In psychrometric chart horizontal lines indicate?Asked by: Kaia Fisher PhD
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Likewise, people ask, What do the vertical and horizontal lines on a psychrometric chart represent?
Dry-bulb temperature is located on the horizontal, or x-axis, of the psychrometric chart and lines of constant temperature are represented by vertical chart lines. Since this temperature is so commonly used, assume that temperatures are dry-bulb temperatures unless otherwise designated.
Simply so, What is represented by a horizontal line but non-uniformly spaced on the psychrometric chart?. What is represented by horizontal lines but non-uniformly spaced on the psychrometric chart? ... The inclined lines from the saturation curve and parallel to the wet-bulb temperature lines denote Enthalpy.
Additionally, What is psychrometric chart used for?
Psychrometric charts are complex graphs that can be used to assess the physical and thermodynamic properties of gas-vapour mixtures at a constant pressure. They are often used to assess the properties of moist air.
Which are the 5 factors indicated on a psychrometric chart?
- dry bulb temperature.
- wet bulb temperature (also known as saturation temperature)
- dew point temperature.
- relative humidity.
- moisture content (also known as humidity ratio)
- enthalpy (also known as total heat)
- specific volume (the inverse of density)
The psychrometric ratio is the ratio of the heat transfer coefficient to the product of mass transfer coefficient and humid heat at a wetted surface.
Every psychrometric chart includes vertical lines that represent the dry bulb temperatures. Air temperature increases from left to right. Every psychrometric chart also includes wet bulb temperatures. These lines are indicated at diagonals, and like dry bulb temperatures they increase from left to right.
It is the temperature recorded by a thermometer whose bulb is covered with a wick or cloth saturated with water and is exposed to a current of moving air. ... Hence WBT is always less than DBT for unsaturated air and is equal to DBT for saturated air. WBT value is affected by moisture content of air.
Psychrometric chart shows the inter-relation of all the important properties of air. Using the chart, it is easy to obtained psychrometric properties of air and it helps to decide the various processes to be followed to achieve required quality of air.
When relative humidity of the air is 100%, i.e the air is saturated, the dew point temperature (DPT) equals the wet bulb temperature (WBT), which is also equal to the dry bulb temperature.
Absolute humidity refers to the amount of water contained in a parcel of air and is commonly measured in grams of water per kg of dry air.
With the psychrometer it is possible to determine the humidity, ambient, wet bulb and dew point temperature. Measurements up to 60 °C are possible with the psychrometer.
Humidity ratio is the ratio of weight of moisture to the weight of dry air in the air–vapor mixture (e.g., pounds of water/pounds of dry air). Figure 1: Air saturation as a function of dry-bulb air temperature.
Dry bulb temperature (DBT or td): The temperature of moist air as measured by ordinary thermometer when placed in air is called dry bulb temperature.
The difference between the wet and dry-bulb temperatures recorded by a psychrometer; used in conjunction with the dry-bulb temperature as a measure of the relative humidity of the air.
MCQ: When dry bulb temperature (DBT) and wet bulb temperature (WBT) are measured, greater the difference between DBT and WBT, greater the amount of water vapour held in the mixture. smaller the amount of water vapour held in the mixture. same the amount of water vapour held in the mixture.
Psychrometry is the study of the thermodynamics of gas-vapor mixtures. Psychrometry is the study of the properties of moist air and is useful to engineers concerned with heating, cooling, and ventilating buildings. ... Psychrometry is the study of the thermodynamics of gas-vapor mixtures.
Psychrometrics is the science of air and water vapor and deals with the properties of moist air. ... This chapter presents a psychrometric chart, which shows the properties of moist air in terms of dry-bulb temperature, wet-bulb temperature, relative humidity, humidity ratio, and enthalpy.
When water evaporates, it rises and disperses into the surrounding air as the gaseous water vapor. Humidity is the presence of water vapor in the atmosphere. The more water evaporates in a given area, the more water vapor rises into the air, and the higher the humidity of that area is.
Some of the common psychrometric processes carried out on air are: sensible heating and cooling of air, humidification and dehumidification of air, mixing of various streams of air, or there may be combinations of the various processes.
Divide actual vapor pressure by saturation vapor pressure and multiply by 100 to obtain a percentage using the formula Relative Humidity (percentage) = actual vapor pressure/saturated vapor pressure x100. The resulting number indicates relative humidity.
The process in which the air is cooled sensibly and at the same time the moisture is removed from it is called as cooling and dehumidification process. Cooling and dehumidification process is obtained when the air at the given dry bulb and dew point (DP) temperature is cooled below the dew point temperature.