DEPAS - Diesel Engine Performance Analysing Systems

Depas 2.34sp ScreenShot DEPAS 2.34sp

These systems are used on ship, railway and stationary diesel installations since 1996. Rich experience of operation allowed to create highly effective Phaseless Synchronisation (PLS) algorithm - definition of TDC, BDC and subsequent synchronization of data without usage of any sensors on a flywheel.

Parameters of working process are determined on three information channels: fuel combustion, fuel injection, valves timing.

The basic measuring element of system is the gas pressure sensor PS-16 (uncooled type). From it the necessary data is obtained for calculation of indicated cylinder power and definition of the basic characteristics of working process.

Vibrosensor VS-20 is the auxiliary sensor of the system. The vibroanalysis of the various units of the fuel equipment and cylinder moving parts of a diesel engine allows to determine parameters of fuel- and valves timing.

Distinctive feature of DEPAS systems is usage of special algorithm for definition of the piston TDC - PLS algorithm. The algorithm has been developed and applied for the first time in DEPAS systems in 1996. From now on PLS algorithm has passed long testing for different types of engines and has been improved on the basis of the analysis of a huge amount of a accumulated experimental data.

The operational experience accumulated by us in the field of diesel engines monitoring allows to approve the following: usage of PLS algorithm at practical diesel engines indicating is more preferable on the following reasons:

A: TDC determination error account
***Fitting of phase sensor and flywheel marker (for TDC determination) is performed on non-working engine. During engine running correct TDC position is shifting due to crankshaft twisting (proportional to engine load); torsional vibration; engine moving parts clearances and other factors which is impossible to calculate in static conditions***
- PLS algorithm automatically accounting influence of crankshaft twisting under load (see example from 10K45GF B&W engine);
- PLS algorithm automatically accounting influence of discrepancy between true position of TDC and flywheel mark, due to influence of the excessive clearances in the engine moving parts and other operational factors(also possible non-accurate flywheel marking of the engine maker);
- PLS algorithm automatically accounting influence of pressure waves passage speed through the indicator cock channel (from the combustion chamber to the pressure sensor diaphragm);
B: possibility to perform indicating without additional engine preparation
***During working with engine performance systems which are using flywheel sensor and mark one of the most time and job consuming operation is fitting and adjusting of a flywheel sensor and flywheel marker***
- there are no wasted time and cost for installation of synchronizing sensors on flywheel;
- application of PLS algorithm allows to make a diesel engine indicating without special preparation which is necessary at hardware data synchronization (with flywheel sensors).

Accuracy of PLS algorithm and its correctness for different types of engines have been proved experimentally by comparison of real and calculated TDC data.

Now system DEPAS 2.34sp is developed in portable variant.

DEPAS systems allow to supervise a technical condition of the fuel equipment and engines moving parts according to requirements of the Appendix VI of MARPOL 73/78.

Use of systems DEPAS is approved by the Russian River Register.

The DEPAS 2... software, including all used mathematical algorithms of real time data processing and hardware (exhaust gas pressure sensors PS-16, PS-16m; vibrosensor VS-20, and also additional fuel high pressure sensor PS-150 and a high pressure fuel valve V-200) are developed in the DEPAS Laboratory.


Handy 1.0 Screenshots Depas 4.0 Handy

In 2011 the new portable system of diesel engines working process monitoring DEPAS 4.0H is developed. Said system is an improved version of DEPAS 2.34sp and belongs to "divided monitoring" systems.

DEPAS 4.0H is created on the basis of the modern high-efficiency controller with a high degree of integration.

The basic feature of system DEPAS 4.0H is that the real time data module is separated from the calculation module (“ the divided monitoring “) and is executed on the basis of the specialized controller. Communication between modules is carried out on the serial interface. The system allows to monitor working process of 2- and 4-strokes slow-, middle- and high speed engines (in all ranges of rpm with the accuracy not less than 0.5o). In non-volatile FLASH memory of the controller it can be kept up to 100 sessions of indicating. Duration of independent work from batteries – 7 hours.

Monitoring of diesel engine working process is carried out on following key parameters: average indicated pressure and indicated power; average, minimal and maximal pressure of fuel combustion in the cylinder; the maximum compression pressure in the cylinder and pressure of the beginning of combustion of fuel; rpmmean, rpmmax - average and maximum crankshaft rpm for the chosen period; speed of pressure increasing and a rate of its increase at combustion; fuel timing (a angle of advancing and duration of fuel injection); valves timing, and as to some derivative parameters.
Distinctive features of system DEPAS 4.0 Handy:
1. TDC definition and data synchronization by our software (unique high-math algorithm (PSA) is used, thoroughly tested in portable systems DEPAS 2.34sp), any connection to crankshaft is unnecessary;
2. Valves, fuel timing and technical condition of separate units of the engine are determined with the help of contact vibrosensor VS-20. The most important advantage and the unique feature of the system is that definition of these parameters occurs without fitting of any valves into high pressure fuel system. The vibrosensor has a magnetic basis; it is convenient during diesel engine operation as it is unnecessary to use any tools for its fastening
Use of DEPAS D3… systems of monitoring enables to receive the following advantages in diesel engines operation:
- to save fuel, due to exact adjustment of fuel injection equipment and valve timing mechanism;
- to increase operational period between repairs and to reduce expenses for diesel engines service;
- to increase substantially safety of ship diesel engines operation;
- to save money – our system is considerably cheaper in price that systems of other makers but has more functionality.


SC 1.6 Screenshots SC 1.6

SC 1.6 system allows to perform remote monitoring of ship power installation working parameters. It is possible local (on a vessel) or remote (through the Internet) monitoring.

SC 1.6 carries out the chronological control of engine load and fuel consumption over various operating modes of Main Engines for the accounting period. ME operating modes data recording is performed continuously during all vessel operation period.
SC 1.6 structure and an information transfer way: the onboard, intellectual, closed database under the control of industrial controller RCM2000 (Rabbit Semiconductor).
Reading of the information is made by means of automatic data transmission.
The external software DEPAS SC 1.6 (Linux, Windows 95/98/NT/2000/XP) is established on a server and on computers of company corresponding departments.
Server accumulates the data saved by SC 1.6 and allows supervising ME operating modes, load and fuel consumption during the accounting period. For information processing vessel trial report data is used, or(and) before SC 1.6 installation ME control tests with the help of one of portable DEPAS systems are performed. The information for the accounting periods of ME operation of various ships collects in the common database in a company technical department, with an opportunity of carrying out the general fuel consumption analysis during any chosen period of fleet operation (day, month, voyage, year, etc.).
The system allows to supervise ship power plant operation parameters that will enable to perform registration of ME actual load and fuel consumption.

Depas 2.34sp
DEPAS 4.0 Handy
SC 1.6

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