Tools for design of solar systems using air as the heat transfer media.
Tools for sizing ducts and fans.
Pipe flow pressure drop calculator.
|Pump and Plumbing Sizing for Solar Water/Space Heating Systems|
|Pump and Plumbing Sizing for Solar Water or Space Heating System||This page covers the details of sizing the pump and the plumbing for a solar space or water heating system so that the system efficiently transfers heat from the collector to the storage tank without being excessively large.|
|How to Determine Collector Flow Rates||This page takes you through how to determine flow rate for your collector, and what the tradeoffs are ...|
set of calculators for pressure drop, airflow calculations, ...
|Free Calc -- a variety of HVAC
nicely done and generally easy to use calculators for water pipe and air
duct pressure losses, channel flow, fan laws, ...
|Air Duct Friction Loss Calculator
From The Engineering Toolbox
|A simple calculator for calculating the pressure losses in air ducts. Useful for sizing ducts and fans.|
|Air Friction chart for flex ducts
|An easy to use chart to look up
friction losses for flex ducts.
I find this one simple chart answers most of my duct loss questions -- it even has a correction for bends at the bottom.
|Flex Duct Loses Due to Compression
Static Pressure Losses in
6”, 8”, and 10” Non-Metallic Flexible Duct...
|Flex ducting is subject to extra
losses compared to rigid metal ducts when it has sags between supports and
when it is not fully stretched out. These extra losses can be
This paper measures extra losses for flex ducting with sags and with compressed ducts.
Stack Effect Ventilation Calculator
|Estimates airflow for thermal stacks|
|Friction loss in round or
Note: The Engineering Toolbox site has a lot of useful stuff, but also has some very scummy popup windows -- so beware.
|A very simple air duct pressure
The duct calculator at the link just above is will handle a wider variety of conditions, but is more complex to use.
|Air Density Calculator
|Calculates air density for the
temperature and altitude you input.
nice and flexible calculator for Reynodls number -- accepts a wide variety
of units and flow conditions.
The fluid viscosity inputs that are needed can be looked up on the Engineering Toolbox website.
|Borst Engineering and Construction
|Borst Engineering has a whole raft of calculators -- HVAC, solar position, shading, and incident heat, water wheels, pipe sizing, ...|
|Copper Pipe Pressure Drop
|Handy pressure drop table for
Note: 1 psi = 2.3 ft of head
Other pressure drop tools on this site:
|Pipe Pressure Drop Online
online pressure drop calculator. Handles a wide variety of situations.
Also figures loss for bends, orifices, nozzles, ...
|Pipe flow and Duct Flow Calculators
|Calculators for pressure loss in pipes and ducts, steam tables, and a Psychrometric Calculator|
|Hydronic Heaters -- Baseboard, ...|
|SlantFin Hydronic Baseboard Radiator Output||SlantFin manual on their hydronic baseboard units showing output at lower temps that might be typical of what you would get on efficient solar heating systems.|