components: Detailed Models with Full Documentation

Icon Name Type Number Description Cost Source Code DLL Proformas Technical Doc Example Sample Catalog Data

Dry Fluid Cooler 511 This component models a dry fluid cooler; a device used to cool a liquid stream by blowing cool air across the coils. The user provides the performance at design conditions (easily found on the internet) and the model calculates the off-design performance. The manual for this model includes a detailed engineering description of how the off-design performance is calculated. $US 150

Solar Collector 539 We’re really excited about this new solar collector and hope that it will replace the Type 1 collector in standard TRNSYS. The models takes the results from a collector efficiency test and calculates the collector loss coefficient and the transmittance-absorptance product at normal incidence by first solving for the collector heat removal factor (FR). The collector is divided into a series of isothermal temperatures nodes and the model accounts for the capacitance of the collector and fluid! This eliminates many of the annoying controller oscillations that plague simulations using the Type 1 collector. The model allows the user to connect collectors in series without having to string them together in the studio. The model also allows the user to control the flow rate through the collector in order to maintain the outlet temperature at a user-defined set point. $US 200

Noded Pipe 604 Unlike the standard Type 31 pipe model in TRNSYS, this component considers the impact of the pipe mass, and insulation mass. The model calculates the heat loss coefficient based on the fluid properties, the pipe properties, the insulation properties, and convection (forced and natural) and radiation from the outer surface to the environment. The model assumes that the pipe can be characterized by a series of inter-connected, fully-mixed, fluid nodes (mimics plug-flow when the number of nodes is high). Unlike any other pipe model that we know of in TRNSYS, this model allows you to flow fluid through either direction in the pipe (just not both directions in the same time step). $US 150

Air Duct 607 Long missing from the standard TRNSYS library, this component allows the user to estimate the heat losses/gains by an air stream as it moves through a duct (circular or non-circular ducts can be modeled). The model assumes that the duct can be characterized by a series of inter-connected, fully-mixed, air nodes. Pressure drop effects are not calculated. The duct may be insulated and both forced convection and free convection (natural convection) effects are considered. $US 100

Horizontal Ground Heat Exchanger 916 This component models the heat transfer to/from the ground from a series of horizontal pipes buried in the earth. The pipes may be configured in any conceivable flow configuration including all in parallel, serpentine, double-serpentine, intertwined quadruple serpentine, etc. Insulation may be placed on the soil surface and also down the edges of the pipe system. Pipe-to-pipe interaction is considered. The pipes are surrounded by a fully 3-D rectangular conduction model of the ground that includes the impact of energy storage in the ground. $US 200

Slab on Grade 934 This component interacts with zone models to calculate the heat transfer from the zone to the soil through an insulated (or not) slab. The soil beneath the slab is a fully 3-D rectangular soil conduction model. Near and far field considerations are taken into account. The bottom of the slab and the edges of the footing may be insulated. A portion of the upper slab surface may also be covered with an insulating material (carpet etc.). This model is based on the TESS slab model approach which has been recognized as a research standard by IEA task 34/43 and validated against a detailed analytical solution. You may also be interested in a version of this program that interacts with the detailed multi-zone building model in TRNSYS (Type 56).
$US 250

Heat Pump Water Heater 938 A heat pump water heats an entering liquid stream by removing energy from an air stream passing across the evaporator coil of the device. In this model, the performance of the device is read from normalized external data files as a function of the entering liquid temperature, entering air temperature and entering air relative humidity. The model calculates all of the component energy flows (evaporator, condenser, compressor, blower) in the device and reports them each time step.
$US 100

Tankless Water Heater 940 This component models a tankless water heater; a device used to heat a liquid stream by the addition of heat from either an electric heating element or a gas combustion heating source. In simple terms it is an auxiliary heater with internal controls to modulate the heat input to the fluid. One of the important features of tankless water heaters is their quick response to changing conditions. To study systems with quick response, small timesteps are typically used in TRNSYS. However, small timesteps substantially increase the simulation speed and running at timesteps approaching one second may not be feasible for annual simulations. Unfortunately large timesteps (15 minutes or greater) may cause severe over or under-heating of the fluid, as control decisions are then only made once each timestep. To alleviate this problem, the model utilizes an internal control methodology that allows multiple control decisions to be made within a single timestep, possibly turning on and off the heating many times within a single timestep. The duration of each of these sub-timesteps is then recorded (along with the temperatures during each period) and the model reports the average conditions over the timestep (the standard TRNSYS output convention). The model also considers the effects from minimum flow rates for operation, stepped heating capacity, time-delays, temperature deadbands, minimum input fractions, and stand-by effects. NREL has adopted this model for their analysis of DHW systems for the Building America program. $US 200
Buried Pipe Wrapper for Renctangular Parallelepiped Tanks 943 This component interacts with the TESS storage tank model and provides a fully 3-D conduction soil wrapper for the fluid-filled tank. Near and far field considerations are taken into account. This model is based on the TESS slab model approach which has been recognized as a research standard by IEA task 34/43. A version of this component where there is a structure (house etc.) above the tank is also available. $US 175
Exposed Twin-Conductor Pipe 950 This component models the two pipes in a sheath piping system common to the geothermal heat pump and district heating industries (Ecoflex TM). In this model, two pipes are encapsulated by an insulating material and then surrounded by a cylindrical sheath. The model allows the user to specify whether the pipes are flowing in the same direction or opposite directions. Pipe-to-pipe interaction is considered. The heat losses via convection to the ambient air and radiation to the surroundings are calculated by the model. $US 150
Buried Twin-Conductor Pipe 951 This component models the two pipes in a sheath piping system common to the geothermal heat pump and district heating industries (Ecoflex TM). In this model, two pipes are encapsulated by an insulating material and then surrounded by a cylindrical sheath. The model allows the user to specify whether the pipes are flowing in the same direction or opposite directions. Pipe-to-pipe interaction is considered. The cylindrical sheath (outer pipe) is surrounded by a fully 3-D radial conduction model of the ground that includes the impact of energy storage in the ground. $US 200
Evacuated Tube Solar Collector 965 This component is nearly identical to the new Type 539 solar collector model, but utilizes bi-axial incidence angle modifiers to allow optically non-symmetric collectors to be studied. $US 200

Premiere Budget Components: Select Any Two Components for $US 150

Icon Name Type Number Description Cost Source Code DLL Proformas Technical Doc Example Sample Catalog Data

Performance Map Cooling Coil 697 In many cases, a user wishes to utilize a cooling coil in a simulation for which detailed performance data is available (usually from a manufacturer’s web site). This component utilizes external data files that provide the normalized capacity (both total and sensible) as a function of the entering air dry bulb temperature, entering air wet-bulb temperature, the air flow rate, the entering water temperature and the entering water flow rate. 2 / $US 150



Printegrator 933 Finally someone wrote a component that combines the Type 24 integrator and the Type 25 printer into one model. The user has the option of specifying the integration interval (and therefore the printing interval) including monthly summaries, providing detailed descriptions via Labels, specifying units of the variables (instead of initial values), and skipping the integration on selected variables (and just printing the instantaneous value). We use this component in all of our simulation and it saves a lot of time! The output from this model is directly importable into Microsoft Excel and other spreadsheet applications. 2 / $US 150



Air Conditioner 964 Using the approach popularized by the DOE-2 simulation program, the performance of an air conditioner can be characterized by bi-quadratic curve fits. In this model, normalized multipliers for the total cooling capacity, the sensible cooling capacity, the energy input ratio, and the coil bypass fraction are calculated based on the coil entering air conditions and the ambient temperature. The capacity is assumed to ramp up exponentially to its steady state value based on a user-specified time constant. 2 / $US 150



Air Source Heat Pump 966 Using the approach popularized by the DOE-2 simulation program, the performance of an electric air-source heat pump can be characterized by bi-quadratic curve fits. In this model, normalized multipliers for the total cooling capacity, the sensible cooling capacity, the cooling power, the total heating capacity, the heating power, and the coil bypass fraction are calculated based on the coil entering air conditions and the ambient temperature. The capacity is assumed to ramp up exponentially to its steady state value based on a user-specified time constant. 2 / $US 150



Forced-Air Furnace 967 In this model, the performance of a forced-air furnace is characterized by a constant heat input ratio. The heating capacity is assumed to ramp up exponentially to its steady state value based on a user-specified time constant. 2 / $US 150



Running Total and Averages 939 This component calculates the running totals (integrated) and running averages over a running user-specified time range. For example, this program could calculate the average temperature over the last 24 hours or the water heater gas consumption over the last 4 hours. 2 / $US 150