Study On Large Temperature Difference Air Distribution And VAV Air Conditioning Systems In Ships

In recent years, under the trends of pursuing a safer and more energy-efficientenvironment the International Maritime Organization has introduced new norms and newstandards,so China’s shipbuilding industry should adapt to the new international standards inshipbuilding, and establish advanced shipbuilding modes to make our country from a bigshipbuilding to be a shipbuilding power. So from the technical level we should not onlyfurther optimize the hull form, reduce lightship weight, use a large number of energy savingpower systems, but also further improve the living and working environment, the paper has acomprehensive research on ship air conditioning saving energy and the thermal comfortablyof the crews room.As the target of saving energy and thermal comfort, large temperature difference at lowtemperature air supply technology with variable air volume and the combination oftemperature and humidity independent control system solutions is put forward by optimizinglarge temperature difference air-conditioning system design parameters, the selection ofterminal devices, different analysis comparison of the air flow field and the applicationtemperature humidity independent control technology for clues. In terms of system feasibilitystudy, compared with the conventional air conditioning system the system has manyadvantages.At first, it reduces the energy consumption and enhances the capacity of theadjustment and controls of air conditioning cooling dehumidification.Secondly it reduces airconditioning supply air and water and reduces the air conditioning fan noise and reduced thesize and weight of equipment and piping. As a result, the system not only can be used in shipair conditioning systems and the system technology to meet the new standards andspecification requirements.In cabin thermal comfort research, using the CFD software simulation cabin temperaturefield and velocity field under different air supply temperature difference of the flow fielddistribution of the cabin were studied under different air supply temperature difference whendifferent air volume flow field distribution. Results show that when the delivery is100%airsupply, the cabin comfort of15℃air dew point is best, and big difference in temperature5℃,7℃low temperature air supply cabin comfort due to low supply air temperature, wind speedis too big, make the cabin has drooping cold air and strong feeling. When air output of70%air supply,7℃air dew point cabin comfort is the best. When air output of50%air supply, the cabin comfort of5℃air dew point is best, because the supply air velocity is small, does notcause air staff feeling. Therefore, the appropriate conditions of large temperature differenceair supply technology in ship air conditioning systems can achieve satisfactory results.