How do you find the specific heat of moist air?

Specific enthalpy of moist air can be expressed as:

1. h = ha + x hw (1) where. h = specific enthalpy of moist air (kJ/kg, Btu/lb)
2. ha = cpa t (2) where.
3. h = cpa t + xs [cpw t + hwe] + (x – xs) cw t (7) where.
4. h = cpa t + xs [cpw t + hwe] + (x – xs) ci t – (x – xs) him (8) where.

How do you calculate specific volume of moist air?

W = humidity ratio of saturated air, mass of water vapor per mass of dry air. Vo = specific volume of dry air under 14.696 psia (101.325 kPa) pressure, ft/Ibm (m°/kga). Vo = volume of saturated air, ftp/lbm dry air (m3/kg dry air). Vas = V5 – Va, ft/Ibm dry air (mⓇ/kg dry air).

How do you calculate CP and CV for air?

The nominal values used for air at 300 K are CP = 1.00 kJ/kg. K, Cv = 0.718 kJ/kg. K,, and k = 1.4.

What is specific heat of dry air?

1.005 kJ/kgK
The average specific heat of dry air at one atmospheric temperature is cpa=1.005 kJ/kgK. The specific heat of water vapour is cpw=1.88 kJ/kgK.

Which is heavier dry air or moist air?

Dry air consists mostly of nitrogen and oxygen molecules, which weigh more than water molecules. Therefore, moist air is lighter than dry air if both are at the same temperature and pressure.

What is specific volume measured in?

cubic meters
Specific volume is a property of materials, defined as the number of cubic meters occupied by one kilogram of a particular substance. The standard unit is the meter cubed per kilogram (m3/kg or m3·kg−1).

Is moist air hot or cold?

In humid air, sweat evaporates from your skin more slowly, which makes you feel hotter. In cold air, of course, sweating isn’t usually an issue. Instead, the usual explanation is that damp air transfers heat more quickly than dry air, allowing more heat to escape from your body and making you feel colder.

How to calculate dry air specific heat capacity?

1. Introduction 2. Humid air specific heat capacity calculation 3. Dry air specific heat capacity 4. Dry air isentropic ratio 1. Introduction The absolute humidity is calculated from the specific heat of dry air and the specific heat of water ponderated by the absolute humidity. 2. Humid air specific heat capacity calculation

How to calculate enthalpy of moist air at 25oC?

The enthalpy of humid air at 25oC with specific moisture content x = 0.0203 kg/kg (saturation), can be calculated as: Note! – the latent heat due to evaporation of water is the major part of the enthalpy. The sensible heat due to heating evaporated water vapor can be almost neglected.

How do you calculate the properties of air?

Here is a little calculator for calculating the properties of air. Enter the pressure (Pa) and Temperature (K), and the calculator should produce an estimate for the specific heat capacities, thermal conductivity, and density.

Which is the correct value for air specific heat?

For ordinary calculations – a value of specific heat cp = 1.0 kJ/kg K (equal to kJ/kg o C) or 0.24 Btu (IT)/lb °F – is normally accurate enough For higher accuracy – a value of Cp = 1.006 kJ/kg K (equal to kJ/kg o C) or 0.2403 Btu (IT)/lb °F – is better Online Air Specific Heat Calculator