Simulation of the heat accumulator operation of the internal combustion engine preheating system

Klara Luniaka,Oleh Kliuiev,Oleksandra Kliuieva,Serhii Rusanov,M Rerak,M Majdak

doi:10.1051/e3sconf/202132300023

Abstract

We considered the heat accumulator with a phase-transfer heat-accumulating material, which serves for pre-heating of the car’s internal combustion engine. Simulation of the heat accumulator operation allows to build calculated graphs of temperature change of the heat-accumulating material in time, and afterwards to determine the charging time of the heat accumulator depending on its design features, thus, by modelling the most optimal design solution. We performed numerical computations of the system engine – circulating fluid – heat storage material – environment in two stages. In the first stage, we calculated the parameters of thermal resistance in the engine system and pipe manifold for different coolant temperatures according to the method of finite volume in the CFD system. In the second stage the problem was solved numerically by the method of equivalent thermal circuit. We carried out phase transition simulation using the Stefan condition, based on the thermal balance for the phase separation surface. We constructed numerical algorithmic models for calculations of temperature change of heat-accumulating material in time. Such calculations allowed determining the optimal number of U-shaped tubes based on which we proposed the heat accumulator design. We manufactured the heat accumulator, tested, and proved its efficiency and positive effect on the engine warm-up time and the passenger compartment.

Highlights

When the ambient temperatures are low during prolonged parking, for example, at night, there are difficulties with starting the engine at the beginning of operation
Ozokerite was used as the heat storage material (HSM) and liquid of the engine cooling system – antifreeze as a heat carrier
We proposed this design based on the analysis of different types of heat accumulators, heat storage substances and heat carriers

Summary

Introduction

When the ambient temperatures are low during prolonged parking, for example, at night, there are difficulties with starting the engine at the beginning of operation (the so-called "cold start"). Cold start is characterized by decreasing engine life, increasing specific fuel consumption (according to various sources by 7-20%), the difficulty of ensuring the starting speed of the crankshaft, deteriorating of the conditions of mixture formation and flame formation of the air-fuel mixture. It is caused by decreasing temperature of motor oil, fuel, the storage battery, details of the engine and features of its starting properties. In this regard, attention is paid to creating favorable conditions for starting the car engine in the cold season

Methods

Results

Conclusion