24Fa-Microclimate-UMCF

A Grasshopper plugin for microclimate simulations

The plugin is based on the urbanMicroclimateFoam open-source solver based on OpenFOAM, developed by the Chair of Building Physics at ETH Zürich.

• Github repository: https://github.com/OpenFOAM-BuildingPhysics/urbanMicroclimateFoam
• Gitlab repository: https://gitlab.ethz.ch/openfoam-cbp/solvers/urbanmicroclimatefoam

Overview

UMCF (urbanMicroclimateFoam) is an open-source solver for coupled physical processes modeling urban microclimate based on OpenFOAM.

Key Features

🌊 CFD - Computational fluid dynamics model

• Solves turbulent, convective airflow
• Handles heat and moisture transport in the air subdomain

🏗️ HAM - Heat moisture transport model

• Manages absorption and transport
• Controls storage of heat and moisture in porous building materials

☀️ RAD - Radiation model

• Calculates net longwave and shortwave radiative heat fluxes
• Uses view factor approach

🌳 VEG - Vegetation model

• Solves heat balance for urban trees
• Handles green surfaces

Installation

Prerequisites

• bluecfd core 2020
• UMCF plugin from PackageManager
• CheckInstallation component

Step-by-Step Guide

1. Install blueCFD-Core
2. Download blueCFD-Core-2020-1-win64-setup.exe from bluecfd.github.io

3. This provides OpenFOAM 8

4. Install UMCF Plugin

5. In Rhinoceros, execute PackageManager command
6. Search for UMCF and click Install (View on RhinoPackages)
7. Optional: Check Include pre-releases for all versions
8. Restart Rhinoceros to complete installation

1. Verify Installation
2. Navigate to UMCF tab in Grasshopper ribbon
3. Find Check Installation under Meta subcategory
4. Set Check input to True
5. This verifies integrity of blueCDF-Core 2020 and urbanMicroclimateFoam files

Features & Workflow

1. Simulation Domain Configuration

• The simulation domain consists of three regions:
• air region
• solid region
• vegetation region

2. Air Region Setup

• Managed by UMCF.AirRegion class
• Determined by Box Domain Dimensions
• Includes Atmospheric Boundary Layer (ABL) condition:
• Wind Speed
• Height
• Wind Direction

3. Solid Region Setup

• Managed by UMCF.SolidRegion class
• Requires mesh geometry input
• Stores:
• region name
• material
• Optional thickness value
• mesh parameters
• building temperature

4. Vegetation Region Configuration

• Managed by UMCF.VegetationRegion
• Requirements:
• mesh geometry input
• Leaf Area Density (LAD)
• vegetation properties
• mesh parameters

5. Timing Parameters

• Uses EnergyPlus Weather file (.EPW)
• Requires:
• Start Day (365-day based)
• start time
• duration
• end time is calculated by adding the start time and duration

6. Simulation Settings

• Key parameters include:
• Number of CPUs (N)
• maxFluidIterations (F)
• Write Interval (W)
• Initial Solid Timestep Factor (I)
• minDeltaT (T)
• maxDeltaT (T)
• minFluidIteration (F)
• pcEqnForm (p)
• dampingThickness (d)
• alphaCoefU (U)
• alphaCoefT (T)

7. Case Generation

• Connect all configured components
• Set Write Case to True
• Outputs UMCF.UMCFCase which must be connected to the Case Run component

8. Simulation Execution

• Two-step process:
• Prepare simulation
  • Set Prepare Simulation or Prepare Simulation in Parallel to True
• Run simulation
  • Set Run Simulation or Run Simulation in Parallel to True

Note: Use consistent parallel settings for preparation and execution

9. Analysis & Visualization

• Uses probing component
• Samples field values at point locations
• Writes results to file using input fields
• Enables value analysis and visualization by running the probes function

Documentation

📚 Visit docs.eddy3d.com for detailed documentation (Work in Progress)

Presentation

Team