Increased fuel consumption
A rise in fuel consumption at unchanged load and route is a consequence of a drop in the indicated efficiency of the engine. The register contains 30 industrial-test cases; the median reduction in fuel consumption is 12 %.
The upper bound of the range corresponds to engines with the highest accumulated running hours, whose initial consumption substantially exceeded the manufacturer's norm.
Causes of increased consumption
Fuel economy is determined by the share of released heat converted into work at the crankshaft. Wear reduces this share in two ways at once: part of the charge is lost through leaks, and part of the work obtained is spent on overcoming increased friction.
Mechanics of excess consumption
- Loss of combustion chamber tightness. Wear of the piston rings and the cylinder liner surface reduces the end-of-compression pressure. Combustion temperature and completeness fall, part of the fuel is not utilised, and the smoke opacity of the exhaust gases increases.
- Increase in mechanical losses. Enlarged clearances in the crankshaft bearings, wear of the valve train and of the driven units raise the share of power expended on the engine's own friction.
- Shift of the operating point. With reduced power, the same amount of work is performed at increased fuel delivery and in a less economical zone of the performance map. Specific consumption rises faster than power declines.
Measurement procedure
Consumption is compared under comparable operating conditions: identical route and payload for vehicles, identical load and duration for stationary installations. Control runs and shift operating hours are recorded in documents, the refuelling volume — by meter or measuring vessel.
For stationary units the indicative parameter is specific consumption referred to the power produced — it is independent of shift duration and permits measurements to be compared with one another.
Treated assemblies
Consumption was recorded for the unit as a whole; treatment was applied to the cylinder-piston group, the crankshaft bearings and the fuel injection equipment.
Equipment types
Test reports
Fifteen test reports with the maximum recorded reduction out of 19 containing a direct measurement of consumption. The full list is given in the catalogue.
| ENTERPRISE | YEAR | CHANGE | PARAMETER MEASURED |
|---|---|---|---|
| Gavrilenko V. D. Peasant Farm | 2008 | ↓ 17% | fuel consumption at idle, 100 ml in 3 min 25 s → 4 min 06 s |
| Gavrilenko V.D. Farm Enterprise | 2008 | ↓ 15.4% | fuel consumption at idle, 1.88 → 1.59 l/h |
| Taxi Moy Gorod LLC | 2018 | ↓ 15.2% | fuel consumption, 11.2 → 9.5 l |
| OJSC YuGOK, Kryvyi Rih | 2000 | ↓ 15% | fuel consumption at idle, 8.95 → 7.6 l/h |
| OJSC “YuGOK”, Kryvyi Rih | 2000 | ↓ 15% | locomotive fuel consumption at idle |
| Ukrzaliznytsia, Shevchenko depot | 2003 | ↓ 14.5–25% | fuel consumption at idle, 108 → 81 l/h on the D1 diesel train |
| SE “Ukrvodput” | 2001 | ↓ 11.6% | fuel consumption under load, 21.5 → 19.0 kg/h |
| STIROL Concern OJSC | 1999 | ↓ 11.5–13.5% | fuel consumption of both trucks, 100 ml burned in 45 → 52 and 100 → 113 s |
| REDLINE PERFORMANCE | 2003 | ↓ 11.5% | fuel consumption at idle, 700 ml in 29 min 37 s → 33 min 27 s |
| JSC “JV Rosava” | 2004 | ↓ 9.5% | fuel consumption at idle, 95 → 105 s per measuring vessel |
| University of Belgrade, Eng. Faculty | 2003 | ↓ 9.3% | fuel consumption in the urban cycle, 12.95 → 11.75 l/100 km |
| ChAAP “Promin” | 2012 | ↓ 8% | fuel consumption at idle, 100 ml of fuel in 2 min 20 s → 2 min 33 s |
| SE “Prydniprovska Zaliznytsia”, TCh-8 depot | 2009 | ↓ 7–12% | daily fuel consumption, 1023–1055 → 899–960 kg per locomotive |
| Tatneft JSC, Almetyevsk TTD-1 | 2001 | ↓ 6–13% | petrol consumption, measured on a metered 100 g portion of fuel |
| Universalneftekhim Lab, VTII LLC | 2014 | ↓ 2.95% | fuel consumption, highway cycle, 25.8 → 25.1 l/100 km |
All 30 cases in the catalogue →
Documents of the cases with a direct measurement: plant commission reports — 13, signed test protocols — 4, other documents — 2; the document type is stated on the case card.
Limits of data applicability
- Applicability. The figures relate to the equipment and operating conditions of the enterprises named in the reports; on a different unit the result depends on initial wear, load and oil.
- Source document. A scan of the original report is published under every case; if the card and the scan disagree, the scan is authoritative.