Air Wind Flow Through Opening Calculator

Aspects of wind that affect the ventilation rate include average speed, prevailing direction, seasonal and daily variation in speed and direction, terrain, and local obstructions such as nearby buildings, hills, trees, and shrubbery.

Wind Flow Through Opening Calculator

Aspects of wind that affect the ventilation rate include average speed, prevailing direction, seasonal and daily variation in speed and direction, terrain, and local obstructions such as nearby buildings, hills, trees, and shrubbery.

Humidification Humidifier Load Calculations and Calculator

When calculating energy requirements for a humidification system, the effect of dry air on any material supplying it with moisture should be considered. The release of liquid in a hygroscopic material to a vapor state is an evaporative process that requires energy.

Elastic Compression Bandage LaPlace's Law

LaPlace's law states that within a tubular structure the change in pressure required to cause distension is proportional to the surface wall tension and inversely proportional to its radius. In other words, a structure with a larger radius and low surface tension requires minimal change in pressure to cause further dilatation however one with a smaller radius and high surface tension requires a significant amount of pressure.

Temperature Rise Across Fan Calculator

In certain applications, it may be desirable to calculate the temperature rise across the fan application. For low pressure rises (< 10 in. of water), the temperature rise may be estimated by the following:

Hydraulic Diameter of Rectangular Ducts Calculator

Hydraulic Diameter of Rectangular and Non-Circular Ducts Calculator. The characteristic length for internal flow in pipes and tubes is the inside diameter.

Thermal Conductivity Rocks and Soil

Typical Apparent Thermal Conductivity Values for Soils and Rocks

Condensation Resistance Factor Calculator

Glass or Frame Condensation Resistance Factor (CRF) or Temperature Index (I). Current measures of condensation resistance of a fenestration system are the condensation resistance (CR) as defined by NFRC500 (2014j) and its user guide (2014h), the condensation resistance factor (CRF) as defined by AAMA (1988), or the temperature index (I), as defined in CSA Standards A440 and A440.1.

Minimum Ventilation Rates in Rooms

Minimum Ventilation Rates in the Breathing Zone, Based on ANSI/ASHRAE Standard 62.1-2007

Steady State Fenestration Heat Energy Flow and Loss

Energy flows through fenestration via (1) conductive and convective heat transfer caused by the temperature difference between outdoor and indoor air; (2) net long-wave (above 2500 nm) radiative exchange between the fenestration and its surroundings and between glazing layers;

Freezing Point and Properties of Foods

The following is the Unfrozen Composition Data, Initial Freezing Point, and Specific Heats of Food items

Temperature and Altitude Corrections for Air

The temperature and barometric pressure of atmospheric air vary considerably with altitude as well as with local geographic and weather conditions.

Effects of Discharge Rate and Temperature on Battery Capacity and Life

The rate at which a battery is discharged and its operating temperature have a profound effect on its capacity and life.

Relative Humidity and Weight per Cubic Foot Volume of Air

The density and moisture weight can be estimated with the following table - determine the temperature then the known relative humidity to determine the density of water moisture and weight per cubic ft

Heat Gain from Lighting Calculator

The energy emitted by lighting and then absorbed by the structure and contents contributes to space cooling load only after a time lag, some still reradiating after the heat sources have been switched off.

Latent Energy Load Moisture Removal or Addition Calculator

HVAC air exchange modifies the moisture content of air in a building. The rate of energy consumption associated with these latent loads, to add or remove water is...

Wind Chill Calculator and Equations

Wind-chill or wind chill, (popularly wind chill factor) is the perceived decrease in air temperature felt by the body on exposed skin due to the flow of air.

Building Sensible Heat Thermal Load with Air Exchange Calculator

Air exchange increases a building’s thermal load in several ways. First, incoming air must be heated or cooled from the outdoor air temperature to the indoor or supply air temperature. The rate of energy consumption by this sensible heating

Radiative Heat Transfer Coefficient of a Human Calculator

The linearized radiative heat transfer coefficient can be calculated with, average emissivity of clothing or body surface, Stefan-Boltzmann constant, effective radiation area of body, Activity metabolic rates

Metabolic Rate Energy Burned Calculator

When metabolic rates must be determined more accurately than is possible with tabulated data, physiological measurements with human subjects may be necessary. The rate of metabolic heat produced by the body is most accurately measured by the rate of respiratory oxygen consumption and carbon dioxide production.