Relationship between steam pressure and temperature

EXPERIMENT-1 Pressure-Temperature Relationship for Steam OBJECT | Madushan Sandaru -

relationship between steam pressure and temperature

Download Citation on ResearchGate | The Relation Between Pressure, Temperature and Specific Volume of Steam at Elevated Temperatures and Pressures. Basically temperature and pressure are directly proportional to each other. Increase of an one quantity will lead to the increase of the other. but. The heat quantities and temperature/ pressure relationships referred to in this. Handbook are taken from the Properties of Saturated Steam table. Definitions of.

T-S diagram of the separating and throttling calorimeter.

relationship between steam pressure and temperature

Start the boiler and supply steam to the separating and throttling calorimeter unit. Start the cooling water flow through the condenser. Open steam valve and allow the steam to flow through the calorimeters to warm through the steam. Open the throttle valve and adjust to give a pressure at exhaust of about 5cm Hg measured on the manometer.

Drain the separating calorimeter.

Pressure - temperature relation for saturated steam - Tubes International

Start the test and take readings at minutes intervals. When a reasonable quantity of condensate is collected measure the quantity of separated water and the quantity of condensate. Using the average values, obtain the specific enthalpy of steam at state C hence calculate the dryness fraction of incoming steam.

Also calculate the specific enthalpy of incoming steam. With the compressor running and using the Dobbie McInnes indicator, mark the atmospheric pressure line on the indicator card.

Produce a P-V indicator diagram by opening the pressure valve to the indicator and operating the indicator marker in the usual manner. In the article Principal Applications for Steamwe discussed several applications in which steam is used.

In the sections that follow, we will discuss the types of steam used in these applications. Saturated dry steam results when water is heated to the boiling point sensible heating and then vaporized with additional heat latent heating. If this steam is then further heated above the saturation point, it becomes superheated steam sensible heating. Saturated Steam Dry As indicated by the black line in the above graph, saturated steam occurs at temperatures and pressures where steam gas and water liquid can coexist.

In other words, it occurs when the rate of water vaporization is equal to the rate of condensation.

Calculator: Saturated Steam Table by Pressure | TLV - A Steam Specialist Company (International)

Some of these are: Property Rapid, even heating through latent heat transfer Improved product quality and productivity Pressure can control temperature Temperature can be quickly and precisely established High heat transfer coefficient Smaller required heat transfer surface area, enabling reduced initial equipment outlay Originates from water Safe, clean, and low-cost Tips Having said this, it is necessary to be mindful of the following when heating with saturated steam: Heating efficiency may be diminished if steam other than dry steam is used for process heating.

The continued addition of heat causes the vibration to increase to such an extent that some molecules will eventually break away from their neighbours, and the solid starts to melt to a liquid state. However, it has been shown that the melting point of ice falls by 0. Heat that breaks the lattice bonds to produce the phase change while not increasing the temperature of the ice, is referred to as enthalpy of melting or heat of fusion.

This phase change phenomenon is reversible when freezing occurs with the same amount of heat being released back to the surroundings.

relationship between steam pressure and temperature

For most substances, the density decreases as it changes from the solid to the liquid phase. However, H2O is an exception to this rule as its density increases upon melting, which is why ice floats on water. Water In the liquid phase, the molecules are free to move, but are still less than one molecular diameter apart due to mutual attraction, and collisions occur frequently.

relationship between steam pressure and temperature

More heat increases molecular agitation and collision, raising the temperature of the liquid up to its boiling temperature. The enthalpy of all other states can then be identified, relative to this easily accessible reference state.

Properties of Steam

Sensible heat was the term once used, because the heat added to the water produced a change in temperature. However, the accepted terms these days are liquid enthalpy or enthalpy of water. It is from these figures that the value for the specific heat capacity of water Cp of 4. Steam As the temperature increases and the water approaches its boiling condition, some molecules attain enough kinetic energy to reach velocities that allow them to momentarily escape from the liquid into the space above the surface, before falling back into the liquid.

Further heating causes greater excitation and the number of molecules with enough energy to leave the liquid increases. As the water is heated to its boiling point, bubbles of steam form within it and rise to break through the surface.

  • Calculator: Saturated Steam Table by Pressure
  • Types of Steam

Considering the molecular arrangement of liquids and vapours, it is logical that the density of steam is much less than that of water, because the steam molecules are further apart from one another. The space immediately above the water surface thus becomes filled with less dense steam molecules.

relationship between steam pressure and temperature

When the number of molecules leaving the liquid surface is more than those re-entering, the water freely evaporates. At this point it has reached boiling point or its saturation temperature, as it is saturated with heat energy.