Method: Energy balance Q = ṁ·cp·ΔT; LMTD with Bowman's analytical F-factor for N shells in series; tube-side film coefficient by Dittus–Boelter (Nu = 0.023·Re^0.8·Pr^0.3), shell-side by the Kern method (Nu = 0.36·Re^0.55·Pr^(1/3)); area sized to the over-surface target (U is calculated, the area is the design lever); effectiveness via the ε-NTU relation.

Method: Tube-side Darcy–Weisbach with a Petukhov friction factor f = (1.82·log10(Re) − 1.64)^-2, plus 4 velocity-head return losses per pass; shell-side by the Kern correlation f = exp(0.576 − 0.19·ln Re) over (Nb+1) crossings per shell.

Method: Tube count from TEMA bundle constants Db = do·(Nt/K1)^(1/n1) on a 1.25·do triangular pitch; shell ID = Db + clearance; baffle spacing optimised within the 0.2–0.5·Ds band and capped by the TEMA RCB-4.52 maximum unsupported span; minimum plate thickness from TEMA Table R-4.41.

Method: Shell & 2:1 ellipsoidal head by ASME VIII-1 internal-pressure (membrane) formulas; tubesheet by bending t = F·G·√(P/S); girth flange by ASME VIII-1 Appendix 2 (spiral-wound gasket m/y); differential expansion ΔL = L·α·ΔT with restrained stress σ = E·α·ΔT. Steel 20 allowables (GOST 34233); design pressure = 1.1 × operating.

Method: Bore from continuity at the target velocity, d = √(4Q/πv), rounded to the nearest DN; impingement-plate need decided by the inlet momentum ρv² against the TEMA limit of 2230 kg/(m·s²).

Method: Schematic generated from the computed configuration — shells in series, tube passes, baffle count/spacing and counter-current nozzle positions. Line colours track stream temperatures; not drawn to mechanical scale.

Method: To-scale drawings built from the calculated dimensions (auto-synced from the main design); the sliders let you override locally to explore variants. Geometry rendering only — no recalculation of duty or stresses here.