* Mircea cel Bătrân Naval Academy, Constanţa ** Histria Shipmanagement S.R.L., Constanţa ***S.C. DELATREID, Constanţa

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1 CONSIDERATIONS RELATING MAN K8SZ 70/150 CLe NAVAL DIESEL ENGINE OPERATION WITH HEAVY MARINE FUELS *Prof.Eng. Traian FLOREA, PhD *Prof.Eng. Alexandru DRAGALINA, PhD *Prof.Eng. Anastase PRUIU, PhD **Eng.Nicolae BERECHET, PhD ***Eng. Traian-Vasile FLOREA *Alexandru-Ion DRAGALINA * Mircea cel Bătrân Naval Academy, Constanţa ** Histria Shipmanagement S.R.L., Constanţa ***S.C. DELATREID, Constanţa Abstract This paper presents the results of a research which aimed at highlighting particularities operation with heavy residual fuel of a naval propulsion engine. Keywords Engine, diesel, naval, propulsion, operation 1. Preliminary considerations In order to reflect the changes within the naval engines operations with heavy fuel, in comparison to operations with the reference fuel (diesel), since 2005 there were carried out a series of measurements of functional parameters of naval propulsion engines. The first set of determinations has been made with the ship in normal operations, during and Purchases have been made on the Histria Diamond ship, which transports primary petroleum products (oil); it was built in Constanta shipyard in 1989 and equipped with the propulsion engine type MAN K8SZ 70/150 CLe. In Table no. 1, the main features of the ship are presented, while in table 2, the main features of the propulsion engine are included. Table no. 1 Constructive-functional features of the vessel "Diamond Histria" Name of the ship: Histria Diamond Ship speed: 12,5 knots Year of construction: 1989 Total length: 228,2 m Place of building: Constanta Shipyard Maximum width: 43 m Type of ship: Primary petroleum products transport Height of construction: 19 m Displacement: tdw Propulsion engine MAN K8SZ 70/150 CLe 51

2 Table no. 2 Constructive-functional features of MAN K8SZ 70/150 CLe engines Engine: MAN K8SZ 70/150 CLe Piston stroke: 1500 mm K with cross-head; Reversible engine 8 number of cylinders; (march before : Rotation direction: S easy to maintain; clockwisw, seen Z in 2 strokes; from flywheel) Symbol 70 bore, in cm; Compression report: 1/12 meanings: 150 piston stroke, in cm; Average effective 12,04 bar C construction noted; pressure: L low speed engine; Maximum e economic version. combustion pressure: 110 bar Engine builder: U.C.M. Resita, Romania Ignition order: Stroke number: 2 Turbocharger: N 48, type TC 776 Number of 8 in line Maximum work 500 C cylinders: Maximum Continuos Ra-ting (Engine Power): Nominal speed: Bore: kw (15230 ) 114 rpm 700 mm temperature: Turbocharging pressure: Specific fuel consumption: Lubrication oil consumption (cylinder liners): 2 bar 190 g/kwh, at MCR 1, ,90 g/kwh, at MCR 2. Operational parameters measured in the experimental researches In the experimental researches, the parameters in Table no. 3 were determined, in diverse operating conditions of naval diesel engine. Table no. 3 (I) Operational parameters measured during experimental researches Parameter M.U. Parameter M.U. Engine power (Engine output) [kw] Engine room temperature [ C] Cylinder power* [kw] Turbocharging air temperature [ C] Engine Load [%] Scavenge air temperature* [ C] Engine speed [rpm] Cooling fresh water temperature [ C] Turbocharger speed [rot/min] Sea water temperature [ C] 52

3 Table no. 3 (II) Operational parameters measured during experimental researches Parameter M.U. Parameter M.U. Fuel oil consumption [kg]; [kg/h]; Cylinder cooling water [kg/kwh] temperature (inlet/outlet)* [ C] Lube oil consumption [kg]; [kg/h]; Piston cooling water [kg/kwh] temperature (inlet/outlet)* [ C] Barometer pressure [mbar] Injector cooling water temperature (inlet/outlet)* [ C] Turbocharging air pressure [bar] Lube oil temperature [ C] Scavenge air pressure* [bar] Exhaust gas temperature* [ C] Compression pressure* [bar] Fuel temperature at injection [ C] Maximum combustion [bar] Engine room humidity [%] pressure* Mean effective/indicate pressure Pressure drop of turbocharging air in coolers [bar] [mmh 2 O] Fuel injection pump index* Weather & sea conditions Observation: the size marked with * is determined for each engine cylinder. [mm] Sea degree; Force&direction of wind 3. Experimental results In the experimental researches, the first set of measurements of operational parameters of the engine MAN K8SZ 70/ 150CLe was made with the existing equipment and devices on board Histria Diamond and a portable electronic device type EPM-XS, produced by the company AIMES Ltd. Determinations have endorsed the establishment of functional values of the parameters in terms of engine operation with heavy residual fuel. The results are presented in the form of measurements files, like those presented in Figures no. 1 and no. 2. Based on this data, the functional diagram of the engine in Figure no. 3 was made, and it illustrates the variations depending on the engine speed of the operational parameters, such as effective power, compression and combustion pressure, exhaust gas temperature before and after the turbocharger, turbocharging air pressure, opening of fuel injection pump (pump index), pressure drop in the air cooler, specific fuel consumption. Fig. no. 1 Measurements file made on , for the MAN K8SZ 70/150 CLe engine, during normal operation 53

4 Fig. no. 2 Measurements file made on , for the MAN K8SZ 70/150 CLe engine, during normal operation Fig. no. 3 Operational parameters diagram of the MAN K8SZ 70/150 CLe engine 54

5 4. Results processing and interpretation A first set of determinations has been made in terms of closed operational regimes of engine power and speed: 2 determination A ( ): P e = 9930 and n = 97 rpm; determination B ( ): P e = 9065 and n = 96 rpm; determination C ( ): P e = and n = 99 rpm; determination D ( ): P e = 9284 and n = 95 rpm. Based on this data, the distribution of cylinder powers recorded in the four determinations is presented in Figure no. 4. They calculated the average values and the percentage deviations of the registered parameters. The results are included in Table 4; in Figure 5 the distribution of these dispersions is presented. It may be noted that, in the last two determinations, decreased the uniformity of cylinders loadings. This has led to the need for execution of maintenance works, including adjusting the angles of advance injection and cleaning of exhaust gas spaces from recovery caldaria cyl.no.1 cyl.no.2 cyl.no.3 cyl.no.4 cyl.no.5 cyl.no.6 cyl.no.7 cyl.no.8 Determination A Determination B Determination C Deternination D Fig. no. 4 Spread of cylinder powers Percentage deviation of cylinder power P cil [%] Parameter Average value 1241,262 A 1134,625 B 1303,237 C 1160,437 D Table no. 4 Percentage deviations of operational parameters Cylinder No ,000 1,665 +1,018 +1,945 3,002 0,956 +1,115 0,891 0,478 +1,540 +0,412 +1,196 1,377 0,646 2,100 +1,928 +6,765 1,729 2,819 0,762 3,686 1,783 +3,573 +0,442 +4,650 +0,161 +0,393 +1,858 4,364 3,648 +1,083 0,132 55

6 cyl.no.1 cyl.no.4 cyl.no.3 cyl.no.2 cyl.no.5 cyl.no.6 cyl.no.7 cyl.no.8 Determination A Determination C Determination B Determination D Fig. no. 5 Spread of percentage deviations of cylinder powers. Bibliography 1. Berechet, Nicolae, Contribuţii la studiul parametrilor funcţionali ai motoarelor navale la funcţionarea pe combustibil marin greu, PhD Thesis, Bucharest, Military Technical Academy, Dragalina, Alexandru, Motoare cu ardere internă, Constanţa, Mircea cel Bătrân Naval Academy Publishing House, Pruiu, Anastase, Instalaţii energetice navale, Constanţa, Muntenia & Leda Publishing House, Pruiu, Anastase, Berechet, Nicolae, Studiul posibilităţilor de utilizare a combustibilului rezidual sau a amestecurilor de combustibili la motoarele navale principale şi auxiliare, The 14 th National Thermo-Technical Conference, Bucharest,