Periodic energy usage. the 168-vector w gives the hourly electricity consumption of a manufacturing plant, starting on sunday midnight to 1am, over one week, in mwh (megawatt-hours). the consumption pattern is the same each day, i. e., it is 24-periodic, which means that wt+24 = wt for t = . let d be the 24-vector that gives the energy consumption over one day, starting at midnight. (a) use vector notation to express w in terms of d.

For the closed feedwater heater below, feedwater enters state 3 at a pressure of 2000 psia and temperature of 420 °f at a rate of ix10 ibhr. the feedwat extracted steam enters state 1 at a pressure of 1000 psia and enthalpy of 1500 btu/lbm. the extracted er leaves at an enthalpy of 528.7 btu/lbm steam leaves as a saturated liquid. (16) a) determine the mass flow rate of the extraction steam used to heat the feedwater (10) b) determine the terminal temperature difference of the closed feedwater heater