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Welcome to frads documentation

Date: 2024-02-26

Version: 1.2.5

frads project is an open source, BSD-licensed library providing easy-to-use wrapper for Radiance rendering engine.

Table Of Contents

The documentation consists of three parts:

  1. How-To Guides: Scenario-based how-to guides
  2. CLI Manual: Manual pages for all the command-line-interfaces.
  3. Reference: Code API documentation

Installation

You can find installation instructions on our README.

Project Overview

Frads is an open-source library providing high-level abstraction of Radiance matrix-based simulation workflows.

Frads automates setup of these simulations by providing end users with an open-source, high-level abstraction of the Radiance command-line workflow (Unix toolbox model), helping to reduce the steep learning curve and associated user errors. frads also provides the necessary infrastructure needed for seamless integration of Radiance and other modeling tools, such as EnergyPlus.

Intended audience

  1. Developers who are interested in incorporating multi-phase matrix methods into their software and are seeking examples and guidance; i.e., LBNL-suggested default parameters and settings; and,
  2. Engineering firms, researchers, and students who are comfortable working in the command-line or Python scripting environment and tasked with a project that cannot be completed with existing tools.

Why matrix-based methods?

Matrix algebraic methods reduce the time needed to perform accurate, ray-tracing based, annual daylight simulations by several orders of magnitude.

Why frads?

A good deal of expertise is needed to set up the simulations properly to achieve the desired level of accuracy. frads provides users with tools (e.g., mrad) that automatically determine which matrix-based method to use then sets the associated simulation parameters, helping beginners learn the different matrix methods by observing the tools’ behavior. The user is still required to understand basic concepts underlying matrix-based simulation methods (see tutorials).

Matrix-based methods also enable accurate, ray-tracing generated, irradiance, illuminance, and luminance data to be available for run-time data exchange and co-simulations. frads provides users with tools that generate the appropriate Radiance-generated data then interfaces with the “actuator” EMS module in EnergyPlus or within the Spawn-of-EnergyPlus and Modelica co-simulation environment. This enables end users to evaluate the performance of buildings with manual- and automatically-controlled shading and daylighting systems or other site and building features that can change parametrically or on a time-step basis.

Acknowledgements

This work was supported by the Assistant Secretary for Energy Efficiency and Renewable Energy, Building Technologies Program, of the U.S. Department of Energy, under Contract No. DE-AC02-05CH11231.