Down Material Changes Affect The Compatibility Of The Warm

Warm materials are developed on the basis of the development of the textile industry. Now they are booming and each of them has its own unique advantages and competitiveness. To be warmer and more comfortable is a constant researching field. In order to make the most use of the thermal properties of down jacket materials and keep them at the best situation constantly, reasonably distributing the warm material to each part of the body is particularly important. The difference of skin’s cold sensation laws among body parts is the basis of design for thermal insulation and warmth retention clothes. In this paper, a method of increasing local temperature to keep warmth was adopted and the best thermodynamic ratio of down jacket materials was studied by analyzing surface temperature values and cold and warm sensory evaluation values of different parts of body.Aiming at body characteristics of northern consumer market, down jacket style favored by northerner according to their shoulder width and body thickness was designed and the warmth retention of a fixed style—short or long down jacket was studied respectively. It’s mainly divided into 3 parts in the followings:(1) Establish a dress testing method of warmth retention of down jacket. In order to evaluate the warmth retention, current domestic and international studies have generally used a flat-panel insulation tester or thermal manikin. But there is a big difference between the plane sample and cloth shape:ifferent feather styles have different surface area, and the thermal resistance is different too, and garment construction difference also lead to different thermal resistance. Therefore, the test results of warmth different from clothes styles, and Manikin size, test conditions, different methods to calculate the thermal resistance in the test results in certain limitations of guiding down jacket design.In view of the problems caused by defects in the above experimental test, we design a method of non-steady state to test down jacket warmth-dressing experiments. Choosing seven test points according to the down jacket style and experiment in a condition of constant temperature and humidity. The seven temperature sensors were adhered sequentially to the seven test points of the inner jacket by breathable medical transparent tape of Nexcare. At the same time, the real-time temperature changes were recorded. During the test, the subjects were keep sitting and making oral report value of cold、warmth and comfort and the entire testing process last 5 minutes.(2) The influence of filler materials to warmth retention of short down jacket. Choose four short down jacket with different filler materials and compare their warmth retention. Result shows that JCDecaux nano—velvet has best warmth retention,followed by Poland goose down. At the same time, fill JCDecaux nano—velvet in abdomen and chest and fill Poland goose down in waist spot to make it lighter and warmer.Four short down jacket fabrics are flannel, and the inside are pongee lining. Filling materials are 90% ordinary white duck down, JCDecaux nano—velvet, lion white goose down, Poland goose down,and the filling amount is 137.1g. Record the real-time temperature of each test point. Given the test was carried out in a non-steady state, the data were processed segmently. The dress experiment(objective data) of time- temperature curve was divided into steady and unsteady part. In the unsteady part, according to Manliedisi method to obtain the maximum point of temperature change rate. Then, temperature curve of this period will be fitting a straight line. The temperature change rate dTdtof four different filler jacket represents its energy story speed. In addition, the area of each part of the time- temperature curve is to compare the differences of different filler jacket’s local accumulation amount.In addition, the steady-state use average temperature(℃) and initial temperature difference △ Tsk(℃). In the constant condition, change clothes CLO value in the case when the subject does not sweat, then the average human skin temperature will change. The higher the average human skin temperature, the greater the CLO, and the better the warmth retention property. The initial temperature difference △ Tsk(℃) determines the amount of heat exchange. The bigger the difference between the initial temperature, the larger the energy story. A combination of subjective evaluation of test subjects(the value of cold and warmth, comfort value) and finally come to a conclusion that JCDecaux nano—velvet has best warmth retention, followed by Poland goose down. Then according to the body’s cold-sensitive sort, partial fill in the abdomen and chest parts with JCDecaux nano—velvet, and fill in the waist spot with Poland imported goose down filling to make the down jacket lighter and warmer.(3) The influence of filling amount to warmth retention of long down jacket. Using control variable method, and compare the warmth retention of these four long down jacket with only different filling amount. Results show that when the filling material is 90% ordinary white duck down, the optimum filling amount of 120 g / m2.Choose four different filling amount of long down jacket.The fabrics are flannel, and the inside are pongee lining and the filler material is 90% ordinary white duck down.The filling amount was 120 g / m2,150 g / m2,180 g / m2,210 g / m2 respectively. Record the changes of surface temperature and the value of cold 、warmth and comfort to get the optimum filling amount. Firstly, observe the time- temperature profiles of experimental test. The result is that time-temperature curve trend in seven parts of the four kinds of filling amount down jacket is same within 0-5min.There is no obvious rise and drop, which indicates that the seven parts has little fluctuations when the subject wearing the same clothes and it is not affected by other conditions. It can be conclude that the experimental test data are stable and reliable, which reduce the error when analyze them.Secondly, analyze the total accumulated energy of the four down jacket during the entire testing process. That is represented by the various parts’ areas under the curve. The bigger the area under the curve, the more energy it accumulates; Then, compare the average temperature(℃) and the initial temperature difference △ Tsk(℃). Finally, combine with the scoring value of cold、warms and comfort of the subject, the relationship of filling amount, temperature changes and warm and cold sense. The results show that when fill 90% ordinary white duck down and the filling amount is120 g / m2, the warmth retention is best, and when filling amount is 150 g / m2, the warmth retention is worst. Then the warmth increasing slowly with the rising of filling amount, and the bigger the filling amount, the less comfortable to our subject. Based on the above discuss and cost-reduced principle, the optimum filling amount of 120 g / m2.To sum up: as the total filling amount is a short down jacket weighing 137.1g, when the fillers are 90% ordinary white duck down, JCDecaux nano—velvet, lion white goose down and Poland goose down respectively, JCDecaux nano—velvet shows the best warmth. Partial filling according to cold and warm feelings of human body, it is recommended to fill JCDecaux nano—velvet in the abdomen and chest parts, and fill Poland goose down in the waist. Filling material is 90% ordinary white duck down in long down jacket, when the filling amount are 120 g / m2,150 g / m2,180 g / m2 and 210 g / m2, the best is 120 g / m2. The conclusions can provide guidance for the company to develop warmer down jacket, and finally design down jacket with excellent thermal properties and forward-looking creativity.