What does EnerTherm Engineering do?

EnerTherm Engineering is a UK-based industrial engineering company that designs and delivers thermal process solutions, energy auditing services, and bespoke thermal equipment for manufacturing and process industries. Services include energy audits, pinch analysis, process modelling, thermal design simulation, and project management.

What thermal products does EnerTherm Engineering manufacture?

EnerTherm Engineering manufactures process heaters, heat exchangers, thermal oxidisers, incinerators, condensers, dehydrators, and the Omni Vision industrial energy intelligence platform. All products are custom-designed for specific industrial applications and process requirements.

Does EnerTherm Engineering provide energy auditing services?

Yes. EnerTherm Engineering provides comprehensive energy audits, heat loss audits, and pinch analysis to identify energy waste, quantify potential savings, and prioritise capital investments in industrial facilities across sectors including chemical, pharmaceutical, food & beverage, and manufacturing.

What industries does EnerTherm Engineering serve?

EnerTherm Engineering serves chemical processing, pharmaceutical, food & beverage, oil & gas, power generation, automotive, textile, paper & pulp, general manufacturing, waste management, agriculture, healthcare, and mining & metals industries.

Where is EnerTherm Engineering located?

EnerTherm Engineering is headquartered in the United Kingdom and provides engineering services and thermal equipment to clients internationally.

Can EnerTherm Engineering help with industrial decarbonisation?

Yes. EnerTherm Engineering specialises in waste heat recovery system design, process optimisation for energy reduction, and net zero carbon roadmapping. They also provide ISO 14001 and ISO 50001 compliant energy management strategies.

does EnerTherm Engineering offer CFD simulation and thermal modelling?

Yes. EnerTherm Engineering provides Computational Fluid Dynamics (CFD) and Finite Element Analysis (FEA) for thermal equipment design. These simulations validate heat transfer performance before fabrication, reducing costly physical prototyping.

What is a thermal oxidiser and does EnerTherm Engineering supply them?

A thermal oxidiser is an industrial system that destroys volatile organic compounds (VOCs) and hazardous air pollutants (HAPs) through controlled high-temperature combustion. EnerTherm Engineering designs and manufactures regenerative, recuperative, and direct-fired thermal oxidisers for chemical, pharmaceutical, and manufacturing industries.

Does EnerTherm Engineering design custom process equipment?

Yes. EnerTherm Engineering provides bespoke engineering design of process vessels, heat exchangers, reactors, and thermal treatment systems from concept through to fabrication-ready drawings, as well as rapid prototyping and pilot plant commissioning.

What is EnerTherm Engineering's Omni Vision platform?

Omni Vision is EnerTherm Engineering's industrial energy intelligence platform. It provides turnkey utility metering, CO2 tracking, and AI-powered production KPI intelligence for industrial compliance monitoring and operational optimisation.

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[Natural Convection]

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Concentric Cylinders — Natural Convection

Heat transfer across the annular gap between two concentric cylinders via effective conductivity.

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Orientation alone can halve your cooling: the same plate at the same ΔT convects about twice as well with its hot face up as with its hot face down.

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Concentric Cylinders — Natural Convection

Calculates the natural-convection heat transfer across the annular gap between two long concentric cylinders held at constant temperatures $T_{i}$ (inner) and $T_{o}$ (outer). The Raithby–Hollands method represents the buoyant flow in the gap as an enhanced conduction: heat is conducted through a stationary fluid of effective conductivity $k_{e f f} > k$ .

Gap Rayleigh Number

Properties are evaluated at the mean temperature $T_{f} = (T_{i} + T_{o}) /2$ . The characteristic length is the radial gap $b = (D_{o} - D_{i}) /2$ :

R a_{d} = \frac{g β ( T _{i} - T _{o} ) b ^{3} P r}{ν ^{2}}

Modified Rayleigh Number and Effective Conductivity

R a_{c}^{*} = \frac{[ ln ( D _{o} / D _{i} ) ] ^{4}}{b ^{3} ( D _{i}^{- 3/5} + D _{o}^{- 3/5} ) ^{5}} R a_{d}

\frac{k _{e f f}}{k} = 0.386 (\frac{P r}{0.861 + P r})^{1/4} (R a_{c}^{*})^{1/4}

The correlation is valid for $1 0^{2} \leq R a_{c}^{*} \leq 1 0^{7}$ ; below $R a_{c}^{*} = 100$ buoyancy is negligible and $k_{e f f} = k$ (pure conduction).

Heat Rate

Q = \frac{2 π k _{e f f} L ( T _{i} - T _{o} )}{ln ( D _{o} / D _{i} )}

References

Raithby, G. D. and Hollands, K. G. T., A General Method of Obtaining Approximate Solutions to Laminar and Turbulent Free Convection Problems, Advances in Heat Transfer, Vol. 11, Academic Press, pp. 265–315, 1975.
Incropera, F. P. and DeWitt, D. P., Fundamentals of Heat and Mass Transfer, eqs. 9.58–9.60.

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Frequently asked questions

Heat transfer across the annular gap between two concentric cylinders via effective conductivity. Enter your inputs and press Calculate — the worked solution shows every step of the method with your numbers substituted in.

When there is no fan, pump or significant draught — enclosures, outdoor surfaces on still days, passive heat sinks. If there is any imposed flow, compare the two mechanisms: when Gr/Re² is well below one, forced convection dominates and the forced-convection calculators are the right tools.

No — it computes the convective part only. At typical natural-convection coefficients of 2–10 W/m²·K, radiation from a painted or oxidised surface is often the same order of magnitude, so total heat loss should add a radiative term from the Radiation calculators.