P&K 3781

P&K 3781 by P&K is a specialized engineering application for assessing exhaust stack and chimney discharge in accordance with the principles of VDI 3781. It helps engineers and consultants determine minimum chimney heights, evaluate discharge conditions, and document compliance for permitting and design reviews.

Key capabilities:

• Guided workflows for VDI 3781–based assessments of minimum stack height and discharge.
• Input support for flue gas temperature, volumetric flow, exit velocity, and fuel or source type.
• Consideration of building dimensions, roof geometry, and nearby structures that influence dispersion and re-entrainment.
• Scenario management for quick comparisons and sensitivity checks.
• Clear, audit-ready reports that document assumptions, formulas, and results.
• Built-in unit handling and validation checks to reduce input errors.
• Optional visual aids to illustrate discharge points relative to buildings.

Who it’s for:

• Environmental and HVAC engineers, stack designers, and permitting specialists.
• Facility operators and consultants preparing compliance documentation.

Benefits:

• Consistent, standards-aligned results that streamline reviews and approvals.
• Faster iterations during design and retrofit projects.
• Transparent outputs that support regulatory submissions and stakeholder communication.

Typical uses:

• Determining minimum chimney heights for boilers, CHP units, and process exhausts.
• Verifying discharge parameters for permit applications.
• Evaluating the impact of building changes on exhaust dispersion and nuisance potential.

P&K 3781 is developed by P&K. The most popular versions of this product among our users are: 5.4, 6.0 and 6.2. The name of the program executable file is pk_3781.exe.