Development of On-Board In-Cylinder Gas Flow Model for Heat Loss Estimation of Diesel Engines

Ichiyanagi, Mitsuhisa; Kojima, Kazuki; Joji, Hayao; Matsui, Hiroki; Suzuki, Takashi

doi:10.9744/jirae.3.2.69-78

Cited by 3 publications

(6 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These tools are used to compare and evaluate the performance of the developed model under steady and transient conditions in following sections. CFD was validated in the previous study [25] while the 1-D simulation is validated in this paper. Engine specifications are shown in Table 1.…”

Section: Numerical Simulation Setupmentioning

confidence: 99%

“…The gas composition is estimated by the gas composition model [28] to calculate the specific heat values. Then, with the gas flow model [25], the heat loss is estimated. The average wall surface temperature inside the combustion chamber (refer as wall temperature) is obtained, and lastly, the polytropic index is predicted.…”

Section: Model Outlinementioning

confidence: 99%

“…The discrete points represent the specific points of a common diesel cycle such as intake valve opening and closing timings (IVO and IVC) as well as exhaust valve opening and closing timings (EVO and EVC). Other points are selected to maintain the calculation accuracy of the gas flow model [25] while to minimize the computational load for onboard applications. From this section, each discrete point is referred as "point".…”

Section: Model Outlinementioning

confidence: 99%

“…To reduce the computational load of the model, the model does not calculate the turbulence. Instead, the turbulence intensity is estimated from gas flow velocities calculated by the developed gas flow model and turbulence intensity coefficients obtained by CFD [25]. Since various gas flows cause turbulence at different parts of the cylinder, the heat transfer is not uniform to the wall.…”

Section: Heat Lossmentioning

confidence: 99%

“…The authors had previously developed a theoretical heat loss model [24] based on the continuity equation and the law of conservation of energy, considering formulation of boundary layers inside the combustion chamber, while keeping the computational load low. To further improve the estimation accuracy, our previous study [25] developed a model for the gas flows inside the combustion chamber. The gas flow model determines flow velocities and turbulence intensities in the gas flows due to strong correlations between turbulence and heat transfer has been found [26].…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Development of On-board Polytropic Index Prediction Model for Injection Timing Optimization of Diesel Engines

Ichiyanagi

Joji

Matsui

et al. 2018

International Journal of Industrial Research and Applied Engineering

Self Cite

View full text Add to dashboard Cite

Diesel engines are required to reduce exhaust emissions during real-world operations. In this regard, a new control concept called model-based control has been explored. Unlike the conventional method of relying on steady-state measurements, model-based control allows cycle-bycycle optimization of control inputs based on physical principles. Existing models for combustion control have been using empirical equations to predict polytropic index for the compression stroke for estimation of in-cylinder pressure and temperature at fuel injection. Therefore, in this study, a polytropic index prediction model was developed in MATLAB to maintain the engine performance under transient conditions and to reduce the required number of experiments. The model includes a heat loss model and a gas flow model to consider the effect of wall heat transfer and gas flows inside the cylinder. The computational load of the model was reduced through discretization of a single engine cycle into several calculation points. The model was validated against numerical simulation results under steady conditions first, and then applied to transient conditions for more realistic operational conditions. The model estimated the polytropic index with average errors under steady and transient conditions with 0.22% and 0.37%, respectively. Finally, the calculation time of the model was evaluated to be 50.6 μs. It was concluded the model can be implemented on a model-based controller in the future.

show abstract

Section: Numerical Simulation Setupmentioning

confidence: 99%

Section: Model Outlinementioning

confidence: 99%

Section: Model Outlinementioning

confidence: 99%

Section: Heat Lossmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Development of On-board Polytropic Index Prediction Model for Injection Timing Optimization of Diesel Engines

Ichiyanagi

Joji

Matsui

et al. 2018

International Journal of Industrial Research and Applied Engineering

Self Cite

View full text Add to dashboard Cite

show abstract

Improvement of On-board In-cylinder Gas Flow Model and Wall Heat Transfer Prediction Model for CI Engines Using CFD Analysis and PIV Measurements under Motoring and Firing Conditions

Ichiyanagi,

Ndizeye,

Sawamura

et al. 2020

SAE Technical Paper Series

View full text Add to dashboard Cite

<div class="section abstract"><div class="htmlview paragraph">For the improvement of the transient driving performance and the thermal efficiency for diesel engines, it is effective to control the fuel injection by model-based control (MBC) on ECU with cycle-by-cycle calculation, and MBC requires six models; gas flow, spray development, mixture formation, combustion, ignition delay, and heat loss. The authors previously developed on-board in-cylinder gas flow and wall heat transfer prediction models to estimate the heat loss. However, the developed gas flow model has an undetermined coefficient called the turbulence intensity coefficient (TIC), which significantly influences the prediction accuracy of the wall heat transfer prediction model. The present study improved the gas flow model and the wall heat transfer prediction model by applying TICs obtained using the PIV and CFD analysis. In-cylinder gas flow in an optical single-cylinder diesel engine was measured by PIV under both motoring and firing conditions, and TICs were calculated and applied to the wall heat transfer prediction model. The heat flux values obtained from the model were compared with those from the experiments using heat flux sensors. It was made clear that the average heat flux using TIC at 60–80 mm plane (stroke of 96.9 mm) showed the least error of -4.7%, suggesting that the use of TIC at planes further away from the cylinder head better predicts the heat flux. For obtaining TICs without experiments, the similar calculation technique of TICs was applied to the CFD analysis, and thus, the relative error of heat flux with TIC estimated at the lower part of cylinder (60–96.9 mm) was -3.8%, which improved the prediction accuracy of the model using the CFD analysis.</div></div>

show abstract

Evaluation of On-board Heat Loss Prediction Model and Polytropic Index Prediction Model for CI Engines Using Measurements of Combustion Chamber Wall Heat Flux

Ichiyanagi,

Liu,

Chen

et al. 2020

SAE Technical Paper Series

View full text Add to dashboard Cite

<div class="section abstract"><div class="htmlview paragraph">Diesel engines need to optimize the fuel injection timing and quantity of each cycle in the transient operation to increase the thermal efficiency and reduce the exhaust gas emissions through the precise combustion control. The heat transfer from the working gas in the combustion chamber to the chamber wall is a crucial factor to predict the gas temperature in the combustion chamber to optimize the timing and quantity of fuel injection. Therefore, the authors developed both the heat loss and the polytropic index prediction models with the low calculation load and high accuracy. In addition, for the calculation of the heat loss and the polytropic index, the wall heat transfer model was also developed, which was derived from the continuity equation and the energy equation. The present study used a single cylinder diesel engine under the condition of engine speed of 1200 and 1500 rpm, and measured the local wall temperature and the local heat flux of the combustion chamber. The measured data were compared with the prediction results of the heat loss and the polytropic index and evaluated the prediction accuracy of those models. The average relative errors for the heat loss and the polytropic index prediction models were evaluated to be 6.6% and 0.3%, respectively.</div></div>

show abstract

Development of On-Board In-Cylinder Gas Flow Model for Heat Loss Estimation of Diesel Engines

Cited by 3 publications

References 29 publications

Development of On-board Polytropic Index Prediction Model for Injection Timing Optimization of Diesel Engines

Development of On-board Polytropic Index Prediction Model for Injection Timing Optimization of Diesel Engines

Improvement of On-board In-cylinder Gas Flow Model and Wall Heat Transfer Prediction Model for CI Engines Using CFD Analysis and PIV Measurements under Motoring and Firing Conditions

Evaluation of On-board Heat Loss Prediction Model and Polytropic Index Prediction Model for CI Engines Using Measurements of Combustion Chamber Wall Heat Flux

Contact Info

Product

Resources

About