mass flow weighted average

Dear Paul,

In SAM manual for physical modelling,page 11. inlet loop temperature equals either:
power cycle outlet
storage system outlet
mass flow rate weighted average of storage
solar field outlet

what is meaning by mass flow rate weighted average?
and what is difference between mass flow rate and weighted average?

Dear Saeed,

The "mass-flow weighted average of the storage and power cycle outlet temperatures" is the weighted average value of the storage and power cycle temperatures relative to the HTF mass flow rate. In other words, the average value of the temperature is weighted by the mass flow rate.

Best regards,
Paul.