learnmech.com/importance-of-turbulence-swirl-squish-tumble-related-to-ci-engine Turbulence is very important for close to complete combustion. Swirl, Squish, and Tumble are used to create turbulence in internal combustion engines. Kirk Harris discovered that a static fan shape with overlapping 70 degree blades creates lots of fast moving swirl at the approximately one to two meter per second velocities found in TLUDs. […]
In the last Newsletter, we announced the publication of Aprovecho’s recent research on the Jet-Flame, “Retrofitting stoves with forced jets of primary air improves speed, emissions, and efficiency: Evidence from six types of biomass cookstoves” Here is a simplified summary of the findings: When the goals for biomass cook stove interventions were raised to include protecting […]
The Journal “Energy for Sustainable Development” has just published Aprovecho’s most recent research paper, “Retrofitting stoves with forced jets of primary air improves speed, emissions, and efficiency: Evidence from six types of biomass cook stoves.” It was authored by Samuel Bentson, David Evitt, Dean Still, Dr. Daniel Lieberman and Dr. Nordica MacCarty (Energy for Sustainable Development 71 […]
The Rocket stove requires forced draft to create sufficient mixing in the flame to achieve Tier 4 for PM2.5. In addition, when sticks are pushed too fast into the Rocket, too much wood gas enters the combustion zone and a lot of smoke is emitted. Metering of the fuel is necessary to keep the Rocket […]
Before starting to develop cleaner burning cook stoves in the 2013-2015 DOE project, ARC researchers completed a survey of best performing existing stoves. Improving combustion efficiency to protect health (and climate) has continued as various cook stove organizations have worked tirelessly to meet the WHO 2015 PM2.5 Intermediate Emission Rate Target of 1.75mg/minute, calculated to […]
How can smoke, extremely dangerous for health and climate change, be ignored in carbon credit equations? Carbon dioxide and methane are counted but not smoke. Carbon dioxide is reduced when heat transfer is improved resulting in less wood being burned. Wood doesn’t make appreciable amounts of methane. Because smoke is not counted to earn carbon […]
The investigation of how to reduce emissions and fuel use in biomass stoves continued with support from an EPA SBIR award. Two products were manufactured by our Chinese partner SSM, a heating/cooking stove and the Jet-Flame, a $12 insert that has made stoves 67% cleaner burning in field tests. https://www.jet-flame.com/ The Gates funded Global Health Labs […]
In 2011, Dr. Samuel Baldwin at the Department of Energy (who wrote the Bible on cook stoves in 1987) organized a two-day 100 person conference to identify how cook stoves could be improved and manufactured. Key recommendations were: At least 90% emissions reduction and 50% fuel savings are appropriate initial targets for biomass cook stoves. Multiple […]
In 2009, The New Yorker published an article about the Rocket stove entitled Hearth Surgery: The quest for a stove that can save the world. One year later, USAID funded field tests in Africa showed that the insulated Rocket stove was not cleaner burning than the open fire. The Rocket with skirt saved 40% of the […]
Kirk Harris has been investigating TLUDs for decades and, as far as I know, his natural draft TLUD burning pellets achieved the lowest natural draft recorded score for PM2.5: 0.7mg/minute at high power (Lawrence Berkeley National Laboratory). This video shows Kirk in China at Shengzhou Stove Manufacturer where Mr. Shen built a copy of his […]