{"id":100081,"date":"2026-02-15T20:15:34","date_gmt":"2026-02-15T20:15:34","guid":{"rendered":"https:\/\/vibromera.eu\/?post_type=calculator&#038;p=100081"},"modified":"2026-02-15T20:15:34","modified_gmt":"2026-02-15T20:15:34","slug":"engine-parameters-iso3046","status":"publish","type":"calculator","link":"https:\/\/vibromera.eu\/bn\/calculators\/engine-parameters-iso3046\/","title":{"rendered":"\u0987\u099e\u09cd\u099c\u09bf\u09a8 \u09aa\u09cd\u09af\u09be\u09b0\u09be\u09ae\u09bf\u099f\u09be\u09b0 \u0995\u09cd\u09af\u09be\u09b2\u0995\u09c1\u09b2\u09c7\u099f\u09b0 | ISO 3046 | BSFC, BMEP, \u099f\u09b0\u09cd\u0995 | \u09ac\u09bf\u09a8\u09be\u09ae\u09c2\u09b2\u09cd\u09af\u09c7 \u09b8\u09b0\u099e\u09cd\u099c\u09be\u09ae"},"content":{"rendered":"\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@type\":\"WebApplication\",\"name\":\"Engine Parameters Calculator\",\"alternateName\":[\"ISO 3046 Calculator\",\"BSFC Calculator\",\"BMEP Calculator\"],\"description\":\"Free engine parameters calculator per ISO 3046. 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Typical diesel: 190-230 g\/kWh. Lower BSFC means higher efficiency.\"}},\n{\"@type\":\"Question\",\"name\":\"What is BMEP and why is it important?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Brake Mean Effective Pressure (BMEP) is the average cylinder pressure that would produce the same work output. It normalizes engine performance regardless of displacement. Typical naturally aspirated diesel: 7-10 bar, turbocharged diesel: 15-25 bar.\"}},\n{\"@type\":\"Question\",\"name\":\"What are the ISO 3046 power rating types?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"ISO 3046 defines: COP (Continuous Power) for unlimited hours, PRP (Prime Power) for variable load with unlimited hours, LTP (Limited Time Power) for max 500h\/year, and ESP (Emergency Standby Power) for max 200h\/year at variable load.\"}},\n{\"@type\":\"Question\",\"name\":\"How does altitude affect engine power?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Engine power decreases with altitude due to lower air density. 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}\n    .vc-copy-btn, .vc-section-chevron, .vc-faq-chevron, .vc-presets, .vc-promo { display:none!important; }\n}\n<\/style>\n\n<div class=\"vc-calculator\" id=\"vc-engine-parameters-iso3046\">\n\n<!-- Header -->\n<header class=\"vc-header\">\n    <p class=\"vc-header-eyebrow\">Free Engineering Tool<\/p>\n    <h1 class=\"vc-header-title\">Engine Parameters Calculator<\/h1>\n    <p class=\"vc-header-subtitle\">ISO 3046 engine power rating, BSFC, BMEP, torque, and thermal efficiency. Diesel vs gas engine comparison with derating support.<\/p>\n    <div class=\"vc-badges\">\n        <span class=\"vc-badge\">ISO 3046<\/span>\n        <span class=\"vc-badge\">BSFC<\/span>\n        <span class=\"vc-badge\">BMEP<\/span>\n        <span class=\"vc-badge\">Torque<\/span>\n        <span class=\"vc-badge\">Diesel &amp; Gas<\/span>\n    <\/div>\n<\/header>\n\n<!-- Calculator Card -->\n<div class=\"vc-card\">\n    <div class=\"vc-unit-bar\">\n        <button type=\"button\" class=\"vc-unit-btn vc-active\" data-system=\"metric\">Metric (kW, kg\/h, bar)<\/button>\n        <button type=\"button\" class=\"vc-unit-btn\" data-system=\"imperial\">Imperial (HP, lb\/h, psi)<\/button>\n    <\/div>\n\n    <form class=\"vc-form\" id=\"vc-form\" autocomplete=\"off\">\n        <div class=\"vc-form-grid\">\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-rating\">Power Rating Type<\/label>\n                <select class=\"vc-select\" id=\"vc-rating\">\n                    <option value=\"1.0\" selected>COP \u2014 Continuous Power (1.0\u00d7)<\/option>\n                    <option value=\"1.1\">PRP \u2014 Prime Power (1.1\u00d7)<\/option>\n                    <option value=\"1.2\">LTP \u2014 Limited Time (1.2\u00d7)<\/option>\n                    <option value=\"1.3\">ESP \u2014 Emergency Standby (1.3\u00d7)<\/option>\n                <\/select>\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-ftype\">Fuel Type<\/label>\n                <select class=\"vc-select\" id=\"vc-ftype\">\n                    <option value=\"diesel\" selected>Diesel (CV \u2248 42,700 kJ\/kg)<\/option>\n                    <option value=\"hfo\">HFO (CV \u2248 40,200 kJ\/kg)<\/option>\n                    <option value=\"natgas\">Natural Gas (CV \u2248 50,000 kJ\/kg)<\/option>\n                    <option value=\"lpg\">LPG (CV \u2248 46,000 kJ\/kg)<\/option>\n                    <option value=\"custom\">Custom<\/option>\n                <\/select>\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-fuel\">Fuel Consumption <span class=\"vc-label-hint\" id=\"vc-fuel-hint\">(kg\/h)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-fuel\" inputmode=\"decimal\" step=\"any\" min=\"0\" value=\"50\" placeholder=\"e.g. 50\">\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-cv\">Calorific Value <span class=\"vc-label-hint\">(kJ\/kg)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-cv\" inputmode=\"decimal\" step=\"any\" min=\"0\" value=\"42700\" placeholder=\"e.g. 42700\">\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-eff\">Thermal Efficiency \u03b7 <span class=\"vc-label-hint\">(%)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-eff\" inputmode=\"decimal\" step=\"any\" min=\"0\" max=\"70\" value=\"38\" placeholder=\"e.g. 38\">\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-disp\">Displacement <span class=\"vc-label-hint\">(L)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-disp\" inputmode=\"decimal\" step=\"any\" min=\"0\" value=\"12\" placeholder=\"e.g. 12\">\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-speed\">Engine Speed <span class=\"vc-label-hint\">(RPM)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-speed\" inputmode=\"decimal\" step=\"any\" min=\"0\" value=\"1500\" placeholder=\"e.g. 1500\">\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-stroke\">Stroke Type<\/label>\n                <select class=\"vc-select\" id=\"vc-stroke\">\n                    <option value=\"4\" selected>4-Stroke<\/option>\n                    <option value=\"2\">2-Stroke<\/option>\n                <\/select>\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-afr\">Air\/Fuel Ratio \u03bb <span class=\"vc-label-hint\">(stoich. \u00d7 excess)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-afr\" inputmode=\"decimal\" step=\"any\" min=\"0\" value=\"14.5\" placeholder=\"e.g. 14.5\">\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-ncyl\">Number of Cylinders<\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-ncyl\" inputmode=\"decimal\" step=\"1\" min=\"1\" value=\"6\" placeholder=\"e.g. 6\">\n            <\/div>\n        <\/div>\n\n        <!-- Presets -->\n        <div class=\"vc-presets\">\n            <div class=\"vc-presets-label\">Quick presets<\/div>\n            <button type=\"button\" class=\"vc-preset-btn\" data-fuel=\"25\" data-cv=\"42700\" data-eff=\"36\" data-disp=\"6\" data-spd=\"1800\" data-str=\"4\" data-ft=\"diesel\" data-afr=\"14.5\" data-cyl=\"4\">100 kW Diesel Genset<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-fuel=\"50\" data-cv=\"42700\" data-eff=\"38\" data-disp=\"12\" data-spd=\"1500\" data-str=\"4\" data-ft=\"diesel\" data-afr=\"14.5\" data-cyl=\"6\">200 kW Diesel Industrial<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-fuel=\"150\" data-cv=\"42700\" data-eff=\"42\" data-disp=\"30\" data-spd=\"1000\" data-str=\"4\" data-ft=\"diesel\" data-afr=\"14.5\" data-cyl=\"8\">600 kW Marine Diesel<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-fuel=\"40\" data-cv=\"50000\" data-eff=\"35\" data-disp=\"12\" data-spd=\"1500\" data-str=\"4\" data-ft=\"natgas\" data-afr=\"17.2\" data-cyl=\"6\">200 kW Gas Engine<\/button>\n        <\/div>\n    <\/form>\n\n    <!-- Results -->\n    <div class=\"vc-results\" id=\"vc-results\">\n        <div class=\"vc-results-head\">\n            <h2 class=\"vc-results-title\">Results<\/h2>\n            <button type=\"button\" class=\"vc-copy-btn\" id=\"vc-copy-btn\">\n                <svg width=\"14\" height=\"14\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><rect x=\"9\" y=\"9\" width=\"13\" height=\"13\" rx=\"2\"\/><path d=\"M5 15H4a2 2 0 01-2-2V4a2 2 0 012-2h9a2 2 0 012 2v1\"\/><\/svg>\n                Copy\n            <\/button>\n        <\/div>\n        <div class=\"vc-result-grid\">\n            <div class=\"vc-rcard vc-rcard-primary\">\n                <div class=\"vc-rcard-label\">Engine Power (COP)<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-power\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Rated Power (with rating factor)<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-rated\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Torque<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-torque\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">BSFC (Brake Specific Fuel Consumption)<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-bsfc\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">BMEP (Brake Mean Effective Pressure)<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-bmep\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Thermal Efficiency<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-eta\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Heat Input (Total Fuel Energy)<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-qin\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Heat Rejected (Cooling + Exhaust)<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-qrej\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Air Mass Flow<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-air\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Power per Cylinder<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-percyl\">\u2014<\/div>\n            <\/div>\n        <\/div>\n    <\/div>\n<\/div>\n\n<!-- Theory & Reference -->\n<div class=\"vc-section vc-open\" id=\"vc-sec-theory\">\n    <button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"true\">\n        <span class=\"vc-section-toggle-text\">\n            <span class=\"vc-section-icon\">\ud83d\udcd8<\/span>\n            <span class=\"vc-section-title\">Theory &amp; Formulas<\/span>\n        <\/span>\n        <svg class=\"vc-section-chevron\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><path d=\"M6 9l6 6 6-6\"\/><\/svg>\n    <\/button>\n    <div class=\"vc-section-body\">\n        <div class=\"vc-section-inner vc-theory\">\n            <h3>Engine Power from Fuel<\/h3>\n            <p>The brake power output is derived from fuel energy input multiplied by thermal efficiency:<\/p>\n            <div class=\"vc-formula-box\" id=\"vc-katex-1\"><\/div>\n            <ul>\n                <li><strong>\u1e41_f<\/strong> \u2014 fuel mass flow rate (kg\/s)<\/li>\n                <li><strong>CV<\/strong> \u2014 calorific value of fuel (kJ\/kg)<\/li>\n                <li><strong>\u03b7<\/strong> \u2014 brake thermal efficiency (decimal)<\/li>\n            <\/ul>\n\n            <h3>BSFC \u2014 Brake Specific Fuel Consumption<\/h3>\n            <div class=\"vc-formula-box\" id=\"vc-katex-2\"><\/div>\n            <p>BSFC indicates how efficiently the engine converts fuel to work. Lower is better. Typical diesel: 190\u2013230 g\/kWh.<\/p>\n\n            <h3>BMEP \u2014 Brake Mean Effective Pressure<\/h3>\n            <div class=\"vc-formula-box\" id=\"vc-katex-3\"><\/div>\n            <ul>\n                <li><strong>n_R<\/strong> \u2014 revolutions per power stroke (2 for 4-stroke, 1 for 2-stroke)<\/li>\n                <li><strong>V_d<\/strong> \u2014 total displacement (m\u00b3)<\/li>\n                <li><strong>n<\/strong> \u2014 engine speed (rev\/s)<\/li>\n            <\/ul>\n\n            <h3>Torque<\/h3>\n            <div class=\"vc-formula-box\" id=\"vc-katex-4\"><\/div>\n\n            <h3>ISO 3046 Power Rating Types<\/h3>\n            <table class=\"vc-table\">\n                <thead><tr><th>Rating<\/th><th>Code<\/th><th>Factor<\/th><th>Description<\/th><\/tr><\/thead>\n                <tbody>\n                    <tr><td>Continuous<\/td><td>COP<\/td><td>1.0\u00d7<\/td><td>Unlimited hours at constant load<\/td><\/tr>\n                    <tr><td>Prime<\/td><td>PRP<\/td><td>1.1\u00d7<\/td><td>Unlimited hours, variable load, avg \u2264 80% of PRP<\/td><\/tr>\n                    <tr><td>Limited Time<\/td><td>LTP<\/td><td>1.2\u00d7<\/td><td>Max 500 h\/year at 100% LTP<\/td><\/tr>\n                    <tr><td>Emergency Standby<\/td><td>ESP<\/td><td>1.3\u00d7<\/td><td>Max 200 h\/year, no overload allowed<\/td><\/tr>\n                <\/tbody>\n            <\/table>\n\n            <h3>Practical Example<\/h3>\n            <div class=\"vc-example-box\">\n                <div class=\"vc-example-title\">Example \u2014 6-Cylinder Turbocharged Diesel, 12 L<\/div>\n                <p><strong>Given:<\/strong> Fuel consumption = 50 kg\/h, CV = 42,700 kJ\/kg, \u03b7 = 38%, Displacement = 12 L, Speed = 1500 RPM, 4-stroke<\/p>\n                <p>Q_in = 50 \u00d7 42,700 \/ 3600 = <strong>593.1 kW (thermal)<\/strong><\/p>\n                <p>P = 593.1 \u00d7 0.38 = <strong>225.4 kW<\/strong><\/p>\n                <p>BSFC = 50,000 \/ 225.4 = <strong>221.8 g\/kWh<\/strong><\/p>\n                <p>Torque = 225,400 \/ (2\u03c0 \u00d7 25) = <strong>1435 N\u00b7m<\/strong><\/p>\n                <p>BMEP = 225,400 \u00d7 2 \u00d7 60 \/ (0.012 \u00d7 1500) = <strong>15.0 bar<\/strong><\/p>\n            <\/div>\n\n            <h3>Diesel vs Gas Engine Comparison<\/h3>\n            <table class=\"vc-table\">\n                <thead><tr><th>Parameter<\/th><th>Diesel<\/th><th>Natural Gas<\/th><\/tr><\/thead>\n                <tbody>\n                    <tr><td>Thermal Efficiency<\/td><td>35\u201352%<\/td><td>28\u201342%<\/td><\/tr>\n                    <tr><td>BSFC (equivalent)<\/td><td>190\u2013230 g\/kWh<\/td><td>230\u2013300 g\/kWh<\/td><\/tr>\n                    <tr><td>BMEP (turbocharged)<\/td><td>15\u201325 bar<\/td><td>12\u201320 bar<\/td><\/tr>\n                    <tr><td>A\/F Ratio (stoich.)<\/td><td>14.5:1<\/td><td>17.2:1<\/td><\/tr>\n                    <tr><td>Compression Ratio<\/td><td>15\u201322:1<\/td><td>10\u201314:1<\/td><\/tr>\n                    <tr><td>CO\u2082 per kWh<\/td><td>~650 g<\/td><td>~490 g<\/td><\/tr>\n                    <tr><td>NOx<\/td><td>Higher<\/td><td>Lower (lean burn)<\/td><\/tr>\n                <\/tbody>\n            <\/table>\n\n            <h3>Typical Engine BSFC Values<\/h3>\n            <table class=\"vc-table\">\n                <thead><tr><th>Engine Type<\/th><th>BSFC (g\/kWh)<\/th><th>Efficiency<\/th><\/tr><\/thead>\n                <tbody>\n                    <tr><td>Small high-speed diesel (&lt;100 kW)<\/td><td>230\u2013270<\/td><td>30\u201336%<\/td><\/tr>\n                    <tr><td>Medium-speed diesel (100\u20131000 kW)<\/td><td>195\u2013230<\/td><td>35\u201342%<\/td><\/tr>\n                    <tr><td>Large medium-speed (1\u201310 MW)<\/td><td>180\u2013200<\/td><td>40\u201346%<\/td><\/tr>\n                    <tr><td>Slow-speed marine diesel (10+ MW)<\/td><td>160\u2013175<\/td><td>48\u201352%<\/td><\/tr>\n                    <tr><td>Gas engine (lean burn)<\/td><td>230\u2013280 (eq.)<\/td><td>35\u201342%<\/td><\/tr>\n                <\/tbody>\n            <\/table>\n\n            <div class=\"vc-warning-box\">\n                <p style=\"margin:0;font-size:14px;color:var(--vc-ink-secondary);\"><strong>\u26a0\ufe0f Note:<\/strong> ISO 3046 reference conditions: 25 \u00b0C, 100 kPa, 30% relative humidity. Derate approximately 3.5% per 300 m above 300 m altitude and ~2% per 5.5 \u00b0C above 25 \u00b0C.<\/p>\n            <\/div>\n        <\/div>\n    <\/div>\n<\/div>\n\n<!-- Related Calculators -->\n<div class=\"vc-section\" id=\"vc-sec-related\">\n    <button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"false\">\n        <span class=\"vc-section-toggle-text\">\n            <span class=\"vc-section-icon\">\ud83d\udd17<\/span>\n            <span class=\"vc-section-title\">Related Calculators<\/span>\n        <\/span>\n        <svg class=\"vc-section-chevron\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><path d=\"M6 9l6 6 6-6\"\/><\/svg>\n    <\/button>\n    <div class=\"vc-section-body\">\n        <div class=\"vc-section-inner\">\n            <div class=\"vc-related\">\n                <a class=\"vc-related-link\" href=\"\/calculators\/hydraulic-cylinder-calculator\/\">Hydraulic Cylinder<\/a>\n                <a class=\"vc-related-link\" href=\"\/calculators\/pipe-pressure-drop\/\">Pipe Pressure Drop<\/a>\n                <a class=\"vc-related-link\" href=\"\/calculators\/gear-oil-quantity\/\">Gear Oil Quantity<\/a>\n                <a class=\"vc-related-link\" href=\"\/calculators\/oil-viscosity-temperature\/\">Oil Viscosity\u2013Temperature<\/a>\n                <a class=\"vc-related-link\" href=\"\/calculators\/thermal-expansion-calculator\/\">Thermal Expansion<\/a>\n            <\/div>\n        <\/div>\n    <\/div>\n<\/div>\n\n<!-- FAQ -->\n<div class=\"vc-section\" id=\"vc-sec-faq\">\n    <button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"false\">\n        <span class=\"vc-section-toggle-text\">\n            <span class=\"vc-section-icon\">\u2753<\/span>\n            <span class=\"vc-section-title\">Frequently Asked Questions<\/span>\n        <\/span>\n        <svg class=\"vc-section-chevron\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><path d=\"M6 9l6 6 6-6\"\/><\/svg>\n    <\/button>\n    <div class=\"vc-section-body\">\n        <div class=\"vc-section-inner\">\n            <div class=\"vc-faq-list\" id=\"vc-faq-list\"><\/div>\n        <\/div>\n    <\/div>\n<\/div>\n\n<!-- Promo -->\n<div class=\"vc-promo\">\n    <div class=\"vc-promo-text\">\n        <strong>Vibromera \u2014 Portable Balancing &amp; Vibration Analysis<\/strong><br>\n        Professional field balancing instruments and software. Used in 50+ countries.\n    <\/div>\n    <a class=\"vc-promo-link\" href=\"https:\/\/vibromera.eu\/\" target=\"_blank\" rel=\"noopener\">Learn More<\/a>\n<\/div>\n\n<!-- Footer -->\n<footer class=\"vc-footer\">\n    <p>\u00a9 2024\u20132025 <a href=\"https:\/\/vibromera.eu\/\">Vibromera<\/a> \u2014 Engineering Calculators<\/p>\n    <p style=\"font-size:12px;margin-top:4px;\">Based on ISO 3046 standards. Last updated: June 2025<\/p>\n    <div class=\"vc-footer-links\">\n        <a href=\"\/calculators\/engineering-calculators\/\">All Calculators<\/a>\n        <a href=\"https:\/\/vibromera.eu\/contacts\/\">Contact<\/a>\n    <\/div>\n<\/footer>\n\n<\/div>\n\n<script src=\"https:\/\/cdn.jsdelivr.net\/npm\/katex@0.16.11\/dist\/katex.min.js\"><\/script>\n<script>\n(function() {\n    'use strict';\n\n    var SLUG = 'engine-parameters-iso3046';\n    var unitSystem = 'metric';\n    var KW2HP = 1.34102;\n    var KGH2LBH = 2.20462;\n    var BAR2PSI = 14.5038;\n    var NM2LBFT = 0.73756;\n\n    var FUEL_CV = { diesel: 42700, hfo: 40200, natgas: 50000, lpg: 46000 };\n\n    function $(id) { return document.getElementById(id); }\n    function fmt(n, d) {\n        if (isNaN(n) || !isFinite(n)) return '\u2014';\n        var f = n.toFixed(d === undefined ? 2 : d);\n        return f.replace(\/(\\.\\d*?)0+$\/, '$1').replace(\/\\.$\/, '');\n    }\n\n    \/* \u2500\u2500 FUEL TYPE CHANGE \u2500\u2500 *\/\n    $('vc-ftype').addEventListener('change', function() {\n        var ft = this.value;\n        if (FUEL_CV[ft]) {\n            $('vc-cv').value = FUEL_CV[ft];\n            if (ft === 'diesel' || ft === 'hfo') $('vc-afr').value = '14.5';\n            else if (ft === 'natgas') $('vc-afr').value = '17.2';\n            else if (ft === 'lpg') $('vc-afr').value = '15.7';\n        }\n        calculate();\n    });\n\n    \/* \u2500\u2500 CALCULATION \u2500\u2500 *\/\n    function calculate() {\n        var mf = parseFloat($('vc-fuel').value);\n        var cv = parseFloat($('vc-cv').value);\n        var eff = parseFloat($('vc-eff').value) \/ 100;\n        var disp = parseFloat($('vc-disp').value);\n        var n = parseFloat($('vc-speed').value);\n        var stroke = parseInt($('vc-stroke').value);\n        var rating = parseFloat($('vc-rating').value);\n        var afr = parseFloat($('vc-afr').value) || 14.5;\n        var ncyl = parseInt($('vc-ncyl').value) || 6;\n\n        if (!mf || !cv || !eff || mf <= 0 || cv <= 0 || eff <= 0) {\n            $('vc-results').classList.remove('vc-visible');\n            return;\n        }\n\n        \/\/ Core calculations (metric)\n        var Qin = mf * cv \/ 3600; \/\/ kW thermal\n        var P = Qin * eff; \/\/ kW brake\n        var Prated = P * rating;\n        var bsfc = (mf * 1000) \/ P; \/\/ g\/kWh (mf in kg\/h \u00d7 1000 = g\/h \/ P)\n        var torque = n > 0 ? P * 1000 \/ (2 * Math.PI * n \/ 60) : 0; \/\/ N\u00b7m\n        var nR = stroke === 4 ? 2 : 1;\n        var bmep = (disp > 0 && n > 0) ? (P * 1000 * nR * 60) \/ ((disp \/ 1000) * n) \/ 1e5 : 0; \/\/ bar\n        var airFlow = mf * afr; \/\/ kg\/h\n        var Qrej = Qin - P;\n        var perCyl = P \/ ncyl;\n\n        \/\/ Display\n        if (unitSystem === 'imperial') {\n            $('vc-r-power').innerHTML = fmt(P * KW2HP, 1) + ' <span class=\"vc-rcard-unit\">HP<\/span> <span class=\"vc-rcard-unit\">(' + fmt(P, 1) + ' kW)<\/span>';\n            $('vc-r-rated').innerHTML = fmt(Prated * KW2HP, 1) + ' <span class=\"vc-rcard-unit\">HP<\/span>';\n            $('vc-r-torque').innerHTML = fmt(torque * NM2LBFT, 1) + ' <span class=\"vc-rcard-unit\">lb\u00b7ft<\/span>';\n            $('vc-r-bmep').innerHTML = fmt(bmep * BAR2PSI, 1) + ' <span class=\"vc-rcard-unit\">psi<\/span>';\n        } else {\n            $('vc-r-power').innerHTML = fmt(P, 1) + ' <span class=\"vc-rcard-unit\">kW<\/span> <span class=\"vc-rcard-unit\">(' + fmt(P * KW2HP, 0) + ' HP)<\/span>';\n            $('vc-r-rated').innerHTML = fmt(Prated, 1) + ' <span class=\"vc-rcard-unit\">kW<\/span>';\n            $('vc-r-torque').innerHTML = fmt(torque, 0) + ' <span class=\"vc-rcard-unit\">N\u00b7m<\/span>';\n            $('vc-r-bmep').innerHTML = fmt(bmep, 2) + ' <span class=\"vc-rcard-unit\">bar<\/span>';\n        }\n\n        $('vc-r-bsfc').innerHTML = fmt(bsfc, 1) + ' <span class=\"vc-rcard-unit\">g\/kWh<\/span>';\n        $('vc-r-eta').innerHTML = fmt(eff * 100, 1) + ' <span class=\"vc-rcard-unit\">%<\/span>';\n        $('vc-r-qin').innerHTML = fmt(Qin, 1) + ' <span class=\"vc-rcard-unit\">kW thermal<\/span>';\n        $('vc-r-qrej').innerHTML = fmt(Qrej, 1) + ' <span class=\"vc-rcard-unit\">kW<\/span> <span class=\"vc-rcard-unit\">(' + fmt(Qrej \/ Qin * 100, 0) + '% of input)<\/span>';\n        $('vc-r-air').innerHTML = fmt(airFlow, 1) + ' <span class=\"vc-rcard-unit\">kg\/h<\/span> <span class=\"vc-rcard-unit\">(A\/F=' + fmt(afr, 1) + ':1)<\/span>';\n        $('vc-r-percyl').innerHTML = fmt(perCyl, 1) + ' <span class=\"vc-rcard-unit\">kW\/cyl<\/span> <span class=\"vc-rcard-unit\">(' + ncyl + ' cylinders)<\/span>';\n\n        $('vc-results').classList.add('vc-visible');\n\n        \/\/ URL params\n        try {\n            var u = new URL(window.location);\n            u.searchParams.set('fuel', mf);\n            u.searchParams.set('cv', cv);\n            u.searchParams.set('eff', $('vc-eff').value);\n            u.searchParams.set('disp', disp);\n            u.searchParams.set('speed', n);\n            u.searchParams.set('stroke', stroke);\n            u.searchParams.set('rating', rating);\n            history.replaceState(null, '', u.toString());\n        } catch (e) {}\n\n        \/\/ History\n        saveHistory({\n            fuel: mf, cv: cv, eff: $('vc-eff').value, power: fmt(P, 1),\n            _summary: fmt(P, 0) + ' kW, BSFC ' + fmt(bsfc, 0) + ' g\/kWh, BMEP ' + fmt(bmep, 1) + ' bar'\n        });\n    }\n\n    \/* \u2500\u2500 UNIT TOGGLE \u2500\u2500 *\/\n    var unitBtns = document.querySelectorAll('.vc-unit-btn');\n    unitBtns.forEach(function(btn) {\n        btn.addEventListener('click', function() {\n            unitBtns.forEach(function(b) { b.classList.remove('vc-active'); });\n            this.classList.add('vc-active');\n            unitSystem = this.getAttribute('data-system');\n            $('vc-fuel-hint').textContent = unitSystem === 'imperial' ? '(lb\/h)' : '(kg\/h)';\n            try { localStorage.setItem('vc_units', unitSystem); } catch (e) {}\n            calculate();\n        });\n    });\n\n    \/* \u2500\u2500 PRESETS \u2500\u2500 *\/\n    document.querySelectorAll('.vc-preset-btn').forEach(function(btn) {\n        btn.addEventListener('click', function(e) {\n            e.preventDefault();\n            $('vc-fuel').value = this.getAttribute('data-fuel');\n            $('vc-cv').value = this.getAttribute('data-cv');\n            $('vc-eff').value = this.getAttribute('data-eff');\n            $('vc-disp').value = this.getAttribute('data-disp');\n            $('vc-speed').value = this.getAttribute('data-spd');\n            $('vc-stroke').value = this.getAttribute('data-str');\n            $('vc-ftype').value = this.getAttribute('data-ft');\n            $('vc-afr').value = this.getAttribute('data-afr');\n            $('vc-ncyl').value = this.getAttribute('data-cyl');\n            calculate();\n        });\n    });\n\n    \/* \u2500\u2500 AUTO-CALCULATE \u2500\u2500 *\/\n    $('vc-form').addEventListener('input', calculate);\n    $('vc-form').addEventListener('change', calculate);\n\n    \/* \u2500\u2500 COPY \u2500\u2500 *\/\n    $('vc-copy-btn').addEventListener('click', function() {\n        var text = 'Engine Parameters (ISO 3046)\\n' +\n            '\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\\n' +\n            'Power: ' + $('vc-r-power').textContent + '\\n' +\n            'Rated: ' + $('vc-r-rated').textContent + '\\n' +\n            'Torque: ' + $('vc-r-torque').textContent + '\\n' +\n            'BSFC: ' + $('vc-r-bsfc').textContent + '\\n' +\n            'BMEP: ' + $('vc-r-bmep').textContent + '\\n' +\n            'Efficiency: ' + $('vc-r-eta').textContent + '\\n' +\n            'Heat Input: ' + $('vc-r-qin').textContent + '\\n' +\n            'Heat Rejected: ' + $('vc-r-qrej').textContent + '\\n' +\n            'Air Flow: ' + $('vc-r-air').textContent + '\\n' +\n            '\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\\n' +\n            'vibromera.eu\/calculators\/engine-parameters-iso3046\/';\n\n        if (navigator.clipboard) {\n            navigator.clipboard.writeText(text).then(function() {\n                var btn = $('vc-copy-btn');\n                btn.classList.add('vc-copied');\n                btn.innerHTML = '<svg width=\"14\" height=\"14\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><polyline points=\"20 6 9 17 4 12\"\/><\/svg> Copied!';\n                setTimeout(function() {\n                    btn.classList.remove('vc-copied');\n                    btn.innerHTML = '<svg width=\"14\" height=\"14\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><rect x=\"9\" y=\"9\" width=\"13\" height=\"13\" rx=\"2\"\/><path d=\"M5 15H4a2 2 0 01-2-2V4a2 2 0 012-2h9a2 2 0 012 2v1\"\/><\/svg> Copy';\n                }, 2000);\n            });\n        }\n    });\n\n    \/* \u2500\u2500 COLLAPSIBLE SECTIONS \u2500\u2500 *\/\n    document.querySelectorAll('.vc-section-toggle').forEach(function(btn) {\n        btn.addEventListener('click', function() {\n            var section = this.closest('.vc-section');\n            var isOpen = section.classList.contains('vc-open');\n            section.classList.toggle('vc-open');\n            this.setAttribute('aria-expanded', !isOpen);\n        });\n    });\n\n    \/* \u2500\u2500 FAQ \u2500\u2500 *\/\n    var faqData = [\n        { q: 'What is BSFC and what are typical values?', a: '<p>Brake Specific Fuel Consumption is the fuel consumed per unit power per hour, in g\/kWh. It directly indicates engine efficiency:<\/p><ul><li><strong>Small high-speed diesel:<\/strong> 230\u2013270 g\/kWh<\/li><li><strong>Medium-speed diesel:<\/strong> 195\u2013230 g\/kWh<\/li><li><strong>Large slow-speed marine:<\/strong> 160\u2013175 g\/kWh<\/li><li><strong>Gas engine (lean burn):<\/strong> 230\u2013280 g\/kWh equivalent<\/li><\/ul><p>Lower BSFC = higher efficiency = less fuel per kW.<\/p>' },\n        { q: 'What is BMEP and why does it matter?', a: '<p>BMEP (Brake Mean Effective Pressure) is the hypothetical constant pressure acting on the piston that would produce the same net work per cycle. It normalizes performance independent of engine size.<\/p><ul><li><strong>Naturally aspirated diesel:<\/strong> 7\u201310 bar<\/li><li><strong>Turbocharged diesel:<\/strong> 15\u201325 bar<\/li><li><strong>High-performance racing:<\/strong> 25\u201330+ bar<\/li><\/ul><p>Higher BMEP means more power from a given displacement \u2014 a measure of specific output.<\/p>' },\n        { q: 'What are the ISO 3046 power rating categories?', a: '<p>ISO 3046-1 defines four standard power ratings for reciprocating IC engines:<\/p><ul><li><strong>COP:<\/strong> Continuous Power \u2014 unlimited running at constant load<\/li><li><strong>PRP:<\/strong> Prime Power \u2014 unlimited hours at variable load (avg \u2264 80%)<\/li><li><strong>LTP:<\/strong> Limited Time Power \u2014 max 500 h\/year at 100%<\/li><li><strong>ESP:<\/strong> Emergency Standby \u2014 max 200 h\/year<\/li><\/ul><p>Reference conditions: 25\u00b0C, 100 kPa, 30% relative humidity.<\/p>' },\n        { q: 'How do I derate an engine for altitude and temperature?', a: '<p>Per ISO 3046-1, engine power must be derated when operating above reference conditions:<\/p><ul><li><strong>Altitude:<\/strong> ~3.5% per 300 m above 300 m elevation<\/li><li><strong>Temperature:<\/strong> ~2% per 5.5\u00b0C above 25\u00b0C ambient<\/li><li><strong>Humidity:<\/strong> minor effect, usually neglected<\/li><\/ul><p>Example: at 1500 m altitude and 40\u00b0C, derating \u2248 3.5%\u00d74 + 2%\u00d72.7 \u2248 19.4%.<\/p>' },\n        { q: 'What is the difference between diesel and gas engine efficiency?', a: '<p>Diesel engines are inherently more efficient (35\u201352%) due to higher compression ratios (15\u201322:1) and lean combustion. Gas engines (28\u201342%) use lower compression (10\u201314:1) but produce less NOx.<\/p><p>For the same power output, gas engines consume more fuel (by energy) but produce ~25% less CO\u2082 per kWh due to the hydrogen content of methane.<\/p>' }\n    ];\n\n    var faqList = $('vc-faq-list');\n    faqData.forEach(function(faq) {\n        faqList.innerHTML += '<div class=\"vc-faq-item\"><button type=\"button\" class=\"vc-faq-q\"><span>' + faq.q + '<\/span><svg class=\"vc-faq-chevron\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><path d=\"M6 9l6 6 6-6\"\/><\/svg><\/button><div class=\"vc-faq-a\"><div class=\"vc-faq-a-inner\">' + faq.a + '<\/div><\/div><\/div>';\n    });\n    faqList.addEventListener('click', function(e) {\n        var btn = e.target.closest('.vc-faq-q');\n        if (!btn) return;\n        btn.closest('.vc-faq-item').classList.toggle('vc-open');\n    });\n\n    \/* \u2500\u2500 HISTORY \u2500\u2500 *\/\n    function saveHistory(entry) {\n        var key = 'vc_history_' + SLUG;\n        var arr = [];\n        try { arr = JSON.parse(localStorage.getItem(key)) || []; } catch (e) {}\n        entry._ts = new Date().toISOString();\n        arr.unshift(entry);\n        if (arr.length > 10) arr = arr.slice(0, 10);\n        try { localStorage.setItem(key, JSON.stringify(arr)); } catch (e) {}\n    }\n\n    \/* \u2500\u2500 URL PARAMS \u2500\u2500 *\/\n    function loadParams() {\n        try {\n            var p = new URLSearchParams(window.location.search);\n            if (p.has('fuel')) $('vc-fuel').value = p.get('fuel');\n            if (p.has('cv')) $('vc-cv').value = p.get('cv');\n            if (p.has('eff')) $('vc-eff').value = p.get('eff');\n            if (p.has('disp')) $('vc-disp').value = p.get('disp');\n            if (p.has('speed')) $('vc-speed').value = p.get('speed');\n            if (p.has('stroke')) $('vc-stroke').value = p.get('stroke');\n            if (p.has('rating')) $('vc-rating').value = p.get('rating');\n        } catch (e) {}\n    }\n\n    \/* \u2500\u2500 KATEX \u2500\u2500 *\/\n    function renderFormulas() {\n        try {\n            katex.render('P = \\\\dot{m}_f \\\\times CV \\\\times \\\\eta \\\\quad [\\\\text{kW}]', $('vc-katex-1'), { displayMode: true, throwOnError: false });\n            katex.render('BSFC = \\\\frac{\\\\dot{m}_f}{P} \\\\times 1000 \\\\quad [\\\\text{g\/kWh}]', $('vc-katex-2'), { displayMode: true, throwOnError: false });\n            katex.render('BMEP = \\\\frac{P \\\\cdot n_R \\\\cdot 60}{V_d \\\\cdot n} \\\\quad [\\\\text{Pa}]', $('vc-katex-3'), { displayMode: true, throwOnError: false });\n            katex.render('T = \\\\frac{P}{2\\\\pi \\\\cdot n\/60} = \\\\frac{P \\\\times 9549}{n} \\\\quad [\\\\text{N\u00b7m}]', $('vc-katex-4'), { displayMode: true, throwOnError: false });\n        } catch (e) {}\n    }\n\n    \/* \u2500\u2500 INIT \u2500\u2500 *\/\n    function init() {\n        try {\n            var saved = localStorage.getItem('vc_units');\n            if (saved === 'imperial') {\n                unitSystem = 'imperial';\n                unitBtns.forEach(function(b) { b.classList.toggle('vc-active', b.getAttribute('data-system') === 'imperial'); });\n                $('vc-fuel-hint').textContent = '(lb\/h)';\n            }\n        } catch (e) {}\n\n        loadParams();\n        renderFormulas();\n        calculate();\n    }\n\n    if (document.readyState === 'loading') {\n        document.addEventListener('DOMContentLoaded', init);\n    } else {\n        init();\n    }\n})();\n<\/script>\n","protected":false},"excerpt":{"rendered":"<p>ISO 3046 \u0985\u09a8\u09c1\u09b8\u09be\u09b0\u09c7 \u09ac\u09bf\u09a8\u09be\u09ae\u09c2\u09b2\u09cd\u09af\u09c7 \u0987\u099e\u09cd\u099c\u09bf\u09a8 \u09aa\u09b0\u09be\u09ae\u09bf\u09a4\u09bf \u0995\u09cd\u09af\u09be\u09b2\u0995\u09c1\u09b2\u09c7\u099f\u09b0\u0964 \u099c\u09cd\u09ac\u09be\u09b2\u09be\u09a8\u09c0 \u0996\u09b0\u099a \u09a5\u09c7\u0995\u09c7 \u09b6\u0995\u09cd\u09a4\u09bf, BSFC, BMEP, \u099f\u09b0\u09cd\u0995, \u09a4\u09be\u09aa\u09c0\u09af\u09bc \u09a6\u0995\u09cd\u09b7\u09a4\u09be, \u09ac\u09be\u09af\u09bc\u09c1\/\u099c\u09cd\u09ac\u09be\u09b2\u09be\u09a8\u09c0 \u0985\u09a8\u09c1\u09aa\u09be\u09a4 \u0997\u09a3\u09a8\u09be \u0995\u09b0\u09c1\u09a8\u0964 \u09a1\u09bf\u099c\u09c7\u09b2 \u09ac\u09a8\u09be\u09ae \u0997\u09cd\u09af\u09be\u09b8 \u0987\u099e\u09cd\u099c\u09bf\u09a8 \u09a4\u09c1\u09b2\u09a8\u09be\u0964<\/p>","protected":false},"featured_media":0,"template":"","meta":{"ai_generated_summary":"","footnotes":""},"categories":[],"tags":[],"class_list":["post-100081","calculator","type-calculator","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/calculator\/100081","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/calculator"}],"about":[{"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/types\/calculator"}],"version-history":[{"count":1,"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/calculator\/100081\/revisions"}],"predecessor-version":[{"id":100396,"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/calculator\/100081\/revisions\/100396"}],"wp:attachment":[{"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/media?parent=100081"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/categories?post=100081"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/tags?post=100081"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}