| The solar air heat collector plays a crucial role in the solar alfalfa drying device,especially in whether the solar power can be fully used,and therefore has significant importance in the quality of the dried alfalfa and the cost of the drying process.This paper we tested different solar air heat collectors’ heat-collecting efficiency and contracted different connection patterns as well as varied lengths of the deflectors..During the experiment,focused on the working principle of the solar air heat collector and did the numerical simulation analysis jobs for the temperature fields inside the cavity with varied series-parallel connections or deflectors with different lengths using software like Fluent based on the theories of heat transferring and aerodynamics.With the results of the tests,we redesigned the connection pattern as well as inner structure of the solar air heat collector in order to improve the heat collecting efficiency and reduce the cost of the drying process.This paper has done the following jobs:First of all,with other variables controlled,the single-factor and multifactor interaction experiment testing the heat-collecting efficiency of different flat plate solar air heat collectors with different connection patterns and lengths of the deflectors.Also,with the help of the software like Fluent,we finished the simulation analysis on the inner temperature fields of flat plate solar air heat collectors with varied connection pattern and lengths of the deflectors.The synthetic effects of the series-parallel connection patterns and lengths of the deflectors are tested and the results were discussed based on the theories like heat transferring and aerodynamics.Thirdly,concerning the distribution of the inner temperature fields,modified design of the flat plate collectors with improved connection pattern as well as proper length of the deflector were offered in the paper,which can help to greatly improve the efficiency and reduce the cost of the drying process.Based on the results from the experiment,further improvement can get some inspirations. |
