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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[Radiation]

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Coaxial Parallel Disks

Net radiant heat exchange between two coaxial, directly-opposed gray disks.

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Radiation scales with absolute temperature to the fourth power — a surface at 600 °C radiates over five times more than the same surface at 300 °C.

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Coaxial Parallel Disks

Computes the net radiant heat exchange between two isothermal gray disks of radii $r_{1}$ and $r_{2}$ , mounted coaxially and directly opposed, separated by a gap $D$ .

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With the dimensionless radii

R_{1} = \frac{r _{1}}{D}, R_{2} = \frac{r _{2}}{D}, S = 1 + \frac{1 + R _{2}^{2}}{R _{1}^{2}}

the shape factor from disk 1 to disk 2 is

F_{12} = \frac{1}{2} ⎩ ⎨ ⎧ S - [S^{2} - 4 (\frac{r _{2}}{r _{1}})^{2}]^{1/2} ⎭ ⎬ ⎫

For two equal disks with $R_{1} = R_{2} = 1$ this gives $F_{12} \approx 0.382$ ; as the disks grow large relative to the gap the factor approaches unity.

Net Radiant Exchange

Q = \frac{σ ( T _{1}^{4} - T _{2}^{4} )}{\frac{1 - ε _{1}}{ε _{1} A _{1}} + \frac{1}{A _{1} F _{12}} + \frac{1 - ε _{2}}{ε _{2} A _{2}}}

with $σ = 5.670374 \times 1 0^{- 8} W/m^{2} K^{4}$ , $A_{1} = π r_{1}^{2}$ , $A_{2} = π r_{2}^{2}$ , and temperatures in Kelvin. When both surfaces are black this reduces to $Q = σ A_{1} F_{12} (T_{1}^{4} - T_{2}^{4})$ .

References

Rohsenow, W.M., Hartnett, J.P. & Cho, Y.I., Handbook of Heat Transfer, 3rd ed., McGraw-Hill, 1998.
Incropera, F.P. & DeWitt, D.P., Fundamentals of Heat and Mass Transfer, Wiley.

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Frequently asked questions

Net radiant heat exchange between two coaxial, directly-opposed gray disks. Enter your inputs and press Calculate — the worked solution shows every step of the method with your numbers substituted in.

A gray surface has an emissivity that is constant across wavelength, so one number ε between 0 and 1 characterises how it emits and absorbs. It is the standard engineering idealisation; real oxidised metals and painted surfaces follow it closely enough for plant calculations.

Use the built-in table as a starting point: polished aluminium is around 0.05, oxidised steel around 0.8, painted or anodised surfaces around 0.9. Surface condition dominates — use the in-service condition, not the as-machined one.