What is definition of bypass factor?

What is definition of bypass factor?

Bypass factor is the percentage of air that travels through a tube and fin coil without touching any coil surface.

What are four factors that affect coil bypass factor?

Factors affecting BPF:

• The number of fins provided in a unit length i.e. the pitch of the coil fins. The smaller the pitch, greater will be the number of fins per unit length coming in direct contact with the air and hence BPF decreases.
• The number of rows in a coil in the direction of flow.
• The velocity of flow of air.

What is the formula of logarithmic mean temperature in terms of bypass factor?

Clarification: Logarithmic mean temperature difference for the given arrangement is, Tm = td2 – td1 / loge [td3 – td1 / td3 – td2] As, BPF for the coil = [td3 – td1 / td3 – td2]

What is the value of bypass factor?

Bypass factor (BPF): It is defined as the ratio of loss in cooling or heating to the ideal cooling or heating. It is denoted by X. In the above-mentioned process, X = T 2 − T s T 1 − T s = ω 2 − ω s ω 1 − ω s = h 2 − h s h 1 − h s where Ts is the surface temperature of the coil.

What is the function of duct in air conditioning unit?

Ducts are conduits or passages used in heating, ventilation, and air conditioning (HVAC) to deliver and remove air. The needed airflows include, for example, supply air, return air, and exhaust air.

Which by-pass factor is possible?

This process is possible when air is passed over a cooling coil which is at a temperature below the dew point temperature of entering air. A part of air passes over the coil to reach ADP temperature and remainder air is bypassed.

Which of the following does not affected the bypass factor?

Which of the following does not affect the by-pass factor? Explanation: The weight of the apparatus has nothing to do with the by-pass factor. Pitch of the coil does affect the by-pass factor. And the velocity of air as well as fin spacing affects the by-pass factor.

What is heating and dehumidification?

The process in which the air is heated and at the same time moisture is removed from it is called as heating and dehumidification process. When the air comes in contact with the chemicals the moisture from the air is absorbed and since the chemicals emit heat, the DB temperature of the air increases.

What is the correct formula for bypass factor?

Bypass factor (BPF): X = T 2 − T s T 1 − T s = ω 2 − ω s ω 1 − ω s = h 2 − h s h 1 − h s where Ts is the surface temperature of the coil.

What is the bypass factor for cooling coil if TD?

What is the By-pass factor for heating coil, if td1 = 19°C, td2 = 25°C and td3 = 37°C? = 0.70588 = 0.7.

What is coil pressure drop?

A dirty coil has more airflow resistance than a clean coil. For example, a new, clean, residential three-ton cooling coil is rated by the manufacturer to have a pressure drop of . 30” w.c. at 1200 cfm. If you measure coil pressure drop and its . 50”, you know the coil is dirty and must be cleaned.