Intelligent coaxial square rail double laser deicing method for offshore wind turbine

Abstract

The present application relates to the technical field of fan equipment maintenance and deicing, and particularly relates to a kind of offshore wind turbine intelligent coaxial square rail double laser deicing methods.In the parameter acquisition link, the effective density, effective specific heat capacity and real-time updated convective heat transfer coefficient of ice layer are calculated by radar and laser positioning and ice condition judgment of ice layer;In the power calculation link, the energy required for ice melting and the energy loss of convective heat transfer are calculated according to the parameters obtained in the parameter acquisition link, and the power and action time of short-wave laser are calculated accordingly, and the action time of short-wave laser is used as the action time of long-wave laser, and the power of long-wave laser is calculated according to the action time of long-wave laser;In the deicing implementation stage, the laser emitter emits short-wave laser and long-wave laser to the ice surface according to the strategy parameters for deicing.The present application realizes efficient penetration and melting by regulating laser power, and achieves the purpose of precise, efficient and low-energy consumption wind turbine blade deicing by combining the scheme of long and short wave laser alternating and stacking operation.

Description

Technical Field

[0001] This invention relates to the technical field of wind turbine equipment maintenance and de-icing, and in particular to an intelligent coaxial square rail dual-laser de-icing method for offshore wind turbines. Background Technology

[0002] Offshore wind turbine blades are the core components that capture ocean wind energy and convert kinetic energy into electrical energy. However, in the low-temperature, high-humidity, and high-salinity offshore wind environment, the blade surface is extremely prone to icing or the accumulation of salt frost and ice. Offshore winds are typically characterized by high wind speeds, strong turbulence, and the carrying of large amounts of salt spray, which exacerbates the blade icing process and presents unique challenges: icing severely disrupts the aerodynamic shape of the blades, reducing wind capture efficiency; simultaneously, the superposition of uneven icing and the enormous aerodynamic loads from strong offshore winds significantly increases the structural stress on the blades, triggering abnormal vibrations. Long-term operation will severely damage the main blade structure, bearings, and transmission system, and may even lead to major accidents such as blade breakage. Therefore, solving the blade icing problem under the special wind conditions at sea is of crucial practical significance for ensuring the safe, stable, and efficient operation of offshore wind farms.

[0003] Currently, de-icing technologies applied to offshore wind turbine blades can be divided into two categories: active de-icing and passive de-icing. Active de-icing technology includes various approaches such as built-in electrothermal de-icing systems and hot air de-icing systems. Built-in electrothermal de-icing systems require the installation of electrothermal elements inside the wind turbine blades, consuming electrical energy to raise the blade temperature and achieve de-icing. For example, Chinese patent application 2025117586140 discloses a "Wind Turbine De-icing System, Method, Electronic Equipment, and Storage Medium" (application publication number CN121205887A). This system includes: a heating module, laid on the blade surface and divided into multiple heating zones, each zone being independently controlled to provide localized heating; a monitoring module, used to detect and output the icing thickness and environmental parameters of the blades; and a control module, communicatively connected to the monitoring and heating modules, used to dynamically adjust the power of the heating zones based on the icing thickness and environmental parameters, and to achieve de-icing control through an icing prediction model. Electric heating de-icing systems consume a large amount of electricity, significantly depleting the wind turbine's own power generation. The heating elements embedded within the blades may alter the original lightning discharge path, potentially causing damage from lightning strikes. They are also prone to localized overheating, impacting blade lifespan. Hot air de-icing systems also require significant electrical energy to generate hot air and necessitate complex hot air ductwork. Composite materials exhibit slow heat transfer and delayed response, leading to uneven ice melting and potential load risks. Furthermore, the built-in ductwork increases weight and design complexity, and requires additional energy for heating when the wind turbine is shut down. Passive de-icing technology utilizes low surface energy interfaces on the blade surface to suppress water droplet wetting and reduce ice adhesion strength. For example, Chinese patent application 2025115089800 discloses "A Blade De-icing Structure, Composite Icing Coating and its Preparation Method," publication number CN121293860A. The preparation method of this composite anti-icing coating involves dispersing silica nanoparticles in an organic solvent to form a nanoparticle dispersion with a concentration of 110 wt%. Subsequently, a low surface energy resin and a curing agent are added to the nanoparticle dispersion, followed by treatment under ultrasonic conditions in an ice-water bath to obtain the composite anti-icing coating. This passive anti-icing method achieves the purpose of preventing icing by coating a hydrophobic coating on the blade surface. However, its core drawback is that the harsh marine environment easily leads to rapid degradation of the coating surface, and the anti-icing performance typically declines significantly within 6-24 months. In addition, this technology has limited effectiveness against wet snow and strongly adhered ice, and recoating at sea after failure is difficult and costly, resulting in low feasibility for long-term maintenance.

[0004] The principle of laser de-icing technology is to use the thermal energy generated by high-energy lasers to melt the ice. Specifically, when a laser beam strikes the ice layer, the light energy is absorbed by the ice and converted into heat energy, thus melting the ice. Laser de-icing technology is applied in fields such as wind power generation and power transmission. For example, Chinese patent 2025108146067 discloses "A UAV Collaborative Inspection Laser De-icing System and Method," authorized announcement number CN120608832B. Its main control UAV is equipped with a binocular camera for taking pictures and a lidar for ranging to construct a three-dimensional map of the icing on the blades. The UAV is equipped with a pulsed laser generator for heating the ice layer and a thermal infrared camera. The thermal infrared camera is used to collect the temperature field of the blade surface in real time. This de-icing system uses the UAV to achieve three-dimensional modeling of the icing area and collect the blade surface temperature, and uses the pulsed laser generator on the UAV to heat the ice layer to achieve the purpose of de-icing. However, this de-icing method only controls the working state of the pulsed laser generator based on the thickness and temperature of the ice layer, and cannot adapt to the special characteristics of porous sea fog ice formed in the high-humidity marine environment. High humidity and salt spray result in strong ice adhesion and complex thermal conductivity, obstructing heat conduction paths and requiring heat to penetrate the ice layer to be effective. This leads to slow system response and further increases in energy consumption. Strong offshore winds continuously carry away heat from the blade surface, exacerbating heat convection losses and causing a significant amount of electrical energy to dissipate into the environment rather than be effectively used for de-icing. The system needs to maintain high power continuously to cope with frequent freezing rain and sea fog icing processes at sea, resulting in persistently high energy consumption over the long term, significantly impacting power generation revenue and causing low de-icing efficiency and poor performance. To effectively remove ice from offshore wind turbines, it is necessary to comprehensively consider factors such as ice porosity and sea fog salinity to determine the laser power, ensuring efficient and low-energy de-icing without damaging the blades. Summary of the Invention

[0005] To address the aforementioned technical problems, the purpose of this invention is to provide an intelligent coaxial square rail dual-laser de-icing method for offshore wind turbines. Targeting the porous sea fog ice formed in the high-humidity marine environment, characterized by high porosity, loose structure, but strong adhesion, an adaptive energy control strategy matching the porosity characteristics of the sea fog ice is established. By adjusting the laser power, efficient penetration and melting are achieved, resulting in precise and efficient de-icing.

[0006] The present invention discloses an intelligent coaxial square rail dual-laser de-icing method for offshore wind turbines, comprising the following steps: Step 1: Parameter acquisition. After locating the ice layer and judging the ice condition using radar and laser, we obtain the porosity, salinity, wind speed, air density, ice density, and ice thickness of the ice layer. We then calculate the effective density, effective specific heat capacity, and real-time updated convective heat transfer coefficient of the ice layer. Step 2: Power Calculation. Based on the parameters obtained in Step 1, the energy required for ice melting and the energy lost through convective heat transfer are calculated. The sum of the energy required for ice melting and the energy lost through convective heat transfer over the area covered by the short-wavelength laser spot is taken as the effective laser energy of the short-wavelength melting segment. Based on the effective laser energy of the short-wavelength melting segment and the area of ​​the laser spot, the corresponding power and duration of the short-wavelength laser can be calculated. The duration of the short-wavelength laser action is taken as the duration of the long-wavelength laser action, and the power of the long-wavelength laser is calculated based on the duration of the long-wavelength laser action. Step 3: In the de-icing implementation stage, the power and duration of the short-wave laser, the power and duration of the long-wave laser, and the motion trajectories of the short-wave and long-wave laser spots are used as strategy parameters. These strategy parameters are sent to the dual-band coaxial laser emitter. The dual-band coaxial laser emitter emits short-wave and long-wave lasers onto the ice surface according to the strategy parameters to perform de-icing. The long-wave laser spot projected onto the ice surface moves in a circular motion around the short-wave laser spot.

[0007] In step three, the short-wave laser spot's trajectory passes through multiple action points sequentially. The distance between two adjacent action points is 1-2 times the diameter of the short-wave laser spot. The time the short-wave laser spot stays at each action point is the short-wave laser action time. The long-wave laser spot's trajectory is a closed circular or square trajectory centered on the action point surrounding the short-wave laser spot. The time it takes for the long-wave laser spot to complete one revolution is the long-wave laser action duration.

[0008] In step one, The effective density of the ice layer can be calculated using the following formula: ,in In the formula, Effective density; air density; The density of the ice covering; Salinity; Porosity; The effective specific heat capacity of ice can be calculated using the following formula: In the formula, For effective specific heat capacity; The specific heat capacity of salt-containing ice; air density; Porosity; The effective thermal conductivity of ice can be calculated using the following formula: In the formula, Effective thermal conductivity; The thermal conductivity of the ice covering is denoted as α. The thermal conductivity of air; Porosity; The effective convective heat transfer coefficient of the ice layer can be calculated using the following formula: In the formula, The convective heat transfer coefficient between the ice surface and the outside environment at the current ambient temperature; The effective convective heat transfer coefficient.

[0009] In step two, the effective laser energy of the short-wave melting segment is calculated using the following formula: In the formula, The effective laser energy of the short-wave melting section of the effective volume heat source is the sum of the energy required for ice melting and the energy lost through convective heat transfer. For effective convective heat transfer coefficient; The transient temperature of the ice surface. The ambient temperature.

[0010] The power of the short-wavelength laser can be calculated using the following formula: In the formula, This refers to the power of the short-wavelength laser. The effective laser energy of the shortwave melting section of the effective volume heat source; The effective absorption coefficient of the ice layer. Effective reflectivity; Let (x, y) be the radius of the light spot, (x, y) be the coordinates of the shortwave light spot, and (x0, y0) be the origin of the shortwave light spot coordinates. This represents the thickness of the ice layer.

[0011] The action time of the short-wavelength laser can be calculated using the following formula: In the formula, The effective density of the ice layer; The effective specific heat capacity of the ice layer; For shortwave laser energy utilization; For short-wavelength laser power, ; This refers to the duration of shortwave activity. The effective heat exchange area is the area of ​​the contact surface melted by the short-wave laser. This represents the critical thickness at which the ice layer can detach.

[0012] The long-wave power is calculated using the following formula: In the formula, This refers to the power of long-wavelength lasers. For long-wavelength laser energy utilization; The effective specific heat capacity of the ice layer; To effectively melt latent heat, To effectively vaporize latent heat; This refers to the duration of long-wave action; The area covered by the long-wavelength light spot trajectory; The long-wave cutting thickness is the difference between the ice layer thickness and the short-wave melting thickness. , Take 0.02m; The melting temperature. The ambient temperature.

[0013] The effective latent heat of melting of ice can be calculated using the following formula. : In the formula, To effectively melt latent heat; Salinity.

[0014] By adopting the above-mentioned technical solution, this invention establishes an adaptive energy control strategy that matches the porosity characteristics of sea fog ice, which is characterized by high porosity, loose structure, but strong adhesion, formed in high-humidity marine environments. By adjusting the laser power, efficient penetration and melting are achieved. Combined with the scheme of alternating layering of long and short wave lasers, the goal of precise, efficient, and low-energy de-icing of wind turbine blades is achieved. Attached Figure Description

[0015] To more clearly illustrate the technical solution of the present invention, the accompanying drawings used in the description will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the motion trajectories of the short-wavelength laser spot and the long-wavelength laser spot described in this invention.

[0017] Figure 2 This is a three-dimensional structural diagram of the dual-band coaxial laser emitter described in this invention. Detailed Implementation

[0018] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this patent, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this patent.

[0019] The present invention discloses an intelligent coaxial square rail dual-laser de-icing method for offshore wind turbines, comprising the following steps: Step 1: Parameter Acquisition. After locating the ice layer and assessing its condition using radar and laser, the porosity, salinity, wind speed, air density, and ice thickness of the ice layer are obtained. The effective density, effective specific heat capacity, and real-time updated convective heat transfer coefficient of the ice layer are then calculated. Porosity refers to the proportion of pores in the volume of the ice covering the wind turbine blades. Different types of ice exhibit significant differences in porosity, primarily influenced by formation conditions, temperature, salinity, and ice age. Commonly used calculation formulas include… Represents porosity. Salinity, or salt content, refers to the proportion of salt by weight in ice; it is commonly used in calculation formulas. Salinity is represented by g / kg. Air density refers to the mass of a unit volume of air, and is usually calculated using the formula... This represents air density, and its unit is kilograms per cubic meter (kg / m³). 3 ).

[0020] In this step, the effective density of the ice layer is calculated using the following formula. ,in In the formula, Effective density, its unit is kilograms per cubic meter (kg / m³) 3 ); Air density, measured in kilograms per cubic meter (kg / m³) 3 ); The density of icing refers to the density of the ice layer covering the wind turbine blades, and its unit is kilograms per cubic meter (kg / m³). 3 ); Salinity, or salt content, is measured in g / kg. Porosity.

[0021] The effective specific heat capacity of ice can be calculated using the following formula: In the formula, Effective specific heat capacity is expressed in joules per kilogram per kelvin (J / kg). ); The specific heat capacity of salt-containing ice is expressed in joules per kilogram per kelvin (kJ / kg). ); air density; Porosity.

[0022] The effective thermal conductivity of ice can be calculated using the following formula: In the formula, Effective thermal conductivity; The thermal conductivity of ice is a measure of the thermal conductivity of ice, and its unit is watts per meter per Kelvin (W / m). The thermal conductivity of the ice can be calculated from the salinity of the ice. The thermal conductivity of air is expressed in watts per meter per Kelvin (W / m). The thermal conductivity of air can be calculated based on the density and humidity of the air. Porosity.

[0023] The effective convective heat transfer coefficient of the ice layer can be calculated using the following formula: In the formula, The convective heat transfer coefficient between the ice surface and the outside environment at the current ambient temperature; The effective convective heat transfer coefficient.

[0024] Step Two: Power Calculation. Based on the parameters obtained in Step One, the energy required for ice melting and the energy lost through convective heat transfer are calculated. Given a fixed ice density, thickness, salinity, and other ice conditions, the energy required for ice melting depends only on the area of ​​the ice. The sum of the energy required for ice melting and the energy lost through convective heat transfer is taken as the effective laser energy for the short-wave melting segment. The short-wave laser spot remains at the same position for a certain period, and the output of the effective laser energy of the short-wave melting segment is sufficient to melt and remove the ice at that spot. The power and duration of the short-wave laser are calculated based on the effective laser energy of the short-wave melting segment. The duration of the short-wave laser action is taken as the duration of the long-wave laser action, and the power of the long-wave laser is calculated based on the duration of the long-wave laser action.

[0025] The aforementioned short-wavelength lasers selected the 500-1100 nm band, typically using an 808 nm near-infrared laser. This band has high transmittance in ice, allowing it to penetrate the ice layer and reach the ice-blade contact surface to achieve interfacial melting and debonding. In the experiment, the output power was mainly controlled at 5-10 W, the spot diameter at 2-3 mm, and the interaction time at 1-3 s. The long-wavelength lasers selected the 2-11 μm band, typically using a 10.6 μm CO2 laser. This band has high absorption on the ice surface and shallow penetration, enabling high-power melting, vaporization, and cutting. The output power was mainly controlled at 50-100 W, the spot diameter at 1.5-2.5 mm, and the interaction time was consistent with that of the short-wavelength lasers. The wavelength determines the interaction mechanism between laser and ice, which in turn affects the required energy and power, but does not change the basic energy-power-time calculation relationship. Within the recommended typical wavelength range, the interaction law between laser and ice has good consistency and analogy. Therefore, the dual-wavelength synergistic de-icing mechanism, parameter design method and experimental conclusions derived in this scheme have strong applicability and scalability within this wavelength band.

[0026] In this step, the effective laser energy of the short-wave melting segment is calculated using the following formula: In the formula, The effective laser energy of the short-wave melting section of the effective volume heat source is the sum of the energy required for ice melting and the energy lost through convective heat transfer. For effective convective heat transfer coefficient; The transient temperature of the ice surface. The ambient temperature.

[0027] The power of the short-wavelength laser can be calculated using the following formula: In the formula, This refers to the power of the short-wavelength laser. The effective laser energy of the shortwave melting section of the effective volume heat source; The effective absorption coefficient of the ice layer. Effective reflectivity; Let (x, y) be the radius of the light spot, (x, y) be the coordinates of the shortwave light spot, and (x0, y0) be the origin of the shortwave light spot coordinates. This represents the thickness of the ice layer.

[0028] The action time of short-wavelength laser light can be calculated using the following formula: In the formula, The effective density of the ice layer; The effective specific heat capacity of the ice layer; For shortwave laser energy utilization; For short-wavelength laser power, ; This refers to the duration of shortwave activity. The effective heat exchange area is the area of ​​the contact surface melted by the short-wave laser. This represents the critical thickness at which the ice layer can detach.

[0029] The long-wave power is calculated using the following formula: In the formula, This refers to the power of long-wavelength lasers. For long-wavelength laser energy utilization; The effective specific heat capacity of the ice layer; To effectively melt latent heat, To effectively vaporize latent heat; This refers to the duration of long-wave action; The area covered by the long-wavelength light spot trajectory; The long-wave cutting thickness is the difference between the ice layer thickness and the short-wave melting thickness. , Take 0.02m; The melting temperature. The ambient temperature.

[0030] The effective latent heat of melting of ice can be calculated using the following formula. : In the formula, To effectively melt latent heat; Salinity.

[0031] Step 3: In the de-icing implementation stage, the power and duration of the short-wave laser, the power and duration of the long-wave laser, and the motion trajectories of the short-wave and long-wave laser spots are used as strategy parameters. These strategy parameters are sent to the dual-band coaxial laser emitter. The dual-band coaxial laser emitter emits short-wave and long-wave lasers onto the ice surface according to the strategy parameters to perform de-icing. The long-wave laser spot projected onto the ice surface moves in a circular motion around the short-wave laser spot.

[0032] In this step, multiple action points are evenly spaced across the wind turbine blade area to be de-iced. The trajectory of the short-wave laser spot passes sequentially through these multiple action points. The distance between adjacent action points is 1-2 times the diameter of the short-wave laser spot. The dwell time of the short-wave laser spot at each action point is the short-wave laser action time. Figure 1 As shown, the trajectory of the long-wavelength laser spot is a closed circular or square trajectory that surrounds the short-wavelength laser spot with the point of action as the center. The time it takes for the long-wavelength laser spot to complete one revolution is the duration of the long-wavelength laser action.

[0033] like Figure 2 As shown, the center of the dual-band coaxial laser emitter is a short-wave laser head 11, and a square or circular track 3 is arranged around the short-wave laser head 11. A long-wave laser head 22 is installed on the track 3, and the long-wave laser head 22 can move in a circle around the short-wave laser head 11 along the track 3.

[0034] As described above, during the de-icing phase, the dual-band coaxial laser emitter operates according to its strategy parameters. The short-wave laser spot releases sufficient energy during its dwell time at each target point to melt the ice at that point. Simultaneously, within the same time period, the long-wave laser head 22 emits a long-wave laser spot that orbits the short-wave laser spot, releasing sufficient energy to melt the ice within a certain width around the target point. This process continues, and within one action period, the combined action of the short-wave and long-wave laser spots can melt and remove ice from a sufficiently large area around a target point. Subsequently, the dual-band coaxial laser emitter focuses on another target point and operates according to the same strategy parameters, performing de-icing operations point by point until the entire blade is de-iced.

[0035] Table 1 Experimental parameters for different surfaces Note: The following data is based on Vestas 2.5MW wind turbine blades, with an ice thickness of 3cm and a de-icing time of 2 hours. Table 2. Power Comparison of Four De-icing Methods (Taking a 3cm Thick Ice Layer as an Example) Table 3. Dual-laser de-icing parameters Table 4. Energy Consumption Comparison of Two Laser De-icing Methods under Different Ice Thicknesses within 2 Hours Traditional laser de-icing requires melting the entire ice layer, and the laser power increases sharply with the thickness of the ice layer. This dual-wavelength scheme melts only the bottom thin layer and is supplemented by ice cutting, resulting in a gradual increase in power.

[0036] The thicker the ice layer, the more significant the energy-saving advantage of this solution compared to traditional lasers, demonstrating clear engineering and energy-saving advantages.

[0037] Notes: 1. The salinity is supplemented with reference to the common salinity range of sea fog ice (3.3‰-3.6‰) to match actual working conditions; 2. The laser frequency selected is the commonly used patented 1064nm short wave (corresponding frequency 1064Hz) and 10.6μm long wave (corresponding frequency 10.6×10⁻⁶Hz). 31. The energy loss due to convective heat transfer is calculated based on the effective convective heat transfer coefficient, temperature difference, and calculated area, ensuring the data is rigorous. 2. All parameters are consistent with the experimental data of the supporting materials and can be directly used to support the patent implementation examples.

Claims

1. A method for intelligent coaxial square rail dual-laser de-icing of offshore wind turbines, characterized in that, Includes the following steps, Step 1: Parameter acquisition. After locating the ice layer and judging the ice condition using radar and laser, we obtain the porosity, salinity, wind speed, air density, ice density, and ice thickness of the ice layer. We then calculate the effective density, effective specific heat capacity, and real-time updated convective heat transfer coefficient of the ice layer. Step 2: Power Calculation. Based on the parameters obtained in Step 1, the energy required for ice melting and the energy lost through convection heat transfer are calculated. The sum of the energy required for ice melting and the energy lost through convection heat transfer is taken as the effective laser energy of the short-wave melting segment. The power and duration of the short-wave laser are calculated based on the effective laser energy of the short-wave melting segment. The duration of the short-wave laser is taken as the duration of the long-wave laser, and the power of the long-wave laser is calculated based on the duration of the long-wave laser. Step 3: In the de-icing implementation stage, the power and duration of the short-wave laser, the power and duration of the long-wave laser, and the motion trajectories of the short-wave and long-wave laser spots are used as strategy parameters. These strategy parameters are sent to the dual-band coaxial laser emitter. The dual-band coaxial laser emitter emits short-wave and long-wave lasers onto the ice surface according to the strategy parameters to perform de-icing. The long-wave laser spot projected onto the ice surface moves in a circular motion around the short-wave laser spot.

2. The intelligent coaxial square rail dual-laser de-icing method for offshore wind turbines according to claim 1, characterized in that: In step three, the short-wave laser spot's trajectory passes through multiple action points sequentially. The distance between two adjacent action points is 1-2 times the diameter of the short-wave laser spot. The time the short-wave laser spot stays at each action point is the short-wave laser action time. The long-wave laser spot's trajectory is a closed circular or square trajectory centered on the action point surrounding the short-wave laser spot. The time it takes for the long-wave laser spot to complete one revolution is the long-wave laser action duration.

3. The intelligent coaxial square rail dual-laser de-icing method for offshore wind turbines according to claim 1 or 2, characterized in that: In step one, The effective density of the ice layer can be calculated using the following formula: ,in In the formula, Effective density; air density; The density of the ice covering; Salinity; Porosity; The effective specific heat capacity of ice can be calculated using the following formula: In the formula, For effective specific heat capacity; The specific heat capacity of salt-containing ice; air density; Porosity; The effective thermal conductivity of ice can be calculated using the following formula: In the formula, Effective thermal conductivity; The thermal conductivity of the ice covering is denoted as α. The thermal conductivity of air; Porosity; The effective convective heat transfer coefficient of the ice layer can be calculated using the following formula: In the formula, The convective heat transfer coefficient between the ice surface and the outside environment at the current ambient temperature; The effective convective heat transfer coefficient.

4. The intelligent coaxial square rail dual-laser de-icing method for offshore wind turbines according to claim 1 or 2, characterized in that: In step two, the effective laser energy of the short-wave melting segment is calculated using the following formula: In the formula, The effective laser energy of the short-wave melting section of the effective volume heat source is the sum of the energy required for ice melting and the energy lost through convective heat transfer. For effective convective heat transfer coefficient; The transient temperature of the ice surface. The ambient temperature.

5. The power of the short-wavelength laser can be calculated using the following formula: In the formula, This refers to the power of the short-wavelength laser. The effective laser energy of the shortwave melting section of the effective volume heat source; The effective absorption coefficient of the ice layer. Effective reflectivity; Let (x, y) be the radius of the light spot, (x, y) be the coordinates of the shortwave light spot, and (x0, y0) be the origin of the shortwave light spot coordinates. This represents the thickness of the ice layer.

6. The action time of short-wavelength laser light can be calculated using the following formula: In the formula, The effective density of the ice layer; The effective specific heat capacity of the ice layer; For shortwave laser energy utilization; For short-wavelength laser power, ; This refers to the duration of shortwave activity. The effective heat exchange area is the area of ​​the contact surface melted by the short-wave laser. This represents the critical thickness at which the ice layer can detach.

7. The long-wave power can be calculated using the following formula: In the formula, This refers to the power of long-wavelength lasers. For long-wavelength laser energy utilization; The effective specific heat capacity of the ice layer; To effectively melt latent heat, To effectively vaporize latent heat; This refers to the duration of long-wave action; The area covered by the long-wavelength light spot trajectory; The long-wave cutting thickness is the difference between the ice layer thickness and the short-wave melting thickness. , Take 0.02m; The melting temperature. The ambient temperature.

8. Calculate the effective latent heat of melting of ice using the following formula. : In the formula, To effectively melt latent heat; Salinity.

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