q = measured air flow (ft 3 /min)
Δx = difference in humidity ratio (lb h2o /lb dry_air )
The latent heat flow due to moisture in air can be expressed in SI-units (metric) as
Q l = h we ρ q Δx / 3600 (2)
Q l = latent heat flow (kW)
h we = latent heat of vaporization of water ( 2454 kJ/kg - in air at atmospheric pressure and 20 o C)
ρ = air density at standard conditions ( 1.202* kg/m 3 )
q = air flow (m 3 /hr)
Δx = difference in humidity ratio ( kg h2o /kg dry_air )
*Note that properties of air changes with temperature. Interpolate values if necessary.
A ventilation system transports 10000 m 3 /h of air through a building.
The state of the make-up (supply) air is 0 o C and 100% relative humidity. From the Mollier diagram the humidity ratio - x - can be estimated to 0.0037 ( kg h2o /kg dry_air ) .
The state of the room air is 20 o C and 40% relative humidity. From the Mollier diagram the humidity ratio can be estimated to 0.0057 ( kg h2o /kg dry_air ) .
The latent heat flow can be calculated as
Q l = (2465.56 kJ/kg) (1.202 kg/m 3 ) (10000 m 3 /h) (( 0.0057 (kg h2o /kg dry_air ) ) - ( 0.0037 ( kg h2o /kg dry_air ) )) / 3600
= 16.5 kW
Moist and humid air - psychrometric charts, Mollier diagrams, air-condition temperatures and absolute and relative humidity and moisture content.
Online calculator, figures and tables showing density, specific weight and thermal expansion coefficients of air at temperatures ranging -100 to 1600 °C (-140 to 2900 °F) at atmospheric and higher pressure - Imperial and SI Units.
The mass of water vapor present in moist air - to the mass of dry air.
Air heating buildings - heat supply vs. air flow and temperature.
Latent and sensible cooling and heating equations - imperial units.
Latent and sensible cooling loads to consider when designing HVAC systems.
The Great Sensible Heat Factor is the ratio sensible to total heat in a cooling coil.
Classification of heat recovery efficiencies - temperature efficiency, moisture efficiency and enthalpy efficiency - online heat exchanger efficiency calculator.
Enthalpy change and temperature rise when heating humid air without adding moisture.
Latent heat of vaporization for fluids like alcohol, ether, nitrogen, water and more.
Melting and boiling point temperatures, latent heat of evaporation, and melting heat of common substances like copper, gold, lead and more - SI units.
Sensible and latent heat of moist air.
Latent heat with vaporized propane.
Calculating heat removed with air by measuring the wet bulb temperature.
Room Sensible Heat Factor - RSHF - is defined as the sensible heat load divided by the total heat load in a room
Steam table with sensible, latent and total heat, and specific volume at different gauge pressures and temperatures.
Saturated Steam Table with properties like boiling point, specific volume, density, specific enthalpy, specific heat and latent heat of vaporization.
Sensible heat is dry heat causing change in temperature but not in moisture content
The ratio Sensible Heat (or Cooling) Load to the Total Heat (or Cooling) Load.
Vapor and steam enthalpy, specific enthalpy of saturated liquid, saturated vapor and superheated vapor.
Thermal properties of water at different temperatures like density, freezing temperature, boiling temperature, latent heat of melting, latent heat of evaporation, critical temperature and more.
Add standard and customized parametric components - like flange beams, lumbers, piping, stairs and more - to your Sketchup model with the Engineering ToolBox - SketchUp Extension - enabled for use with the amazing, fun and free SketchUp Make and SketchUp Pro . Add the Engineering ToolBox extension to your SketchUp from the Sketchup Extension Warehouse!
We don't collect information from our users. Only emails and answers are saved in our archive. Cookies are only used in the browser to improve user experience.
Some of our calculators and applications let you save application data to your local computer. These applications will - due to browser restrictions - send data between your browser and our server. We don't save this data.