Metri Pro-Lite and the Hybrid Passenger Ferry

iCenta were called to consult on a number of flow applications on board a multi-million-pound new generation of catamaran hybrid passenger ferry. They will operate on the Thames, and there will be a new ULEZ style charge for River vessels, where Tower bridge will become the region for charges to apply. Far Eastern Ultrasonic flowmeters were installed, and shipyard needed help analysing the data.

An early start was required as the ferry was built on the Isle of Wight. After finding ourselves in East Cowes, we nipped on another boat to get over to West Cowes and started our work.

The application was for diesel fuel consumption on as common rail engine (so flow and return) and cooling water for both the batteries and the diesel engines. There was a diesel/electric power plant in each of the 2 hulls, so that was 4 measurement point per hull, so 8 in total. The battery cooing fluid was a drinking water / glycol mix and flowed around a heat exchanger, whilst the diesel engine cooling was raw sea water, drawn up and passed through a strainer. The pipe was Nickel Copper alloy, DN25 (fuel lines) DN50 and DN100 line sizes for the two cooling circuits.

In terms of the diesel flow, a gear flow meter was installed, but Paul Gentle noticed that it was sized incorrectly and one of the correct sizes would be required. A precision OVAL FlowPet 5G gear meter from Japan was selected for the task of flow measurement from the diesel common rail engine.

Next the cooling circuits were surveyed, and the existing ultrasonic sensors were installed not below deck, but below the lower deck – within the bilge. Access was extremely tight; the space was about 60 cm at its largest point and a person could not turn around down there. After a safety gas monitor check, iCenta staff disappeared into the bowels of the boat armed with the ultrasonic meters which were set-up and the sensors installed. It is in such applications where a quick setup and small meter is a definite advantage.

Precision Flow DP 190 on raw sea water intake.

Limited access on DN50 cooling pipe, using Metri Pro-Lite with Precision Flow rail!

Precision Flow sensors (Metri rail)!

Both the Metri Pro-Lite and the Precision Flow PD190 measured the flow well, but it was found that as the engine approached full power, a great deal of entrained air did become mixed into the engine cooling pipe, which is bad for ultrasonics, and many technologies and of course air will not make an efficient heat transfer medium. The ultrasonic flowmeters showed themselves (due to entrained air) that on the diesel engine cooling circuit, a different flow technology was required. This remains a natural strength of iCenta, we have all the flowmeter technologies, so we can honestly recommend the best flowmeter technology choice and we get a chance to represent the very best instrument from around the World. Initially we thought that it was a good application for ultrasonics, but as the environment was hot and access was very limited, it was felt that really a more traditional invasive flow meter was a better choice. The ultrasonics did however give us insight into the flow conditions. In fact, a combined Doppler – Transit time flow meter is available Precision Flow from iCenta, and this would have been a good application. The new Metri Pro-Lite was easy to use and it a great spot-checking tool for many industries.

The Metri Pro-Lite has built in graphical diagnostics – a useful feature when monitoring on unusual fluids.

After the trial, the new meters were correctly specified and sized, so the overall solution involved Oval geared meters and C-Mag Comac Cal 316L Magnetic flowmeters.

Saying farewell to the Red Funnel passenger ferry after a great day of flow measurement testing.