How do you use affinity laws?

Stated simply, the Affinity Laws say:

  1. The flow (GPM) varies proportionally with the change in speed. This means that twice the speed is twice the flow. …
  2. The pump head (pressure) varies with the square of the change in the speed. …
  3. The power requirement (horsepower or kilowatts) varies by the cube of the change in speed.

What is pump affinity laws?

The affinity laws (Also known as the Fan Laws or Pump Laws) for pumps/fans are used in hydraulics, hydronics and/or HVAC to express the relationship between variables involved in pump or fan performance (such as head, volumetric flow rate, shaft speed) and power. They apply to pumps, fans, and hydraulic turbines.

How is Affinity Law calculated?

This law is expressed with the following formula: H1/H2 = (N1/N2)2 or (D1/D2)2 Where H is equal to head, N is equal to shaft speed, and D is equal to impeller diameter.

Do affinity laws apply to compressors?

If the compressor flow, head and efficiency characteristics are known at a given speed, then merely applying the affinity laws at an alternate speed will produce a new curve representing the compressor performance at that speed. This is the same concept behind head and flow coefficients.

How is pump power calculated?

Pump Power calculation Formula: Pump Power P( kW ) = q( m 3 / hr ) x ρ( kg / m 3 ) x g( m 2 / s ) x h( m ) x p( Pa ) / 3600000. The same way pump power in horsepower formula can be written as, Pump Power P( HP ) = q( m 3 / hr ) x ρ( kg / m 3 ) x g( m 2 / s ) x h( m ) x p( Pa ) / 2685600. Also above pump power is required to lift the liquid to head meters.

What does an impeller do?

WHAT DO IMPELLERS DO? Impellers pump cold water into your boat’s engine to cool it down while in use. If you have a bad impeller it can cause big problems.

What is the fan law?

The Fan Laws are a group of useful equations for determining the effects of a change in the speed, the diameter of the fan and the density of air in the system. They are most useful for determining the impact of extrapolating from a known fan performance to a desired performance.

What is the use of pump?

Today, the pump is used for irrigation, water supply, gasoline supply, air conditioning systems, refrigeration (usually called a compressor), chemical movement, sewage movement, flood control, marine services, etc.

What is pump parameter?

Pump Parameters. Pump operation and performance can best be described by a few fundamental parameters; flow rate, pressure, head, power, and efficiency. Volume flow rate (Q), also referred to as capacity, is the volume of liquid that travels through the pump in a given time (measured in gallons per minute or gpm).

What is affinity in marriage?

The relationship that a person has to the blood relatives of a spouse by virtue of the marriage. Direct affinity exists between the husband and his wife’s relations by blood, or between the wife and the husband’s relations by blood. …

How is pump impeller diameter calculated?

What is pump curve?

Pump curves are essentially data about a given pump’s ability to produce flow against certain head. When you’re reading a curve, the pump’s flow rate will be on the top and bottom and its height to push is on the sides.

Does NPSH vary with pump speed?

NPSH-Required increases by the 4/3 power of the pump speed, for a given flow rate and Suction Specific Speed, so assuming that the value of the system NPSH-Available is fixed, lower pump speed can increase the NPSH-Margin, and therefore, pump reliability.

Does pump efficiency change with speed?

Pump Performance Pump efficiency also increases with pump rotational speed, especially high speeds. The increase is not as pronounced at 3,600 rpm and below. Specific speed also affects head-capacity curve shape. … High speeds (6,000 and higher) produce steep curves.

What is specific speed of pump?

Specific Speed is a dimensionless rating of pump discharge performance derived from an equation involving shaft speed, flow rate and differential head at a pump’s Best Efficiency Point. It is an important factor used in the design and selection of pumps and impellers.

What is pump formula?

Titan Series Pump Formula is a caffeine-free pre-workout that helps to increase nitric oxide levels, filling your muscles with the oxygen and nutrients they need to grow. Pump Formula can help your muscles fight off fatigue so that you can train harder, longer.*

What is pump capacity?

Pump capacity is a term used to define the flow rate through a pump at its designed conditions. It describes the volume of liquid that is allowed to travel through the pump in a given time. … Some of the most common units of pump capacity are: Gallons per minute (gpm) Liters/minute (L/min)

What is pump head?

Head is the height to which a pump can raise water straight up. Water creates pressure or resistance, at predictable rates, so we can calculate head as the differential pressure that a pump has to overcome in order to raise the water.

What are the types of impellers?

Types

Where are impellers used?

An impeller is a rotating component equipped with vanes or blades used in turbomachinery (e. g. centrifugal pumps). Flow deflection at the impeller vanes allows mechanical power (energy at the vanes) to be converted into pump power output.

What is impeller and propeller?

A propeller is a type of fan that propels fluid by pushing against it, converting rotational force into a linear motion. An impeller is a type of rotor that is typically part of a pump and creates a sucking force, i.e. drawing liquid into a vehicle or engine.

What is Sisw and DIDW?

Double Inlet Double Width Fans give the same pressure rise but double the flow of a single inlet single width fan. … The performance is quite simple: a DIDW Fan gives the same pressure rise but double the flow of a single inlet single width (SISW) fan.

How much force can a fan generate?

In high mode, the fan has 4.22 volts across it with a current of 2.12 Amps. This gives a power of 8.95 Watts. In low mode, the fan potential is 3.44 volts with a current of 1.59 Amps. This gives a power of 5.47 Watts.

How many fan laws are there?

Fan laws are mathematical formulas for predicting system changes when airflow adjustments are made. There are three laws that cover various system properties, ranging from fan speed (rpm) to motor amperage. In this article, we’ll look at Fan Law 2, which predicts new static pressure after making airflow changes.

What are the 4 types of pumps?

Types of Pumps

What are the 2 main classification of pumps?

Pumps are divided into 2 major categories: Dynamic and Positive Displacement (aka Displacement).

How do pumps work?

Pumps work by creating a vacuum in which ambient air pressure forces the liquid. All pumps work by creating areas of low pressure. In a centrifugal pump, centrifugal force accelerates the water to the outside of the impeller creating a low pressure at the eye or centre of the impeller.

What is flow and head?

The flow rate is the effective volume flowing per unit of time through the discharge connection of a pump. … The total head is the effective mechanical energy transferred by a pump to the fluid as a function of the weight force of the fluid.

What is pump flow rate?

The flow rate (Q) of a centrifugal pump is the useful volume flow delivered by the pump via its outlet cross-section (see Pump discharge nozzle). … The unit of the flow rate is m3/s; in centrifugal pump engineering the units m3/h and l/sare more common.

What is NPSH of a pump?

The difference between inlet pressure and the lowest pressure level inside the pump is called NPSH: Net Positive Suction Head. NPSH is therefore an expression of the pressure loss that takes place inside the first part of the pump housing.