TURBONAV Project - Development and implementation of modern solutions related to gas turbine propulsion systems and related systems
Project presentation

The main purpose of TURBONAV is the developing and testing in stand conditions of a turbo engine technological demonstrator with shaft power for operation in the marine environment.    
The project aims to identify and implement a solution to modernize gas turbine propulsion systems used in the naval field by adapting existing systems to cutting-edge technologies and developing emerging technologies for systems related to propulsion systems, with application in the marine environment.   
 The results of the research carried out within the project will allow exceeding the current stage of the performances achieved by the currently existing motors, allowing the achievement of a more than 15% higher thermal efficiency and a lower specific fuel consumption, which results in reduced pollution and also in a reduction of operating costs. Following some research and studies of some industrial turbo engines, a constructive architecture of a marine propulsion solution was built by developing a turbo engine with a shaft power of 5000 kW specially designed for work in the marine environment that will be equipped with mechanical components and command and control systems in order to optimally correspond to all the technical and operational requirements specific to the propulsion of military and civil ships.
Determining the configuration, designing, implementing and testing the optimal solution was done based on the experience and expertise of the technical and scientific teams of the consortium, and using techniques and technologies of high performance and reliability. Thus, numerical CFD simulations of the flow through the air intake and combustion gas exhaust ducts, newly designed, were performed, as well as heat transfer and material resistance calculations. The mechanical design of components and SDVs used CAD computer-aided design systems.
The experimental tests aimed at determining the overall performance of the engine in the new configuration, as well as gathering relevant experimental data for optimization.
Considering the training and experience of the implementation team as well as the existing infrastructure, we consider that the project purposes are achievable.

Project results
Stage 1. Final arhitecture configuration

During this stage activities were carried out to reveal the ship's cruise cell, as well as research and studies to define and establish the architecture of the propulsion solution for the ship with the ST40M engine, and design and configuration activities for the installation of the ST40M engine in the stand.
Research/studies were also carried out to define/establish the system architecture by defining the position and fixing of the ST40M engine in the ship's cruise cell, defining the power transmission coupling from the engine to the ship's propeller as well as defining the engine air intake ducts, and combustion gas exhaust, establishing the requirements for the fuel, lubrication, air and ventilation systems, the 3D model of the turbo engine in the cruise cell (modelul 3D al turbomotorului în celula de marş), based on the results of the dimensional surveys of the ship's cruise cell.

After establishing the mechanical configuration (fig.1), the command and control scheme of the ST40M engine in the stand and on the ship was established. The command and control system of the ST40M engine in the stand was configured in order to ensure starting, safe operation and stopping the engine but also integrating the ST40M engine into the ship's command and control system. Local and remote engine control is ensured. The parameters when starting the engine but also during operation are visualized and saved for analysis.
The command and control system for testing the ST40M engine in the stand has the role of starting, accelerating, decelerating and stopping the engine for the test samples in the test stand. It includes modules and sub-assemblies that allow monitoring of the engine parameters and provide the commands necessary to start, control the engine during operation and stop the engine. The sub-assemblies of the system must interact with the elements of the stand that ensure the operation of the engine within the provided parameters.

Fig. 1 ST40M engine installation configuration diagram in the COMOTI stand

After establishing the configuration in fig 1, the execution documentation (technical report and execution drawings) was created for the main mechanical components: the engine support and fixing assembly, the air intake and exhaust gas ducting and the connection coupling between the ST40M engine and the dynamometer from the COMOTI stand.
Based on the execution drawings, the flow calculation was made for the air ducting and gas exhaust of the ST40M engine in the stand.
The numerical analysis was performed using the commercial ANSYS CFX software. Following the CFD analysis, the necessary corrections were made to minimize the losses on the intake and exhaust routes.
The project of the command and control system was also created - the technical report, the drawings of the electrical equipment, the electrical diagrams and the specification of the devices included in the system. The dimensions of the components were made taking into account the location and the environment in which the system operates. The choice of the system configuration was made in such a way as to ensure the command and control of the turbo engine in the optimal operating parameters.

Stage 2. Research and development for the technological demonstrator on the stand

During this stage, activities were carried out to survey the ship's cruise cell in order to install the technological demonstrator with ST40M on the ship, and the execution documentation was created for the technological demonstrator equipped with the ST40M naval turbo engine for installation and testing in the COMOTI stand, the equipment and materials necessary for the implementation of the technological demonstrator were purchased, the components necessary for the technological demonstrator were launched in manufacturing, the final assembly of the technological demonstrator was assembled on the COMOTI stand.
The final configuration of the technological demonstrator with ST40M was made (fig.2)

Fig.2 Technological demonstrator installation general assembly equipped with ST40M engine in the COMOTI stand

Main components produced:
The developing of the command and control system includes all the electrical and automatic equipment mounted on the engine or near it, necessary for the command and control of the operation of the propulsion system. Parameters are displayed on a local panel and registered with the help of an acquisition system.
Testing the technological demonstrator with ST40M in the COMOTI stand.

As part of this activity, testing was carried out on the COMOTI test stand of the technological demonstrator group equipped with the ST40M engine, delivered by Pratt&Whitney. The testing of the demonstrator group was carried out with the engine installed and equipped in the configuration in which it will work on the ship, in order to evaluate the operating conditions and performances of the ST40M engine in real operating conditions.
Both the commissioning of the ST40M engine and the verification of its operation in the entire range of operation, under the conditions of using the power and lubrication installations, the control systems and the instrumentation designed for operation on the ship was carried out. The parameters of the demonstrator group were determined in its entire field of operation and the performances that it can provide by being installed in the ship's propulsion system were evaluated.
The testing of the technological demonstrator with the ST40M engine included the functioning tests of the demonstrator group in the stand, the experimental elevation of the group parameters, and the determination of the overall characteristics of the power group (fig. 8 and fig. 9).

Fig. 8 The variation of the power turbine speed - NTP - depending on the speed of the high pressure rotor - NH for technological demonstrator with ST40M

Fig. 9 Variation of the power turbine-W- according to the speed of the high-pressure rotor -NH for technological demonstrator with ST40M

Stage 3. Installation and testing of a technological demonstrator on board a T22R type frigate

During this stage, activities were carried out in order to install the technological demonstrator with ST40M on the ship, and the execution documentation was created for the adaptations to the technological demonstrator with ST40M installed and tested in the COMOTI stand for integration in the ship's cruise cell, the equipment and the necessary materials was purchased and the necessary components for the installation on the ship were manufactured, the final assembly of the technological demonstrator was mounted on the ship and the functional tests were carried out.

Fig.10 Schematic of the test configuration of the technological demonstrator with ST40M on the ship

The main designed components:

Fig.12 Adaptation of the gas exhaust duct of the technological demonstrator with ST40M to the ship's exhaust system

The command and control system of the propulsion group used for the experiments in the COMOTI stand was fully integrated into the ship's command and control system.

Fig. 16. Block diagram of the ST40M engine integration on the ship

Testing the technology demonstrator with the ST40M on the ship

The testing of the technological demonstrator with the ST40M engine on the ship included the following:
- Preliminary activities, to prepare the naval propulsion group for commissioning (house tests), which included checks and adjustments necessary to ensure the start-up conditions and normal hot operation of the turbo engine, the related installations and the automation system.
- Quay testing - the start-up and the idle running of the naval propulsion group at different regimes, the functional parameters of the installations, the verification of the tightness of the lubrication and fuel systems, the thermal regime of the fluids in the system, the drainage and the way the systems of control responds to commands, normal and emergency stop.
- On-the-move testing, which was carried out with the ship in motion, with the naval propulsion group adjusted to operate at regimes between idle and maximum running. The loading of the power turbine of the propulsion system was achieved by varying the propeller pitch and speed. The following tests provided in the experimentation program were carried out:
- the underway test of the naval propulsion group. The test was carried out with the two propulsion lines operating at the same regimes and maximum pitch of the propeller for symmetrical propulsion of the ship and to compare the parameters of the two lines:
- switching the ship's propulsion from the cruise engine to the booster engine and vice versa;
- checking the propulsion system, accelerations and decelerations;
- the endurance test.
- cruise forward with the propulsion group with ST40M in operation on the port side and towed shaft on the starboard side;
- forward and backward cruise halves;
- cruise forward with both lines at an optimal/silent pace.

It was considered that these tests, successfully carried out by the propulsion group with ST40M installed on the frigate, cover the entire range of tests necessary to demonstrate the functionality of the propulsion line equipped with the ST 40M engine, to confirm its performance and maneuverability.

Fig. 17 Variation of shaft power depending on the speed of the power turbine for the propulsion group with ST40M

Stage 4. Development of documentation and personnel training

During this stage, the project team developed the technical documentation necessary for the training of personnel of the Romanian Naval Forces, as well as the training course for the operation of the ST40M turbo engine naval propulsion group that will be installed on board a T22R type frigate.

Documentation development

Technical descriptions of the product and the command and control system as well as operating procedures of a ST40M turbo engine naval propulsion group equipped for installation on a T22R type ship were developed.

Development of technical description for the naval propulsion group with ST40M

The technical description for the product “Naval propulsion group with ST40M”, includes the diagram of the basic product (Fig.1) continuing with the detailed description of the general assembly of the product installed on the ship, mentioning the main components.
Installation/disassembly procedures were also developed for the air intake duct, the flue gas exhaust duct, and the product lubrication system.
Development of technical description of the command and control system for the naval propulsion group with ST40M

The technical description for the command and control system of the ST40M marine propulsion group includes the block diagram of the product command and control system (Fig. 2), continuing with the detailed description of the automation cabinet, junction boxes and wiring.

Documentation development

Technical descriptions of the product and the command and control system as well as operating procedures of a ST40M turbo engine naval propulsion group equipped for installation on a T22R type ship were developed.

Development of technical description for the naval propulsion group with ST40M

The technical description for the product “Naval propulsion group with ST40M”, includes the diagram of the basic product (Fig.1) continuing with the detailed description of the general assembly of the product installed on the ship, mentioning the main components.
Installation/disassembly procedures were also developed for the air intake duct, the flue gas exhaust duct, and the product lubrication system.

Fig.2 Diagram of the product command and control system

Development of operating procedures for the naval propulsion group with ST40M

The procedure presents the necessary information for the operation of the ST40M Naval Propulsion Group installed on the T22R frigate, under the conditions of control of the propulsion group with an automation system using a Programmable Controller (PLC).
During the procedure, all the operating functions of the Naval Propulsion Group are presented: COLD start, DECO start, HOT start, MODE operation and turbo engine shutdown.
The operating functions of the Naval Propulsion Group are shown on the display of the automation cabinet.

For further information click here.

COLD start

The cold start is performed to ventilate the turbo engine and the gas-dynamic path. The start is ordered by pressing the "START" key. The programmable controller (PLC) automatically runs the next cold spin sequence according to the algorithm implemented in the software. The cold start is stopped by pressing the "STOP" button or automatically, 45 seconds after pressing the "START" key.

DECO Start

Starting with deconservation takes place in the same way as cold starting with the difference that the fuel injection path is opened in the combustion chamber without connecting the spark plugs.
The programmable controller (PLC) automatically runs the spin sequence with deconservation according to the established algorithm. It is carried out identically to the cold rotation, with the difference that fuel is injected and it is allowed to operate for 15 ÷ 20 sec, after which it stops. The existence of fuel leaks through the combustion chamber drains is monitored.

WARM start

With the warm start, the turbo engine is put into operation by bringing it from the stopped state to the idle operating state. The start is ordered by pressing the "START" button and the programmable controller (PLC) automatically runs the warm start sequence. After the turbo engine idles, the values of the parameters that characterize the idle mode are checked (speeds, combustion gas temperature, oil pressure, vibrations, etc.) and compare with reference values. If the parameters have normal values, the turbo engine is left to stabilize thermally for at least 3 minutes.

Mode operation

After reaching the idle regime, the program enters the "Operation at regime" state. The operating mode of the turbo engine can be varied between idling and maximum mode by increasing or decreasing keys or manually operating the control lever. The speed and pitch of the ship's propeller varies according to the regulation law imposed by the automatic on the propulsion line.

Stopping the turbo engine

Stopping the turbo engine can be done automatically by command given by the Command and Control System when a protection limit is exceeded, or by manual command from the operator. Stopping the turbo engine can be ‘normal stop’ or ‘emergency stop’.

Personnel Training

In order to provide training, based on the completed documentation, a Training Material was created, which was used for the training of personnel of the Romanian Naval Forces in a training course organized at COMOTI headquarters.

The training plan included two directions:
• the theoretical part for a better learning of the training material;
• the practical part, with the students participation in multiple start-ups and operating exercises, carried out at the COMOTI stand with the ST40M technological demonstrator that was installed on the ship.
In September 2020, a training course was held with Romanian Naval Forces personnel. Stage 4 was the last stage of the project implementation plan. The project "Development and implementation of modern solutions related to gas turbine propulsion systems and their related systems", TURBONAV, was successfully completed, ending with the development of a naval propulsion group product, capable of re-engineering T22R frigate ships.