Details:
Customer
Novenco Marine & Offshore A/S
Technology Used
- Ansys Fluent
- Ansys SpaceClaim
Objective:
Evaluate and optimize the airflow and temperature field inside a ship's generator and engine rooms using CFD simulation.
Challenge:
Novenco Marine & Offshore's main concern was the excessive heat buildup observed in the main engine and generator rooms - especially on the lowest decks - caused by insufficient cooling airflow. To reduce the temperature, Novenco Marine & Offshore redirected ventilation ducts from the 3rd and 4th decks downwards to deliver more cooling air to the lower levels. Simtec used CFD simulation to verify the effectiveness of this revised ducting layout.
Accurate modeling of the thermal environment in enclosed spaces requires realistic modeling of heat transfer through conduction, convection, and radiation, as well as the distribution of turbulent and buoyant airflow across multiple ventilation branches. The task was further complicated by the lack of 3D CAD data, which made it necessary to reconstruct the multi-deck geometry using available 3D scans and 2D drawings.
Solution:
Simtec rebuilt the air volume geometry of the rooms under investigation, along with adjacent spaces in Ansys SpaceClaim using 3D scans and 2D drawings to produce simplified representations of key components. A high-quality poly-hexcore mesh was generated to resolve the geometric model composed of a large number of spaces, whereas near-wall flow effects were treated by four mesh inflation layers attached to all walls. The CFD model accounted for buoyant flow, employed temperature-dependent air properties, detailed heat transfer models, and realistic thermal boundary conditions. Air supply flow rates and temperatures were defined based on operating data.
Conclusion:
The results of Novenco Marine & Offshore’s proposed solution showed that the engine rooms maintained acceptable temperatures, while the generator rooms exhibited higher values.
CFD simulations confirmed that the redesigned ducting, performed by Novenco Marine & Offshore, reduced average temperatures by at least 10 °C in all rooms, bringing a significant improvement compared to the previous ducting layout. This CFD project assessed how increasing cooling supply airflow can lower the temperature in enclosed environments with significant heat dissipation from machinery. The insights provided by Simtec simulations support and guide Novenco Marine & Offshore’s efforts to enhance HVAC system performance in demanding marine environments.
CFD simulations confirmed that the redesigned ducting, performed by Novenco Marine & Offshore, reduced average temperatures by at least 10 °C in all rooms, bringing a significant improvement compared to the previous ducting layout. This CFD project assessed how increasing cooling supply airflow can lower the temperature in enclosed environments with significant heat dissipation from machinery. The insights provided by Simtec simulations support and guide Novenco Marine & Offshore’s efforts to enhance HVAC system performance in demanding marine environments.
Figure 1: Geometry of the Stern Side of the Vessel: (a) Original 3D Scanned Surfaces and (b) Constructed CFD Model.
Figure 2: Temperature Field at Vessel Internal and External Walls for the Proposed Solution by Novenco Marine & Offshore.
Figure 3: Temperature Field at a Horizontal Plane through the Engine and Genset Rooms for the Proposed Solution by Novenco Marine & Offshore.
Figure 4: Temperature Field at Two Vertical Planes through the Engine and Genset Rooms for the Proposed Solution by Novenco Marine & Offshore.
Figure 5: Pathlines Colored with Air Temperature are Released from Selected Supply Diffusers to Provide Valuable Insight on the Spatial Effect of Specific HVAC Components.
