Refrigeration, air-conditioning and cooling technology - 2007.pdf

PLH_KKK_32_85.QXP 25.05.2007 10:11 Uhr Seite 76EXAMPLES FOR THE PUMP SELECTION IN THE VAPORISER CIRCUITVaporiser circuit with ice storageTo ensure the functional sequence, anAntifrogen L / water mixture (40 % to 60 %)is selected as the fluid to be pumped.The volume flow is determined as follows:Formula for volume flow V˙PUStep 1(15.41) 0.50B = 2.80 · 3.49(32.68) 0.25 · (9) 0.125V·PU =Q· N1.02 · ∆ϑm 3 /hStep 2C Q ≈ C H ≈ (2.71) -0.165 · (log 3.49)3.15 ≈ 0.98Abbreviation Description1.02 Spec. heat capacity [Wh/kgK]∆Dimensioned temperature difference[K]10-20 K for standard systemsQ NHeat demand [kW]CalculationStep 332.68Q W = = 33.48 m 3 /h0.9769H W = = 9.22 m0.98V·PU =1001.02 · 3m 3 /hV·PU = 32.68 m 3 /hThe system pressure losses are assumed to be9 m from the calculation model. The preliminarypump data is to be determined with the followingsteps.Ice storage operation with 100 kW and a fluid temperature of -4° CValve 2MValve 3MValve 4MIce bank 1 Ice bank 2MValve 1MValve 5Ice bank pumpCapacitorsVaporiserVaporiser pump76 Subject to change without prior notice 02/2007 WILO AG