# An Investigation of the Composition of the Flow in and out of a Two-Stroke Diesel Engine and Air Consumption Ratio

^{1}

^{2}

^{*}

## Abstract

**:**

_{stoich}. In this work, this was called the Air Consumption Factor or Ratio, and has not previously been mentioned in scientific literature. The air consumption ratio is defined as a factor of dry or humid air. To be more comprehensive, a modified diagram of the composition of the flow in and out of a two-stroke fuel injection engine and the cylinder was made.

## 1. Introduction

_{x}emissions and the reduction in fuel consumption. By implementing a waste heat recovery system through the use of an organic Rankine cycle and also a hybrid turbocharger, the fuel consumption and NO

_{x}emissions were lowered by up to 9% and 6.5% respectively. Andreadis et al. [16] used a large two-stroke marine diesel engine, operating at its full load to explore pilot injection strategies using simulations of computational fluid dynamics along with an evolutionary algorithm. Guan et al. [17] used a modular zero-dimensional engine model that was built in MatLab and the Simulink environment, to investigate the operation of a large two-stroke marine diesel engine. Engine shop trial values were compared with the derived performance parameters of the engine, which was simulated at steady state conditions. The study purpose of Varbanets et al. [18] was to record the methods by which the ship’s diesel process efficiency could be improved. Under the conditions of the fuel equipment and the normal state of the main diesel system, even load distribution between the cylinders was controlled. From previous research, the authors investigated the possibility of increasing efficiencies of a low speed two-stroke turbocharged main diesel engine operating with waste heat recovery through combined heat and power production [19,20]. Spahni et al. [21] in particular deals with new electronically controlled, two stroke, low speed marine engines. Carlucci et al. [22] compared different architectures (single turbocharger, double turbocharger, single turbocharger with an electrically-assisted turbocharger, with intercooler or aftercooler) designed to supercharge an aircraft two-stroke Diesel engine for general aviation and unmanned aerial vehicles characterized by very high altitude operation and long fuel distance. A 1D model of the purposely designed engine has been used to compare the performance of different supercharging systems in terms of power, fuel consumption, and their effect on trapping and scavenging efficiency at different altitudes. In [23], Carlucci et al. provided several guidelines about the definition of design and operation parameters for a two-stroke two banks uniflow diesel engine, turbocharged with two sequential turbochargers and an aftercooler per bank, with the goal of either increasing the engine braking power at take-off, or decreasing the engine fuel consumption at cruise conditions. The engine has been modelled with a 0D/1D modelling approach. Wang et al. [24] evaluated scavenge port designs for a boosted uniflow scavenge direct injection gasoline engine by 3D computational fluid dynamics (CFD) simulations. In order to fulfil the potential of the boosted uniflow scavenged direct injection gasoline (BUSDIG) engine, various scavenge ports were designed with different scavenge port numbers, axis inclination angles and swirl orientation angles, and their effects were evaluated by 3D CFD under different intake pressures and engine speeds. The scavenging process was analysed by its delivery ratio, trapping efficiency, scavenging efficiency and charging efficiency.

_{max}as a reference volume, which is more appropriate for two-stroke engines. For the purpose of connecting the air consumption ratio with two-stroke gas performance parameters, we proposed an improved version of the figure—the composition of the flows in and out a two-stroke engine and its cylinder. We also found that air consumption ratio depended on ratio of the excess air in the cylinder, and the trapping efficiency.

## 2. Engine Model Description

_{1}and T

_{2}[26].

_{0}and in this case the environment is the atmosphere and sea water. The heat from the cylinder liner, cylinder cover, lubricating oil and scavenged air is removed by cooling water. The reference state of the environment is standard state; 25.0 °C and 1.00 bar. At steady state conditions the continuity equation is ${\dot{m}}_{\mathrm{in}}={\dot{m}}_{\mathrm{out}}$.

_{x}is the exergy expended per kilogram of input or output substance.

_{2}O in the combustion products was in the vapour state, and the higher caloric value if the H

_{2}O in the combustion products was in the liquid state.

_{0}and the pressures equal to their partial pressures in the atmosphere. In that case, $s{*}_{\mathrm{products}}\approx s{*}_{\mathrm{reactants}}$ with ${\left[\Delta H\xb4\right]}_{{T}_{0},{p}_{0}}$ is equal to fuel a higher caloric value. It follows that for these fuels, ${w}_{\mathrm{tehn},\mathrm{max}}^{*}\approx {\left[\Delta H\xb4\right]}_{{T}_{0},{p}_{0}}$. For pure carbon, lower and higher caloric values are the same; for hydrogen, ${w}_{\mathrm{tehn},\mathrm{max}}^{*}=0.823{\left[\Delta H\prime \right]}_{{T}_{0},{p}_{0}}$. For gaseous hydrocarbons, ${w}_{\mathrm{tehn}.\mathrm{max}}^{*}$ is slightly lower in percentage than ${\left[\Delta H\xb4\right]}_{{T}_{0},{p}_{0}}$. But since in practice, the full amount of ${w}_{\mathrm{tehn}.\mathrm{max}}^{*}$ is very difficult to achieve, the exergy efficiency calculated as η

_{ex=}w*

_{tehn}/H

_{d}will be used for the purpose of comparison.

#### 2.1. Data MAN B&W CEAS_ERD (Engine Room Dimensioning)

Bore = 700 mm | Stroke = 2800 mm | s/d=4.0 | c_{m} = 8.5 m/s |

SMCR L_{1}: | n = 91 min^{−1} | p_{me}=19.0 bar | NMCR = 18,660 kW |

^{−1}and marked by point L

_{1}on Figure 2.

_{1}–L

_{3}and L

_{2}–L

_{4}are isobars and referred to the respective mean effective pressure p

_{me}, and lines L

_{1}–L

_{2}& L

_{3}–L

_{4}are isotachs and related to the constant speed n, of the engine. The blue curve that passes through the point L1 is the heavy propeller curve, and it is expected that the voyage of the ship will mainly reflect the actual conditions of navigation as hull fouling (covered by shells and algae), and environmental conditions (waves, wind, ocean currents, etc.).

^{−1}, and Service Power or NCR is taken to be 80% SMCR, which is 14,928 kW at 84.5 min

^{−1}.

#### 2.2. The Flow of Substances through the Engine

_{e,c.o.}is 0.60 g/kWh at all engine loads. From Table 2 is obvious that scavenged air cooler heat had great potential, especially at higher engine loads.

_{ws}= water saturation pressure [Pa], p=humid air pressure [Pa], and p

_{p}= partial vapor pressure [Pa].

#### 2.3. Calculation of Combustion Based on Fuel, Cylinder Oil and Air Consumption

#### **AIR**

#### **FUEL**

#### **CYLINDER** **OIL**

#### **Calculation of the** **amount of unburnt fuel and cylinder oil in exhaust gases**

#### **Emissions** **and unburnt fuel in the exhaust gases**

- 1500 vppm NO
_{x}(90% ÷ 95% NO and 5% ÷ 10% NO_{2}) - 70 ppm SO
_{x} - 60 ppm CO
- 180 ppm HC$${\dot{E}}_{\mathrm{f}\text{}\mathrm{unburnt}}={\dot{m}}_{\mathrm{f}\text{}\mathrm{unburnt}}\cdot \Delta H{\xb4}_{{T}_{0},{p}_{0}}\text{}\mathrm{kJ}/\mathrm{s}$$$$\mathrm{\%\; fuel\; unburnt}=\frac{sm{f}_{\mathrm{f}\text{}\mathrm{unburnt}}}{{b}_{\mathrm{e}}}\cdot 100=0.962482658\text{}\%$$$$\mathrm{\%\; unburnt\; fuel\; and\; cyl\; oil}=\frac{sm{f}_{\mathrm{HC}\text{}\mathrm{t}\text{}\mathrm{unburnt}}}{{b}_{\mathrm{e}}+{b}_{\mathrm{c}.\mathrm{o}.}}\cdot 100=1.298610269\text{}\%$$N + O → NO
- The stoichiometric amount of oxygen required for combustion:C + O
_{2}→ CO_{2}H_{2}+1/2 O_{2}→ H_{2}OS + O_{2}→ SO_{2}

#### 2.4. Air Consumption Ratio/Factor

_{2}/kWh, this will be a set ratio with the amount of O

_{2}in dry air.

_{2}and other components in air (N

_{2}and Ar) in kg/kWh necessary for ideal stoichiometric combustion of 0.1709 kg/kWh fuel can be calculated.

_{stoich}for fuel combustion (without cylinder oil):

#### 2.5. Calculation of Exhaust Gas Composition Using NIST Refprop09

#### 2.6. The Composition of the Flow in and out of a Two-Stroke Engine and the Cylinder

- p
_{sc}= scavenge air pressure at the entrance of scavenging ports - T
_{sc}= scavenge air temperature at the entrance of scavenging ports - T
_{s}= gas temperature in cylinder at the end of scavenge process - ${\dot{m}}_{\mathrm{sc}}=\mathrm{mass\; of\; air\; delivered\; to\; engine\; at\; pressure}\text{}{p}_{\mathrm{sc}}\text{}\mathrm{and\; temp}.\text{}{T}_{\mathrm{sc}}\text{}\mathrm{per\; sec}$
- m
_{sc,h}= mass of humid air delivered to the cylinder/cycle at pressure p_{sc}and temperature T_{sc} - m
_{sc,d}= mass of dry air delivered to the cylinder/cycle at pressure p_{sc}and temperature T_{sc} - m
_{a,H2O}= mass of water delivered with humid air to the cylinder/cycle at pressure p_{sc}and temperature T_{sc} - m
_{ar}= mass of fresh air retained in the cylinder/cycle - m
_{ar,t}= total air mass in the cylinder/cycle after scavenging port closed (SC) and exhaust valve closed (EC) - m
_{r}= residual mass of gases in the cylinder/cycle - m
_{rp}= residual (recirculated) mass of products in the cylinder/cycle - m
_{tr}= m_{ar}+ m_{r}= mass of trapped charge (fresh air and residual gas in the cylinder/cycle) after SC and EC - m′ = mass of air that could be caught in the cylinder/cycle at a pressure p
_{sc}and a temperature T_{sc} - m
_{a.d. stoich}= mass of dry air required for stoichiometric combustion in the cylinder/cycle - m
_{a.h. stoich}= mass of humid air required for stoichiometric combustion in the cylinder/cycle - m
_{a,excess}= excess air in the cylinder/cycle - m
_{a.d.,s–c}= mass of dry air, direct blowout from cylinder/cycle - m
_{f}= the mass of fuel injected into the cylinder/cycle - m
_{co}= the mass of cylinder oil injected into the cylinder/cycle - m
_{a.d. out}= the total mass of the dry air at the outlet of the cylinder/cycle - m
_{p}= mass products of combustion at the exit from the cylinder/cycle (including moisture from the air and emissions) - m
_{exh}= the total mass of the exhaust gas at the outlet of the cylinder/cycle - ${m}_{\mathrm{sc}}=\frac{{\dot{m}}_{\mathrm{sc}}}{(n/60)\cdot z}\text{}$
- ${m}^{\prime}={V}_{\mathrm{max}}\cdot {\rho}_{\mathrm{sc}}={V}_{1}\cdot {\rho}_{\mathrm{sc}}$
- m
_{p}= m_{react}= m_{a,d. stoich}+ m_{a,H2O}+ m_{f}+ m_{co} - m
_{exh}= m_{sc,h}+ m_{f}+ m_{co}= m_{p}+ m_{a.d.out}

- (a)
- Delivery ratio (Scavenge ratio) Λ
_{d}:$${\Lambda}_{\text{}\mathrm{d}}=\frac{\mathrm{mass\; of\; delivered\; air}}{\mathrm{reference\; mass}}=\frac{{m}_{\mathrm{sc}}}{{m}^{\prime}}=\frac{{m}_{\mathrm{sc}}}{{V}_{1}\cdot {\rho}_{\mathrm{sc}}}$$

- (b)
- Charging efficiency η
_{ch}:$${\eta}_{\mathrm{ch}}=\frac{\mathrm{mass\; of\; delivered\; air\; retained}}{\mathrm{reference\; mass}}=\frac{{m}_{\mathrm{ar}}}{{m}^{\prime}}=\frac{{m}_{\mathrm{ar}}}{{V}_{1}\cdot {\rho}_{\mathrm{sc}}}$$This shows how successfully the cylinder volume is filled with fresh air. - (c)
- Scavenging efficiency η
_{sc}:$${\eta}_{\mathrm{sc}}=\frac{\mathrm{mass\; of\; delivered\; air\; retained}}{\mathrm{mass\; of\; trraped\; cylinder\; charge}}=\frac{{m}_{\mathrm{ar}}}{{m}_{\mathrm{ar}}+{m}_{\mathrm{r}}}=\frac{{m}_{\mathrm{ar}}}{{m}_{\mathrm{ar},\mathrm{t}}+{m}_{\mathrm{rp}}}$$

_{r}are replaced by a fresh charge m

_{ar}.

_{ar,t}, the mass of burnt gas, and the mass of unburnt fuel from previous cycle m

_{rp}.

- (d)
- Retaining Efficiency η
_{rt}:$${\eta}_{\mathrm{rt}}=\frac{\mathrm{mass\; of\; delivered\; air\; retained}}{\mathrm{mass\; of\; delivered\; air}\text{}/\text{}\mathrm{cycle}}=\frac{{m}_{\mathrm{ar}}}{{m}_{\mathrm{sc}}}$$This shows how much air comes directly to the exhaust.The charging efficiency can be defined in terms of the delivery ratio and retaining efficiency:$${\eta}_{\mathrm{ch}}={\Lambda}_{\text{}\mathrm{d}}\cdot {\eta}_{\mathrm{rt}}$$

- (e)
- Trapping efficiency η
_{tr}$${\eta}_{\mathrm{tr}}=\frac{\mathrm{mass\; of\; trapped\; air\; charge}}{\mathrm{mass\; of\; delivered\; air}\text{}/\text{}\mathrm{cycle}}=\frac{{m}_{\mathrm{ar},\mathrm{t}}}{{m}_{\mathrm{sc}}}$$

- (f)
- Relative charge (Volumetric efficiency) Λ
_{tr}:$${\Lambda}_{\text{}\mathrm{tr}}=\frac{\mathrm{mass\; of\; trapped\; cylinder\; charge}}{\mathrm{reference\; mass}}=\frac{{m}_{\mathrm{tr}}}{{m}^{\prime}}=\frac{{m}_{\mathrm{tr}}}{{V}_{1}\cdot {\rho}_{\mathrm{sc}}}$$

_{tr}(or a close approximation of it), then:

- (g)
- Air-fuel ratio (AFR) for stoichiometric fuel combustion:$$AF{R}_{\mathrm{stoich}}=\frac{{m}_{\mathrm{a}\text{}\mathrm{stoich}}}{{m}_{\mathrm{f}}}=\frac{{\dot{m}}_{\mathrm{a}\text{}\mathrm{stoich}}}{{\dot{m}}_{\mathrm{f}}}$$

- (h)
- The excess air in the cylinder, and the relative ratio Λ
_{excess}is:$${\Lambda}_{\text{}\mathrm{excess}}=\frac{{({m}_{\mathrm{a}}/{m}_{\mathrm{f}})}_{\mathrm{actual}}}{{({m}_{\mathrm{a}}/{m}_{\mathrm{f}})}_{\mathrm{stioch}}}=\frac{{m}_{\mathrm{ar},\mathrm{t}}}{{m}_{\mathrm{a}.\mathrm{h}.\text{}\mathrm{stoich}}}=\frac{{m}_{\mathrm{a}.\mathrm{h}.\text{}\mathrm{stoich}}+{m}_{\mathrm{a},\mathrm{excess}}}{{m}_{\mathrm{a}.\mathrm{h}.\text{}\mathrm{stoich}}}$$

- (i)
- The air Consumption Factor/Ratio ${\Lambda}_{\mathrm{AC}}$:$${\Lambda}_{\mathrm{AC}}=\frac{\mathrm{mass\; of\; air\; delivered}/\mathrm{cycle}}{\mathrm{mass\; of\; air\; necessary\; for\; stoichometric\; fuel\; combustion}/\mathrm{cycle}}=\frac{{m}_{\mathrm{sc}}}{{m}_{\mathrm{a}\text{}\mathrm{stoich}}}$$$${\Lambda}_{\mathrm{AC}}=\frac{{m}_{\mathrm{sc}}}{{m}_{\mathrm{a}\text{}\mathrm{stoich}}}=\frac{{m}_{\mathrm{sc}}\cdot {m}_{\mathrm{ar},\mathrm{t}}}{{m}_{\mathrm{ar},\mathrm{t}}\cdot {m}_{\mathrm{a}\text{}\mathrm{stoich}}}=\frac{{\Lambda}_{\mathrm{excess}}}{{\eta}_{\mathrm{tr}}}$$

## 3. Results and Discussion

_{2}content in the exhaust gases. As of 14 March 2011, from MAN Diesel & Turbo data, modern 6SME-C diesel engines have emissions of only 0.3 g/kWh CO and 0.4 g/kWh HC. In the engine reported on here, total unburnt hydrocarbons from fuel and cylinder oil in SMCR was 2.227 g/kWh (HC, CO, soot), of which the fuel was only 1.645 g/kWh. Results of our calculations are presented in Table 3, Table 4, Table 5, Table 6, Table 7 and Table 8.

_{actual}and stoichiometric air consumption change with main engine loads. Actual (total) AFR was very close to the results presented in the work of Guan et al. [29] for the main engine load from 50 to 100% SMCR.

_{x}, CO, HC and particles when using HFO were very close to the actual values of the MDO fuel, for which our calculation was made. This assumes that all the cylinder lubricating oil entered and burned in the combustion chamber, and the small percentage that was scraped by the piston rings and remained below the piston was negligible.

_{x}and SO

_{x}in the exhaust gases was ignored, while unburnt HC and soot (C) in the calculation was taken over hexane whose calorific value approximately corresponded to the calorific value of MDO. In order to simplify the exhaust gas calculation, SO

_{2}was included in CO

_{2}. Results of our calculation for volume/molar composition are shown in Figure 9 for 100% SMCR engine load. Table 9 shows the exhaust gas composition over 50% to 100% of main engine load.

_{2}and H

_{2}O as expected. The oxygen proportion in the exhaust gas was high and ranged from 15.73% (50% SMCR) to 14.78% (100% SMCR). The main reason was a short circuiting of air during the gas exchange process. The high consumption of air helps to clean exhaust gases in the cylinders, but also lowers the temperature of the exhaust gases, whose energy could be used in the WHR system. It also requires a higher capacity turbocharger. At the service power (80% SMCR), the engine consumed four times more air than is required for stoichiometric fuel combustion.

## 4. Conclusions

_{s}is used as a reference volume in literature, we used V

_{max}for two stroke engines, which is much more appropriate.

_{x}formation. Better trapping efficiency can be achieved by decreasing the mass of air in the direct blowout cylinder. By measuring and calculating the air consumption ratio and relative ratio, trapping efficiency can be calculated.

## Acknowledgments

## Author Contributions

## Conflicts of Interest

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**Figure 2.**The quad of mean effective pressure and engine speed with chosen nominal continuous rating (NCR) [27].

**Figure 3.**Schematic diagram of the conventional main engine 6S70MC-C7 for ISO conditions and 100% specified maximum continuous rating (SMCR).

**Table 1.**SFOC and exhaust gases data, ISO conditions [27]. SFOC: specific fuel oil consumption; ISO: International Organization for Standardization; temp.: Temperature.

Load % SMCR | Power (kW) | Speed (min^{−1}) | SFOC (g/kWh) | Exhaust Gas Amount (kg/h) | Exhaust Gas Temp. (°C) |
---|---|---|---|---|---|

100 | 18,660 | 91.0 | 170.9 | 172,800 | 240.5 |

95 | 17,727 | 89.5 | 168.8 | 166,200 | 235.6 |

90 | 16,794 | 87.9 | 167.1 | 159,600 | 232.0 |

85 | 15,861 | 86.2 | 165.6 | 152,900 | 229.7 |

80 | 14,928 | 84.5 | 164.4 | 146,000 | 228.8 |

75 | 13,995 | 82.7 | 163.5 | 138,900 | 229.1 |

70 | 13,062 | 80.8 | 162.9 | 131,500 | 230.8 |

65 | 12,129 | 78.8 | 162.9 | 123,800 | 233.7 |

60 | 11,196 | 76.8 | 163.3 | 115,800 | 238.0 |

55 | 10,263 | 74.6 | 163.9 | 107,500 | 243.6 |

50 | 9330 | 72.2 | 164.8 | 98,800 | 250.5 |

**Table 2.**Heat exchanger power at various engine loads, ISO conditions [27].

1 Engine Load (% SMCR) | 2 Engine Power (kW) | 3 Engine Speed (r/min) | 4 Scavenge Air Amount +/−5% (kg/h) | 5 Scavenge Air Pressure (bar abs) | 6 Scavenge air Temperature before Air Cooler (°C) | 7 Scavenge Air Temperature after Air Cooler (°C) | 8 Scavenge Air Cooler Heat (kW) | 9 Jacket Water Cooler Heat −15/+0% (kW) | 10 Main Lubrication Oil Heat (kW) |
---|---|---|---|---|---|---|---|---|---|

ISO Ambient Conditions Air Suction Temperature: 25.0 °C; Cooling Water Temperature: 25.0 °C | |||||||||

1 % | 2 kW | 3 r/min | 4 kg/h | 5 bar(abs) | 6 °C | 7 °C | 8 kW | 9 kW | 10 kW |

100 | 18,660 | 91.0 | 169,600 | 3.79 | 193.0 | 37.0 | 7420 | 2390 | 1260 |

95 | 17,727 | 89.5 | 163,200 | 3.62 | 186.0 | 36.0 | 6890 | 2290 | 1240 |

90 | 16,794 | 87.9 | 156,800 | 3.45 | 179.0 | 34.0 | 6360 | 2200 | 1220 |

85 | 15,861 | 86.2 | 150,300 | 3.28 | 172.0 | 33.0 | 5840 | 2100 | 1200 |

80 | 14,928 | 84.5 | 143,500 | 3.11 | 164.0 | 32.0 | 5310 | 2010 | 1180 |

75 | 13,995 | 82.7 | 136,600 | 2.94 | 156.0 | 31.0 | 4790 | 1920 | 1160 |

70 | 13,062 | 80.8 | 129,400 | 2.77 | 148.0 | 30.0 | 4270 | 1830 | 1130 |

65 | 12,129 | 78.8 | 121,800 | 2.60 | 139.0 | 29.0 | 3750 | 1730 | 1100 |

60 | 11,196 | 76.8 | 114,000 | 2.43 | 130.0 | 29.0 | 3250 | 1640 | 1070 |

55 | 10,263 | 74.6 | 105,800 | 2.26 | 121.0 | 28.0 | 2750 | 1550 | 1040 |

50 | 9330 | 72.2 | 97,300 | 2.09 | 111.0 | 27.0 | 2270 | 1460 | 1000 |

Substance | $\dot{\mathit{m}}$ (kg/s) | b_{e} (kg/kWh) | g_{c} (%) | g_{h} (%) | g_{s} (%) | g_{CA} (%) |
---|---|---|---|---|---|---|

Fuel | 0.8858317 | 0.1709 | 85.76 | 13.82 | 0.42 | - |

Cyl. oil | 0.00311 | 0.0006 | 83.60 | 13.40 | 0.50 | 2.5 |

Cyl. Oil HC | 0.0030167 | 0.000582 | 86.18 | 13.82 | - | - |

Substance | $\dot{\mathit{m}}$ (kg/s) | smf (kg/kWh) | gN_{2} (%) | gO_{2} (%) | gAr (%) | gH_{2}O (%) |
---|---|---|---|---|---|---|

Humid air | 47.1111 | 9.08896 | 75.1187 | 23.02169 | 1.2615 | 0.597175 |

Dry air | 46.829775 | 9.03468332 | 75.57 | 23.16 | 1.2691 | - |

H_{2}O in air | 0.281336 | 0.054277 | - | - | - | - |

**Table 5.**Fuel composition and stoichiometric oxygen consumption for fuel and cylinder oil combustion at 100% SMCR, ISO standard conditions.

Molar Composition (kmol/kWh) | C | H_{2} | S | Σ |
---|---|---|---|---|

Proportion of components in the fuel, N kmol/kWh | 0.012202468 | 0.011716047 | 0.0000223886 | 0.023940904 |

The oxygen consumption for the fuel combustion, N kmol O_{2}/kWh | 0.012202468 | 0.005858024 | 0.0000223886 | 0.01808288 |

The oxygen consumption for the complete combustion of fuel and cyl. oil, N kmol O_{2}/kWh | 0.012244227 | 0.005877973 | 0.0000223886 | 0.018144589 |

The oxygen consumption for 98.7% fuel and cylinder oil combustion, N kmol O_{2}/kWh | 0.012078002 | 0.005820837 | - | - |

Products after complete combustion, N kmol/kWh | 0.012244227 | 0.011755946 | 0.0000223886 | 0.024022562 |

Products after 98.7% combustion, N kmol/kWh | 0.012078002 | 0.011641673 | - | - |

Substance | Unit | O_{2} | N_{2} | Ar | Σ |
---|---|---|---|---|---|

Dry Air stoich | kg/kWh | 0.5786341 | 1.88798344 | 0.0317073 | 2.49832481 |

G | % | 23.16 | 75.57 | 1.2691 | 100 |

R | % | 20.96 | 78.12 | 0.92 | 100 |

Fraction in Exhaust Gas | C unburnt | H unburnt | C in CO_{2} | H in H_{2}O | S in SO_{2} | O_{2} burnt |
---|---|---|---|---|---|---|

Fraction in exh. Gas kmol/kWh | 0.000166 | 0.000114 | 0.012080 | 0.011640 | 0.000022 | 0.017920 |

Molar Composition | O_{2} | CO_{2} (+SO_{2}) | H_{2}O | Ar | N_{2} | H_{6}C_{14} |
---|---|---|---|---|---|---|

r | 0.147839424 | 0.037683715 | 0.045638029 | 0.008938867 | 0.759026424 | 0.000873541 |

$r\cdot M$ | 4.730713744 | 1.658460303 | 0.822169089 | 0.357089869 | 21.26260721 | 0.07527737 |

% SMCR | 50 | 60 | 70 | 80 | 90 | 100 |
---|---|---|---|---|---|---|

r_{O2} % | 15.72927012 | 15.65486 | 15.52668 | 15.31897 | 15.06865 | 14.78394245 |

r_{CO2} % | 3.170466448 | 3.217451 | 3.298467 | 3.42984 | 3.588208 | 3.768371514 |

r_{H2O} % | 3.991802162 | 4.036903 | 4.11451 | 4.240189 | 4.391613 | 4.563802879 |

r_{Ar} % | 0.896522031 | 0.896313 | 0.895954 | 0.895375 | 0.894678 | 0.893886725 |

r_{N2} % | 76.12641422 | 76.10865 | 76.0782 | 76.02904 | 75.96987 | 75.90264236 |

r_{emissions} % | 0.085525019 | 0.085829 | 0.086186 | 0.086585 | 0.086981 | 0.08735407 |

© 2017 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).

## Share and Cite

**MDPI and ACS Style**

Grljušić, M.; Tolj, I.; Radica, G.
An Investigation of the Composition of the Flow in and out of a Two-Stroke Diesel Engine and Air Consumption Ratio. *Energies* **2017**, *10*, 805.
https://doi.org/10.3390/en10060805

**AMA Style**

Grljušić M, Tolj I, Radica G.
An Investigation of the Composition of the Flow in and out of a Two-Stroke Diesel Engine and Air Consumption Ratio. *Energies*. 2017; 10(6):805.
https://doi.org/10.3390/en10060805

**Chicago/Turabian Style**

Grljušić, Mirko, Ivan Tolj, and Gojmir Radica.
2017. "An Investigation of the Composition of the Flow in and out of a Two-Stroke Diesel Engine and Air Consumption Ratio" *Energies* 10, no. 6: 805.
https://doi.org/10.3390/en10060805