Air Coolers:

Air flow accessories - don't overlook louvers,screens and fan guards when calculating fan HP

Box header design - limit of process temperature change

Connecting bundles of existing coolers for a new service

Fan drive changes that increase capacity of existing cooler

Fan drive noise - suggestions on how to reduce

Maximum motor HP for a fan

Maximum tube wall temperature for wrap-on fins

Optimum number of tube rows

Overall heat transfer rate estimate for hydrocarbons

When do bare tubes become more efficient than fin tubes?

When To limit number of tube passes in air coolers

When to use wind coolers


Estimate - critical heat flux for propane chillers

Avoid mist flow boiling inside tubes

Kettle reboiler - liquid carryover problem solutions

Kettle reboiler - shell nozzle arrangement problem

Kettle reboiler - shell vapor outlet nozzle location

Kettle reboiler - sizing shell vapor space

Kettle reboiler - use supports or baffles?

Kettle reboiler - undersized shell effects

Estimate - pool boiling heat transfer coefficient for hydrocarbons

Large boiling temperature difference problems

Lowest limit of boiling temperature difference

Minimum Boiling Temperature Difference

Vertical thermosyphon - calculate pressure drop at the outlet nozzle

Vertical thermosyphon - choking two phase flow with small outlet nozzle

Vertical thermosyphon - design for smaller liquid preheat zone

Vertical thermosyphon - minimum recirculation rate

Vertical thermosyphon - check for liquid preheat zone

Vertical thermosyphon - who sets recirculation rate


What diameter to use to start design of a coil

Estimate - gas heat transfer coefficient inside tubes

Estimate - hydrocarbon gas heat transfer coefficient in shell side

Estimate - liquid hydrocarbon heat transfer coefficient in tubes

Estimate - latent heat of hydrocarbons

Estimate - liquid thermal conductivity of light hydrocarbons

Estimate - optimum flow velocity for gas inside tubes

Estimate - overall liquid hydrocarbon heat transfer coefficient in shell & tube

Estimate - tube length that lowers tube pressure drop

How to calculate excess surface and overdesign surface

Use superficial velocities to calculate best heat transfer flow pattern

L/D equation for heat Transfer coefficient inside tubing

LMTD correction factor charts for TEMA G and J type shells

Low LMTD correction factor for divided flow

What is the lowest LMTD correction to use in shell & tube

Minimum flow area for shell side inlet nozzle

How to calculate performance of heat exchangers with plugged tubes

How to increase heat transfer for low Reynolds numbers

Calculate when to use seal bars on a bundle to increase heat transfer

Calculate S & T bundle diameter from number of tubes

Equation for calculating tube count in shell & tube

Check for hot tube wall temperature of cooling water

Sometimes larger tubes are better than small ones

U-tube Bend Area Equation

Weighted MTD


Avoid small baffle cuts in S & T condensers

Estimate - Condensing heat transfer coefficient for hydrocarbons inside tubing

Maximum heat transfer rate inside tubes for total condensation

Quick estimate for reflux condenser LMTD in air cooler

Reflux (Knockback) condenser comments

Steam condenser types

Sulfur condenser - design within tube velocity limits

Warning about small temperature pinch points in condensers

When to slope single tube pass tubes in condensing service

Zone those condensers


Design temperatures of carbon steel and low alloy tubes and tubesheet

Design temperatures of nonferrous tubes and tubesheet

Equations for how baffle cuts expressed.

Benefits of using rotated square pitch in shell & tube

Caution when using a longitudinal baffle in the shell side

Using turbulators for tube side laminar flow

Discussion of types of triple segmental baffles in shell & tube

Check entrance and exit space for shell nozzles

Horizontal vs vertical baffle cut in shell & tube

Is expansion joint required in the shell of a fixed tube sheet?

Increasing capacity of existing shell & tube exchangers

Locating vents on the shell side of vertical exchangers

Longitudinal Baffle Heat Conduction Cures

Optimun gasket location for flanges

Reinforcing rods as tube inserts to increase heat transfer

Shell side impingement protection

Special shell & tube heat exchanger type (NTIW)

When to consider by-pass strips in shell & tube bundle

What is too large of temperature change in 2 tube passes ?

When to rotate square tube pitch in shell & tube exchanger

Heat Recovery:

Gas Turbine Boiler - Calculation Start

Deciding on what fin spacing to use

Estimate of nozzle size for HRSG

Face area estimate for HRSG units

Maximum exhaust gas temperaure for steel fin tubes

When to use bare tubes in waste heat boilers


Cooling water flowing inside 304SS U-tubes

Pressure Drop:

Allowing for fouling in pressure drop calculations

Allowable pressure drop suggestions

Allowable shell side pressure drop if a multi-leaf(a.k.a. lamaflex) long baffle is used

Better baffle window pressure drop equation

Designing for better use of tube pressure drop

Effect of 1st tube rows on shell nozzle pressure drop

Pressure drop on kettle side

Reducing high shell side pressure drop in fixed tube sheet exchangers

Use impingement rods instead of plate to lower shell press. drop

What design pressure drop to use for heavy liquids inside tubes

Maximum velocity inside tubes

Calculate shell nozzle pressure drop

Improve shell side pressure drop calculations

Vibration of Bundle:

Best design feature to prevent bundle vibration

Features of a new S & T bundle that replaces bundle that vibrated

Vibration cure when designing shell & tube bundles

Conditions likely to cause shell & tube bundle vibration

Cures for vibration in existing bundle


Allocation of streams in shell & tube

Articles published by Dale Gulley

Avoid these fluids when using lowfin tubing

Best heat transfer flow pattern

Fouling factors for liquid hydrocarbons

Fouling factors for water

Check liquid thermal conductivity at high reduced temperatures

Check piping connections when there is under-performance

Evaluating an exchanger for a new service

Check heat release curve data for skipping over dewpoints and bubblepoints

When will exchangers with low-fins be more economical than exchangers with bare tubes?

Maldistribution of tube-sde flow

Problems with excess heat exchanger surface

Purchasing warning for shell & tube exchangers

What is the minimum velocity inside tubing for slurries?

Suggestions for low-fins and potential S & T bundle vibration

Choose shell & tube or multi-tube heat exchangers

Thermal design problem with shell side long baffle

Trouble shooting article in Hydrocarbon Processing

Undersurfaced S&T quote

When to add shell in Series

When to consider a long baffle in the shell

Which stream goes inside the tubes of gas/gas exchangers?

Viscous flow - use more pressure drop than usual

Weighted MTD

Why did performance decline in a TEMA type F,G or H type shell?

Zone those condensers

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