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Generate constant volumetric flow rate

**Library:**Simscape / Foundation Library / Thermal Liquid / Sources

The Volumetric Flow Rate Source (TL) block represents an
ideal mechanical energy source in a thermal liquid network. The source can maintain a constant
volumetric flow rate regardless of the pressure differential. There is no flow resistance and
no heat exchange with the environment. A positive volumetric flow rate causes the fluid to
flow from port **A** to port **B**.

The volumetric flow rate and mass flow rate are related through the expression

$$\dot{m}=\{\begin{array}{ll}{\rho}_{B}\dot{V}\hfill & \text{for}\dot{V}\ge 0\hfill \\ {\rho}_{A}\dot{V}\hfill & \text{for}\dot{V}0\hfill \end{array}$$

where:

*$$\dot{m}$$*is the mass flow rate from port**A**to port**B**.*ρ*_{A}and*ρ*_{B}are densities at ports**A**and**B**, respectively.*$$\dot{V}$$*is the volumetric flow rate.

The energy balance at the source is a function of the energy flow rates through ports
**A** and **B** and the work done on the fluid:

$${\varphi}_{A}+{\varphi}_{B}+{\varphi}_{work}=0,$$

where:

*ϕ*_{A}is the energy flow rate into the source through port**A**.*ϕ*_{B}is the energy flow rate into the source through port**B**.*ϕ*_{work}is the isentropic work done on the fluid.

The isentropic work term is

$${\varphi}_{work}=\frac{\dot{m}\left({p}_{B}-{p}_{A}\right)}{{\rho}_{avg}},$$

where:

*ϕ*_{work}is the isentropic work done on the thermal liquid.*p*_{A}is the pressure at port**A**.*p*_{B}is the pressure at port**B**.*ρ*_{avg}is the average liquid density,$${\rho}_{avg}=\frac{{\rho}_{A}+{\rho}_{B}}{2}\text{.}$$

There are no irreversible losses.

There is no heat exchange with the environment.

Controlled Mass Flow Rate Source (TL) | Controlled Pressure Source (TL) | Controlled Volumetric Flow Rate Source (TL) | Mass Flow Rate Source (TL) | Pressure Source (TL)