Mechanical Fluids & Heat Transfer Calculators
NPSH, pipe fitting losses, log mean temperature difference, thermal expansion and weir discharge — the fluid and heat transfer checks behind reliable plant.
Condensate Line Calculator
Condensate drain line sizing including the flash steam released as hot condensate drops to atmospheric, checked against the gravity capacity of the line at the slope you enter.
f_flash = h_fg/(h_fg + c_p·ΔT); load = m·(1−f_flash)·(1+S) Compressed Air Receiver Sizing Calculator
Size an air receiver and find how much free air it releases over the pressure swing, the run time it gives the network, and the volume a required run time needs.
V_free = V x (P1_abs - P2_abs) / P_atm Water Hammer Surge Calculator
Surge pressure from a valve closure or pump trip, with the rapid-closure (Joukowsky) and slow-closure regimes separated by the pressure-wave round trip.
dP = rho*a*dV (t <= 2L/a) | 2*rho*L*dV/t (t > 2L/a) Expansion & Pressurisation Vessel Sizing Calculator
Size the vessel that absorbs a closed water loop’s thermal expansion, with the usable pressure fraction and the pre-charge the sizing depends on.
V_t = (beta * dT * V_s) / (1 - P1/P2) NPSH Calculator
Net positive suction head available at the pump from pressure, vapour pressure, static head and suction friction.
NPSH(A) = (Pa - Pv)/(rho g) + Hs - Hf Pipe Fitting Loss Calculator
Head loss, pressure drop and equivalent length for a pipe fitting from its K-value and flow velocity.
hL = K V^2/(2g) ; Le = K D / f LMTD Calculator
Log mean temperature difference for a counter-flow heat exchanger and the heat transfer area it implies.
dTlm = (dT1 - dT2)/ln(dT1/dT2) ; A = Q/(U F dTlm) Pipe Thermal Expansion Calculator
Free linear expansion of a pipe run for a given material, length and temperature rise, in millimetres and per 100 m.
dL = alpha x L x dT Weir Flow Calculator
Discharge over rectangular, contracted, V-notch and Cipolletti weirs from the head above the crest.
Q = 1.84 L H^1.5 (rectangular) ; Q = 1.38 H^2.5 (90 degree V-notch)