Calculator
Heat Transfer
LMTD Calculator
Calculate log mean temperature difference for countercurrent and parallel heat exchangers, with unit conversion, end differences, and a temperature diagram.
ΔTₗₘ = (ΔT₁ − ΔT₂) / ln(ΔT₁/ΔT₂)
FOR THE WORK OF CHEMICAL ENGINEERING
Chemical engineering,
calculated clearly.
From the first assumption to the final answer.
Practical calculators, explained methods, and worked examples for your next engineering problem.
Clear units Stated assumptions Worked examples
FIND YOUR STARTING POINT
A number to calculate.
A concept to understand.
01 / THE TOOLBOX
Less setup. More solving.
Go straight to the calculation you need.
Calculator
Fluid Flow
Reynolds Number Calculator
Calculate Reynolds number with dynamic or kinematic viscosity, SI and engineering units, explicit diameter basis, and circular-pipe flow-regime guidance.
Re = ρ v D / μ
Calculator
Heat Transfer
Sensible Heat Duty Calculator
Calculate sensible heating or cooling duty from mass flow, specific heat capacity, and temperature change, with SI and engineering units and worked steps.
Q = ṁ cₚ ΔT
Calculator
Fluid Flow
Pipe Velocity Calculator
Calculate mean pipe velocity from actual volumetric flow and internal diameter, with SI and engineering units, flow area, worked steps, and an example.
v = 4Q / πD²
Calculator
Engineering Units
Engineering Unit Converter
Convert SI and engineering units with quantity checks, separate temperature readings and differences, traceable conversion factors, and worked steps.
SI ↔ Engineering units
Calculator
Fluid Flow
Pump Hydraulic and Shaft Power Calculator
Calculate hydraulic power, mechanical pump shaft power, and pump losses from actual flow, total pump head, fluid density, gravity, and pump efficiency.
P = ρgQH / η
02 / CONNECT THE CONCEPTS
One discipline. Many ways in.
Find tools and explanations together, organized by topic.
01
Heat Transfer
Heat duty, LMTD, heat exchanger area, and heat loss calculations.
7 resources
02
Fluid Flow
Pipe velocity, Reynolds number, fluid head, and pressure drop calculations.
8 resources
03
Engineering Units
Unit conversions, dimensional analysis, and absolute and gauge pressure.
8 resources
04
Material & Energy Balances
Mass and molar flow, mixing, and material and energy balances.
9 resources
05
Thermodynamics & Properties
Physical property data, vapor pressure, and thermodynamic model selection.
3 resources
06
Separations & Distillation
Vapor-liquid equilibrium, McCabe-Thiele diagrams, reflux, and stage estimates.
1 resource
07
Process Equipment
Pumping, vessel geometry, and process equipment estimates.
2 resources
08
Engineering Computing
Engineering calculations in Excel, Python, and DWSIM, and calculation verification.
2 resources
03 / BEHIND THE ANSWER
Build your understanding.
Practical reading for the questions a result brings up.
Guide
Pipe Velocity Worked Example Using Actual Internal Diameter
Average pipe velocity is the volumetric flow rate divided by the bore area (V = Q/A). For 100 US gpm in a pipe…
Guide
Fluid Flow Calculations: Velocity, Reynolds Number, and Pressure Drop
Pipe-flow calculations chain three quantities: the mean velocity from the continuity equation, the Reynolds number that fixes the flow regime, and the friction…
Guide
Heat Transfer Calculations: Heat Duty, LMTD, and Exchanger Area
Heat exchanger sizing links three quantities in one equation: the duty Q = U·A·ΔT, where the temperature difference is the log mean of…
- 01
Start with the right inputs.
Keep the basis, units, and operating conditions in view.
- 02
See the reasoning.
Follow the equations, assumptions, and worked examples.
- 03
Take the next step.
Move between a calculator and its underlying concepts.
YOUR ENGINEERING REFERENCE10 calculators32 guides & examples8 engineering topics