{"id":255,"date":"2025-10-31T00:25:51","date_gmt":"2025-10-31T00:25:51","guid":{"rendered":"https:\/\/vibromera.eu\/glossary\/steam-whirl\/"},"modified":"2026-05-23T22:54:27","modified_gmt":"2026-05-23T22:54:27","slug":"steam-whirl","status":"publish","type":"glossary","link":"https:\/\/vibromera.eu\/hy\/glossary\/steam-whirl\/","title":{"rendered":"What is Steam Whirl? Aerodynamic Instability in Turbines"},"content":{"rendered":"<h1>Understanding Steam Whirl in Turbomachinery<\/h1>\n\t\t<section class=\"woocommerce hestia-shop products is-shortcode\" id=\"products\" data-sorder=\"hestia_shop\" >\n\t\t\t\t\t\t<div class=\"\">\n\t\t\t\t\t\t<div class=\"hestia-shop-content\">\n\t\t\t<div class=\"row\" data-aos=\"fade-up\" >\t\t\t\t\t<div class=\"col-ms-6 col-sm-6 col-md-3 shop-item\">\n\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/hy\/product\/balanset-1\/\" class=\"woocommerce-LoopProduct-link woocommerce-loop-product__link\">\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"card-image\">\n\t\t\t\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/hy\/product\/balanset-1\/\" title=\"Portable balancer &#038; Vibration analyzer Balanset-1A\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"230\" height=\"153\" src=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2023\/09\/77-e1693745667801-230x153.webp\" class=\"attachment-woocommerce_thumbnail size-woocommerce_thumbnail\" alt=\"Balanset-1A full kit portable balancer and vibration analyzer\" srcset=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2023\/09\/77-e1693745667801-230x153.webp 230w, https:\/\/vibromera.eu\/wp-content\/uploads\/2023\/09\/77-e1693745667801-18x12.webp 18w, https:\/\/vibromera.eu\/wp-content\/uploads\/2023\/09\/77-e1693745667801-360x240.webp 360w, https:\/\/vibromera.eu\/wp-content\/uploads\/2023\/09\/77-e1693745667801-272x182.webp 272w\" sizes=\"auto, (max-width: 230px) 100vw, 230px\" \/>\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t\t\t\t\t\t\t<div class=\"ripple-container\"><\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"content\">\n\t\t\t\t\t\t\t\t<span class=\"category\"><a href=\"https:\/\/vibromera.eu\/hy\/product-category\/devices\/\" rel=\"tag\">Devices<\/a><\/span>\n\t\t\t\t\t\t\t\t<h4 class=\"card-title\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"shop-item-title-link\" href=\"https:\/\/vibromera.eu\/hy\/product\/balanset-1\/\" title=\"Portable balancer &#038; Vibration analyzer Balanset-1A\">Portable balancer &#038; Vibration analyzer Balanset-1A<\/a>\n\n\t\t\t\t\t\t\t\t<\/h4>\n\n\t\t\t\t\t\t\t\t\n\t\t\t\t\t\t\t\t<div class=\"footer\">\n\n\t\t\t\t\t\t\t\t\t<div class=\"price\"><h4><span class=\"woocommerce-Price-amount amount\"><span class=\"woocommerce-Price-currencySymbol\">&euro;<\/span>1,975.00<\/span> + VAT (if applicable)<\/h4><\/div>\n\t\t\t\t\t\t\t\t\t<div class=\"stats\">\n\t\t\t\t\t\t\t\t\t\t<a rel=\"nofollow\" href=\"\/hy\/wp-json\/wp\/v2\/glossary\/255?add-to-cart=986\" data-quantity=\"1\" data-product_id=\"986\" data-product_sku=\"BS-1\" class=\"button product_type_simple add_to_cart_button ajax_add_to_cart btn btn-just-icon btn-simple btn-default\" title=\"Add to cart\" data-no-translation-title=\"\"><i rel=\"tooltip\" data-original-title=\"Add to cart\" class=\"fas fa-cart-plus\" data-no-translation-data-original-title=\"\"><\/i><\/a>\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/a><a href=\"\/hy\/wp-json\/wp\/v2\/glossary\/255?add-to-cart=986\" aria-describedby=\"woocommerce_loop_add_to_cart_link_describedby_986\" data-quantity=\"1\" class=\"button product_type_simple add_to_cart_button ajax_add_to_cart\" data-product_id=\"986\" data-product_sku=\"BS-1\" aria-label=\"Add to cart: \u201cPortable balancer &amp; Vibration analyzer Balanset-1A\u201d\" rel=\"nofollow\" data-success_message=\"\u201cPortable balancer &amp; Vibration analyzer Balanset-1A\u201d has been added to your cart\" data-no-translation=\"\" data-trp-gettext=\"\" data-no-translation-aria-label=\"\" data-no-translation-data-success_message=\"\">Add to cart<\/a>\t<span id=\"woocommerce_loop_add_to_cart_link_describedby_986\" class=\"screen-reader-text\">\n\t\t\t<\/span>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t<div class=\"col-ms-6 col-sm-6 col-md-3 shop-item\">\n\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/hy\/product\/vibration-sensor\/\" class=\"woocommerce-LoopProduct-link woocommerce-loop-product__link\">\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"card-image\">\n\t\t\t\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/hy\/product\/vibration-sensor\/\" title=\"Vibration sensor\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"230\" height=\"153\" src=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-3-230x153.webp\" class=\"attachment-woocommerce_thumbnail size-woocommerce_thumbnail\" alt=\"Balanset-1A vibration sensor close-up\" srcset=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-3-230x153.webp 230w, https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-3-600x400.webp 600w, https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-3-300x200.webp 300w, https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-3-768x512.webp 768w, https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-3-1024x682.webp 1024w, https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-3-272x182.webp 272w, https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-3.webp 1280w\" sizes=\"auto, (max-width: 230px) 100vw, 230px\" \/>\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t\t\t\t\t\t\t<div class=\"ripple-container\"><\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"content\">\n\t\t\t\t\t\t\t\t<span class=\"category\"><a href=\"https:\/\/vibromera.eu\/hy\/product-category\/parts\/\" rel=\"tag\">Parts<\/a><\/span>\n\t\t\t\t\t\t\t\t<h4 class=\"card-title\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"shop-item-title-link\" href=\"https:\/\/vibromera.eu\/hy\/product\/vibration-sensor\/\" title=\"Vibration sensor\">Vibration sensor<\/a>\n\n\t\t\t\t\t\t\t\t<\/h4>\n\n\t\t\t\t\t\t\t\t\n\t\t\t\t\t\t\t\t<div class=\"footer\">\n\n\t\t\t\t\t\t\t\t\t<div class=\"price\"><h4><span class=\"woocommerce-Price-amount amount\"><span class=\"woocommerce-Price-currencySymbol\">&euro;<\/span>90.00<\/span> + VAT (if applicable)<\/h4><\/div>\n\t\t\t\t\t\t\t\t\t<div class=\"stats\">\n\t\t\t\t\t\t\t\t\t\t<a rel=\"nofollow\" href=\"\/hy\/wp-json\/wp\/v2\/glossary\/255?add-to-cart=1820\" data-quantity=\"1\" data-product_id=\"1820\" data-product_sku=\"VS-1\" class=\"button product_type_simple add_to_cart_button ajax_add_to_cart btn btn-just-icon btn-simple btn-default\" title=\"Add to cart\" data-no-translation-title=\"\"><i rel=\"tooltip\" data-original-title=\"Add to cart\" class=\"fas fa-cart-plus\" data-no-translation-data-original-title=\"\"><\/i><\/a>\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/a><a href=\"\/hy\/wp-json\/wp\/v2\/glossary\/255?add-to-cart=1820\" aria-describedby=\"woocommerce_loop_add_to_cart_link_describedby_1820\" data-quantity=\"1\" class=\"button product_type_simple add_to_cart_button ajax_add_to_cart\" data-product_id=\"1820\" data-product_sku=\"VS-1\" aria-label=\"Add to cart: \u201cVibration sensor\u201d\" rel=\"nofollow\" data-success_message=\"\u201cVibration sensor\u201d has been added to your cart\" data-no-translation=\"\" data-trp-gettext=\"\" data-no-translation-aria-label=\"\" data-no-translation-data-success_message=\"\">Add to cart<\/a>\t<span id=\"woocommerce_loop_add_to_cart_link_describedby_1820\" class=\"screen-reader-text\">\n\t\t\t<\/span>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t<div class=\"col-ms-6 col-sm-6 col-md-3 shop-item\">\n\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/hy\/product\/optical-sensor-for-balanset-and-arbalance\/\" class=\"woocommerce-LoopProduct-link woocommerce-loop-product__link\">\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"card-image\">\n\t\t\t\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/hy\/product\/optical-sensor-for-balanset-and-arbalance\/\" title=\"Optical Sensor (Laser Tachometer)\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"230\" height=\"153\" src=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/ZKqzGXSCCBU-230x153.webp\" class=\"attachment-woocommerce_thumbnail size-woocommerce_thumbnail\" alt=\"Optical Sensor (Laser Tachometer)\" srcset=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/ZKqzGXSCCBU-230x153.webp 230w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/ZKqzGXSCCBU-300x200.webp 300w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/ZKqzGXSCCBU-1024x682.webp 1024w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/ZKqzGXSCCBU-768x512.webp 768w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/ZKqzGXSCCBU-1536x1023.webp 1536w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/ZKqzGXSCCBU-18x12.webp 18w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/ZKqzGXSCCBU-360x240.webp 360w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/ZKqzGXSCCBU-460x306.webp 460w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/ZKqzGXSCCBU-600x400.webp 600w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/ZKqzGXSCCBU-272x182.webp 272w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/ZKqzGXSCCBU.webp 1600w\" sizes=\"auto, (max-width: 230px) 100vw, 230px\" \/>\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t\t\t\t\t\t\t<div class=\"ripple-container\"><\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"content\">\n\t\t\t\t\t\t\t\t<span class=\"category\"><a href=\"https:\/\/vibromera.eu\/hy\/product-category\/parts\/\" rel=\"tag\">Parts<\/a><\/span>\n\t\t\t\t\t\t\t\t<h4 class=\"card-title\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"shop-item-title-link\" href=\"https:\/\/vibromera.eu\/hy\/product\/optical-sensor-for-balanset-and-arbalance\/\" title=\"Optical Sensor (Laser Tachometer)\">Optical Sensor (Laser Tachometer)<\/a>\n\n\t\t\t\t\t\t\t\t<\/h4>\n\n\t\t\t\t\t\t\t\t\n\t\t\t\t\t\t\t\t<div class=\"footer\">\n\n\t\t\t\t\t\t\t\t\t<div class=\"price\"><h4><span class=\"woocommerce-Price-amount amount\"><span class=\"woocommerce-Price-currencySymbol\">&euro;<\/span>124.00<\/span> + VAT (if applicable)<\/h4><\/div>\n\t\t\t\t\t\t\t\t\t<div class=\"stats\">\n\t\t\t\t\t\t\t\t\t\t<a rel=\"nofollow\" href=\"\/hy\/wp-json\/wp\/v2\/glossary\/255?add-to-cart=1832\" data-quantity=\"1\" data-product_id=\"1832\" data-product_sku=\"Tach-1\" class=\"button product_type_simple add_to_cart_button ajax_add_to_cart btn btn-just-icon btn-simple btn-default\" title=\"Add to cart\" data-no-translation-title=\"\"><i rel=\"tooltip\" data-original-title=\"Add to cart\" class=\"fas fa-cart-plus\" data-no-translation-data-original-title=\"\"><\/i><\/a>\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/a><a href=\"\/hy\/wp-json\/wp\/v2\/glossary\/255?add-to-cart=1832\" aria-describedby=\"woocommerce_loop_add_to_cart_link_describedby_1832\" data-quantity=\"1\" class=\"button product_type_simple add_to_cart_button ajax_add_to_cart\" data-product_id=\"1832\" data-product_sku=\"Tach-1\" aria-label=\"Add to cart: \u201cOptical Sensor (Laser Tachometer)\u201d\" rel=\"nofollow\" data-success_message=\"\u201cOptical Sensor (Laser Tachometer)\u201d has been added to your cart\" data-no-translation=\"\" data-trp-gettext=\"\" data-no-translation-aria-label=\"\" data-no-translation-data-success_message=\"\">Add to cart<\/a>\t<span id=\"woocommerce_loop_add_to_cart_link_describedby_1832\" class=\"screen-reader-text\">\n\t\t\t<\/span>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t<div class=\"col-ms-6 col-sm-6 col-md-3 shop-item\">\n\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/hy\/product\/balanset-4\/\" class=\"woocommerce-LoopProduct-link woocommerce-loop-product__link\">\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"card-image\">\n\t\t\t\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/hy\/product\/balanset-4\/\" title=\"Balanset-4\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"230\" height=\"153\" src=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/balkom4-230x153.webp\" class=\"attachment-woocommerce_thumbnail size-woocommerce_thumbnail\" alt=\"Vibromera rotor balancing kit: carry case, multi-channel signal conditioner, handheld analyzer, magnetic base, vibration sensors, and coiled cables.\" srcset=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/balkom4-230x153.webp 230w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/balkom4-300x200.webp 300w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/balkom4-18x12.webp 18w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/balkom4-360x240.webp 360w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/balkom4-460x306.webp 460w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/balkom4-600x400.webp 600w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/balkom4-272x182.webp 272w, https:\/\/vibromera.eu\/wp-content\/uploads\/2022\/12\/balkom4.webp 640w\" sizes=\"auto, (max-width: 230px) 100vw, 230px\" \/>\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t\t\t\t\t\t\t<div class=\"ripple-container\"><\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"content\">\n\t\t\t\t\t\t\t\t<span class=\"category\"><a href=\"https:\/\/vibromera.eu\/hy\/product-category\/devices\/\" rel=\"tag\">Devices<\/a><\/span>\n\t\t\t\t\t\t\t\t<h4 class=\"card-title\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"shop-item-title-link\" href=\"https:\/\/vibromera.eu\/hy\/product\/balanset-4\/\" title=\"Balanset-4\">Balanset-4<\/a>\n\n\t\t\t\t\t\t\t\t<\/h4>\n\n\t\t\t\t\t\t\t\t\n\t\t\t\t\t\t\t\t<div class=\"footer\">\n\n\t\t\t\t\t\t\t\t\t<div class=\"price\"><h4><span class=\"woocommerce-Price-amount amount\"><span class=\"woocommerce-Price-currencySymbol\">&euro;<\/span>6,803.00<\/span> + VAT (if applicable)<\/h4><\/div>\n\t\t\t\t\t\t\t\t\t<div class=\"stats\">\n\t\t\t\t\t\t\t\t\t\t<a rel=\"nofollow\" href=\"\/hy\/wp-json\/wp\/v2\/glossary\/255?add-to-cart=1833\" data-quantity=\"1\" data-product_id=\"1833\" data-product_sku=\"BS-4\" class=\"button product_type_simple add_to_cart_button ajax_add_to_cart btn btn-just-icon btn-simple btn-default\" title=\"Add to cart\" data-no-translation-title=\"\"><i rel=\"tooltip\" data-original-title=\"Add to cart\" class=\"fas fa-cart-plus\" data-no-translation-data-original-title=\"\"><\/i><\/a>\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/a><a href=\"\/hy\/wp-json\/wp\/v2\/glossary\/255?add-to-cart=1833\" aria-describedby=\"woocommerce_loop_add_to_cart_link_describedby_1833\" data-quantity=\"1\" class=\"button product_type_simple add_to_cart_button ajax_add_to_cart\" data-product_id=\"1833\" data-product_sku=\"BS-4\" aria-label=\"Add to cart: \u201cBalanset-4\u201d\" rel=\"nofollow\" data-success_message=\"\u201cBalanset-4\u201d has been added to your cart\" data-no-translation=\"\" data-trp-gettext=\"\" data-no-translation-aria-label=\"\" data-no-translation-data-success_message=\"\">Add to cart<\/a>\t<span id=\"woocommerce_loop_add_to_cart_link_describedby_1833\" class=\"screen-reader-text\">\n\t\t\t<\/span>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div><!-- \/.row --><div class=\"row\">\t\t\t\t\t<div class=\"col-ms-6 col-sm-6 col-md-3 shop-item\">\n\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/hy\/product\/magnet-stand\/\" class=\"woocommerce-LoopProduct-link woocommerce-loop-product__link\">\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"card-image\">\n\t\t\t\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/hy\/product\/magnet-stand\/\" title=\"Magnetic Stand Insize-60-kgf\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"230\" height=\"153\" src=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-36-230x153.webp\" class=\"attachment-woocommerce_thumbnail size-woocommerce_thumbnail\" alt=\"Magnet base.\" srcset=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-36-230x153.webp 230w, https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-36-600x400.webp 600w, https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-36-300x200.webp 300w, https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-36-1024x682.webp 1024w, https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-36-768x512.webp 768w, https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-36-360x240.webp 360w, https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-36-272x182.webp 272w, https:\/\/vibromera.eu\/wp-content\/uploads\/2018\/05\/IMG-36.webp 1280w\" sizes=\"auto, (max-width: 230px) 100vw, 230px\" \/>\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t\t\t\t\t\t\t<div class=\"ripple-container\"><\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"content\">\n\t\t\t\t\t\t\t\t<span class=\"category\"><a href=\"https:\/\/vibromera.eu\/hy\/product-category\/parts\/\" rel=\"tag\">Parts<\/a><\/span>\n\t\t\t\t\t\t\t\t<h4 class=\"card-title\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"shop-item-title-link\" href=\"https:\/\/vibromera.eu\/hy\/product\/magnet-stand\/\" title=\"Magnetic Stand Insize-60-kgf\">Magnetic Stand Insize-60-kgf<\/a>\n\n\t\t\t\t\t\t\t\t<\/h4>\n\n\t\t\t\t\t\t\t\t\n\t\t\t\t\t\t\t\t<div class=\"footer\">\n\n\t\t\t\t\t\t\t\t\t<div class=\"price\"><h4><span class=\"woocommerce-Price-amount amount\"><span class=\"woocommerce-Price-currencySymbol\">&euro;<\/span>46.00<\/span> + VAT (if applicable)<\/h4><\/div>\n\t\t\t\t\t\t\t\t\t<div class=\"stats\">\n\t\t\t\t\t\t\t\t\t\t<a rel=\"nofollow\" href=\"\/hy\/wp-json\/wp\/v2\/glossary\/255?add-to-cart=1852\" data-quantity=\"1\" data-product_id=\"1852\" data-product_sku=\"MS-1\" class=\"button product_type_simple add_to_cart_button ajax_add_to_cart btn btn-just-icon btn-simple btn-default\" title=\"Add to cart\" data-no-translation-title=\"\"><i rel=\"tooltip\" data-original-title=\"Add to cart\" class=\"fas fa-cart-plus\" data-no-translation-data-original-title=\"\"><\/i><\/a>\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/a><a href=\"\/hy\/wp-json\/wp\/v2\/glossary\/255?add-to-cart=1852\" aria-describedby=\"woocommerce_loop_add_to_cart_link_describedby_1852\" data-quantity=\"1\" class=\"button product_type_simple add_to_cart_button ajax_add_to_cart\" data-product_id=\"1852\" data-product_sku=\"MS-1\" aria-label=\"Add to cart: \u201cMagnetic Stand Insize-60-kgf\u201d\" rel=\"nofollow\" data-success_message=\"\u201cMagnetic Stand Insize-60-kgf\u201d has been added to your cart\" data-no-translation=\"\" data-trp-gettext=\"\" data-no-translation-aria-label=\"\" data-no-translation-data-success_message=\"\">Add to cart<\/a>\t<span id=\"woocommerce_loop_add_to_cart_link_describedby_1852\" class=\"screen-reader-text\">\n\t\t\t<\/span>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t<div class=\"col-ms-6 col-sm-6 col-md-3 shop-item\">\n\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/hy\/product\/reflective-tape\/\" class=\"woocommerce-LoopProduct-link woocommerce-loop-product__link\">\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"card-image\">\n\t\t\t\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/hy\/product\/reflective-tape\/\" title=\"Reflective tape\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"230\" height=\"153\" src=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2023\/05\/s-l1600-230x153.webp\" class=\"attachment-woocommerce_thumbnail size-woocommerce_thumbnail\" alt=\"Reflective tape\" srcset=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2023\/05\/s-l1600-230x153.webp 230w, https:\/\/vibromera.eu\/wp-content\/uploads\/2023\/05\/s-l1600-16x12.webp 16w, https:\/\/vibromera.eu\/wp-content\/uploads\/2023\/05\/s-l1600-360x240.webp 360w, https:\/\/vibromera.eu\/wp-content\/uploads\/2023\/05\/s-l1600-460x306.webp 460w, https:\/\/vibromera.eu\/wp-content\/uploads\/2023\/05\/s-l1600-272x182.webp 272w\" sizes=\"auto, (max-width: 230px) 100vw, 230px\" \/>\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t\t\t\t\t\t\t<div class=\"ripple-container\"><\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"content\">\n\t\t\t\t\t\t\t\t<span class=\"category\"><a href=\"https:\/\/vibromera.eu\/hy\/product-category\/parts\/\" rel=\"tag\">Parts<\/a><\/span>\n\t\t\t\t\t\t\t\t<h4 class=\"card-title\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"shop-item-title-link\" href=\"https:\/\/vibromera.eu\/hy\/product\/reflective-tape\/\" title=\"Reflective tape\">Reflective tape<\/a>\n\n\t\t\t\t\t\t\t\t<\/h4>\n\n\t\t\t\t\t\t\t\t\n\t\t\t\t\t\t\t\t<div class=\"footer\">\n\n\t\t\t\t\t\t\t\t\t<div class=\"price\"><h4><span class=\"woocommerce-Price-amount amount\"><span class=\"woocommerce-Price-currencySymbol\">&euro;<\/span>10.00<\/span> + VAT (if applicable)<\/h4><\/div>\n\t\t\t\t\t\t\t\t\t<div class=\"stats\">\n\t\t\t\t\t\t\t\t\t\t<a rel=\"nofollow\" href=\"\/hy\/wp-json\/wp\/v2\/glossary\/255?add-to-cart=2329\" data-quantity=\"1\" data-product_id=\"2329\" data-product_sku=\"rt-1\" class=\"button product_type_simple add_to_cart_button ajax_add_to_cart btn btn-just-icon btn-simple btn-default\" title=\"Add to cart\" data-no-translation-title=\"\"><i rel=\"tooltip\" data-original-title=\"Add to cart\" class=\"fas fa-cart-plus\" data-no-translation-data-original-title=\"\"><\/i><\/a>\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/a><a href=\"\/hy\/wp-json\/wp\/v2\/glossary\/255?add-to-cart=2329\" aria-describedby=\"woocommerce_loop_add_to_cart_link_describedby_2329\" data-quantity=\"1\" class=\"button product_type_simple add_to_cart_button ajax_add_to_cart\" data-product_id=\"2329\" data-product_sku=\"rt-1\" aria-label=\"Add to cart: \u201cReflective tape\u201d\" rel=\"nofollow\" data-success_message=\"\u201cReflective tape\u201d has been added to your cart\" data-no-translation=\"\" data-trp-gettext=\"\" data-no-translation-aria-label=\"\" data-no-translation-data-success_message=\"\">Add to cart<\/a>\t<span id=\"woocommerce_loop_add_to_cart_link_describedby_2329\" class=\"screen-reader-text\">\n\t\t\t<\/span>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t<div class=\"col-ms-6 col-sm-6 col-md-3 shop-item\">\n\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/hy\/product\/dynamic-balancer-balanset-1a\/\" class=\"woocommerce-LoopProduct-link woocommerce-loop-product__link\">\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"card-image\">\n\t\t\t\t\t\t\t\t\t<a href=\"https:\/\/vibromera.eu\/hy\/product\/dynamic-balancer-balanset-1a\/\" title=\"Dynamic balancer \u201cBalanset-1A\u201d OEM\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"230\" height=\"153\" src=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2021\/11\/\u0411\u0430\u043b\u043a\u043e\u043c\u041a\u0438\u0442-scaled-230x153.webp\" class=\"attachment-woocommerce_thumbnail size-woocommerce_thumbnail\" alt=\"Balanset-1A kit contents with interface unit, sensors, tachometer and accessories\" srcset=\"https:\/\/vibromera.eu\/wp-content\/uploads\/2021\/11\/\u0411\u0430\u043b\u043a\u043e\u043c\u041a\u0438\u0442-scaled-230x153.webp 230w, https:\/\/vibromera.eu\/wp-content\/uploads\/2021\/11\/\u0411\u0430\u043b\u043a\u043e\u043c\u041a\u0438\u0442-scaled-600x400.webp 600w, https:\/\/vibromera.eu\/wp-content\/uploads\/2021\/11\/\u0411\u0430\u043b\u043a\u043e\u043c\u041a\u0438\u0442-scaled-300x200.webp 300w, https:\/\/vibromera.eu\/wp-content\/uploads\/2021\/11\/\u0411\u0430\u043b\u043a\u043e\u043c\u041a\u0438\u0442-scaled-1024x683.webp 1024w, https:\/\/vibromera.eu\/wp-content\/uploads\/2021\/11\/\u0411\u0430\u043b\u043a\u043e\u043c\u041a\u0438\u0442-scaled-768x512.webp 768w, https:\/\/vibromera.eu\/wp-content\/uploads\/2021\/11\/\u0411\u0430\u043b\u043a\u043e\u043c\u041a\u0438\u0442-scaled-1536x1024.webp 1536w, https:\/\/vibromera.eu\/wp-content\/uploads\/2021\/11\/\u0411\u0430\u043b\u043a\u043e\u043c\u041a\u0438\u0442-scaled-2048x1366.webp 2048w, https:\/\/vibromera.eu\/wp-content\/uploads\/2021\/11\/\u0411\u0430\u043b\u043a\u043e\u043c\u041a\u0438\u0442-scaled-360x240.webp 360w, https:\/\/vibromera.eu\/wp-content\/uploads\/2021\/11\/\u0411\u0430\u043b\u043a\u043e\u043c\u041a\u0438\u0442-scaled-272x182.webp 272w, https:\/\/vibromera.eu\/wp-content\/uploads\/2021\/11\/\u0411\u0430\u043b\u043a\u043e\u043c\u041a\u0438\u0442-scaled-e1732998877834.webp 708w\" sizes=\"auto, (max-width: 230px) 100vw, 230px\" \/>\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t\t\t\t\t\t\t<div class=\"ripple-container\"><\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<div class=\"content\">\n\t\t\t\t\t\t\t\t<span class=\"category\"><a href=\"https:\/\/vibromera.eu\/hy\/product-category\/devices\/\" rel=\"tag\">Devices<\/a><\/span>\n\t\t\t\t\t\t\t\t<h4 class=\"card-title\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"shop-item-title-link\" href=\"https:\/\/vibromera.eu\/hy\/product\/dynamic-balancer-balanset-1a\/\" title=\"Dynamic balancer \u201cBalanset-1A\u201d OEM\">Dynamic balancer \u201cBalanset-1A\u201d OEM<\/a>\n\n\t\t\t\t\t\t\t\t<\/h4>\n\n\t\t\t\t\t\t\t\t\n\t\t\t\t\t\t\t\t<div class=\"footer\">\n\n\t\t\t\t\t\t\t\t\t<div class=\"price\"><h4><span class=\"woocommerce-Price-amount amount\"><span class=\"woocommerce-Price-currencySymbol\">&euro;<\/span>1,735.00<\/span> + VAT (if applicable)<\/h4><\/div>\n\t\t\t\t\t\t\t\t\t<div class=\"stats\">\n\t\t\t\t\t\t\t\t\t\t<a rel=\"nofollow\" href=\"\/hy\/wp-json\/wp\/v2\/glossary\/255?add-to-cart=4193\" data-quantity=\"1\" data-product_id=\"4193\" data-product_sku=\"BS-1OEM\" class=\"button product_type_simple add_to_cart_button ajax_add_to_cart btn btn-just-icon btn-simple btn-default\" title=\"Add to cart\" data-no-translation-title=\"\"><i rel=\"tooltip\" data-original-title=\"Add to cart\" class=\"fas fa-cart-plus\" data-no-translation-data-original-title=\"\"><\/i><\/a>\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/a><a href=\"\/hy\/wp-json\/wp\/v2\/glossary\/255?add-to-cart=4193\" aria-describedby=\"woocommerce_loop_add_to_cart_link_describedby_4193\" data-quantity=\"1\" class=\"button product_type_simple add_to_cart_button ajax_add_to_cart\" data-product_id=\"4193\" data-product_sku=\"BS-1OEM\" aria-label=\"Add to cart: \u201cDynamic balancer \u201cBalanset-1A\u201d OEM\u201d\" rel=\"nofollow\" data-success_message=\"\u201cDynamic balancer \u201cBalanset-1A\u201d OEM\u201d has been added to your cart\" data-no-translation=\"\" data-trp-gettext=\"\" data-no-translation-aria-label=\"\" data-no-translation-data-success_message=\"\">Add to cart<\/a>\t<span id=\"woocommerce_loop_add_to_cart_link_describedby_4193\" class=\"screen-reader-text\">\n\t\t\t<\/span>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/section>\n\t\t\n<p><strong>Steam whirl<\/strong> \u2014 also called aerodynamic cross-coupling instability or seal whirl \u2014 is a <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/self-excited-vibration\/\">self-excited vibration<\/a> that arises in steam and gas turbines when aerodynamic forces inside labyrinth seals, blade-tip clearances, or other annular passages generate a destabilising tangential force on the <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/rotor\/\">rotor<\/a>. Like <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/oil-whirl\/\">oil whirl<\/a> in hydrodynamic bearings, it is a form of <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/rotor-instability\/\">rotor instability<\/a> in which energy is continuously drawn from the steady flow of steam or gas and converted into orbital motion of the shaft. The result is high-amplitude <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/sub-synchronous\/\">sub-synchronous<\/a> <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/vibration\/\">vibration<\/a> at a frequency close to one of the rotor&#8217;s <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/natural-frequency\/\">natural frequencies<\/a> \u2014 and, if not detected and corrected quickly, it can drive a machine to catastrophic failure.<\/p>\n<h2>1. Physical Mechanism<\/h2>\n<p>Steam whirl is fundamentally a fluid-structure interaction in the narrow clearances of turbine seals. It develops in three linked stages.<\/p>\n<h3>Labyrinth Seal Clearances<\/h3>\n<ul>\n<li>Steam or gas flows through narrow annular passages between rotating and stationary seal components.<\/li>\n<li>A high pressure differential acts across the seals \u2014 often 50\u2013200 bar in large machines.<\/li>\n<li>Radial clearances are tight, typically 0.2\u20130.5 mm.<\/li>\n<li>The flow acquires a swirl, a tangential velocity component, as it passes through the seal teeth.<\/li>\n<\/ul>\n<h3>Aerodynamic Cross-Coupling<\/h3>\n<p>The instability is born the moment the rotor is displaced from its centred position:<\/p>\n<ul>\n<li>The clearance becomes asymmetric \u2014 smaller on one side, larger on the opposite side.<\/li>\n<li>The flow and pressure distribution around the seal turn non-uniform.<\/li>\n<li>The net aerodynamic force gains a <em>tangential<\/em> component, acting perpendicular to the displacement rather than opposing it.<\/li>\n<li>That tangential force behaves like a destabilising &#8220;negative <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/stiffness\/\">stiffness<\/a>&#8220;, pushing the rotor along its orbit instead of back to centre.<\/li>\n<\/ul>\n<h3>Self-Excited Vibration<\/h3>\n<ul>\n<li>The tangential force drives the rotor into a forward <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/whirl\/\">whirl<\/a> orbit.<\/li>\n<li>The orbit frequency settles near a natural frequency, hence sub-synchronous.<\/li>\n<li>Energy is continuously extracted from the steam flow to sustain the motion.<\/li>\n<li>Amplitude grows until limited by the available clearance \u2014 or by failure of the machine.<\/li>\n<\/ul>\n<h2>2. Conditions Promoting Steam Whirl<\/h2>\n<p>Whether a given machine becomes unstable depends on a balance between destabilising seal forces and the available <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/damping\/\">damping<\/a>. Three groups of factors tip that balance.<\/p>\n<h3>Geometric Factors<\/h3>\n<ul>\n<li><strong>Tight seal clearances:<\/strong> smaller clearances produce stronger aerodynamic forces.<\/li>\n<li><strong>Long seal lengths:<\/strong> more seal teeth or longer seal sections increase the destabilising force.<\/li>\n<li><strong>High swirl velocity:<\/strong> flow entering the seal with a large tangential component is especially destabilising.<\/li>\n<li><strong>Large seal diameters:<\/strong> a larger radius amplifies the moment generated by the aerodynamic force.<\/li>\n<\/ul>\n<h3>Operating Conditions<\/h3>\n<ul>\n<li><strong>High pressure differentials:<\/strong> a greater pressure drop across the seal raises the force.<\/li>\n<li><strong>High rotor speed:<\/strong> both centrifugal effects and swirl velocity grow with speed.<\/li>\n<li><strong>Low bearing damping:<\/strong> insufficient damping cannot counteract the seal forces.<\/li>\n<li><strong>Light-load conditions:<\/strong> low bearing loads reduce the effective damping a <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/journal-bearing\/\">journal bearing<\/a> can provide.<\/li>\n<\/ul>\n<h3>Rotor Characteristics<\/h3>\n<ul>\n<li><strong>Flexible rotors:<\/strong> a <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/flexible-rotor\/\">flexible rotor<\/a> running above its <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/critical-speed\/\">critical speeds<\/a> is more susceptible.<\/li>\n<li><strong>Low-damping systems:<\/strong> minimal structural or bearing damping leaves nothing to absorb the energy.<\/li>\n<li><strong>High length-to-diameter ratio:<\/strong> slender rotors are inherently more prone to instability.<\/li>\n<\/ul>\n<h2>3. Diagnostic Characteristics<\/h2>\n<h3>Vibration Signature<\/h3>\n<p>Steam whirl leaves a distinctive pattern that <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/vibration-analysis\/\">vibration analysis<\/a> can identify with confidence:<\/p>\n<table border=\"1\" style=\"width:100%; border-collapse:collapse;\">\n<tr>\n<th>Parameter<\/th>\n<th>Characteristic<\/th>\n<\/tr>\n<tr>\n<td>Frequency<\/td>\n<td>Sub-synchronous, typically 0.3\u20130.6\u00d7 running speed, often locking onto a natural frequency<\/td>\n<\/tr>\n<tr>\n<td>Amplitude<\/td>\n<td>High \u2014 often 5\u201320 times the normal unbalance vibration<\/td>\n<\/tr>\n<tr>\n<td>Onset<\/td>\n<td>Sudden, above a threshold speed or pressure<\/td>\n<\/tr>\n<tr>\n<td>Speed dependence<\/td>\n<td>Frequency may lock and refuse to track with speed changes<\/td>\n<\/tr>\n<tr>\n<td>Orbit<\/td>\n<td>Large circular or elliptical, forward precession<\/td>\n<\/tr>\n<tr>\n<td>Spectrum<\/td>\n<td>Dominant sub-synchronous peak<\/td>\n<\/tr>\n<\/table>\n<h3>Differentiation from Other Instabilities<\/h3>\n<ul>\n<li><strong>vs. oil whirl \/ whip:<\/strong> steam whirl occurs in turbines with labyrinth seals, whereas oil whirl occurs in plain <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/journal-bearing\/\">journal bearings<\/a>.<\/li>\n<li><strong>vs. unbalance:<\/strong> steam whirl is sub-synchronous, while <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/imbalance\/\">unbalance<\/a> is a 1\u00d7 <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/synchronous-vibration\/\">synchronous<\/a> response.<\/li>\n<li><strong>vs. rub:<\/strong> steam whirl can occur without any contact, and its frequency is more stable than the erratic vibration of a <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/rotor-rub\/\">rotor rub<\/a>.<\/li>\n<\/ul>\n<h2>4. Prevention and Mitigation Methods<\/h2>\n<p>Most countermeasures attack one of two targets: reduce the destabilising swirl at source, or add damping so the rotor can absorb it. Seal design tackles the first; bearing improvements and operating limits tackle the second.<\/p>\n<h3>Seal Design Modifications<\/h3>\n<ul>\n<li><strong>Anti-swirl devices (swirl brakes):<\/strong> stationary vanes or baffles placed upstream of the seal strip the tangential velocity out of the incoming flow, sharply reducing the cross-coupling force. This is the most effective and most common solution.<\/li>\n<li><strong>Honeycomb seals:<\/strong> replacing the smooth labyrinth lands with a honeycomb structure generates turbulence that dissipates swirl energy and raises the effective damping in the seal region; widely used in modern gas turbines.<\/li>\n<li><strong>Increased seal clearances:<\/strong> larger radial clearances weaken the aerodynamic force, but at the cost of more leakage and reduced turbine efficiency, so this is usually only a temporary measure.<\/li>\n<li><strong>Damper seals:<\/strong> purpose-designed seals \u2014 pocket damper seals and hole-pattern seals \u2014 that provide damping while still sealing, adding a stabilising force to oppose the cross-coupling.<\/li>\n<\/ul>\n<h3>Bearing System Improvements<\/h3>\n<ul>\n<li><strong>Increase bearing damping:<\/strong> fit tilting-pad bearings or add a <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/squeeze-film-damper\/\">squeeze film damper<\/a>.<\/li>\n<li><strong>Bearing preload:<\/strong> applying <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/preload\/\">preload<\/a> raises both effective stiffness and damping.<\/li>\n<li><strong>Optimised bearing design:<\/strong> selecting the bearing type and configuration for maximum stability margin.<\/li>\n<\/ul>\n<h3>Operational Controls<\/h3>\n<ul>\n<li><strong>Speed restrictions:<\/strong> keep operating speed below the instability threshold.<\/li>\n<li><strong>Load management:<\/strong> avoid light-load running that strips damping from the bearings.<\/li>\n<li><strong>Pressure control:<\/strong> reduce seal pressure differentials where the process allows.<\/li>\n<li><strong>Continuous monitoring:<\/strong> real-time <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/condition-monitoring\/\">condition monitoring<\/a> with dedicated sub-synchronous alarms.<\/li>\n<\/ul>\n<h2>5. Detection and Emergency Response<\/h2>\n<h3>Early Warning Signs<\/h3>\n<ul>\n<li>Small sub-synchronous peaks beginning to appear in the vibration <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/spectrum\/\">spectrum<\/a>.<\/li>\n<li>Intermittent high-frequency components.<\/li>\n<li>A gradual rise in the overall <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/vibration-severity\/\">vibration severity<\/a> as speed approaches the threshold.<\/li>\n<li>Changes in the <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/orbit\/\">orbit<\/a> shape captured by proximity probes.<\/li>\n<\/ul>\n<h3>Immediate Actions When Steam Whirl Is Detected<\/h3>\n<ol>\n<li><strong>Reduce speed:<\/strong> immediately decrease speed below the threshold.<\/li>\n<li><strong>Do not delay:<\/strong> amplitude can grow from acceptable to destructive in 30\u201360 seconds.<\/li>\n<li><strong>Emergency shutdown:<\/strong> trip the machine if a speed reduction is insufficient or impossible.<\/li>\n<li><strong>Document the event:<\/strong> record the speed at onset, the frequency, the peak amplitude, and the operating conditions.<\/li>\n<li><strong>Do not restart:<\/strong> keep the machine down until the root cause is identified and corrected.<\/li>\n<\/ol>\n<h3>Where Field Instruments Fit<\/h3>\n<p>Permanently installed protection systems handle the split-second trip, but a portable two-channel analyser is invaluable for investigating the instability once the machine is stopped and for commissioning checks afterwards. An instrument such as the <a href=\"https:\/\/vibromera.eu\/hy\/product\/balanset-1\/\">Balanset-1A<\/a> captures the FFT spectrum to confirm the sub-synchronous peak, tracks its amplitude during a controlled run-up, and lets an engineer first rule out a 1\u00d7 <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/imbalance\/\">unbalance<\/a> problem \u2014 by measuring amplitude and phase at running speed \u2014 before attributing the vibration to a true self-excited seal instability. Separating an ordinary unbalance, which <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/field-balancing\/\">field balancing<\/a> can cure, from genuine steam whirl, which it cannot, is a critical early diagnostic step.<\/p>\n<h2>6. Industries, Applications, and Related Phenomena<\/h2>\n<p>Steam whirl is of particular concern in:<\/p>\n<ul>\n<li><strong>Power generation:<\/strong> large steam turbine-generators.<\/li>\n<li><strong>Petrochemical:<\/strong> steam-driven compressors and pumps.<\/li>\n<li><strong>Gas turbines:<\/strong> aircraft engines and industrial gas turbines.<\/li>\n<li><strong>Process industries:<\/strong> any high-speed turbomachinery fitted with labyrinth seals.<\/li>\n<\/ul>\n<p>It also sits within a family of closely related instabilities. <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/oil-whirl\/\">Oil whirl<\/a> shares the same destabilising mechanism but in a bearing oil film rather than a seal; <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/shaft-whip\/\">shaft whip<\/a> exhibits the same frequency lock-in at a natural frequency; and all of them are members of the broader category of self-excited <a href=\"https:\/\/vibromera.eu\/hy\/glossary\/rotor-instability\/\">rotor instability<\/a>. While advances in seal technology and bearing design have reduced how often it appears, understanding steam whirl remains essential for anyone engineering or operating high-speed, high-pressure turbomachinery.<\/p>\n<hr>\n<p><a href=\"https:\/\/vibromera.eu\/hy\/glossary\/\">\u2190 Back to Main Index<\/a><\/p>","protected":false},"excerpt":{"rendered":"<p>Learn about steam whirl, a self-excited vibration instability in steam turbines caused by aerodynamic cross-coupling forces in labyrinth seals and blade tip clearances.<\/p>","protected":false},"featured_media":0,"template":"","meta":{"ai_generated_summary":"","footnotes":""},"categories":[109,110],"tags":[],"class_list":["post-255","glossary","type-glossary","status-publish","hentry","category-glossary","category-vibration-diagnostics"],"_links":{"self":[{"href":"https:\/\/vibromera.eu\/hy\/wp-json\/wp\/v2\/glossary\/255","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/vibromera.eu\/hy\/wp-json\/wp\/v2\/glossary"}],"about":[{"href":"https:\/\/vibromera.eu\/hy\/wp-json\/wp\/v2\/types\/glossary"}],"version-history":[{"count":1,"href":"https:\/\/vibromera.eu\/hy\/wp-json\/wp\/v2\/glossary\/255\/revisions"}],"predecessor-version":[{"id":101413,"href":"https:\/\/vibromera.eu\/hy\/wp-json\/wp\/v2\/glossary\/255\/revisions\/101413"}],"wp:attachment":[{"href":"https:\/\/vibromera.eu\/hy\/wp-json\/wp\/v2\/media?parent=255"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vibromera.eu\/hy\/wp-json\/wp\/v2\/categories?post=255"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vibromera.eu\/hy\/wp-json\/wp\/v2\/tags?post=255"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}