One primordial consideration in residential ventilation standards is the comfort of provided to people living in those habitations.This is highly dependent on the thermal and fluid flow conditions,the space geometry a...One primordial consideration in residential ventilation standards is the comfort of provided to people living in those habitations.This is highly dependent on the thermal and fluid flow conditions,the space geometry and so on.Efficient designs may reduce the energy usage,making the buildings more sustainable over a longer period of time.This study aims to investigate the impact of whole day thermal conditions on the fluid flow structure and heat transfer phenomena,mainly natural convection,inside a partitioned attic-shaped configuration.The Finite Volume Method is applied to solve the governing equations.Sinusoidal thermal boundary condition is applied on the sloping walls to illustrate the characteristics of primary flow through daily cycles.A highly thermal conductive partition was placed vertically at the middle of the cavity.Note that through the partition,only heat could freely transfer between two fluid zones.Results show that,during day time,a stratified fluid flow structure is obtained,which originates from the prevailing conduction heat transfer mechanism,while,for the night-time it changed into a strong convection mechanism which significantly affects the flow structure.These results are particularly important for understanding the fluid dynamics inside the attic shaped building and also designing new residential building.展开更多
Two attics were constructed as part of a building renovation project at the University of West Florida.The first attic is described as a traditional ventilated attic,with open-ings in the soffits and a small dormer ve...Two attics were constructed as part of a building renovation project at the University of West Florida.The first attic is described as a traditional ventilated attic,with open-ings in the soffits and a small dormer vent on the roof.The second attic is described as a sealed attic(with no ventilation),and open-cell spray foam insulation installed on the underside of the roof deck.The study was undertaken to demonstrate hypoth-esized performance differences between attic types.Thermal and relative humidity sensors were installed to measure the condition of the air in the two attics spaces,and measurements were taken at 15 minute intervals.Measurements of relative humidity were later calculated as dew point and specific humidity.Similar studies are often conducted by comparison of attics in separate buildings under different use condi-tions.This project offers a unique opportunity to explore data collected from a single structure,and provides support for existing research on attic design in southern regions.The resultant data show significant differences in attic temperatures,with the sealed attic exhibiting a much more thermally stable pattern.There were also significant differences in attic dew points and specific humidity,although these dif-ferences appear to be much less pronounced.Data were analyzed using independent t-tests to establish significant differences between means.Overall,the sealed attic performed better than the ventilated attic,although dew point and specific humidity remain concerns.展开更多
The University of Florida(UF)and the Oak Ridge National Laboratory(ORNL)are evaluating the hygrothermal(heat and moisture flow)performance and durability of sealed attic construction where open cell spray polyurethane...The University of Florida(UF)and the Oak Ridge National Laboratory(ORNL)are evaluating the hygrothermal(heat and moisture flow)performance and durability of sealed attic construction where open cell spray polyurethane foam(ocSPF)insulation is applied directly to the underside of the roof deck.During the 2015-2016 fiscal year and with financial support from the Florida Building Commission(FBC)and the Florida Roofing and Sheet Metal Contractors Association(FRSA),UF and the ORNL Building Technology Research Integration Center(BTRIC)completed Phase I of a study that setup four residential home demonstrations in Florida climate zones CZ-1A and CZ-2A.Field measurements for the homes are listed in Table 1.The four homes are instrumented for measuring temperature and relative humidity of the indoor living space,the outdoor air and the attic air.In addition,the temperature,relative humidity and moisture content of the roof sheathing are being monitored and recorded by remotely-accessible data acquisition equipment.Air leakage tests on the whole house,on the sealed attic and in the HVAC ducts were conducted on all four homes,Table 1.Digital and infrared images were captured to document the thermal performance of the sealed attics.Field tests commenced on June 1,2016.Data acquisition will continue for one full year to document heat and moisture flows,which,in turn will be used in a second phase of work to benchmark an analytical tool kit for predicting the heat and moisture flows in Florida’s hot and humid climate.The second phase of work is pending approval by the FBC.展开更多
目的探讨全耳内镜下经外耳道处理上鼓室胆脂瘤的手术方法、术后效果以及临床应用特点。方法回顾性分析我科自2016年1月至2017年1月收治的中耳上鼓室胆脂瘤并行全耳内镜下手术的患者。选取符合标准的病例总数47例,男28例,女19例;年龄15~6...目的探讨全耳内镜下经外耳道处理上鼓室胆脂瘤的手术方法、术后效果以及临床应用特点。方法回顾性分析我科自2016年1月至2017年1月收治的中耳上鼓室胆脂瘤并行全耳内镜下手术的患者。选取符合标准的病例总数47例,男28例,女19例;年龄15~68岁,平均41岁。术中常规取耳屏软骨-软骨膜复合物修补鼓膜、重建上鼓室,于耳内镜下清除胆脂瘤,行鼓室成形术,根据具体情况行上鼓室重建术、听骨链重建术。分别于术后1月、2月、3月和6月复查。结果所有47例患者中,32例(68%)为局限在上鼓室的胆脂瘤,15例(32%)为胆脂瘤同时累及中鼓室、前鼓室;其中21例(45%)听骨链完整,26例(55%)锤骨/砧骨有破坏。其中29例行听骨链重建术。所有患者术后均无面瘫、耳流脓、鼓膜穿孔。术后复查,所有患者的鼓膜形态良好,无内陷、无穿孔,移植物形态良好。术前平均气导听阈为43.45±9.56 d B HL,术后平均气导听阈为27.23±6.89 d B HL,术前术后比较具有统计学差异(P<0.01)。术前平均气骨导差为28.42±6.78 d B HL,术后平均气骨导差为13.62±8.67d B HL,术前术后比较具有统计学差异(P<0.01)。其中29例行听骨链重建术者,术后气骨导差<10d B HL者11例,10~20d B HL者13例,20~30d B HL者3例,>30d B HL者2例。所有患者均未出现病变复发、病变残余,无二次手术者。结论全耳内镜经外耳道手术处理上鼓室胆脂瘤是一种安全有效的手术方法。展开更多
目的探讨重建上鼓室外侧壁在开放式乳突根治中的意义。方法选择开放式乳突根治的病人,同时应用同种异体鼻中隔软骨或自体乳突皮质骨,重建上鼓室外侧壁,完成上鼓室成形术20例。结果20例手术均获得干耳,术后3～6个月平均气导听力提高20 d...目的探讨重建上鼓室外侧壁在开放式乳突根治中的意义。方法选择开放式乳突根治的病人,同时应用同种异体鼻中隔软骨或自体乳突皮质骨,重建上鼓室外侧壁,完成上鼓室成形术20例。结果20例手术均获得干耳,术后3～6个月平均气导听力提高20 dB以上4耳,10～20 dB 13耳。结论应用同种异体鼻中隔软骨或自体乳突皮质骨,重建上鼓室外侧壁,能改善行开放式乳突根治病人的听力。展开更多
目的探讨耳内镜下耳屏软骨-软骨膜重建外耳道后壁或上鼓室外侧壁的临床应用及术后效果。方法回顾性分析2015年8月~2019年8月期间住院手术的52例(52耳)外耳道及中耳胆脂瘤患者的临床资料,病变均累及上鼓室及鼓窦,其中45例为中耳胆脂瘤,7...目的探讨耳内镜下耳屏软骨-软骨膜重建外耳道后壁或上鼓室外侧壁的临床应用及术后效果。方法回顾性分析2015年8月~2019年8月期间住院手术的52例(52耳)外耳道及中耳胆脂瘤患者的临床资料,病变均累及上鼓室及鼓窦,其中45例为中耳胆脂瘤,7例为外耳道胆脂瘤,均在耳内镜下行上鼓室开放术同期行鼓室成形,术中用耳屏软骨-软骨膜重建上鼓室外侧壁或外耳道后壁,分析手术技术要点、观察术后干耳时间、鼓膜愈合、上鼓室外侧壁塌陷及听力疗效等相关情况。结果52例(52耳)术后平均随访时间26.3±7.2个月,术后平均干耳时间27.5±8.8天;鼓膜完全愈合47耳(90.4%,47/52),其中鼓膜完全愈合且形态正常41耳(78.8%,41/52),鼓膜愈合但内陷6耳(11.5%,6/52);复发5耳(9.6%,5/52),其中紧张部内陷穿孔1耳(1/52,1.9%),松弛部内陷伴穿孔4耳(4/52,7.7%);无一例面瘫和外耳道狭窄。术后12个月,0.5、1、2、4 kHz平均气导听阈(32.1±5.8 dB HL)较术前(53.2±10.4 dB HL)明显降低(P<0.001),ABG(15.6±7.6 dB)值较术前(41.5±7.4 dB)明显降低(P<0.001)。结论对于累及上鼓室的外耳道或中耳胆脂瘤,可经耳内镜行上鼓室开放术清除病变,用耳屏软骨-软骨膜重建上鼓室外侧壁或外耳道后壁,依靠软骨的支撑,可维持鼓室、鼓窦及乳突腔含气腔,减少鼓膜松弛部内陷的发生,保持上鼓室外侧壁的基本形态。展开更多
文摘One primordial consideration in residential ventilation standards is the comfort of provided to people living in those habitations.This is highly dependent on the thermal and fluid flow conditions,the space geometry and so on.Efficient designs may reduce the energy usage,making the buildings more sustainable over a longer period of time.This study aims to investigate the impact of whole day thermal conditions on the fluid flow structure and heat transfer phenomena,mainly natural convection,inside a partitioned attic-shaped configuration.The Finite Volume Method is applied to solve the governing equations.Sinusoidal thermal boundary condition is applied on the sloping walls to illustrate the characteristics of primary flow through daily cycles.A highly thermal conductive partition was placed vertically at the middle of the cavity.Note that through the partition,only heat could freely transfer between two fluid zones.Results show that,during day time,a stratified fluid flow structure is obtained,which originates from the prevailing conduction heat transfer mechanism,while,for the night-time it changed into a strong convection mechanism which significantly affects the flow structure.These results are particularly important for understanding the fluid dynamics inside the attic shaped building and also designing new residential building.
文摘Two attics were constructed as part of a building renovation project at the University of West Florida.The first attic is described as a traditional ventilated attic,with open-ings in the soffits and a small dormer vent on the roof.The second attic is described as a sealed attic(with no ventilation),and open-cell spray foam insulation installed on the underside of the roof deck.The study was undertaken to demonstrate hypoth-esized performance differences between attic types.Thermal and relative humidity sensors were installed to measure the condition of the air in the two attics spaces,and measurements were taken at 15 minute intervals.Measurements of relative humidity were later calculated as dew point and specific humidity.Similar studies are often conducted by comparison of attics in separate buildings under different use condi-tions.This project offers a unique opportunity to explore data collected from a single structure,and provides support for existing research on attic design in southern regions.The resultant data show significant differences in attic temperatures,with the sealed attic exhibiting a much more thermally stable pattern.There were also significant differences in attic dew points and specific humidity,although these dif-ferences appear to be much less pronounced.Data were analyzed using independent t-tests to establish significant differences between means.Overall,the sealed attic performed better than the ventilated attic,although dew point and specific humidity remain concerns.
文摘The University of Florida(UF)and the Oak Ridge National Laboratory(ORNL)are evaluating the hygrothermal(heat and moisture flow)performance and durability of sealed attic construction where open cell spray polyurethane foam(ocSPF)insulation is applied directly to the underside of the roof deck.During the 2015-2016 fiscal year and with financial support from the Florida Building Commission(FBC)and the Florida Roofing and Sheet Metal Contractors Association(FRSA),UF and the ORNL Building Technology Research Integration Center(BTRIC)completed Phase I of a study that setup four residential home demonstrations in Florida climate zones CZ-1A and CZ-2A.Field measurements for the homes are listed in Table 1.The four homes are instrumented for measuring temperature and relative humidity of the indoor living space,the outdoor air and the attic air.In addition,the temperature,relative humidity and moisture content of the roof sheathing are being monitored and recorded by remotely-accessible data acquisition equipment.Air leakage tests on the whole house,on the sealed attic and in the HVAC ducts were conducted on all four homes,Table 1.Digital and infrared images were captured to document the thermal performance of the sealed attics.Field tests commenced on June 1,2016.Data acquisition will continue for one full year to document heat and moisture flows,which,in turn will be used in a second phase of work to benchmark an analytical tool kit for predicting the heat and moisture flows in Florida’s hot and humid climate.The second phase of work is pending approval by the FBC.
文摘目的探讨全耳内镜下经外耳道处理上鼓室胆脂瘤的手术方法、术后效果以及临床应用特点。方法回顾性分析我科自2016年1月至2017年1月收治的中耳上鼓室胆脂瘤并行全耳内镜下手术的患者。选取符合标准的病例总数47例,男28例,女19例;年龄15~68岁,平均41岁。术中常规取耳屏软骨-软骨膜复合物修补鼓膜、重建上鼓室,于耳内镜下清除胆脂瘤,行鼓室成形术,根据具体情况行上鼓室重建术、听骨链重建术。分别于术后1月、2月、3月和6月复查。结果所有47例患者中,32例(68%)为局限在上鼓室的胆脂瘤,15例(32%)为胆脂瘤同时累及中鼓室、前鼓室;其中21例(45%)听骨链完整,26例(55%)锤骨/砧骨有破坏。其中29例行听骨链重建术。所有患者术后均无面瘫、耳流脓、鼓膜穿孔。术后复查,所有患者的鼓膜形态良好,无内陷、无穿孔,移植物形态良好。术前平均气导听阈为43.45±9.56 d B HL,术后平均气导听阈为27.23±6.89 d B HL,术前术后比较具有统计学差异(P<0.01)。术前平均气骨导差为28.42±6.78 d B HL,术后平均气骨导差为13.62±8.67d B HL,术前术后比较具有统计学差异(P<0.01)。其中29例行听骨链重建术者,术后气骨导差<10d B HL者11例,10~20d B HL者13例,20~30d B HL者3例,>30d B HL者2例。所有患者均未出现病变复发、病变残余,无二次手术者。结论全耳内镜经外耳道手术处理上鼓室胆脂瘤是一种安全有效的手术方法。
文摘目的探讨重建上鼓室外侧壁在开放式乳突根治中的意义。方法选择开放式乳突根治的病人,同时应用同种异体鼻中隔软骨或自体乳突皮质骨,重建上鼓室外侧壁,完成上鼓室成形术20例。结果20例手术均获得干耳,术后3～6个月平均气导听力提高20 dB以上4耳,10～20 dB 13耳。结论应用同种异体鼻中隔软骨或自体乳突皮质骨,重建上鼓室外侧壁,能改善行开放式乳突根治病人的听力。
文摘目的探讨耳内镜下耳屏软骨-软骨膜重建外耳道后壁或上鼓室外侧壁的临床应用及术后效果。方法回顾性分析2015年8月~2019年8月期间住院手术的52例(52耳)外耳道及中耳胆脂瘤患者的临床资料,病变均累及上鼓室及鼓窦,其中45例为中耳胆脂瘤,7例为外耳道胆脂瘤,均在耳内镜下行上鼓室开放术同期行鼓室成形,术中用耳屏软骨-软骨膜重建上鼓室外侧壁或外耳道后壁,分析手术技术要点、观察术后干耳时间、鼓膜愈合、上鼓室外侧壁塌陷及听力疗效等相关情况。结果52例(52耳)术后平均随访时间26.3±7.2个月,术后平均干耳时间27.5±8.8天;鼓膜完全愈合47耳(90.4%,47/52),其中鼓膜完全愈合且形态正常41耳(78.8%,41/52),鼓膜愈合但内陷6耳(11.5%,6/52);复发5耳(9.6%,5/52),其中紧张部内陷穿孔1耳(1/52,1.9%),松弛部内陷伴穿孔4耳(4/52,7.7%);无一例面瘫和外耳道狭窄。术后12个月,0.5、1、2、4 kHz平均气导听阈(32.1±5.8 dB HL)较术前(53.2±10.4 dB HL)明显降低(P<0.001),ABG(15.6±7.6 dB)值较术前(41.5±7.4 dB)明显降低(P<0.001)。结论对于累及上鼓室的外耳道或中耳胆脂瘤,可经耳内镜行上鼓室开放术清除病变,用耳屏软骨-软骨膜重建上鼓室外侧壁或外耳道后壁,依靠软骨的支撑,可维持鼓室、鼓窦及乳突腔含气腔,减少鼓膜松弛部内陷的发生,保持上鼓室外侧壁的基本形态。
