Safety spacing analysis method and system for ship navigation in navigation tunnel

Abstract

The invention belongs to the technical field of shipping, and particularly relates to a method and system for determining the dynamic safety distance between ships in a navigation tunnel. The method comprises the steps of obtaining dynamic parameters of ships in a navigable tunnel; calculating a basic safety distance according to the dynamic parameters; correcting the basic safety interval based on the emergency scene type to generate an emergency scene safety interval; performing adaptive adjustment on the emergency scene safety distance by combining the tunnel environment parameters, and outputting a final safety distance; and generating a ship sailing distance control instruction according to the final safety distance. According to the method, through layer-by-layer correction of dynamic parameters and emergency scenes and combination of tunnel environment adaptive adjustment, dynamic optimization of the ship safety spacing in a complex navigable tunnel scene is realized, the limitation of a traditional static spacing rule in environment sudden change and multi-risk superposition scenes is overcome, and the safety of the ship safety spacing in the complex navigable tunnel scene is improved. And the ship navigation safety and the tunnel operation efficiency are effectively improved.

Description

Technical Field

[0001] The present invention relates to the field of shipping technology, and in particular to a method and system for analyzing safe spacing for ships sailing in a navigation tunnel. Background Art

[0002] Navigation tunnels serve as critical passages for ships traversing complex terrain, such as mountains and dams. Their internal navigation environment is constrained by factors such as enclosed spaces, turbulent water flows, and low visibility. Accurately controlling safe spacing between ships directly impacts navigation efficiency and accident risk. Existing technologies often set safe spacing based on static parameters (such as ship size and fixed speed) or empirical values ​​for single emergency scenarios. This lacks comprehensive analysis of dynamic navigation parameters and complex tunnel environments, resulting in calculations that are insufficiently compatible with actual risk scenarios. Therefore, a safe spacing analysis method is urgently needed to improve the reliability and flexibility of ship spacing control in complex tunnel scenarios. Summary of the Invention

[0003] In order to solve the above technical problems, the present invention provides a method and system for analyzing the safe distance of ships sailing in a navigation tunnel.

[0004] In a first aspect, the present invention provides a method for analyzing safe distances for ships navigating in a navigation tunnel, comprising: S1. Obtain dynamic parameters of ships in a navigation tunnel; S2. Calculate the basic safety distance according to the dynamic parameters; S3. Modify the basic safety distance according to the type of emergency scenario in the navigation tunnel to generate an emergency scenario safety distance; S4. Adapt and adjust the emergency scenario safety distance according to the tunnel environmental parameters and output a final safety distance; S5. Outputting navigation spacing control instructions for ships in the navigation tunnel based on the final safety spacing.

[0005] Optionally, The tunnel environmental parameters include tunnel section coefficient, tunnel width, total tunnel length, real-time water depth, visibility and discharge flow; The dynamic parameters include ship speed, ship width, ship braking performance, ship wave propagation distance and ship sinking amount; The ship's braking performance includes braking reaction time and braking acceleration; The ship wave propagation distance is calculated based on the ship speed, the real-time water depth and the tunnel section coefficient.

[0006] Optionally, the basic safety distance includes a weighted combination of braking distance, ship wave propagation distance and ship sinking amount; The calculation formula of the braking distance is: ; Among them, D b is the braking distance, V is the ship speed, t r is the braking reaction time, is the braking acceleration; The calculation formula for the ship wave propagation distance is: ; Among them, L w is the propagation distance of the ship wave, k is the tunnel section coefficient, V is the ship speed, and h is the real-time water depth.

[0007] Optionally, the S3 specifically includes: According to the type of emergency scenario in the navigation tunnel, the emergency evacuation distance is superimposed on the basic safety distance to generate the emergency scenario safety distance; The calculation formula for the emergency evacuation distance is: ; Among them, D e is the emergency evacuation distance, V vis is the visibility, t escape is the preset personnel evacuation time, and t0 is the reference time constant.

[0008] Optionally, the S4 specifically includes: When the ratio of the tunnel width to the ship width is less than a preset threshold, the correction formula for the final safety distance is: ; in, is the final safety distance, The safety distance for the emergency scenario is is the width of the ship, is the tunnel width.

[0009] Optionally, when applied to a dam lock through section, the final safety distance is superimposed with a water flow disturbance correction term, and the calculation formula of the water flow disturbance correction term is: ; Among them, D fl is the water disturbance correction term, β is the water disturbance coefficient, and Q is the discharge flow.

[0010] Optionally, when applied to a long tunnel crossing a mountain range, the braking reaction time is modified to: ; in, is the corrected braking reaction time, is the braking reaction time before correction, is the total length of the tunnel, For the visibility.

[0011] Optionally, when applied to mixed-vessel scenarios, the formula for setting the safety redundancy coefficients of cargo ships and passenger ships is as follows: ; ; ; Among them, α cargo is the safety redundancy factor of the cargo ship, α passenger is the safety redundancy coefficient of the passenger ship, γ is the difference coefficient, D safe,cargo is the basic safety distance of cargo ships, D safe,passenger is the basic safety distance of the passenger ship, and S is the sinking amount of the ship.

[0012] In a second aspect, the present invention further provides a safe distance analysis system for ships sailing in a navigation tunnel, comprising: An acquisition module is used to obtain dynamic parameters of ships in the navigation tunnel; A calculation module, configured to calculate a basic safety distance according to the dynamic parameters; A correction module, configured to correct the basic safety distance according to the type of emergency scenario in the navigation tunnel to generate an emergency scenario safety distance; An adaptation module, configured to adapt and adjust the emergency scenario safety distance according to tunnel environmental parameters and output a final safety distance; An output module is used to output a navigation spacing control instruction for ships in the navigation tunnel based on the final safety spacing.

[0013] The present invention has the following technical effects: The present invention provides a dynamic analysis method and system for the safe distance between ships in a navigable tunnel. By acquiring the dynamic parameters of the ship during navigation in real time, combined with the tunnel environment characteristics and the needs of sudden emergency scenarios, the flexible calculation and dynamic optimization of the safe distance are realized. Traditional methods usually rely on fixed empirical values ​​or single parameter calculations, which are difficult to adapt to the complex and changeable environment and sudden risks in the tunnel. The present invention uses a hierarchical and progressive correction logic to first calculate the basic safe distance based on dynamic parameters such as ship speed and braking performance, and then superimpose additional safety redundancy for different emergency scenarios. Finally, it is fine-tuned in combination with the structural characteristics of the tunnel, so that the safe distance can meet the physical needs of emergency braking of ships and adapt to the special requirements of different environmental conditions and emergencies. This hierarchical adjustment strategy effectively solves the problem of dynamic adaptation of ship spacing control in closed tunnels, avoids safety hazards caused by sudden environmental changes or insufficient emergency response, and takes into account the stability of navigation efficiency.

[0014] Further improvements, such as the amount of ship sinking and the distance of ship-borne wave propagation, allow the calculation of basic safety clearances to more accurately reflect the actual navigational conditions of ships. For example, the calculation of ship-borne wave propagation distance incorporates the interaction between ship speed and tunnel cross-section, avoiding the risk of collision due to wave superposition. Addressing the specific environments of different tunnel sections, such as dynamic adjustment of clearance by the ratio of tunnel width to ship width in narrow sections, visibility-based braking response time correction in long tunnels crossing mountainous terrain, and disturbance compensation by superimposing discharge flow in dam and lock sections, further enhances the accuracy of clearance control in specific scenarios. For mixed-vessel scenarios, differentiated safety redundancy factors are set for cargo and passenger ships, ensuring the high safety requirements of passenger ships while avoiding the waste of navigation resources caused by excessive redundancy in cargo ships. These improvements, through refined parameter classification and scenario adaptation rules, form a multi-dimensional, multi-level optimization system within an overall framework, significantly enhancing the practicality and reliability of the method. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0016] Figure 1 A schematic flow chart of a method for analyzing safe spacing for ships sailing in a navigation tunnel provided by an embodiment of the present invention; Figure 2 A schematic diagram of the structure of a safety distance analysis system for ships navigating in a navigation tunnel provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0017] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention are described clearly and completely below. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are also within the scope of protection of the present invention.

[0018] Figure 1 A schematic flow chart of a method for analyzing safe spacing for ships in a navigation tunnel provided in an embodiment of the present invention includes: S1. Obtain dynamic parameters of ships in a navigation tunnel; When analyzing safe distances between ships in a navigation tunnel, it's first necessary to capture dynamic parameters generated during navigation. These parameters reflect the ship's real-time status and movement trends. Dynamic parameters include the ship's own attributes as well as navigation-related performance indicators, such as the ship's speed within the tunnel and changes in braking capacity. The collection of dynamic parameters provides basic data support for subsequent calculations, ensuring the real-time and accurate safety distance analysis.

[0019] S2. Calculate the foundation safety distance based on dynamic parameters; When calculating the basic safety distance based on dynamic parameters, it is necessary to comprehensively consider the ship's braking needs in emergency situations and the physical effects generated during navigation. The basic safety distance must be determined based on the ship's ability to maintain safe avoidance and stable navigation. It must meet the distance requirements for routine navigation while also providing a buffer for emergencies. The results of this calculation serve as a baseline for subsequent revisions. Its core purpose is to establish a preliminary safety threshold under ideal conditions.

[0020] S3. Modify the basic safety distance according to the emergency scenario type in the navigation tunnel to generate the emergency scenario safety distance; Once the basic safety distance is calculated, it must be adjusted based on the types of emergency scenarios that may occur within the navigation tunnel. The type of emergency scenario depends on factors such as the tunnel structure, ship density, and environmental conditions. Examples include a sudden malfunction of a preceding ship or an obstacle within the tunnel. During the adjustment process, additional safety margins are added to the basic safety distance to address the specific needs of different emergency scenarios. The adjusted safety distance should cover the space required for evacuation and avoidance operations, ensuring that ships can maintain a safe distance in the event of an emergency.

[0021] S4. Adapt and adjust the emergency scenario safety distance according to the tunnel environmental parameters and output the final safety distance; Tunnel environmental parameters have a critical impact on the final formation of safe spacing. Factors such as tunnel width, longitudinal structural characteristics, and environmental visibility directly limit a vessel's maneuvering space and operational response time. During the adaptation and adjustment phase, the corrected safe spacing for emergency scenarios must be matched to the tunnel environmental parameters, and dynamic optimization is used to eliminate interference caused by environmental constraints. For example, in narrow tunnel sections, the spacing must be compressed or expanded based on the actual navigable space to ensure safe passage of ships within the confined space.

[0022] S5. Outputting navigation spacing control instructions for ships in the navigation tunnel based on the final safety spacing.

[0023] The resulting safe distance is converted into navigation control instructions, guiding the vessel to adjust its speed or position. The generation of these control instructions must take into account their real-time and enforceability, ensuring the vessel's rapid response. Through the synergistic effect of dynamic parameters, emergency scenario correction, and environmental adaptation, the safe distance analysis system achieves continuous optimization in complex and changing tunnel environments, mitigating safety risks caused by sudden environmental changes while maintaining stable navigation efficiency.

[0024] In practical applications, this method can effectively handle various scenarios within tunnels, including ship following, sudden braking, and obstacle avoidance. For example, when a leading vessel makes an emergency stop due to a malfunction, the system rapidly calculates a baseline safe distance using dynamic parameters, incorporates emergency scenario corrections, and adds avoidance redundancy. It then adjusts the final distance based on tunnel width and visibility, generating deceleration or lane change instructions to guide the following vessel to maintain a safe distance. This process fully demonstrates the advantages of layered dynamic adaptation, achieving a balance between safety and efficiency in different scenarios.

[0025] In some embodiments, Tunnel environmental parameters include tunnel section coefficient, tunnel width, total tunnel length, real-time water depth, visibility and discharge flow; Dynamic parameters include ship speed, ship width, ship braking performance, ship wave propagation distance and ship sinking amount; Ship braking performance includes braking reaction time and braking acceleration; The propagation distance of ship waves is calculated based on the ship speed, real-time water depth and tunnel section coefficient.

[0026] Analyzing safe spacing between ships in navigable tunnels requires identifying key parameters related to the tunnel environment and ship dynamics. Tunnel environmental parameters include tunnel cross-sectional coefficient, tunnel width, total tunnel length, real-time water depth, visibility, and discharge flow. The tunnel cross-sectional coefficient is a quantitative indicator describing the geometry of the tunnel's cross section and is used to assess the strength of constraints on navigable space; tunnel width directly determines the feasibility of lateral maneuvering by ships; total tunnel length influences the cumulative risk of ships sailing long distances; real-time water depth is the actual water depth in the tunnel dynamically monitored by sensors, reflecting the hydrological state of current navigation conditions; visibility parameters describe the degree to which light or fog in the tunnel interferes with the crew's visual judgment; and discharge flow represents the intensity of disturbances to the water velocity in the tunnel caused by the operation of hydraulic facilities. These parameters must be collected collaboratively through the tunnel monitoring system and ship terminal equipment to ensure the integrity and timeliness of the data source.

[0027] Ship dynamic parameters include ship speed, ship width, ship braking performance, ship wave propagation distance, and ship sinkage. Ship speed is the real-time navigation speed and directly affects the urgency of braking operations. Ship width is used to assess the lateral space occupied by the ship in the tunnel. Ship braking performance includes braking reaction time and braking acceleration, reflecting the ability of the ship's mechanical system to respond to receiving a command and completely stop. Ship wave propagation distance describes the range of influence of water waves generated by the ship during navigation on the ships in front and behind. Its calculation requires a combination of ship speed, real-time water depth, and tunnel cross-sectional coefficient. Ship sinkage is the real-time fluctuation of the ship's draft caused by changes in load or water flow. It is used to predict the risk of contact between the ship's bottom and the riverbed or obstacles.

[0028] The correlation between the tunnel cross-section coefficient and the ship-wave propagation distance can quantify the attenuation characteristics of wave interference between ships. During parameter collection, static parameters such as tunnel width and total length can be preset using design drawings and as-built data. Dynamic parameters such as real-time water depth, discharge flow, and ship speed require real-time sensor feedback. This combined dynamic and static parameter system not only provides the fundamental physical constraints for safe distance calculations, but also reserves a data interface for dynamic adaptation to sudden environmental changes.

[0029] The design of correlations between parameters must meet the requirements of multi-dimensional coupling analysis. For example, the calculation of the ship's wave propagation distance requires the simultaneous use of the ship's speed, real-time water depth, and tunnel cross-sectional coefficient, which together determine the attenuation rate of wave propagation. The coupled analysis of visibility parameters and braking reaction time can predict the additional safety distance requirements caused by crew operation delays in low-visibility environments. In actual applications, when visibility decreases, the system automatically increases the calculation weight of braking reaction time and adjusts the calculation logic of the ship's wave propagation distance based on the real-time water depth to ensure the dynamic adjustment capability of the safety distance.

[0030] Through the refined definition of the parameter system, the system can distinguish between the dynamic and static properties of different parameters. The tunnel cross-section coefficient, as a static geometric parameter, combined with the dynamic ship speed, jointly influences the propagation range of ship waves. This parameter classification mechanism ensures that safety clearance analysis can maintain stability based on design specifications while also enabling dynamic optimization in response to real-time environmental changes, providing underlying support for navigation safety in complex tunnel scenarios.

[0031] In some embodiments, the basic safety distance includes a weighted combination of the braking distance, the ship wave propagation distance, and the ship sinking amount; The calculation formula for braking distance is: ; Among them, D b is the braking distance, V is the ship speed, t r is the braking reaction time, is the braking acceleration; The calculation formula for the propagation distance of ship waves is: ; Among them, L w is the propagation distance of ship waves, k is the tunnel section coefficient, V is the ship speed, and h is the real-time water depth.

[0032] The calculation of the basic safety distance requires a comprehensive consideration of the physical influences of ship braking, ship wave propagation, and hull sinking. The calculation of the braking distance is based on the interaction of the ship's speed, braking reaction time, and braking acceleration. Its physical meaning is the gliding distance required for the ship to stop completely from the start of braking. The calculation formula for the braking distance is as above, where the ship's speed reflects the real-time sailing speed, the braking reaction time is the sum of the crew's operating delay and the mechanical response time, and the braking acceleration is determined by the performance of the ship's power system. The first term in the formula is the inertial gliding distance of the ship during the reaction time, and the second term is the theoretical displacement from braking deceleration to a standstill. The two together constitute the space requirement for emergency braking.

[0033] The calculation of the propagation distance of ship waves must take into account the range of interference that the waves generated by a ship during navigation have on the following ships. The energy propagation of ship waves is directly related to the ship's speed, water depth, and tunnel geometry, and the calculation formula is as shown above. Among them, the tunnel section coefficient is determined by the shape of the tunnel cross section, and the ship's speed and real-time water depth reflect the ship's motion state and hydrological conditions, respectively. The formula shows that the higher the speed and the shallower the water depth, the longer the ship wave propagation distance; and the tunnel section coefficient indirectly affects the propagation range by restricting the lateral diffusion of wave energy. For example, in a rectangular cross-section tunnel, the tunnel section coefficient is large, and the reflection of ship waves along the side walls will extend the propagation distance; while in a circular cross-section tunnel, the tunnel section coefficient is small, and the wave energy is more likely to attenuate to the surrounding areas.

[0034] The amount of a ship's sinking reflects the real-time changes in its draft due to changes in load or fluctuations in water buoyancy. This value is dynamically monitored by onboard sensors and analyzed in conjunction with real-time water depth data to predict the risk of the ship's bottom contacting the riverbed or obstacles. For example, if the ship's sinking exceeds the difference between the real-time water depth and the designed draft, the system will trigger a bottoming warning.

[0035] The final value of the basic safety distance is generated by a weighted combination of the braking distance, the ship wave propagation distance, and the ship sinking amount. The calculation formula is as follows: ; Among them, α is the safety redundancy coefficient, which is preset based on industry safety specifications.

[0036] In practice, the calculation of the basic safety distance must be synchronized in real time with the ship's dynamic parameters. For example, if the ship's speed suddenly increases due to current acceleration, the system automatically updates the calculation results of the braking distance and the ship's wave propagation distance. At the same time, the weighted combination coefficient is adjusted based on the fluctuation of the sinking amount to ensure the dynamic adaptation of the basic safety distance. This calculation mechanism can effectively cover a variety of risk scenarios such as sudden changes in braking performance, increased wave interference, and abnormal hull buoyancy, providing a stable baseline value for subsequent emergency corrections and environmental adaptation.

[0037] In some embodiments, S3 specifically includes: According to the emergency scenario type in the navigation tunnel, the emergency evacuation distance is superimposed on the basic safety distance to generate the emergency scenario safety distance; The calculation formula for emergency evacuation distance is: ; Among them, D e is the emergency evacuation distance, V vis is visibility, t escape is the preset personnel evacuation time, and t0 is the reference time constant.

[0038] The calculation of the emergency scenario safety distance requires superimposing the evacuation redundancy distance that matches the emergency type on the basic safety distance. The calculation of the emergency evacuation distance depends on the tunnel visibility parameters and the preset personnel evacuation time, as expressed in the formula above. Among them, visibility reflects the availability of visual conditions in the tunnel and directly affects the crew's recognition distance of emergency signals; the preset evacuation time is pre-set according to the type of emergency scenario, and the reference time constant is the time required for personnel to evacuate a unit distance under standard visibility. It can be preset through experiments or industry standards (for example, t0=2s means that evacuation takes 2 seconds for every meter of visibility). The coefficient in the formula reflects the compromise design of safety redundancy, which not only avoids the loss of navigation efficiency due to over-conservatism, but also ensures the space margin for evacuation operations.

[0039] The emergency scenario safety distance is generated by directly superimposing the emergency evacuation distance and the basic safety distance: ; The basic safety distance already accounts for the physical constraints of braking, ship wave motion, and sinking, while the superimposed emergency evacuation distance provides additional buffering for scenarios such as evacuation routes and rescue channel occupancy. For example, in a fire emergency, smoke diffusion compresses effective visibility. In this case, the system automatically reduces visibility and sets a shorter preset evacuation time based on the fire severity. The resulting emergency evacuation distance adapts to the needs of rapid evacuation in smoky environments.

[0040] The mapping relationship between emergency scenario types and parameters needs to be defined in advance. The collision scenario focuses on the space requirements for avoidance operations. At this time, the preset personnel evacuation time is the shortest time required for the ship to make an emergency turn. The flooding scenario focuses on the change in the evacuation path caused by the tilt of the hull, and the weight coefficient of the emergency evacuation distance needs to be increased. The flexibility of parameter configuration allows the same basic safety distance to be dynamically expanded according to different emergency types. For example, in a power outage scenario with extremely low visibility, the system prioritizes ensuring lateral avoidance space. At this time, the visibility takes the minimum value measured by the sensor, and the preset personnel evacuation time is set based on the blind spot navigation experience value to ensure that the emergency evacuation distance covers the risk of blind operation.

[0041] In practice, the calculation of emergency safety distances must be linked to event triggering mechanisms. When the tunnel monitoring system detects a fire alarm, it automatically calls the preset evacuation time parameters for the fire scenario, obtains real-time visibility data, calculates visibility, and overlays this with the latest basic safety distance to generate emergency instructions. This process ensures that the vessel can quickly switch to emergency distance mode in the event of an emergency, maintaining the effectiveness of basic safety constraints while enhancing risk response capabilities through scenario-adaptive redundancy.

[0042] In some embodiments, S4 specifically includes: When the ratio of tunnel width to ship width is less than the preset threshold, the final safety distance correction formula is: ; in, is the final safety distance, To provide a safe distance for emergency scenarios, is the ship width, is the tunnel width.

[0043] When the ratio of tunnel width to ship width does not meet the safe passage threshold, the emergency safety distance must be dynamically adjusted to generate the final safe distance. Tunnel width reflects the actual available space in the navigation section, while ship width determines its lateral space requirements. The ratio of the two directly affects the ship's avoidance ability and maneuverability in narrow areas. If the tunnel width is too small, the lateral clearance between ships during navigation may be compressed, leading to the risk of collision. In this case, the safety distance must be expanded to compensate based on the width ratio.

[0044] The final safety distance correction formula is shown above. This formula uses a safety margin threshold of 1.5 times the ship's width to determine whether the current tunnel width meets the ship's safe maneuvering requirements. If the actual tunnel width is less than 1.5 times the ship's width, the correction term becomes positive, requiring an increase in the safety distance. Conversely, if the tunnel width is sufficient, the correction term automatically returns to zero or is truncated to a negative value to avoid excessive redundancy.

[0045] In parameter design, the 1.5B threshold is set to account for the combined space requirements of ship lateral sway, wave disturbances, and operational errors. For example, in a narrow tunnel, if the ship width is 10 meters and the tunnel width is 12 meters (i.e., W=12, 1.5B=15), the correction factor is (15-12) / 10=0.3, resulting in a final safe distance of 1.3 times the emergency scenario safe distance. This design ensures that ships can offset lateral risks by increasing their distance within a limited space, while avoiding unnecessary increases in traffic density in wide tunnels.

[0046] In practice, the system monitors ship width and tunnel width data in real time and dynamically calculates the width ratio. When a ship is detected entering a narrow section (such as a tunnel entrance or curve), a correction formula is automatically triggered, proportionally expanding the emergency safety distance to the final safety distance. For example, when a cargo ship negotiates a narrow tunnel curve, the system adjusts the final safety distance in real time based on the difference between the ship's width and the measured tunnel width, guiding the following ship to maintain a clearance distance appropriate to the curve's curvature.

[0047] The underlying consideration behind the correction logic is to balance safety and efficiency. In narrow tunnels, the response time of ship steering and braking operations is prolonged, and the combined effect of wave reflection significantly increases the risk of side collisions. Through dynamic expansion driven by the width ratio, the final safe distance can not only suppress the risks brought by physical space constraints, but also avoid the loss of navigation efficiency caused by global distance amplification. For example, in a narrow tunnel with two-way navigation, the corrected final safe distance can simultaneously ensure the safety of passing oncoming ships without forcing unilateral navigation to stop.

[0048] In some embodiments, when applied to the through section of a dam lock, the final safety distance is superimposed with a water flow disturbance correction term, and the calculation formula of the water flow disturbance correction term is: ; Among them, D fl is the water disturbance correction term, β is the water disturbance coefficient, and Q is the discharge flow.

[0049] The navigational environment in the direct-access section of a dam lock is significantly impacted by water release operations. Therefore, a flow disturbance correction term must be added to the final safety clearance to offset the navigation risks posed by water instability. The discharge flow parameter is monitored in real time by dam gate sensors, reflecting the current water release intensity of the hydraulic structure. The flow disturbance coefficient, calibrated based on the lock's structural characteristics and historical navigation data, quantifies the degree of interference the discharge has on ship maneuverability. The product of these two factors constitutes the flow disturbance correction term, calculated as shown above. β is the flow disturbance coefficient, which quantifies the degree of interference the discharge has on ship maneuverability (dependent on the lock structure). It is derived from a pre-set lock structure database and dynamically adjusted by ship tonnage (e.g., rectangular locks have higher β and streamlined locks have lower β), and Q is the real-time discharge flow. This correction term directly relates to the dynamic relationship between discharge intensity and ship stability. For example, a large discharge can induce turbulence, leading to deviations in the ship's course or increased power compensation requirements, necessitating an extended safety clearance to provide a margin for interference.

[0050] When a ship enters the direct access section of the dam lock, the system automatically activates the water disturbance correction logic. The calculation results of the basic safety distance and the emergency scenario safety distance need to be further superimposed with the water disturbance correction term to generate the final safety distance adapted to the dam environment: ; in, It is the final safety distance after the correction of the superimposed water disturbance. For example, when the discharge flow suddenly increases, the system updates D according to the latest Q value. fl , and synchronously generate the updated , ensuring that the ship maintains its anti-drift capability in turbulent environments.

[0051] The calibration of the flow disturbance coefficient requires consideration of the lock structure and vessel type. For example, for a straight-through lock section with a rectangular cross-section, the lateral vortices generated by the release are stronger, so the β value should be higher; for a lock with a streamlined cross-section, β can be appropriately lowered. In practice, the system matches the β value based on a pre-set lock structure database and fine-tunes the correction coefficient based on the vessel's tonnage. For example, heavy cargo ships, due to their greater inertia, are relatively less affected by flow disturbances, so β ​​can be reduced; light passenger ships, on the other hand, require a higher β value to compensate for stability losses.

[0052] During the actual correction process, the monitoring frequency of the discharge flow and the refresh rate of the safety distance must be strictly synchronized. When the discharge gate opening changes, the flow sensor uploads the fluctuation data of Q in real time, and the system immediately calls the current β value of the ship lock to calculate D fl and superimposed with the final safety distance to generate This mechanism enables ships to dynamically respond to the periodic changes in discharge operations when passing through dam locks, such as automatically expanding the spacing during peak discharge periods and restoring the basic threshold during low discharge periods, thereby balancing safety and navigation efficiency.

[0053] In some embodiments, when applied to a long tunnel crossing a mountain range, the modified braking reaction time is: ; in, is the corrected braking reaction time, is the braking reaction time before correction, is the total length of the tunnel, For visibility.

[0054] The navigation environment in long tunnels across mountainous terrain is characterized by long longitudinal extensions and significant visibility degradation, necessitating dynamic adjustments to the braking reaction time to accommodate actual navigation risks. The correction formula for the braking reaction time is as follows.

[0055] The formula quantifies the impact of visual fatigue and signal recognition delays on operational efficiency during long-distance navigation by incorporating a ratio of tunnel length to visibility. For example, in a mountain tunnel exceeding 3 kilometers in length, if visibility is reduced to low values ​​due to fog, the correction factor in the formula will be significantly increased, extending braking reaction time to match the actual risk level.

[0056] Corrected brake reaction time Directly involved in the calculation of braking distance: ; The coupling effect of total tunnel length and visibility is Indirectly affects the value of braking distance. In long tunnels with low visibility, The extension of the braking distance will also increase the calculated braking distance, thereby expanding the baseline value of the basic safety distance. This dynamic correction mechanism enables the basic safety distance to cover the risk of visual fatigue accumulated during long-distance navigation and avoid insufficient safety margins due to operational delays.

[0057] In actual application, when the ship enters the mountain crossing section, the system monitors the remaining tunnel length and visibility data in real time and updates it dynamically. For example, when a ship is sailing to 3 km in a 5 km tunnel, the remaining tunnel length is 2 km. At this time, if the visibility drops to 50 meters due to a ventilation system failure, the system automatically calculates The correction range is calculated and the braking distance and basic safety distance are updated synchronously.

[0058] The underlying impact of the correction logic permeates the entire safety distance calculation chain. The expansion of the basic safety distance is propagated to subsequent emergency scenario correction steps, resulting in a simultaneous increase in the baseline value of the emergency scenario safety distance. During the final environmental adaptation of the safety distance, tunnel width and water flow disturbance corrections are added to the expanded baseline value. This progressive correction ensures that the safety distance in long tunnel scenarios consistently covers global risks, from braking operations to sudden environmental changes, creating end-to-end safety redundancy.

[0059] In some embodiments, when applied to a mixed-vessel scenario, the safety redundancy coefficients of cargo ships and passenger ships are set differently as follows: ; ; ; Among them, α cargo is the safety redundancy factor of the cargo ship, α passenger is the safety redundancy coefficient of the passenger ship, γ is the difference coefficient, which is used to characterize the safety redundancy reduction ratio of the cargo ship relative to the passenger ship. It is derived from the cargo type classification database (pre-set) combined with the navigation management rules (such as the dangerous goods γ is set by the Maritime Safety Administration), D safe,cargo is the basic safety distance of cargo ships, D safe,passenger is the basic safety distance of the passenger ship, and S is the sinking amount of the ship.

[0060] In mixed-use ship scenarios, safety redundancy factors need to be set differently based on the ship type to accommodate the different safety requirements of cargo ships and passenger ships. cargo ) and the safety redundancy factor of passenger ships (α passenger ) are related by the coefficient of variation (γ), as expressed above.

[0061] Here, γ is a coefficient of difference less than 1, reflecting the reduced safety margin for cargo ships relative to passenger ships. Passenger ships, due to their higher safety requirements, require a separate safety margin. For cargo ships, the safety margin is proportionally reduced based on the passenger ship factor to avoid wasting navigation resources due to excessive margin.

[0062] The basic safety distances of cargo ships and passenger ships are calculated by the above formulas. The differentiated safety redundancy coefficient is calculated by α cargo With α passenger A compensation item that acts on the amount of sinking of a ship. For example, a passenger ship needs to reserve a larger safety margin for sinking due to the number of passengers, while a cargo ship can appropriately reduce this margin.

[0063] Parameter calibration must be tailored to the vessel type and operational specifications. For passenger ships, the safety margin factor is typically set based on safety standards such as passenger capacity and life-saving equipment configuration. For cargo ships, the margin factor is adjusted based on cargo type (e.g., hazardous materials vs. general cargo). For example, a hazardous materials ship might have a γ value close to 1 to maintain a high margin, while a general cargo ship might use a lower γ value to improve navigation efficiency.

[0064] In actual application, the system obtains the ship type through the ship automatic identification system (AIS) and automatically matches the corresponding safety redundancy factor. When cargo ships and passenger ships pass through the tunnel together, the system generates differentiated basic safety distance instructions for them. For example, a passenger ship with 200 passengers sails parallel to an ordinary cargo ship. The α of the passenger ship is passenger Set to 1.2, the cargo ship's γ is set to 0.8, then the cargo ship's α cargo =1.2×0.8=0.96. Finally, the sinking compensation item in the safety distance calculation for cargo ships is S×0.96, while that for passenger ships is S×1.2.

[0065] The underlying consideration behind this differentiation strategy lies in balancing risk and efficiency. Extending safety redundancy for passenger ships can accommodate the space requirements for complex operations like passenger evacuation and emergency docking, while reducing the coefficient for cargo ships avoids channel congestion caused by redundant operations. For example, during peak hours in mixed traffic scenarios, a differentiated spacing strategy can ensure high safety for passenger ships while maintaining efficient cargo ship navigation, optimizing overall traffic flow.

[0066] In some implementations, further optimization may be performed for specific scenarios, specifically: When the system detects a fire alarm signal, it triggers the fire scene correction logic. Hull high temperature expansion compensation distance (D fire ) through the expansion coefficient (λ steel ) and temperature rise (ΔT) calculation: ; Where B is the ship width, λ steel is the thermal expansion coefficient of steel (preset), and ΔT is fed back in real time by the hull temperature sensor. The corrected emergency evacuation distance is: ; In the collision scenario, the anti-collision redundancy distance (D collision ) is determined by the hull structure strength grade (ρ struct )Decide: ; Among them, ρ struct Preset according to the ship anti-collision design specification. The revised emergency scenario safety distance is: ; In the flooding scenario, the system adjusts the evacuation path length according to the ship's tilt angle (θ): .

[0067] In some embodiments, the situation of multiple ships sailing can also be considered, and the enhancement effect of the number of parallel ships (n) on wave propagation can be superimposed. Specifically: When multiple ships are in parallel, the propagation distance of the ship wave (L w ) is corrected to: ; Where n is the number of ships in parallel, which is counted in real time by the tunnel monitoring system. For example, when two ships are in parallel, , suppressing the risk of insufficient spacing caused by wave superposition. The revised basic safety distance is updated to: .

[0068] In some embodiments, the impact of extreme weather conditions may also be considered. For example, in typhoon or rainstorm scenarios, visibility attenuation, water velocity, and wind and wave safety distance may be jointly corrected. Specifically: In typhoon scenarios, visibility parameters (V vis ) and wind speed (W wind ) Linkage attenuation: ; The discharge flow (Q) plus the wind driven water flow increment (ΔQ wind ): ; Where Across is the cross-sectional area of ​​the tunnel (preset). storm ) is based on the ship's windward area (A wind )calculate: ; The final safety distance correction is: .

[0069] Figure 2 A schematic diagram of a safe distance analysis system for ships sailing in a navigation tunnel provided by an embodiment of the present invention includes: An acquisition module 201 is used to acquire dynamic parameters of a ship in a navigation tunnel; A calculation module 202 is used to calculate the basic safety distance according to the dynamic parameters; A correction module 203 is used to correct the basic safety distance according to the emergency scenario type in the navigation tunnel to generate an emergency scenario safety distance; Adaptation module 204, used to adapt and adjust the emergency scenario safety distance according to tunnel environmental parameters and output the final safety distance; The output module 205 is used to output a navigation spacing control instruction for ships in the navigation tunnel based on the final safety spacing.

[0070] The system provided by the embodiment of the present invention has the same technical features as the above method, and therefore can achieve the same technical effects, which will not be described in detail here.

[0071] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the technical solutions of the embodiments of the present invention.

Claims

1. A method for analyzing safe distances for ships in navigation tunnels, characterized in that: include: S1. Obtain dynamic parameters of ships in a navigation tunnel; S2. Calculate the basic safety distance according to the dynamic parameters; S3. Modify the basic safety distance according to the type of emergency scenario in the navigation tunnel to generate an emergency scenario safety distance; S4. Adapt and adjust the emergency scenario safety distance according to the tunnel environmental parameters and output a final safety distance; S5. Outputting navigation spacing control instructions for ships in the navigation tunnel based on the final safety spacing.

2. The method for analyzing safe distances for ships sailing in a navigation tunnel according to claim 1, characterized in that: The tunnel environmental parameters include tunnel section coefficient, tunnel width, total tunnel length, real-time water depth, visibility and discharge flow; The dynamic parameters include ship speed, ship width, ship braking performance, ship wave propagation distance and ship sinking amount; The ship braking performance includes braking reaction time and braking acceleration; The ship wave propagation distance is calculated based on the ship speed, the real-time water depth and the tunnel section coefficient.

3. The method for analyzing safe distances for ships sailing in a navigation tunnel according to claim 2, characterized in that: The basic safety distance includes a weighted combination of the braking distance, the ship wave propagation distance and the ship sinking amount; The calculation formula of the braking distance is: ； Among them, D b is the braking distance, V is the ship speed, t r is the braking reaction time, is the braking acceleration; The calculation formula for the ship wave propagation distance is: ； Among them, L w is the propagation distance of the ship wave, k is the tunnel section coefficient, V is the ship speed, and h is the real-time water depth.

4. The method for analyzing safe distances for ships sailing in a navigation tunnel according to claim 2, characterized in that: The S3 specifically includes: According to the type of emergency scenario in the navigation tunnel, the emergency evacuation distance is superimposed on the basic safety distance to generate the emergency scenario safety distance; The calculation formula for the emergency evacuation distance is: ； Among them, D e is the emergency evacuation distance, V vis is the visibility, t escape is the preset personnel evacuation time, and t0 is the reference time constant.

5. The method for analyzing safe distances for ships sailing in a navigation tunnel according to claim 2, characterized in that: The S4 specifically includes: When the ratio of the tunnel width to the ship width is less than a preset threshold, the correction formula for the final safety distance is: ； in, is the final safety distance, The safety distance for the emergency scenario is is the width of the ship, is the tunnel width.

6. The method for analyzing safe distances for ships sailing in a navigation tunnel according to claim 2, characterized in that: When applied to the through section of a dam and ship lock, the final safety distance is superimposed with a water flow disturbance correction term. The calculation formula of the water flow disturbance correction term is: ； Among them, D fl is the water disturbance correction term, β is the water disturbance coefficient, and Q is the discharge flow.

7. The method for analyzing safe distances for ships sailing in a navigation tunnel according to claim 2, characterized in that: When applied to a long tunnel crossing a mountain range, the revised braking reaction time is: ； in, is the corrected braking reaction time, is the braking reaction time before correction, is the total length of the tunnel, For the visibility.

8. The dynamic analysis method for safe navigation distance of ships in a navigation tunnel according to claim 3 is characterized in that: When applied to mixed-vessel scenarios, the formula for setting the safety redundancy coefficients for cargo ships and passenger ships is as follows: ； ； ； Among them, α cargo is the safety redundancy factor of the cargo ship, α passenger is the safety redundancy coefficient of the passenger ship, γ is the difference coefficient, D safe,cargo is the basic safety distance of cargo ships, D safe,passenger is the basic safety distance of the passenger ship, and S is the sinking amount of the ship.

9. A safety distance analysis system for ships sailing in a navigation tunnel, characterized in that: include: An acquisition module is used to obtain dynamic parameters of ships in the navigation tunnel; A calculation module, configured to calculate a basic safety distance according to the dynamic parameters; A correction module, configured to correct the basic safety distance according to the type of emergency scenario in the navigation tunnel to generate an emergency scenario safety distance; An adaptation module, configured to adapt and adjust the emergency scenario safety distance according to tunnel environmental parameters and output a final safety distance; An output module is used to output a navigation spacing control instruction for ships in the navigation tunnel based on the final safety spacing.

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