Thermodynamics & Heat Transfer

LMTD Thermal Simulator

Examine heat exchanger physics using the Log Mean Temperature Difference method. Control fluid temperatures, configurations, exchanger dimensions, and map thermal profiles.

Configuration

Counter-Flow

Fluid flow alignment

Thermal Capacity

Balanced

Energy balance check

Output

CSV

Export ready

Parameters

Flow Arrangement

Hot Fluid Inlet (Th,in)120 °C

80300

Hot Fluid Outlet (Th,out)80 °C

40200

Cold Fluid Inlet (Tc,in)20 °C

5100

Cold Fluid Outlet (Tc,out)55 °C

15180

Coeff. of Heat Transfer (U)250 W/m²·K

501000

Exchanger Area (A)10 m²

1150

Exchanger length scan

Thermodynamic Formulations

Log Mean Temp Diff

LMTD = (dT1 - dT2) / ln(dT1 / dT2)

Heat Transfer Rate

Q = U * A * LMTD

Parallel Flow Terminal

dT1 = Th,in - Tc,in; dT2 = Th,out - Tc,out

Counter Flow Terminal

dT1 = Th,in - Tc,out; dT2 = Th,out - Tc,in

Counter-flow heat exchangers always exhibit higher LMTD values than parallel-flow ones under matching conditions, enabling a more compact design.

At current scanner position (0%), Th = 120°C, Tc = 55°C, local difference ΔT = 65°C.

Exchanger Schematic & Flow Vector

Log Mean Temp Diff

62.47°C

Heat Transfer Rate (Q)

156.17kW

Delta T1 (dT1)

65.0°C

Delta T2 (dT2)

60.0°C

Fluid Temperature Profiles

Temperature Profile Data

Position (%)	Hot Fluid Temp (°C)	Cold Fluid Temp (°C)	Temp Difference ΔT (°C)
0%	120°C	55°C	65°C
10%	112.8°C	48.7°C	64.1°C
20%	106.7°C	43.3°C	63.3°C
30%	101.3°C	38.7°C	62.7°C
40%	96.8°C	34.7°C	62.1°C
50%	92.8°C	31.2°C	61.6°C
60%	89.4°C	28.3°C	61.2°C
70%	86.5°C	25.7°C	60.8°C
80%	84°C	23.5°C	60.5°C
90%	81.9°C	21.6°C	60.2°C
100%	80°C	20°C	60°C