Prevention of vehicle windscreen fogging by means of automatic climate control when driving

Introduction (problem statement and relevance). A great deal of attention is paid to the problem of increasing the effi ciency of automatic control of glass fogging. Hundreds of research and studies have been carried out, and a great deal of papers by American, Japanese, Korean, European, Chinese, Iranian and other authors have been published within this topic. The ability of the vehicle HVAC system to automatically detect and prevent potential windscreen fogging improves safety. Less obvious is that it allows reduction of energy costs (prevention of fogging is more energy saving than removal of condensate) and also wider use of the means available in the vehicle, the usage of which usually leads to fogging problems. The paper describes the principles of automatic prevention of windscreen fogging by means of the vehicle HVAC system when driving. It also considers the strategies of early forecasting of fogging and automatic prevention of condensation that are comfortable for the driver and passengers.
The purpose of the study is to increase the efficiency of automatic control of windscreen fogging by means of the vehicle HVAC system.
Methodology and research methods. Study of methods to assess the risk of vehicle glass fogging and to prevent it automatically. Analysis of the related scientifi c literature, technical documentation and materials published in open sources; bench experiments and fi eld tests.
Scientific novelty and results. Automatic operation of the HVAC system in the vehicle windscreen fogging prevention mode when driving was considered. The scientific novelty consists in the suggested method of forecasting the risk of fogging and advanced control including simplifi ed calculation of the air dew point in the cabin, digital extrapolation of the risk level and corresponding advanced stage-by-stage correction of the HVAC system actuator control signals ensuring prevention of possible fogging.
Practical signifi cance. Preliminary checking under the winter field test conditions has shown the efficiency of the proposed method of windscreen fogging prevention compared to the typical way of controlling the risk of fogging. Further research is planned to obtain quantitative indicators of efficiency and economy of the proposed method.

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