This calculation Excel program makes it possible to carry out the calculation of the pressure losses on the duct works and air distribution systems. Download Duct Friction Loss Excel Calculator: Fan static head is calculated according to the duct friction loss. the more the value of friction loss is the more the static head of …A major friction loss diagram for air ducts - Imperial units ranging 10 - 100 000 cfm. Air Ducts - Major Friction Head Loss, Online Calculator Head loss or major loss in air ducts - equations and online calculator for rectangular and circular ducts - Imperial and SI units. Air Ducts - Sizing Required duct area vs. air flow. Air Ducts - Velocity ...Duct Sizing Calculator. The duct sizing calculation involves determining the proper ductwork size needed for an HVAC system. The formula used in this calculation is Q=VA, where Q is the airflow rate, V is the air velocity, and A is the area of the duct.K-factor editor for local pressure loss. The program includes 2 procedures placed on customized command bar use to know the value of the coefficient K. 1° / - Module of imputation on the working sheet of the designation and the value of the K-factor. 2°/ - Data Visualization Module of the pressure loss coefficients according to the duct shape.Updated March 25, 2024. Show Your Love: The ductulator calculator is a specialized tool used in the HVAC industry to determine the most efficient duct sizes for air distribution …By multiplying air velocity by the cross section area of a duct, you can determine the air volume flowing past a point in the duct per unit of time. Volume flow is usually measured …K-factor editor for local pressure loss. The program includes 2 procedures placed on customized command bar use to know the value of the coefficient K. 1° / - Module of imputation on the working sheet of the designation and the value of the K-factor. 2°/ - Data Visualization Module of the pressure loss coefficients according to the duct shape.Download HVAC Duct Quantities, Weight and Area Calculation Sheets. Air Duct quantity can be estimated in sq. meters or kilograms. These excel sheets will enable you to calculate or estimate the duct weight or the duct surface area.Highlights. Your air ducts deliver cool and hot air throughout your home. There are sheet metal, fiberglass-lined, fiberboard, and flexible ducts. Some signs you need a cleaning include dirty vents and a pest infestation. Air duct cleaning costs $380 on average and ranges between $270 to $490.By knowing how to calculate static pressure in air duct systems, you can determine that the right push of air counteracts the resistance in airflow. In a static pressure calculation, we are looking for the push of air to exceed the resistance. Otherwise, the system won't be able to circulate air throughout the ducts.Now, to properly calculate the return grille size, we have to make these two assumptions: Face velocity is 500 FPM (feet per minute). This is the speed at which the return grille sucks the air from your house into your ducts. Free grille area is 70%. As we know, the grille is always bigger than the duct through which the airflow flows.About Press Copyright Contact us Creators Advertise Developers Terms Privacy Policy & Safety How YouTube works Test new features NFL Sunday Ticket Press Copyright ...The equal friction method for sizing air ducts is often preferred because it is quite easy to use. The method can be summarized to. Compute the necessary air volume flow (m 3 /s, cfm) in every room and branch of the system; Use 1) to compute the total air volume (m 3 /s, cfm) in the main system; Determine the maximum acceptable airflow velocity in the …Duct thickness. Refers to the thickness of the goods on the actual duct. Duct density. Refers to the density of the material from which the duct is made. Duct weight. Refers to the weight of the current duct per meter. Media density. Refers to the density of the medium flowing through the actual duct. Set to air in the initial position. Media ...Air Duct Calculator/Ductulator with Sleeve. 4.2 out of 5 stars. 18. $15.60 $ 15. 60. FREE delivery Apr 29 - May 2 . Add to cart-Remove. Trane Ductulator and Charging Calculator Kit - Trane Flex Ductulator with Sleeve, Metal Ductulator, R-22 Charging Calculator, R410A Charging Calculator. QUICK-GUIDE. Select the duct material from the drop-down list (most duct sizing tools are typically based on galvanised steel ducting by default) Enter the air flowrate in cubic feet per minute (CFM) Enter an internal duct size in inches (this must be limited to a maximum aspect ratio of 5:1 for the results to be valid) The resulting velocity ... This tool will calculate the velocity in any units from the specified volumetric flow rate of a substance flowing through a rectangular duct of a defined width and height. For each new calculation a unique conversion scale will be generated for the range of volumetric flow rates and flow speeds for the length and width specified. FormulaQuickly find the duct diameter best suited to your needs, based on the desired air flow rate and the air velocity in the network. The tool will give you the diameter best suited to your … FPM. Max. Static Loss/100ft: InWg. Free online ductulator for sizing of HVAC ducts. Aug 26, 2023 · About this app. This app is developed to Calculate Duct Size Required with available CFM & FPM. This app calculate Both Rectangular and Round Duct Sizes in Inches. This App is also Calculate Air Flow rate in CFM and this app is also calculate in Air Velocity in FPM. The application is designed for engineers HVAC working in the field of design ... Ductulator - Hand held rotating calculator used for sizing supply and return duct systems using the equal friction design method. Includes scales for friction loss per unit length, air volume, air velocity, round duct diameter, and rectangular duct diameters. One side uses English units, the other side uses Metric units. Air Duct Calculator. Double-sided. Side 1 = standard ducloator with calculations for both round and rectangular duct. Side 2 = Continental vs competitive cross reference for some common GRDs and a Grille sizing chart. Qty 25/package.These calculators estimate the temperature drop (or rise) of air flowing in a duct or fluid flowing in a pipe. An example is the use of insulation to minimize temperature change (either temperature drop or rise) of a process fluid from one location to another(e.g. a hot fluid flowing down a pipe). Temperature Drop Calculator for Air DuctsAir Ducts - Cross Sectional Areas; Example - Generated Noise in Duct by Air Flow. The cross section area of a 200 mm duct can be calculated as. A = π ((0.2 m) / 2) 2) = 0.0314 m 2 The noise generated in the duct with an air flow velocity 10 m/s can be calculated as. L N = 10 + 50 log (10 m/s) + 10 log (0.0314 m 2) = 45 db The noise generated in the same …The Ductulator - Duct Sizing Calculator is a hand held rotating calculator used for sizing supply and return duct systems using the equal friction design method. Includes scales for friction loss per unit length, air volume, air velocity, round duct diameter, and rectangular duct diameters. One side uses English units, the other side uses ...Duct and vent cleaning costs $25 to $45 per vent or $0.15 to $0.25 per square foot. Air duct sanitizing costs $70 to $150 more to prevent mold growth. An air duct inspection costs $80 to $180. Cleaning the HVAC system costs $60 to $370 more for a furnace or AC unit. Air duct cleaning cost - chart.By knowing how to calculate static pressure in air duct systems, you can determine that the right push of air counteracts the resistance in airflow. In a static pressure calculation, we are looking for the push of air to exceed the resistance. Otherwise, the system won't be able to circulate air throughout the ducts.An Air duct pressure drop calculation is essential for designing and operating HVAC (Heating, Ventilation, and Air Conditioning) systems. Understanding how to calculate pressure drops in air ducts allows mechanical engineers to design more efficient and effective systems, ensuring optimal airflow and comfort in residential and commercial … Rectangular duct is rounded up to the nearest 1/4 inch. Calculations are for 60°F dry air at sea level, from 5 to 3000 cfm (approximately standard air which is 0.075lb da /ft³). If "ASHRAE 2013" is selected, Flexible roughness is 0.003 ft when straight and fully stretched tight at 0% compression (adjusted at other compressions), otherwise the ... This calculation Excel program makes it possible to carry out the calculation of the pressure losses on the duct works and air distribution systems. Download Duct Friction Loss Excel Calculator: Fan static head is calculated according to the duct friction loss. the more the value of friction loss is the more the static head of … While air duct cleaning and repair lengthens its life span, ductwork typically needs major replacement every 15 years to work properly. The national average cost for full ductwork replacement is $1,450–$8,000; however, the cost can range anywhere from $250–$12,000 depending on home size, system accessibility, and materials used. The equivalent diameter of a rectangular tube or duct can be calculated as (Huebscher) de = 1.30 (a b)0.625/ (a + b)0.25(1) where. de = equivalent diameter (mm, inches) a= length of major or minor side (mm, inches) b= length of minor or major side (mm, inches) Hydraulic diameter - the "characteristic length" used to calculate the dimensionless ...A major friction loss diagram for air ducts - Imperial units ranging 10 - 100 000 cfm. Air Ducts - Major Friction Head Loss, Online Calculator Head loss or major loss in air ducts - equations and online calculator for rectangular and circular ducts - Imperial and SI units. Air Ducts - Sizing Required duct area vs. air flow. Air Ducts - Velocity ...HVAC Ductwork Sizing Calculator. On this page: How to size your HVAC ductwork? Understanding measurement units for ducts. Using Modernize's HVAC and …Mar 25, 2024 · The ductulator calculator is a specialized tool used in the HVAC industry to determine the most efficient duct sizes for air distribution within a space. It helps calculate the perfect balance between duct size, air velocity, and airflow, ensuring the HVAC system operates at peak efficiency. This balance is crucial for maintaining comfortable ... The Duct Pressure Loss Calculator is an essential tool used to estimate the pressure drop or loss that occurs within a duct system due to various factors such as friction, length, diameter, velocity of airflow, and gravity. Its primary function is to calculate the pressure loss (ΔP) occurring in the duct, offering insights into the system’s efficiency.Duct type: Metal Ductboard Flex Size by: Friction rate Velocity Friction Rate: per 100 ft. in/wg Duct TEL : ft. * include fittings in the Duct TEL Enter either: CFM: or Duct Size: …Example of big metal round and rectangular ducts (3,000+ CFM airflow). To figure out exactly how big ducts you need for central air conditioning systems, we have prepared complete CFM duct charts for all different kinds of ducts:. Duct sizing chart for flex ducts (round ducts with 5-20 inch diameter).; Duct sizing chart for metal ducts (round ducts …An HVAC duct calculator or ductulator is a tool that can be used to calculate the ideal size of your HVAC ducts. It factors in the area size and temperature, air flow velocity, friction loss, and static pressure of the HVAC system.DUCTULATOR. Sizing air ducts is essential task for HVAC Engineers, it requires quick tool to aid HVAC designer to determine air duct dimensions while drafting AC layouts. DUCTULATOR Software, uses two methods to size air ducts based on velocity or static regain method, taking into account the air properties at given temperature and elevation ...Aug 21, 2023 · Cleaning helps not only remove them, but may also remove blockages that can help make your system run more efficiently. Keep reading to learn more about the cost of duct cleaning services. 2024 Duct Cleaning Costs. Calculate local project costs by entering your zip code. Typical Price Range. $ 450 - $ 1,000. An HVAC duct calculator or ductulator is a tool that can be used to calculate the ideal size of your HVAC ducts. It factors in the area size and temperature, air flow velocity, friction loss, and static pressure of the HVAC system.How Much Does an HVAC Replacement Cost in 2024? Average Cost Range: $6,465 - $11,877. Use the calculator below for a more accurate local estimate. Use Modernize's 2024 cost calculator to get accurate HVAC replacement cost. Get local price ranges by zipcode for cooling, heating or both!Now, to properly calculate the return grille size, we have to make these two assumptions: Face velocity is 500 FPM (feet per minute). This is the speed at which the return grille sucks the air from your house into your ducts. Free grille area is 70%. As we know, the grille is always bigger than the duct through which the airflow flows.The Ultimate HVAC Duct Calculator Guide: Increase Efficiency and Improve Airflow. HVAC duct calculators play an essential role in determining the proper size of ductwork for heating, ventilation, and air conditioning systems. Properly sized ducts are critical to maintaining optimum airflow, improving energy efficiency, and ensuring the …By knowing how to calculate static pressure in air duct systems, you can determine that the right push of air counteracts the resistance in airflow. In a static pressure calculation, we are looking for the push of air to exceed the resistance. Otherwise, the system won't be able to circulate air throughout the ducts.ρ = 999.7 kg/m³. Find the dynamic viscosity: µ = 0.001308 kg/ (m · s) Compute the product of the density of water, the velocity of the flow, and L: ρ × u × L = 249.925 (m · s)/kg. Divide the result by the dynamic viscosity to find the Reynolds number: ReD = 249.925/0.001308 = 191,074 The flow is likely turbulent.This calculator allows for calculating the mixed air temperature of a third air source. An example of a third air stream is a Bypass air duct that goes from the supply air plenum back to the return air plenum. Trane has an excellent Engineers Newsletter describing Dehumidify with Constant-Volume Systems.Mar 25, 2024 · The ductulator calculator is a specialized tool used in the HVAC industry to determine the most efficient duct sizes for air distribution within a space. It helps calculate the perfect balance between duct size, air velocity, and airflow, ensuring the HVAC system operates at peak efficiency. This balance is crucial for maintaining comfortable ... Rectangular sheet metal duct = .07" on most metal duct calculators. 2900. 40x12. 100 31/2 x14 2200 38x10 220 31/2 x30 2350 40x10. Rectangular sheet metal duct = .07" on most metal duct calculators. 3050. 42x12. Sep 30, 2023 · Duct load calculation involves determining the heating or cooling load that a duct system must handle. It includes factors like air temperature, humidity, and the area being served. The calculation is complex and is typically done using specialized software. Return air duct size for 1-5 ton ACs is 14” to 22” for round ducts and 13”x12” to 32”x12” for rectangular ducts. Use the return air duct size calculator below for accurate dimensions required for your air conditioner or heat pump. There is also a table of return air duct sizes for round and rectangular ducts for ACs from 1.5 to 5 tons.Now, we can use the previous equation to calculate the makeup air rate for kitchens and dryers under these conditions. (1) 400 – 190 = 210 CFM of makeup air (2) 200 – 190 = 10 CFM of makeup air. Makeup Air Duct Size. Below is a table of the average air inflow rates through different size ducts at different air pressures:Example - Calculate Reynolds Number. A Newtonian fluid with a dynamic or absolute viscosity of 0.38 Ns/m 2 and a specific gravity of 0.91 flows through a 25 mm diameter pipe with a velocity of 2.6 m/s .. Density can be calculated from the specific gravity of the fluid and the density of the specific gravity reference water 1000 kg/m 3 - as. ρ = 0.91 (1000 …Enter the air volume in CFM [l/s]. Select an input criteria and enter its value. Optional: Enter a constraining rectangular duct dimension in inches [cm] Click the Calculate button. …Duct calculator. Air and liquid duct; Calculate duct flow resistance, environmental heat exchange, and adiabatic; Note: outer coefficient of heat transfer usually is 3~10, >10 when winds. Download & Buy. For windows, without network and browser limits.The Duct Area Calculator is a powerful tool designed to help individuals and professionals in the HVAC industry determine the cross-sectional area of rectangular and circular ducts. This essential calculation aids in optimizing airflow, ensuring efficient ventilation systems, and maintaining optimal indoor air quality.Air Flow Conversion Calculator. CUI Devices' air flow conversion calculator can be used to convert between common units for volume air flow and air velocity flowing past a point in a specified area of duct. To use the calculator, enter your air velocity or volume air flow and duct area/type, select your units, click calculate air flow, and your ...Mar 25, 2024 · The ductulator calculator is a specialized tool used in the HVAC industry to determine the most efficient duct sizes for air distribution within a space. It helps calculate the perfect balance between duct size, air velocity, and airflow, ensuring the HVAC system operates at peak efficiency. This balance is crucial for maintaining comfortable ... JP Lamborn Co. ( JPL ) began producing flexible air ducts in 1961. Today the company operates four state-of-the-art manufacturing facilities and is the largest family-owned flexible air duct manufacturer in North America. JPL’s core values of manufacturing high-quality products, providing excellent service, innovation, and strong business ...Free HVAC Duct Sizing - in SI/Metric or US/Imperial units. Welcome to CalcuDUCT - the quick and easy way to size ducts for any HVAC application.The equal friction method for sizing air ducts is often preferred because it is quite easy to use. The method can be summarized to. Compute the necessary air volume flow (m 3 /s, cfm) in every room and branch of the system; Use 1) to compute the total air volume (m 3 /s, cfm) in the main system; Determine the maximum acceptable airflow velocity in the …Air Duct Calculator -Slide Rule Style. This rectangular air duct calculator is the technicians favorite. Provides the following information with one setting:- Friction- Velocity- Round Duct Size- Surface Area...and more. Size: 4" x 8.5". ISBN No. 9781622709823Sturdy construction of heavyweight calculator board with 6 metal eyelets.The Ultimate HVAC Duct Calculator Guide: Increase Efficiency and Improve Airflow. HVAC duct calculators play an essential role in determining the proper size of ductwork for heating, ventilation, and air conditioning systems. Properly sized ducts are critical to maintaining optimum airflow, improving energy efficiency, and ensuring the … A major friction loss diagram for air ducts - SI units. Air Ducts - Friction Loss Diagram A major friction loss diagram for air ducts - Imperial units ranging 10 - 100 000 cfm. Air Ducts - Velocity Diagram Air flow volume, duct size, velocity and dynamic pressure. Circular Ducts - Dimensions Standard size of circular ventilation air ducts. Duct ... Duct Sizer ( Ductulator) for HVAC air ducts. It is designed for calculating and sizing duct dimensions according to air volume CFM, roughness, velocity, etc. It is available in SI and British IP units. Duct sizing needs a ductulator or software but this excel calculator performs the same calculations.October 9, 2023 by GEGCalculators. The size of a return air duct should generally be based on the HVAC system’s capacity. A common rule of thumb is to aim for approximately 400-450 CFM (cubic feet per minute) of airflow per ton of HVAC capacity. For example, a 2-ton system might require a return duct with a size of around 16 inches in diameter.The Duct Size Calculator is a quick reference tool for approximating duct size and equivalent sizes of sheet-metal duct and flexible duct. A new duct-sizing calculator from ASHRAE and the Air Distribution Institute (ADI) allows HVAC air-distribution-system designers to size ducts more accurately, especially flex ducts under … Adjustable Absolute Duct Roughness. If selected, Flexible roughness is 0.003 ft when. straight and fully stretched tight at 0% compression. (adjusted at other compressions), otherwise the. original method of constant 0.01 ft roughness is used. Use ASH RAE 2013 Flex Compression. Formula. The formula for air duct sizing involves the calculation of air velocity (V) and duct cross-sectional area (A) to determine the air volume flow rate (Q), expressed in cubic feet per minute (CFM). Q = A × V. This equation comes from the principle of continuity in fluid mechanics which states that for incompressible flow, the product of ...In April 2024 the cost to Install a Duct starts at $12.13 - $21.39 per linear foot. Use our Cost Calculator for cost estimate examples customized to the location, size and options of your project.. To estimate costs for your project: 1. Set Project Zip Code Enter the Zip Code for the location where labor is hired and materials purchased.. 2.A duct size calculator, commonly known as a ductulator, depends on factors like the size of the space you’re heating or cooling, air flow …Similar Apps to Air Duct Calculator IWA 42 006. The Air Duct Calculator App shows a slide chart that affords the configuration of rectangular, circular and oval air ducts in a minimum of time ...Duct type: Metal Ductboard Flex Size by: Friction rate Velocity Friction Rate: per 100 ft. in/wg Duct TEL : ft. * include fittings in the Duct TEL Enter either: CFM: or Duct Size: …2. Calculator of different ventilation parameters, with which will be able to obtain the diameter, the air speed, the airflow and the dynamic pressure of your installation. 3. Pressure drop calculation tool for installations with …Online Head Loss Calculator. The calculator below, which is based on eq. (2) , can be used to calculate the head loss in a duct, pipe or tube.The default values used in the calculator are for air flow 20 o C , 1.2 kg/m 3 and 6 m/s .The default density of water commonly used as reference fluid is 1000 kg/m 3.The friction coefficient is calculated … Ductulator - Hand held rotating calculator used for sizing supply and return duct systems using the equal friction design method. Includes scales for friction loss per unit length, air volume, air velocity, round duct diameter, and rectangular duct diameters. One side uses English units, the other side uses Metric units. Duct calculator. Air and liquid duct; Calculate duct flow resistance, environmental heat exchange, and adiabatic; Note: outer coefficient of heat transfer usually is 3~10, >10 when winds. Download & Buy. For windows, without network and browser limits.Download duct static pressure calculator excel sheet XLS. Free spreadsheet program for air duct friction loss calculation. Download Free MEP Calculation Excel Sheets, AutoCAD Drawings, and Training Courses for HVAC, Firefighting, Plumbing and Electrical Systems Design.
Air Ducts - Cross Sectional Areas; Example - Generated Noise in Duct by Air Flow. The cross section area of a 200 mm duct can be calculated as. A = π ((0.2 m) / 2) 2) = 0.0314 m 2 The noise generated in the duct with an air flow velocity 10 m/s can be calculated as. L N = 10 + 50 log (10 m/s) + 10 log (0.0314 m 2) = 45 db The noise generated in the same …. Capstarbank
Air Duct Calculator -Slide Rule Style. This rectangular air duct calculator is the technicians favorite. Provides the following information with one setting:- Friction- Velocity- Round Duct Size- Surface Area...and more. Size: 4" x 8.5". ISBN No. 9781622709823Sturdy construction of heavyweight calculator board with 6 metal eyelets.To adequately calculate the speed of air in ducts, we have to primarily calculate the cross-section of the duct. Shape-wise, ducts can be: Round. The area of round flex ducts is calculated as π*R 2 where R is the radius of the duct. Example: 10-inch round duct has a radius of 5 inches.Ductulator is an engineering tool to calculate air duct dimensions based on air-flow, duct material, roughness and pressure or velocity. It supports round and rectangular duct options and provides accurate and easy to … Sheet Metal Duct Friction Loss Calculator. 1. Enter Duct Airflow (CFM), Duct Velocity (FPM), Duct Length and the number of bends. 2. Read Round Duct Diameter (inches) and Friction Loss Per 100' of duct (inches of water). 1. Enter Friction Loss Per 100' of duct (inches of water), Duct Airflow (CFM), Duct Length and the number of bends. Precise Calculations: Learn special techniques for superior installation, calculating duct sizes and friction rate. Reduce Hot & Cold Spots: Master duct system balancing to minimize temperature fluctuations. *This class qualifies for 8 hours of NATE continuing education credits. Program Price: $399. Premier Dealers: $319* (20% discount)Apr 25, 2022 · At 350-400 CFM per 12,000 BTUs of heating capacity, there’s enough airflow to circulate heated air through supply ducts and pull cool air back to the furnace or air handler through the cold air returns. A 3-ton unit, or 36,000 BTUs, would need a blower capable of moving 3 x 350-400 CFM, so a total of 1,050 to 1,200 CFM. In April 2024 the cost to Install a Duct starts at $12.13 - $21.39 per linear foot. Use our Cost Calculator for cost estimate examples customized to the location, size and options of your project.. To estimate costs for your project: 1. Set Project Zip Code Enter the Zip Code for the location where labor is hired and materials purchased.. 2.Instructions. (Input information may generally be be obtained from design documents or field measurements) Line 1. Enter the temperature of the air entering the duct. Line 2. Enter the ambient temperature (the average temperature of the air surrounding the duct) Line 3. Enter the flow rate of the air carried by the duct in cubic … Ductulator - Hand held rotating calculator used for sizing supply and return duct systems using the equal friction design method. Includes scales for friction loss per unit length, air volume, air velocity, round duct diameter, and rectangular duct diameters. One side uses English units, the other side uses Metric units. Duct Sizing Calculator. The duct sizing calculation involves determining the proper ductwork size needed for an HVAC system. The formula used in this calculation is Q=VA, where Q is the airflow rate, V is the air velocity, and A is the area of the duct. Formula. The formula for air duct sizing involves the calculation of air velocity (V) and duct cross-sectional area (A) to determine the air volume flow rate (Q), expressed in cubic feet per minute (CFM). Q = A × V. This equation comes from the principle of continuity in fluid mechanics which states that for incompressible flow, the product of ... So, the duct design work is made simpler and easy. Since this is a web-based program, users can log in from any browser using an ID and password. Apart from duct designing, this software also helps in Duct sizing. With DuctQuote, you can. Calculate air flow for duct design; Draws 3D systems; Generate custom quotes using logo and …Air Duct Calculator/Ductulator with Sleeve. 4.2 out of 5 stars. 18. $15.60 $ 15. 60. FREE delivery Apr 29 - May 2 . Add to cart-Remove. Trane Ductulator and Charging Calculator Kit - Trane Flex Ductulator with Sleeve, Metal Ductulator, R-22 Charging Calculator, R410A Charging Calculator.Feb 16, 2023 · Calculate for each individual room. To calculate CFM, you need to know the size of your heating or cooling unit in tons. Multiply this number by 400, which is the average output of an HVAC unit. Then divide by the total square footage of your home. This will give you the multiplier for all your rooms’ CFM. HVAC Ductwork Sizing Calculator. On this page: How to size your HVAC ductwork? Understanding measurement units for ducts. Using Modernize's HVAC and …Friction Loss per 100 Feet = (0.109136 * q 1.9 ) / (d 5.02 )* (l/100) Where, q = Air Volume Flow. d = Equivalent Duct Diameter. l = Duct Length. Online air duct friction loss calculation. Use this simple science air duct friction loss calculator to …Return air duct size for 1-5 ton ACs is 14” to 22” for round ducts and 13”x12” to 32”x12” for rectangular ducts. Use the return air duct size calculator below for accurate dimensions required for your air conditioner or heat pump. There is also a table of return air duct sizes for round and rectangular ducts for ACs from 1.5 to 5 tons.Air duct also termed as ductulator is a passage that is used to provide fresh air into rooms, buildings etc., Air ducts may be in circular, square and in rectangular shapes. This online air duct calculator is used to calculate the velocity of air flow feet per minute (FPM), and feet per second (FPS) through any shaped (circle, square or rectangle) ductulator with …Online Head Loss Calculator. The calculator below, which is based on eq. (2) , can be used to calculate the head loss in a duct, pipe or tube.The default values used in the calculator are for air flow 20 o C , 1.2 kg/m 3 and 6 m/s .The default density of water commonly used as reference fluid is 1000 kg/m 3.The friction coefficient is calculated … Duct Size Calculator. Ductulator is an engineering tool to calculate air duct dimensions based on given inputs including air-flow, duct material roughness and either air pressure static loss (friction method) or air velocity (velocity method). This online ductulator calculates the dimensions for both round and rectangular duct options (one ... .