Mass Flow Rate Equation Fluids

Ch 5 lesson a page 5 equations for determing the mass flow rate.

Mass flow rate equation fluids. Mass flow rate is the rate of movement of a massive fluid through a unit area. The formula for mass flow rate is given. If the fluid initially passes through an area a at velocity v we can define a volume of mass to be swept out in some amount of time t. P ρ q g h 4 with specific weight expressed as.

Other common units for measurement of mass flow rate include kilograms per second and pounds mass per hour. Unit mass energy of a system. Density is just the ratio of the mass of a chunk of fluid to its volume. V 30 m s and.

The mass flow rate formula is given by m ρva. The mass flow rate is related to the volumetric flow rate as shown in equation 3 2 where r is the density of the fluid. Mass flow rate can be used to calculate the energy flow rate of a fluid. Energy flow rate has si units of kilojoule per second or kilowatt.

However in real fluids compressibility effects limit the speed at which a flow can be forced through a given area. M 800 30 0 20. Flow rate is the volume of fluid per unit time flowing past a point through the area a. Mass flow depends on the density velocity of the fluid and the area of the cross section.

Mass flow rate density velocity area of the cross section m ρ v a. If the volumetric flow rate is in cubic feet per second and the density is in pounds mass per cubic foot equation 3 2 results in mass flow rate measured in pounds mass per second. Density of the fluid. M r a v t to determine the mass flow rate mdot we divide the mass by the time.

A 20 cm 2 0 20 m 2. The volume of the cylinder is ad and the average velocity is v d t v d t so that the flow rate is q ad t a. Meaning it is the movement of mass per unit time. The cool part is that the density is also the ratio of the mass flow rate to the volumetric flow rate.

We can determine the value of the mass flow rate from the flow conditions. Determine the mass flow rate of a given fluid whose density is 800 kg m 3 velocity and area of cross section is 30 m s and 20 cm 2 respectively. Let s begin with the concept of density. The volume v is.

Volumetric flow rate is a new idea but not a scary one. ρ density kg m 3 q volume flow rate m 3 s combining 1 2 and 3 the power gained by the fluid from a pump or fan can be expressed as. Here the shaded cylinder of fluid flows past point p in a uniform pipe in time t. V a v t a units check gives area x length time x time area x length volume.

Mass flow rate for an ideal compressible gas. It s units are kg s. Mass flow rate m can be expressed. M ρ q 3 where.

γ ρ g 5. Given values are ρ 800 kg m 3. M 4800 kg s. The mass m contained in this volume is simply density r times the volume.

Where.