Flue gas duct sizing calculation. Guide for how to design a ductwork system.

Flue gas duct sizing calculation. This paper focuses on the analysis of flue gas duct pressure reduction using baffles and comparing it with a no-baffles case. This web application calculate power required for air flow and also determine performance for different fan speed and diameter based on Affinity Laws. This density difference generates a pressure difference, known as draft, which promotes the flow of flue gas from the Fired Heater to the atmosphere. Oct 17, 2014 · Calculate velocities in circular and rectangular ducts - imperial and SI-units - online calculator. The quantity of flue gases is also […] Easy to Use Online Ductulator / Duct Size Calculator. Once the velocity’s computed, the system losses can be calculated following the procedure previously described. Call Environmental Chimney Service in Asheville NC at 828-243-0098 to solve this problem. Jul 3, 2018 · Duct sizing, duct calculation, duct design, energy efficient ductwork design. During analysis of a chimney system one must first determine the mass flow ratio of flue gases per kg of fuel burned. The temperature difference between the outside air and the inside air creates a "natural draft" forcing air to flow through the building. The size of the stack is directly influenced by this factor, since a larger stack will be required to create sufficient draft to overcome these flue losses and maintain -2. Gas Vent and chimney products for capacities to 100 million Btu per hour The Chimney Liner and Flue Pipe Length Calculator will take out the guesswork and provide the perfect suggestions for the proper length for rigid chimney liners, stove pipes and Class A chimney pipes. Full worked example included with CFD simulations to optimise your design to ensure the highest energy efficiency. It calculates the velocity pressure based on the air density and the velocity of the air flowing through the duct, providing accurate and practical insights for designing efficient ventilation systems. It is for following chemical composition: For flue gas flow rate measurement specifically, we offer a range of flow meters, which calculate flow measurements in ducts, outlets and filters. Inside the boiler pressure is due to combustion products (Flue gas) & outside pressure is due to fresh atmospheric air. An HVAC calculator is a specialized tool designed to simplify complex heating, ventilation, and air conditioning (HVAC) calculations across various areas such as load estimation, duct sizing, energy efficiency, and airflow dynamics. Eclipse has a proven methodology Nov 17, 2008 · Gas Water Heater and Furnace Chimney Flue Size Calculations The basic method for the chimney flue size calculations is "The Seven Times Rule" (applies to natural draft and / or fan assisted type appliances vented into the same chimney). Determine round or rectangular duct dimensions based on airflow. Oct 17, 2014 · Related Documents Chimney Sizing Calculate chimney draft and required chimney area - online calculator. Noise Rating (NR) curves. Not doing so will likely lead to an expensive duct stiffening arrangement, excessive duct support-structure loads, and/or flow characteristics that don't meet specification or entrain and deposit undesired particulate. 1 inches based on these inputs and factors like air density and available back pressure Economizer heating surface and Its Outlet Flue Gas Temperature Calculation in thermal power plants with online calculator. Oct 17, 2014 · The Darcy-Weisbach equation can be used to calculate the major pressure and head loss due to friction in ducts, pipes or tubes. comprising the installation. Mecaflux, The software allows the calculation of the thermal flow, and the size of duct flue but for those who do not have the software, here is the calculation method used for the evaluation of the diameter of flues, heat flow duct, and flue gas flow rate, depending on power, on the type of boiler and its performance. [1] In the United States, they are also known as vents for boilers and as breeching for Ductulator (HVAC Tools) Ductulator - Is a calculator used for sizing supply and retur duct systems using the equal friction design method. But larger ducts also result in less resistance, which means we may get too much air flow in that run. Free online ductulator for sizing of HVAC ducts. One of the key formulas used in duct sizing is A = Q / V, where A is the Connector Rise The immediate vertical height from the flue collar to the first turn (connector rise) will have an important effect on the proper functioning of a venting system. HVAC duct size calculator for air conditioning and heating systems that usually require some form of duct system to channel air to places where the conditioned air is needed. Materials thickness and expansion joints are also specified. 16 hours ago · Accurate HVAC duct sizing calculator for airflow, velocity, and pressure drop. This info sheet is a guide and discusses the issues to be addressed when installing a generator set’s exhaust system. Acoustics Room acoustics and acoustic properties. Calculate and compare HVAC duct sizes with our easy-to-use duct size calculator. The exhaust vent system must be pitched back toward the unit by a minimum of 1/4 inch per foot (21 mm per m) of duct length to enable condensate to drain back to the unit for disposal. 2) Ducts must be designed to withstand wind loads, fly ash loads, and velocity limits. PRO's duct calculator will help you estimate the required duct size of the ventilation system for quality air exchange in the room. 76-59. Discover durable flue gas duct components with our expert design, manufacture, and installation services. Historically the term flue meant the chimney itself. ft min 450 DEG C , So from three DGS Problem The fue is a large, rectangular duct with gas temperatures that are very high temperature, up to 752 °F [400 °C]. If you test an existing cyclone, determine the different ratios for the actual equipment you are evaluating. 87 m3/sec. The volume of flue gas in the chimney can be calculated using the following equation: Qc = Qf DCF In most applications, the area of the chimney will fall between 1/10th and 1/12th of the fireplace frontal area. If it is easier (less resistance) for the flue products to spill out the draft hood relief opening than Apr 11, 2025 · Easily estimate the noise levels generated by air moving through HVAC ducts using this Duct Noise Calculator. HVAC Systems Design and sizing of Heating, Ventilation and Air Conditioning systems. HVAC – HOW TO SIZE AND DESIGN DUCTS Air flow problems have plagued the HVAC industry for years. Explain how each of the following flue gas properties affects ESP performance: Gas flow rate Temperature Moisture content Chemical properties (dew point, corrosiveness, and combustibility) Identify important design considerations for discharge electrodes, collection electrodes, and hopper and discharge devices Nov 2, 2018 · This excel sheet is for HVAC duct measurement like duct weight, duct area and all calculation related to ductwork like hanger supports and duct insulation. It involves determining the appropriate dimensions of the ductwork to ensure efficient and effective airflow. Cleaver-Brooks offers two types of Standard Economizers - CCE (Cylindrical) and CRE (Rectangular) units. well-designed ductwork These charts relate duct friction, duct size, air flow in cubic foot per minute and flow velocity. To use a chimney draft calculator, you will need to know the height of your chimney, the flowrate of flue gs, temperature of the flue gas at the inlet of the chimney, and the ambient temperature. No matter how much money you spend on a high-quality HVAC system, the equipment won’t work at its best without properly designed and installed ductwork. You can enter the ducts starting from the fan and working down towards a selected terminal, with Duct Fitting Calculator you can calculate the pressure loss for more than 200 fittings as per ASHRAE standard. The spreadsheet is for duct sheet metal quantity estimation. A spray dryer is typically shaped Ls = The length of straight horizontal pipe right after the last collector pipe closest to the common flue gas exit channel (mm) Dhor = The outer diameter of the horizontal flue gas collector (mm). Oct 17, 2014 · Flow velocity in air ducts should be kept within certain limits to avoid noise and unacceptable friction loss and energy consumption. The capacity of a chimney depends on the potential chimney draft - the pressure difference created by the inside and outside air temperature difference and chimney height - and the chimney area. Explanation Calculation Example: Duct sizing is an important aspect of HVAC design. For aneffective reheat system, the flue gas must be reheated sufficiently so that the resulting duct or liner wall temperature is above the dewpoint temperature of the flue gas. Oct 3, 2024 · This is especially important in large buildings or specialized structures where improper duct sizing or weight estimations can lead to increased costs, installation issues, or even structural damage. A simple solution is to provide room and access to the outdoor air duct for adding temporary air treatment filters or other devices, or a sufficient length of duct so that such equipment could be added when needed. Combustion of fuel release flue gases which is a mixture of Carbon Dioxide, Carbon Monoxide, Sulfur Dioxide, H2O Vapor, Nitrogen or Nitro-Oxides, Oxygen, and ash particles. It calculates the required chimney height and diameter based on the flue gas flow rate and temperature. Jan 7, 2003 · What are the design standards that govern the design of flues and ducts that connect to boilers? Particularly for the power generation industry (primary air ducts, forced draft duct, induced draft ducts, secondary draft ducts, economizer outlet flues etc. The ambient installation location is outdoors and continuously dusty. Oct 17, 2014 · Customize sections, airflows, duct sizes and minor dynamic loss coefficients - add pressure loss paths and evaluate and reconfigure the system to fit your criteria. Fireplace Flue Size Specifications Relation of fireplace size to flue opening dimensions, Table of required chimney flue size and flue dimensions for masonry fireplaces. ) Duct sizing, Duct size, Static pressure. Industrial flue gas ducts and stacks are recurrent object of combined Computational Fluid Dynamic (CFD) and Finite Element (FEM) Analyses aimed to: Improvement of flow performance in order to obtain an optimal temperature and velocities distribution. Sep 25, 2017 · Category IV, being a gas appliance that operates with a positive vent (fan forced vent) connector with a flue gas pressure and temperature less than 140°F (60°C) above its dew point. Intake louvers and outdoor air ducts also require more frequent inspections and cleaning when construc-tion occurs nearby. Oct 17, 2014 · Ducts Sizing - the Velocity Reduction Method The velocity reduction method can be used when sizing air ducts. The flue's size plays a crucial role in ensuring proper draft and efficient operation of your fireplace. Types and materials of chimneys. Jan 9, 2021 · 18-Air & Flue gas ducts sizing: In order to avoid pressure drops in ducting proper sized ducts have to be considered. Jun 19, 2024 · Popularity: ⭐⭐⭐ Duct Sizing Calculation This calculator provides the calculation of duct sizing for HVAC applications. Doubling the duct diameter reduces the friction loss by factor 32. Oct 17, 2014 · Calculate chimney draft and required chimney area - online calculator. Jun 3, 2025 · Our Ductwork Calculator, which some call a ductulator, gives accurate results for duct sizing diameter when the right information is plugged into it. Automate sizing, layout, and reporting to create accurate designs in less time. Enter Single Duct Conditions Below:PROJECT DATA: Job Number: Client: Date: Line Number: Fluid: Oct 17, 2014 · Standard size of circular ventilation air ducts. Aug 16, 2016 · Your chimney's flue size could cause of your drafting issues. Eclipse can provide better industrial duct designs because our engineers consider flow characteristics and structural integrity simultaneously. steel pipe sizing for potable water or sheet metal air duct sizing for room air. However, non-professionals Oct 2, 2010 · HOW CAN WE CALCULATE THE EXHAUST FLUE PIPE DUCT We have 3 MW X 3 Diesel Gensets , the Exhaust from each Diesel Genset DG is 19,492 kg hr 23410 cu. Optimize duct dimensions for efficient heating and cooling systems. A cone is required at the top to increase velocity and achieve effluent dispersal. Jun 28, 2020 · To supply the combustion air required for proper combustion To evacuate the combustion products from the furnace or combustion chamber To evacuate the combustion products to the atmosphere So draught is the pressure difference between the inside the boiler and outside air. Sound transmission through walls. One of the important areas of consideration is the pressure drop of the flue gas as it flows over the tube bundles. The minimum internal pipe diameter required is calculated as 207 mm or 8. KALK. It offers detailed technical data and calculations for various fields such as fluid mechanics, material properties, HVAC systems, electrical engineering, and more. The CFR boiler always delivers dry flue gas for safe exhaust into Category I venting. Simple, fast, and accurate tools for HVAC, electrical, and unit conversions. In this paper, the author is investigating the effect of baffles (guide plates) at bend locations in the flue gas path to streamline the flue gas flow and reduce pressure drop. It gives values of some physical properties - density and viscosity in relation to the temperature of gases. We include excerpts from UMC tables along with additional commentary to assist in sizing metal or masonry chimneys according to chimney diameter, height, materials, and the input BTUH of the appliance Adicot offers free online engineering calculators. Mar 26, 2024 · HVAC ducts are sized based on the required airflow. A previously tried single-point fow meter was inaccurate. Some people like to use round ducts while others use rectangular ducts. Learn how to calculate duct size effectively with h2x's comprehensive guide. Draft calculations show a net chimney effect Fluid Flow Blower & Fan Calculation Blower & Fan generate pressure to move Air (or Gases) for ventilation and industrial process requirements. Oct 17, 2014 · Acoustic noise calculation procedure HVAC systems. Aug 25, 2023 · The Chimney Liner and Flue Pipe Length Calculator provides recommendations for the appropriate length for chimney, stove pipes and Class A chimney pipes. decibel A, B and C calculations. Feb 24, 2023 · If you’re looking to improve the efficiency and performance of your HVAC system, you need to ensure that your ductwork is properly sized. There are two major dry processes: “dry injection” systems inject dry hydrated lime into the flue gas duct and “spray dryers” inject an atomized lime slurry into a separate vessel. Enter duct size, airflow, pressure, and other factors to calculate regenerated noise, breakout noise, and final noise levels after attenuation. air velocity calculator Low and Medium Pressure Loss Ducts Maximum friction rate 0. Optimise airflow and efficiency within your HVAC systems! Oct 17, 2014 · Head loss or major loss in air ducts - equations and online calculator for rectangular and circular ducts - Imperial and SI units. To use this calculator, you typically input values like room dimensions, insulation levels, desired temperature, humidity, or other relevant variables depending on The document provides information for sizing an exhaust pipe for a 635 KVA generator, including input parameters such as straight pipe length, number of elbows, and gas temperature and flow, as well as the calculation formulas used. A furnace duct size calculator can help you determine the right size for your ductwork, so your heating and cooling systems can work more efficiently. The inner dimensions of lined duct or the metal inner liner dimensions of double-wall duct, are the nominal duct size dimensions that are used to determine the cross-sectional area for airflow calculations. Calculate the correct chimney flue size for your fireplace. An undersized flue can lead to smoke backdraft, creosote buildup, and even fire… Read More » Jun 9, 2025 · Leave duct size calculations and installations to pros, but you can still use this duct sizing chart to understand the project better. ) ASHRAE has a graph for estimating flue gas temperature losses in a connector. How to correctly make the calculation of the height and cross section of the chimney for the boiler room. VAV Systems. Users can size Flex, Ductboard, Metal, or Fabric Ducts based on Velocity, Friction loss, or Duct Dimensions. Get accurate dimensions based on fireplace size, type, and professional guidelines. The performance table below enables selection of the correct dilution fan based on the flow rate requirement and the fans ability to overcome duct system resistance. Dual-Duct VAV Systems Chimney & flue sizing tables by type, BTUH, building codes, and other factor: This article series describes the size requirements for chimney flues for different categories of heating appliances. Low spots in the vent must be avoided to prevent the condensate from Flue gases properties table density, specific heat, viscosity This table is for flue gases. Find the best duct dimensions for your HVAC system. What is the purpose of this calculator? This calculator helps determine the area of a duct based on its size, useful in HVAC and duct design. 3) Dampers must be designed to regulate airflow and withstand operating temperatures, with limit switches and linkages to ensure Sep 6, 2025 · The Duct Pressure Drop Calculator is a valuable tool for estimating the pressure drop in HVAC ducts. The flue gas system includes 2 booster fans, 2 bypass dampers, 2 dampers at FGD inlet, 2 dampers at booster fan inlet, 2 dampers at booster fan outlet, 1 damper at FGD common duct and corresponding sealing air fan, flue gas duct, expansion joint, etc. Abstract Prepared by the Air and Gas Duct Structural Design Committee of the Energy Division of ASCE Structural Design of Air and Gas Ducts for Power Stations and Industrial Boiler Applications, Second Edition, assists structural engineers in the layout and performance of the structural analysis and design of air and flue gas ductwork for natural gas, coal, oil, reciprocating internal Flue Gas Composition Calculator Flue Gas Composition Calculator Flue gases are formed on the combustion of air with fuel in the presence of heat. The fue gas could be dirty. 2 Calculate the cyclone dimensions If you design a new cyclone, chose one of the standard geometry in table 1 and assume a diameter D. So, how do you calculate the size of round ducts and rectangular ducts? Normally, engineers use simple software or a ductulator (provided by suppliers) to determine the size of a duct. Low velocity design is very important for the energy efficiency of the air distribution system. Guide for how to design a ductwork system. Flue gas pressure drop is very important for considering heat transfer at APH, Economiser, Bank zone & Super heaters. Dual-Path Units. Abstract Prepared by the Air and Gas Duct Structural Design Committee of the Energy Division of ASCE Structural Design of Air and Gas Ducts for Power Stations and Industrial Boiler Applications, Second Edition, assists structural engineers in the layout and performance of the structural analysis and design of air and flue gas ductwork for natural gas, coal, oil, reciprocating internal Jan 26, 2022 · What Is a Dry Scrubber? In dry scrubbing, lime is injected directly into flue gas to remove SO2 and HCl. Then, the theoretical draft should be determined (depends on buoyancy force) which is a function of chimney height and flue gas temperature. This is not outlet temperature from the appliance, and can vary from such (outlet) temperature by quite a bit, depending upon type of connectors (single wall / insulated / long / short / etc. Single-path units. We will identify the index run, which is the run with the largest pressure drop, and ensure that dampers are added to balance the system for equal pressure drop across all branches. Undersized ducts can lead to all sorts of airflow problems. Correct installation of the exhaust is also crucial to ensuring full performance of the engine. Easily calculate the optimal duct size with our Duct Sizing Calculator. In this article, we’ll discuss how to properly size your ductwork and troubleshoot common problems. Jun 9, 2017 · When sizing by the friction rate results in too high a velocity, we size by the velocity, which results in a larger duct. What do we do about that? Install balancing dampers. This program was developed under the direction of the Gas Research Institute and applies to a wide variety of gas venting situations. Jul 17, 2023 · Fireplace Flue Size Chart A fireplace flue is a vital component of any fireplace, serving as the pathway for smoke and combustion gases to safely exit your home. Air Free online duct pressure drop calculator Oct 17, 2014 · Air flow - volume and velocity - due to stack or flue effect caused by indoor hot and outdoor cold temperature difference. 2 meters and a diameter of 2. 2 inches W Temperature Pressure Gas density Gas viscosity The calculation method proposed is reported in [Dirgo] 4. After sizing the ducts, we will calculate the total duct losses and the dynamic losses caused by fittings. 1 - 0. Reference 2 indicates that duct velocities should be about 900 ft/min or less. 8-78. The Engineering ToolBox provides a wide range of free tools, calculators, and information resources aimed at engineers and designers. g. In order for a venting system to prime (for flow up the vent to start), the vent MUST be heated by the flue gases. A well-designed stack chimney helps ensure efficient combustion and prevent the backflow of flue gas into the furnace. Both the maximum and minimum values of capacity for fan-assisted appliances were calculated by Battelle Institute, using their VENT II computer program. 5 mm (H2O)g at the arch (as per API 560 requirements). 1° / - Module of imputation on the working sheet of the designation and the value of the K-factor. Dec 13, 2019 · But I'm wondering if there is any chart or table that is available for diesel fuel and generator exhaust hot gas so that I can use to check the fuel pipe size and the chimney size, same as that we normally do for e. One side uses I-P units, the other side uses SI units. Nov 22, 2021 · Although the circular flue gas duct has many advantages over the rectangular flue gas duct, it was seldom used in domestic large-capacity units in the past due to the limitations of the layout site, the imperfect design rules and supporting calculation methods for the reinforcing ribs of the circular flue gas duct in China and other factors. Optimize your power plant's efficiency with custom flue gas duct solutions. Noise and Attenuation Noise is usually defined as A system designer must consider environmental and performance criteria when sizing and positioning the exhaust system of a generator set. Low estimates of FGT Rise will provide conservative sizing results. Enter the known values for airflow, duct length, duct diameter, and pressure drop into the calculator, leaving one field empty to calculate its value. Technical standards for determining the size of the chimney. It is used to determine the efficiency of the combustion process and to calculate the emissions of pollutants. This concludes our overview of ductwork system design. Once you have this information, you can enter it into the calculator and it will calculate the amount of draft that is needed. Apr 6, 2025 · Easily calculate HVAC duct size and estimate installation cost based on airflow requirements and duct dimensions. These platforms should be located at a chimney height within the range of five times the flue diameter from the flue gas entrance section and three times the diameter from the outlet of the chimney, or as required by local regulations. Deciding on a flow meter depends on the user’s level of expertise and comfort level with advanced technology, as well as whether the product will be used in an industrial or small-scale environment. Jul 15, 2018 · This hvac duct sizing calculator is very simple, and it calculates the duct friction loss value and air velocity inside the duct. If the boiler is equipped with a fourth pass or a waste heat boiler for utilisation of the waste heat in flue gases from a CHP module or a gas turbine, the flue gas system must be Duct Fitting Calculator is a powerful macro-enabled excel sheet that can perform pressure loss calculations for all types shapes of ducts and fittings in both I-P and SI units. To provide adequate draft and safe venting of combustion products the chimney flue for a fireplace has to be adequate in size or cross-sectional area. This document provides calculations for chimney sizing and draft for a boiler system with 1 boiler producing flue gas at a rate of 57. Friction loss. Ducts that are not well designed result in discomfort, high energy costs, bad air quality, and increased noise levels. 2°/ - Data Visualization Module of the pressure loss coefficients according to the duct shape. Flue gas ducts must be made of non-combustible materials and be resistant to the effects of flue gas and heat. Mar 24, 2025 · Calculation Example: The flue gas flow rate is an important parameter in combustion analysis. 06 meters at the top are required. For the more duct formulas download this All HVAC Calculator excel sheet, in this sheet you will find all calculations of central air conditioning. . 1) The document specifies design, material, and construction requirements for air and flue gas ducts and dampers. ID Fan Motor Power Calculator: Induced Draft (ID) Fan is used to draw the flue gases from the system generated from the combustion of fuel. This article series provides information about masonry fireplaces h2x simplifies duct design for air and ventilation systems. A seven-flue chimney in a four-storey Georgian house in London, showing alternative methods of sweeping A flue is a pipe, or opening in a chimney for conveying exhaust gases from a fireplace, furnace, water heater, boiler, or generator to the outdoors. Calculate sound pressure, sound intensity and sound attenuation. The program includes 2 procedures placed on customized command bar use to know the value of the coefficient K. Air-handling units. The Stack Chimney Effect occurs due to the difference in air density between the ambient air and the flue gas inside the stack. Overview An Economizer recovers heat from flue gases and uses it to increase boiler feedwater temperatures, prior to entering the boiler. Chimney heights between 70. Includes scales for friction loss per unit length, air volume, air velocity, round duct diameter, and rectangular duct diameters. The volume flow rate provided by the fan will depend on the static pressure imposed by the size and length of flue ducting and the number of bends, louvres etc. The material of the entire steam boiler flue gas system must be suitable for temperatures up to 350°C. icw cpgvwv kju wou0r zakph 4pj c6aneyj jq4f ex6z rhzn1