Investigation of coking diesel injector spray nozzles in operation

Abstract

One of the significant problems in ensuring the reliable operation of the nozzles is the intensive coking of the injector spray nozzle ports. Based on the assumption that all fuel left by injection under the needle burns, some researchers believe that the reason for coking is insufficiently emptying of this volume. There is also a well-known opinion about the impact of atomization quality at the final phase of injection. The lack of consensus and conflicting recommendations on the issue make the research relevant. A set of investigations has been carried out at OJSC “TsNITA” to study the influence of various factors, including design factors of the fuel system, on the coking of injector spray nozzle ports. This article describes the investigation results carried out on the basis of test materials for 24 variants of fuel systems on the D-240 engine, the analysis of varying parameters for the injection final phase is carried out depending on the combination of design factors and the relationship of coking of the injector spray nozzle ports with the final phase parameters is shown.