AixLib.DataBase.CHP.ModularCHPEngineData.CHPEngDataBaseRecord

# .AixLib.DataBase.CHP.ModularCHPEngineData.CHPEngDataBaseRecord

Base record for CHP engine data

## Information

#### Overview

Data base record for CHP power units. The nominal / rated operation point most likely corresponds to the given full load performance.

#### Requirements

These quantities must be known for reliable simulation (by value, variable relation etc.):

- Heat and Power: Q_MaxHea, etaCHP(Hi)

- Engine Geometry: hStr, dCyl, z, i

- Generator specification: p or n0, n_nominal, U_1, P_elNominal, f_1

- Lambda or xO2Exh: Required for calculation of the engine combustion, heat flow and the exhaust gas composition (Lambda = 0.21 / (0.21 - xO2Exh))

- nEngNominal

- dInn (typical values around 0.005m, important for heat transfer from engine to cooling)

#### Default values and variable relations

These are the default values or relations in case that there is no information available:

- nEngMax: Engine speed at full load (=nEngNominal)

- etaGen: Generator efficiency (default=0.92)

- I_elNominal (=P_elNominal/(sqrt(3)*U_1*cosPhi))

- P_mecNominal (=P_elNominal/etaGen)

- P_FueNominal (=(P_elNominal+Q_MaxHea)/etaCHP)

- VEng (default=0.25*hStr*Modelica.Constants.pi*dCyl^2*z)

- mEng (default=70389*VEng+17.913, for first appraisal of the heat capacities of engine housing, should be calibrated)

- eps (typical values around 12 (SI) and 21 (DI))

- T_ExhPowOut (default=373.15K)

- gearRatio (default=1)

- cosPhi (default=0.8)

- useGenHeat (default=false)

- Exhaust and Coolant: dExh(default=0.06m), dCoo(default=0.04m), dp_Coo(default=0.15bar), m_flowCooNominal(default=0.00003*Q_MaxHea-0.2043)

- Engine material: lambda, rhoEngWall, c (default is cast iron(most common))

## Contents

Name | Description
--- | ---
RotationSpeed |
AirRatio |

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