Fan Tools -

Advanced Fan Efficiency Calculator — Cement Industry

⚙ General Fan Data

SELECT FAN

Fan Type / Equipment

Fan Name / Tag

Fan RPM (Actual)

RPM

Design RPM

RPM

Impeller Diameter

📐 Inlet Duct Shape — Auto Area Calculation

● CIRCULAR ○ RECTANGULAR

Inlet Duct Diameter (DID)

✓ Calculated Inlet Area

— m²

📐 Outlet Duct Shape — Auto Area Calculation

● CIRCULAR ○ RECTANGULAR

Outlet Duct Diameter (DID)

✓ Calculated Outlet Area

— m²

Pitot Tube Constant (Cp)

Damper Position

VFD Frequency

Fan Arrangement

⚡ Motor Power Input

⚡

MODE 1 — Direct kW

I know the Fan kW

🔢

MODE 2 — Calculate kW

From V, I, Power Factor

Fan Shaft Power (kW) ℹ️

Motor Rated kW (nameplate)

Drive Efficiency ℹ️

p.u.

✓ Motor Loading

— %

Fan Power (kW)

—

kW used

Shaft Power

—

Motor Eff.

% (assumed)

🌡 Temperature & Gas Properties

Fan Inlet Gas Temperature ℹ️

°C

Fan Outlet Gas Temperature

°C

Ambient Temperature

°C

Gas Type / Composition ℹ️

Gas Density Calculation Method

🔬 GAS ANALYZER — ACTUAL COMPOSITION INPUT

ℹ How This Method Works (click to expand)

Why Gas Analyzer Values Are Required:
Gas density in cement plant flue gas depends heavily on actual composition — the CO₂ fraction alone can raise density 15–20% above ambient air. Using a gas analyzer gives the real molecular weight of the mixture, which is essential for accurate velocity and flow calculation.

How Density Is Calculated:
1. Molecular weight of mixture: MW = Σ(xᵢ × MWᵢ) where x = mole fraction
O₂(32) + CO₂(44) + CO(28) + N₂(28) — N₂ is auto-filled as balance
2. Standard density: ρ_std = MW × 101325 / (8314 × 273.15)
3. Actual density: ρ_act = MW × P_baro / (8314 × (T + 273.15))

Why This Is More Accurate:
Cement kiln flue gas typically has 18–28% CO₂, raising MW from 29 (air) to ~31–33 g/mol. This method captures that difference precisely, unlike gas-type presets.

O₂ (%)

CO₂ (%)

CO (%)

N₂ (auto-balance)

— %

Calc. MW (g/mol)

—

ρ_std @ 0°C (kg/m³)

—

ρ_actual @ T,P (kg/m³)

—

← used in all calcs

⚡ COMPUTED GAS DENSITY — LIVE

Standard ρ (0°C)

—

kg/m³

Actual ρ at inlet T

—

kg/m³ ← used in calcs

Correction Factor

—

ρ_actual / ρ_std

Method 1: ρ = MW_mix × P / (8314 × T_K) | Method 2: ρ = ρ_std × (273/(273+T)) × (P/101325)

Manual Density Override ℹ️

kg/m³

Standard Gas Density (0°C, 1 atm)

kg/m³

🏔 Altitude / Barometric Correction

Plant Elevation (MSL)

Barometric Pressure (Measured)

Standard Atmosphere Equation
P = 101325 × (1 − 2.25577×10⁻⁵ × h)^5.25588 Pa

Calc. Baro. (Pa)

—

Density Correction

—

factor

Corrected ρ

—

kg/m³

Density Correction Formula
ρ_actual = (P × MW) / (R × T) | R = 8314 J/(kmol·K)
Correction Factor = ρ_actual / ρ_standard

⚙ Fan Inlet Measurement Method

SELECT METHOD

For large fans (RABH, ESP, ID Fans): Direct inlet draft measurement is frequently unreliable due to turbulent flow, non-uniform velocity profiles, and limited straight duct length. Use Option 2 to back-calculate inlet conditions from stack measurements.

OPTION 1 — Direct Inlet Measurement

Measure fan inlet draft and static pressure directly using manometer or pressure transmitter installed on the fan inlet duct. Suitable for fans with adequate straight duct length and stable, measurable flow conditions.

✓ Cooler Fans ✓ Raw Mill Fans ✓ Coal Mill Fans

OPTION 2 — Back-Calculation from Stack Data

When direct inlet measurement is impractical. Enter stack/outlet measurements and the calculator back-traces through system pressure losses to estimate effective fan inlet draft and density conditions.

⚡ RABH Fans ⚡ ESP Fans ⚡ Large ID Fans

🏭 Stack / Outlet Data — Back-Calculation Engine

OPTION 2 ACTIVE

Back-Calculation Methodology:
Inlet Draft = Stack Draft + Σ(System Pressure Losses: duct friction + fittings + equipment) + Elevation Draft (ρ·g·Δh)
Inlet Density = Stack Gas Density corrected for temperature difference between stack and fan inlet.
Calculated values are automatically fed into the fan efficiency computation. Manual override remains available.

🏭 Stack / Outlet Conditions

Stack Gas Temperature

°C

Stack Static Draft / Pressure

mmWC

Stack O₂ Concentration (optional)

Stack Duct Diameter

Gas Flow at Stack (actual)

m³/hr

Stack Gas Mol. Weight

g/mol

📐 System Geometry & Losses

Elevation Difference (Fan → Stack)

+ve = stack is above fan (buoyancy helps draft)

Duct Length (Fan outlet → Stack)

Duct Diameter (Fan outlet duct)

Duct Roughness (ε)

Number of 90° Bends

Number of 45° Bends

⚙ Equipment Pressure Losses

Filter / Bag House ΔP (if downstream)

mmWC

Expansion / Contraction Loss

mmWC

Additional Manual Loss (dampers, etc.)

mmWC

Fan Inlet Gas Temperature

°C

Used to correct density from stack to fan inlet

Barometric Pressure

── BACK-CALCULATED RESULTS ──

Stack Gas Density

—

kg/m³

Stack Gas Velocity

—

m/s

Duct Friction Loss

—

mmWC

Bend Losses

—

mmWC

Elevation Draft

—

mmWC

Total System ΔP

—

mmWC

Est. Fan Inlet Draft ←

—

mmWC (back-calculated)

Est. Fan Inlet Density ←

—

kg/m³ (back-calculated)

📊 Pressure Measurements

OPTION 1 — DIRECT

Fan Inlet Draft (Negative)

mmWC

Fan Outlet Pressure

mmWC

Static Pressure Rise

mmWC

Velocity Pressure (Pitot)

mmWC

Total Pressure (measured)

mmWC

Pressure Unit Display

Conversions

Inlet (Pa)

—

Outlet (Pa)

—

Static ΔP (Pa)

—

Total ΔP (Pa)

—

🔬 Dynamic DP Readings (Pitot Traverse)

Pitot Traverse Method
Multiple VP readings at equal area traverse points. Q = Cp × A × √(2 × VP_avg / ρ)

#	Point	VP Reading (mmWC)	√VP

Min VP

—

mmWC

Max VP

—

mmWC

Avg √VP

—

Avg VP

—

mmWC

💨 Flow Calculation Methods

Method 1: Pitot Traverse

Avg Velocity Pressure (from traverse)

mmWC

Measurement Duct Shape

● CIRCULAR ○ RECTANGULAR

Measurement Duct Diameter

Pitot Coefficient (Cp) ℹ️

⚡ PITOT FLOW RESULT — LIVE

Area (m²)

—

Density (kg/m³)

—

Velocity (m/s)

—

Flow (m³/s)

—

v = Cp × √(2×ΔP_Pa/ρ) | Q = v × A

Method 2: Direct Velocity

Measured Gas Velocity

m/s

DUCT AREA (from inlet setup above): — m²

Flow (Velocity) — Real-time

—

m³/s (actual)

Method 3: Design / NM³ Input

Design Flow (Nm³/hr)

Nm³/hr

Operating Temperature

°C

Barometric Pressure

Actual Flow

—

m³/s (actual)

Flow Summary & Density Correction

Selected Flow Q

—

m³/s

Flow (m³/hr)

—

m³/hr

Density-Corr. Flow

—

Nm³/hr

Gas Velocity

—

m/s

USE THIS FLOW FOR EFFICIENCY CALCULATION

🏭 Process-Specific Parameters

SELECT FAN TYPE FIRST

ℹ Select a fan type in the Fan Configuration tab to see process-specific parameters.

🏭 Common Process Inputs — Entire Cooler Section

GLOBAL PARAMETERS

These values apply to all cooler fans and update all calculations in real time. Clinker Output = (Kiln Feed × 1000) ÷ Clinker Factor.

Kiln Feed

TPH

Clinker Factor ℹ️

ratio

Ambient Temperature

°C

Normal Air Density ρₙ

kg/m³

Actual Air Density ρₐ (override) ℹ️

kg/m³

Clinker Output

— kg/hr

= (KF × 1000) ÷ CF

Actual Air Density

— kg/m³

= ρₙ × 273 ÷ (273 + T)

❄ COOLER FAN CARDS

📊 Overall Cooler Summary — Live Dashboard

REAL-TIME

Fans Active

Total m³/hr

—

actual

Total Nm³/hr

—

normal

Σ Sp. Air (Nm³/kg)

—

Nm³/kg clinker

Σ Sp. Air (kg/kg)

—

kg air/kg clinker

Avg Efficiency

—

Total Motor kW

—

Flow Imbalance

—

Fan	Mode	Velocity (m/s)	Flow (m³/hr)	Flow (Nm³/hr)	Sp. Air (Nm³/kg)	Sp. Air (kg/kg)	Motor kW	Efficiency %	Motor Load %	Status

📈 Fan Laws — Interactive Module

Q₂/Q₁ = N₂/N₁Flow varies linearly with RPM

P₂/P₁ = (N₂/N₁)²Pressure varies as square of RPM

W₂/W₁ = (N₂/N₁)³Power varies as cube of RPM

Design / Reference RPM (N₁)

RPM

Design Flow Q₁

m³/s

Design Pressure P₁

Design Power W₁

Adjust RPM Slider (N₂)

20% 120%

100%

N₂

900

RPM

Q₂

—

m³/s

P₂

—

W₂

—

Power Change

—

Deviation

—

from design

RPM vs FLOW

RPM vs PRESSURE

RPM vs POWER (Cube Law!)

Engineering Insight: A mere 10% increase in RPM increases power by ~33% (1.1³ = 1.331). This is why overspeeding fans leads to motor overloads. VFDs save enormous energy by reducing RPM when full flow is not required — a 20% RPM reduction cuts power by ~49%.

🎯 Fan Efficiency Results

AWAITING INPUT

Fan Efficiency 0%

📐 Calculated Parameters

Flow Q

—

m³/s

Total Pressure ΔP

—

Static Pressure

—

Velocity Pressure

—

Shaft Power

—

Fan Efficiency

—

Specific Power

—

kWh/1000m³

System Resistance

—

mmWC

Gas Velocity

—

m/s

Motor Loading

—

⚖ Fan Law Deviation Analysis

RPM Ratio

—

Expected Flow

—

m³/s

Actual Flow

—

m³/s

Flow Deviation

—

Fan Law Performance Deviation: If actual flow significantly differs from fan law prediction at the same RPM ratio, it indicates system resistance change (dirty filter, damper position, air leakage) or fan mechanical issue (blade wear, inlet vortex).

🔍 Automatic Diagnostics

Run diagnostics after calculating all parameters to get engineering insights.

💡 Plant Recommendations

Recommendations will appear after diagnostics are run.

📏 Instrument Uncertainty & Calibration

Pitot Tube

Calibration Date

Uncertainty

Condition

Pressure Transmitter

Calibration Date

Uncertainty

Condition

Power Meter / CT

Calibration Date

Uncertainty

Overall Measurement

—

📚 Engineering Reference Notes

Static vs Velocity vs Total Pressure
Static Pressure = Energy stored in gas as pressure. Velocity Pressure = Kinetic energy of moving gas. Total Pressure = Static + Velocity. VP = ½ρv². Fans develop Total Pressure; the system converts it into useful static pressure.

Density Correction Importance
Fan flow Q (m³/s) is volumetric — same volume at high temperature has lower mass. For process purposes, Nm³/hr matters. Always correct: Q_actual × (273+T)/(273) × (101325/P_baro) = Q_normal.

Why Altitude Affects Fan Performance
At higher altitude, lower air density means lower mass flow for same volumetric flow. Fan develops same ΔP in Pa but lower mass flow. Motor may seem underloaded but process gas is deficient — always correct to actual operating density.

Pitot Traverse Accuracy
Single-point pitot reading can have ±15% error. Proper traverse (log-Tchebycheff) across 16-20 points at equal area intervals gives ±2% accuracy. Use average of √VP (not √(avg VP)) — this gives true mean velocity.

System Resistance & Fan Efficiency
Fan efficiency alone does not determine system performance. A 90% efficient fan driving through a badly sized system wastes energy. System resistance ∝ Q². If resistance doubles, same fan delivers ~30% less flow. Check duct sizing, bends, and obstructions.

Why Actual Flow Differs from Design
Temperature deviation from design → volumetric flow change. Air infiltration/leakage → extra flow. Worn impeller → lower head and flow. Changed system resistance → new operating point on curve. Incorrect RPM → fan law deviation.

📄 Report Generation

🔐

Admin-Protected: Report preview is free. Printing or downloading requires the admin password. Contact barunsway.com administration for access credentials.

Plant / Unit Name

Equipment Tag

Operator / Engineer

Test Date

Remarks / Observations

barunsway.com · Engineering Tool

— CEMENT PLANT —

Advanced Fan Efficiency Analysis Report

Date: —

Engineer: —

Equipment: —

Report No: —

Fan Efficiency Status:

—

Fan Type: —

1 · Fan Configuration

Parameter	Value	Parameter	Value
Fan Type / Category	—	Fan Name / Tag	—
Actual Running RPM	—	Design RPM	—
Impeller Diameter	—	Fan Arrangement	—
Inlet Duct Area	—	Outlet Duct Area	—
Damper Position	—	VFD Frequency	—
Pitot Tube Constant (Cp)	—	Drive Type	—

2 · Motor & Electrical Data

Parameter	Value	Parameter	Value
Motor Rated kW	—	Motor Efficiency	—
Actual Power Consumed	—	Drive Efficiency	—
Motor Loading	—	Shaft Power	—

barunsway.com — Fan Efficiency Report

— | —

3 · Process & Gas Conditions

Parameter	Value	Parameter	Value
Fan Inlet Temperature	—	Ambient Temperature	—
Barometric Pressure	—	Plant Elevation (MSL)	—
Gas Type / Composition	—	Gas Density Method	—
Standard Gas Density ρₛ	—	Actual Gas Density ρₐ	—

4 · Pressure Measurements

Parameter	Measured Value	Unit	Pa Equivalent	Note
Fan Inlet Draft	—	mmWC	—	Negative = suction side
Fan Outlet Pressure	—	mmWC	—
Static Pressure Rise	—	mmWC	—
Velocity Pressure (Pitot)	—	mmWC	—	Avg of traverse readings
Total Pressure Rise ΔP	—	mmWC	—	Static + Velocity
Measurement Method	—

5 · Gas Flow Measurements

Parameter	Value	Unit	Remarks
Measurement Method	—	—	Selected by engineer
Gas Velocity	—	m/s	At measurement point
Actual Gas Flow Q	—	m³/s	Actual volumetric
Gas Flow (m³/hr)	—	m³/hr
Normal Flow (Nm³/hr)	—	Nm³/hr	Density corrected @ 0°C, 101325 Pa

barunsway.com — Fan Efficiency Report

— | —

6 · Calculated Performance Results

Fan Efficiency

—

Gas Flow

—

m³/s

Shaft Power

—

Motor Load

—

Calculated Parameter	Value	Unit	Assessment
Fan Total Efficiency η	—	%	—
Total Pressure Rise ΔP	—	Pa	Static + Velocity
Static Pressure Rise	—	Pa
Velocity Pressure	—	Pa
Specific Power Consumption	—	kWh/1000m³	Lower is better
System Resistance	—	mmWC	Total duct + equipment loss
Gas Flow Status	—	—

7 · Engineering Assessment & Diagnostics

Generate report after running diagnostics to populate this section.

barunsway.com — Fan Efficiency Report

— | —

8 · Fan Law Deviation Analysis

Parameter	Value	Parameter	Value
RPM Ratio (Actual / Design)	—	Fan Law Expected Flow	—
Actual Measured Flow	—	Flow Deviation	—

Note: Significant deviation from fan law prediction indicates system resistance change (dirty filter, damper adjustment, air leakage) or fan mechanical degradation (blade erosion, inlet vortex, shaft misalignment).

9 · Site Remarks & Observations

—

10 · Authorisation & Sign-off

Prepared By

Name & Signature

Date: ________________

Reviewed By

Name & Signature

Date: ________________

Approved By

Name & Signature

Date: ________________

barunsway.com · Advanced Fan Efficiency Analyzer · Cement Industry Engineering Tool

Generated: — · This report is confidential and proprietary to barunsway.com